Selektywna niedobór iga
Epidemiologia

Selektywny niedobór immunoglobuliny A (SIgAD), definiowany jako poziom IgA w surowicy poniżej 0,07 g/L przy prawidłowych poziomach IgG i IgM, jest najczęstszym pierwotnym niedoborem odporności, o częstości występowania w populacji ogólnej od 1:100 do 1:1000, z wyraźnymi różnicami etnicznymi. Najwyższa częstość obserwowana jest u osób rasy białej, zwłaszcza europejskiego pochodzenia (np. 1:143 na Półwyspie Arabskim, 1:163 w Hiszpanii), natomiast najniższa w populacjach azjatyckich (np. 1:2600–1:5300 w Chinach, 1:14840–1:18500 w Japonii). SIgAD wykazuje silne predyspozycje rodzinne, z 7,5% częstością u krewnych pierwszego stopnia i około 20% ryzykiem dziedziczenia, co wskazuje na istotny komponent genetyczny, w tym związek z haplotypami HLA-B8, DR3, DQ2. Choroba współwystępuje często z autoimmunizacją, zwłaszcza celiakią (częstość SIgAD 1:39–1:57), cukrzycą typu 1 (1:27–1:261), toczniem rumieniowatym układowym, chorobami tarczycy i innymi schorzeniami autoimmunologicznymi, co podkreśla wspólne podłoże immunogenetyczne.

  1. Epidemiologia selektywnego niedoboru IgA – występowanie na świecie
    1. Czynniki wpływające na częstość występowania
  2. Predyspozycje rodzinne i czynniki genetyczne
    1. Związki z układem HLA
  3. Częstość występowania w określonych schorzeniach
    1. Choroby autoimmunologiczne
    2. Choroby alergiczne
  4. Selektywny niedobór IgA a choroby układu oddechowego
  5. Selektywny niedobór IgA a COVID-19
  6. Nadzór epidemiologiczny i badania przesiewowe
    1. Nadzór nad reakcjami poprzetoczeniowymi
  7. Jakość życia i długoterminowy nadzór
  8. Podsumowanie danych epidemiologicznych
    1. Kolejne rozdziały

Epidemiologia selektywnego niedoboru IgA – występowanie na świecie

Selektywny niedobór immunoglobuliny A (SIgAD) jest najczęściej występującym pierwotnym niedoborem odporności na świecie. Częstość występowania tego schorzenia zależy w dużej mierze od pochodzenia etnicznego populacji i wykazuje znaczące różnice geograficzne. Szacowana częstość występowania w populacji ogólnej waha się od 1:100 do 1:1000, przy czym dokładniejsze dane wskazują na zakres od 1:143 do 1:965 w różnych regionach świata.12

Selektywny niedobór IgA występuje najczęściej u osób rasy białej, szczególnie pochodzenia europejskiego. Najwyższą częstość odnotowano na Półwyspie Arabskim (1:143), w Hiszpanii (1:163), Nigerii (1:252), natomiast niższą w Anglii (1:875) i Brazylii (1:965).3 W Stanach Zjednoczonych częstość występowania szacuje się na zakres od 1:223 do 1:1000 w badaniach populacyjnych oraz od 1:333 do 1:3000 wśród zdrowych dawców krwi.4

Co istotne, częstość występowania SIgAD jest znacząco niższa w populacjach azjatyckich. W Chinach wynosi od 1:2600 do 1:5300, a w Japonii od 1:14840 do 1:18500, co wskazuje na wyraźne różnice etniczne w dystrybucji tego niedoboru.56 Wśród Afroamerykanów częstość występowania szacuje się na 1:6000.7

Czynniki wpływające na częstość występowania

Rzeczywista częstość występowania selektywnego niedoboru IgA może być wyższa niż wskazują oficjalne dane z kilku powodów. Przede wszystkim brakuje rutynowych programów przesiewowych wykrywających niedobory immunologiczne. Ponadto, u wielu pacjentów choroba przebiega bezobjawowo, co utrudnia jej rozpoznanie.89

Warto zauważyć, że dane dotyczące częstości występowania mogą różnić się również z powodu różnych definicji selektywnego niedoboru IgA przyjmowanych w poszczególnych badaniach i rejestrach. Niejednolite projektowanie badań w różnych krajach, które często obejmują osoby z określonymi schorzeniami, może nie odzwierciedlać rzeczywistej częstości występowania SIgAD w całej populacji.1011

Predyspozycje rodzinne i czynniki genetyczne

Selektywny niedobór IgA wykazuje silne predyspozycje rodzinne. Badania epidemiologiczne wskazują, że częstość występowania tego niedoboru wśród krewnych pierwszego stopnia pacjentów z SIgAD jest około 38-krotnie wyższa niż u niespokrewnionych dawców.1213 W badaniach rodzinnych wykorzystujących dawców krwi z SIgAD jako probandów wykazano, że u krewnych pierwszego stopnia częstość występowania SIgAD wynosi 7,5%, co potwierdza znaczącą rolę czynników genetycznych.14

Szansa na odziedziczenie schorzenia w rodzinie wynosi około 20%, co sugeruje znaczący komponent genetyczny w etiologii choroby.1516 Selektywny niedobór IgA jest również obserwowany w rodzinach z pospolitym zmiennym niedoborem odporności (CVID), co wskazuje na potencjalne wspólne podłoże genetyczne tych zaburzeń.17

Wysoką częstość występowania SIgAD obserwuje się także u krewnych pierwszego stopnia pacjentów z objawowym SIgAD w małżeństwach między krewnymi, co dodatkowo potwierdza rodzinne uwarunkowanie schorzenia.18 Z tego powodu zaleca się badania przesiewowe u krewnych pierwszego stopnia pacjentów z SIgAD.

Związki z układem HLA

Selektywny niedobór IgA jest silnie związany z regionem głównego kompleksu zgodności tkankowej (MHC), w szczególności z haplotypem ludzkich antygenów leukocytarnych HLA-B8, DR3, DQ2. Do 45% pacjentów z SIgAD posiada co najmniej jedną kopię tego haplotypu, w porównaniu do 16% w populacji ogólnej.19

Inne haplotypy, w tym HLA-DR7, DQ2 i DR1, DQ5, również wykazują związek z SIgAD. Co ciekawe, ancestralny haplotyp 8.1 jest także związany z chorobą Gravesa-Basedowa, toczniem rumieniowatym układowym (SLE), cukrzycą typu 1 i chorobą trzewną, co może tłumaczyć częste współwystępowanie tych schorzeń u pacjentów z SIgAD.20

Częstość występowania w określonych schorzeniach

Częstość występowania selektywnego niedoboru IgA jest znacząco wyższa w niektórych chorobach autoimmunologicznych i alergicznych w porównaniu do populacji ogólnej. Ta zależność ma istotne znaczenie dla praktyki klinicznej i nadzoru epidemiologicznego.

Choroby autoimmunologiczne

W chorobie trzewnej (celiakii) częstość występowania SIgAD wynosi od 1:39 do 1:57, co stanowi 5-15-krotny wzrost w porównaniu do populacji ogólnej.2122 W dużym badaniu szwedzkim obejmującym 442 225 osób skierowanych do ośrodków immunologicznych z podejrzeniem celiakii, zidentyfikowano łącznie 971 dzieci i 1338 dorosłych z SIgAD, co daje częstość 1:192.23

W przypadku cukrzycy typu 1 częstość występowania SIgAD waha się od 1:27 do 1:261 w różnych badaniach, co wskazuje na 10-20-krotny wzrost ryzyka u pacjentów z SIgAD.2425 W badaniu przeprowadzonym w Ukrainie wykazano, że częstość występowania SIgAD wśród dzieci z cukrzycą typu 1 wynosi 2,9% (1:34), z przewagą u płci męskiej (85,7%).26

Zwiększoną częstość występowania SIgAD obserwuje się również w przypadku tocznia rumieniowatego układowego (od 1:19 w USA do 1:130 w Hiszpanii), chorób tarczycy, młodzieńczego idiopatycznego zapalenia stawów (JIA), reumatoidalnego zapalenia stawów, zapalnych chorób jelit oraz bielactwa.2728

Choroby alergiczne

Częstość występowania chorób alergicznych u pacjentów z SIgAD jest przedmiotem dyskusji, ponieważ badania z różnych krajów przedstawiają niespójne wyniki. Większość publikacji potwierdza związek między SIgAD lub niskim poziomem IgA a chorobami alergicznymi, ale niektórzy badacze kwestionują tę zależność.29

W badaniu przeprowadzonym w Ankarze w 2017 roku wykazano, że 45,7% pacjentów z rozpoznanym SIgAD prezentowało jedną z następujących chorób: astmę, zapalenie błony śluzowej nosa, wyprysk lub atopowe zapalenie skóry. Co interesujące, częstość występowania alergii w bliskiej rodzinie tych pacjentów wynosiła aż 43,2%.30

Badania analizujące alergie u pacjentów z SIgAD wykazały częstość występowania sięgającą nawet 84%, co potwierdza związek między SIgAD a chorobami alergicznymi. Najczęściej opisywane manifestacje alergiczne to astma, alergiczny nieżyt nosa, alergiczne zapalenie spojówek, pokrzywka, atopowe zapalenie skóry i alergia pokarmowa.31

Selektywny niedobór IgA a choroby układu oddechowego

Selektywny niedobór IgA występuje częściej u dorosłych pacjentów z przewlekłą chorobą płuc niż u zdrowych, dobranych pod względem wieku osób z grupy kontrolnej.32 20-letnie badanie podłużne zdrowych dawców krwi z przypadkowo wykrytym SIgAD, przeprowadzone przy użyciu kwestionariuszy i przeglądu dokumentacji medycznej, wykazało:

  • 3-krotny wzrost częstości ciężkich chorób układu oddechowego w dzieciństwie (9% vs 3%)33
  • 4-krotny wzrost częstości ciężkich chorób układu oddechowego u dorosłych (16% vs 4%)34
  • podobny wzrost częstości nawracających łagodnych infekcji dróg oddechowych35
  • znaczący wzrost częstości nawracających infekcji wirusowych (16% vs 1%)36

Gdy SIgAD jest związany z jednym lub więcej niedoborów podklas IgG lub upośledzeniem odpowiedzi na polisacharydy, u niektórych osób z SIgAD mogą rozwinąć się nawracające infekcje zatokowo-płucne, szczególnie u pacjentów z równoczesnym niedoborem podklas IgG 2 i/lub 4.37

Selektywny niedobór IgA a COVID-19

Znaczenie immunoglobuliny A zostało ponownie podkreślone w kontekście pandemii COVID-19. Badania wykazały, że ryzyko ciężkiego przebiegu COVID-19 u pacjentów z SIgAD było około 7,7-krotnie wyższe niż u innych pacjentów (iloraz szans [OR] 7,789; 95% przedział ufności [CI] 1,665-36,690, p=0,008) w analizie jednowymiarowej. W analizie wielowymiarowej ryzyko to było 4-krotnie wyższe (OR 4,053; 95% CI 1,182-13,903, p=0,026).38

Badacze wskazują również na ryzyko słabej odpowiedzi na SARS-CoV-2 po immunizacji w tej grupie pacjentów.39 U pacjentów z SIgAD liczba wirusów SARS-CoV-2 przenikających przez błony śluzowe może być zwiększona, prowadząc do powikłań, takich jak zespół burzy cytokinowej i zespół ostrej niewydolności oddechowej.40

Nadzór epidemiologiczny i badania przesiewowe

Obecnie brakuje rutynowych programów przesiewowych w kierunku selektywnego niedoboru IgA, co przyczynia się do niedoszacowania rzeczywistej częstości występowania tego schorzenia. Wyzwanie stanowi fakt, że około 50-90% osób dotkniętych SIgAD nie wykazuje objawów klinicznych.4142

W ostatnich latach dostępny stał się szybki test przeciwciał, który umożliwia badania przesiewowe populacyjne w celu rozpoznania selektywnego niedoboru IgA już u małych dzieci.43 W badaniu przeprowadzonym na Litwie z wykorzystaniem szybkiego testu przyłóżkowego do wykrywania niedoboru IgA w populacji o wcześniej nieznanej częstości występowania, zidentyfikowano cztery przypadki SIgAD wśród 1000 dzieci w wieku szkolnym, co daje częstość występowania 1:250 (0,4%, 95% CI 0,16-1,02%).44

Nadzór nad reakcjami poprzetoczeniowymi

Z perspektywy medycyny transfuzjologicznej, obecność przeciwciał anty-IgA u osób z niedoborem IgA może być przyczyną anafilaktycznych reakcji poprzetoczeniowych. Około 1-5% anafilaktycznych reakcji poprzetoczeniowych w populacji kaukaskiej może być związanych z przeciwciałami anty-IgA u biorców z niedoborem IgA.45

W programie badań przesiewowych Canadian Blood Services, przeciwciała anty-IgA zidentyfikowano u 41% dawców z ciężkim niedoborem IgA. Jednak rzeczywista częstość anafilaktycznych reakcji związanych z przeciwciałami anty-IgA jest niższa niż 1 na 500 000 przetoczonych składników rocznie, co sugeruje, że nawet przy obecności przeciwciał anty-IgA u biorcy, ryzyko ciężkiej reakcji alergicznej lub anafilaktycznej jest niskie.46

Jakość życia i długoterminowy nadzór

Badania jakości życia (QOL) pacjentów z selektywnym niedoborem IgA wykazały, że niskie wyniki QOL były związane z bezrobociem, infekcjami w więcej niż 4 narządach i występowaniem więcej niż 2 dodatkowych chorób. Osoby z SIgAD miały znacząco wyższe wyniki indeksu QOL niż osoby z innymi niedoborami przeciwciał.47

Długoterminowy nadzór nad pacjentami z SIgAD stanowi wyzwanie ze względu na niezwykle zmienne fenotypy, od całkowicie bezobjawowych po ciężkie infekcje, alergie i choroby autoimmunologiczne. W badaniu z co najmniej pięcioletnim okresem obserwacji po rozpoznaniu SIgAD wykazano ze statystyczną istotnością, że wiek wystąpienia infekcji, alergii i chorób autoimmunologicznych był zmienny.48

Regularne monitorowanie poziomów IgA jest konieczne, z uwzględnieniem możliwości normalizacji; jednak ciągła obserwacja jest niezbędna ze względu na ryzyko progresji do innych niedoborów odporności, rozwoju chorób autoimmunologicznych i konieczności nadzoru onkologicznego.49

Podsumowanie danych epidemiologicznych

Selektywny niedobór IgA, definiowany jako poziom IgA w surowicy poniżej 0,07 g/L przy prawidłowych poziomach IgG i IgM, jest najczęstszym pierwotnym niedoborem odporności na świecie. Częstość występowania waha się od 1:100 do 1:1000, z wyraźnymi różnicami etnicznymi – najwyższa jest wśród osób rasy białej, szczególnie pochodzenia europejskiego, a najniższa w populacjach azjatyckich.50

Istotnym aspektem epidemiologii SIgAD jest jego silny związek z chorobami autoimmunologicznymi, w tym chorobą trzewną, cukrzycą typu 1, toczniem rumieniowatym układowym i chorobami tarczycy, co sugeruje wspólne podłoże genetyczne tych schorzeń, obejmujące zarówno geny MHC, jak i geny niezwiązane z MHC.51

Dane epidemiologiczne podkreślają również związek między SIgAD a zwiększoną podatnością na infekcje układu oddechowego i pokarmowego oraz choroby alergiczne, co ma istotne implikacje dla praktyki klinicznej i nadzoru nad tą grupą pacjentów.52

Brak rutynowych programów przesiewowych i wysoki odsetek przypadków bezobjawowych przyczynia się do niedoszacowania rzeczywistej częstości występowania SIgAD. Rozwój szybkich testów diagnostycznych może ułatwić wczesne wykrywanie i lepszy nadzór epidemiologiczny nad tym schorzeniem w przyszłości.53

Kolejne rozdziały

Zapraszamy do dalszego czytania naszego leksykonu.

Wybierz kolejny rozdział z menu poniżej, aby otworzyć nową podstronę kompedium wiedzy i uzyskać szczegółowe informację o leku, substancji lub chorobie.

  1. 09.04.2026
  2. www.leksykon.com.pl

Materiały źródłowe

  • #1 Selective IgA Deficiency | Treatment & Management | Point of Care
    https://www.statpearls.com/point-of-care/23356
    The worldwide prevalence of selective IgA deficiency depends on the ethnic background; it is most prevalent in White-race individuals. The incidence varies from 1:143 to 1:965 in different regions, with equal distribution between the genders. However, the real rate could be higher due to the absence of routine screening programs for immunodeficiencies and because many patients are asymptomatic. It is estimated that the prevalence of selective IgA deficiency is 38-fold higher in first-degree relatives of the patients with the disorder than unrelated donors, and the chance to inherit the disease in the family is about 20%. […] Selective IgA deficiency should be a possibility in every workup of an autoimmune disease.
  • #2 Selective IgA Deficiency – Immunology; Allergic Disorders – Merck Manual Professional Edition
    https://www.merckmanuals.com/professional/immunology-allergic-disorders/immunodeficiency-disorders/selective-iga-deficiency
    Selective IgA deficiency is an IgA level 7 mg/dL ( 70 mg/L, 0.4375 micromol/liter) with normal IgG and IgM levels. It is the most common primary immunodeficiency. […] Prevalence ranges from 1/100 to 1/1000 (1). […] The inheritance pattern is unknown, but having a family member with selective IgA deficiency increases the risk by approximately 50 times (2). […] Diagnosis of selective IgA deficiency is suspected in patients who have recurrent infections (including giardiasis); anaphylactic transfusion reactions; or a family history of common variable immunodeficiency (CVID), IgA deficiency, or autoimmune disorders or who are taking medications that lead to an acquired IgA deficiency. […] Confirm the diagnosis by measuring immunoglobulin levels and antibody titers after vaccines are given; an IgA level […] Avoid giving patients blood products or immune globulin that contain more than minimal amounts of IgA.
  • #3
    https://link.springer.com/article/10.1007/s10875-009-9357-x
    Selective IgA deficiency is considered as the most common primary immunodeficiency. The worldwide incidence varies depending on the ethnic background: 1:143 in the Arabian peninsula, 1:163 in Spain, 1:252 in Nigeria, 1:875 in England, and 1:965 in Brazil. The incidence is lower among Asian populations, e.g., from 1:2,600 to 1:5,300 in China and from 1:14,840 to 1:18,500 in Japan. In general, IgA deficiency is more common in Caucasians. In the USA, the frequency is estimated to be from 1:223 to 1:1,000 in community studies and from 1:333 to 1:3,000 among healthy blood donors. These numbers may in fact be higher because some individuals with IgA deficiency are asymptomatic, and there is no established routine screening program for IgA deficiency. The variation in incidence may also arise from the fact that the definition of selective IgA deficiency may differ in each study or registry.
  • #4
    https://link.springer.com/article/10.1007/s10875-009-9357-x
    Selective IgA deficiency is considered as the most common primary immunodeficiency. The worldwide incidence varies depending on the ethnic background: 1:143 in the Arabian peninsula, 1:163 in Spain, 1:252 in Nigeria, 1:875 in England, and 1:965 in Brazil. The incidence is lower among Asian populations, e.g., from 1:2,600 to 1:5,300 in China and from 1:14,840 to 1:18,500 in Japan. In general, IgA deficiency is more common in Caucasians. In the USA, the frequency is estimated to be from 1:223 to 1:1,000 in community studies and from 1:333 to 1:3,000 among healthy blood donors. These numbers may in fact be higher because some individuals with IgA deficiency are asymptomatic, and there is no established routine screening program for IgA deficiency. The variation in incidence may also arise from the fact that the definition of selective IgA deficiency may differ in each study or registry.
  • #5
    https://link.springer.com/article/10.1007/s10875-009-9357-x
    Selective IgA deficiency is considered as the most common primary immunodeficiency. The worldwide incidence varies depending on the ethnic background: 1:143 in the Arabian peninsula, 1:163 in Spain, 1:252 in Nigeria, 1:875 in England, and 1:965 in Brazil. The incidence is lower among Asian populations, e.g., from 1:2,600 to 1:5,300 in China and from 1:14,840 to 1:18,500 in Japan. In general, IgA deficiency is more common in Caucasians. In the USA, the frequency is estimated to be from 1:223 to 1:1,000 in community studies and from 1:333 to 1:3,000 among healthy blood donors. These numbers may in fact be higher because some individuals with IgA deficiency are asymptomatic, and there is no established routine screening program for IgA deficiency. The variation in incidence may also arise from the fact that the definition of selective IgA deficiency may differ in each study or registry.
  • #6 Frontiers | Innate Mechanisms in Selective IgA Deficiency
    https://www.frontiersin.org/journals/immunology/articles/10.3389/fimmu.2021.649112/full
    The prevalence of SIgAD is approximately in 1:700 individuals worldwide with a range from 1:134 to 1:18,500 depending on the population analyzed. […] However the prevalence of SIgAD varies with different ethnic background and global location and is highest in European descendants and Caucasians and lowest in oriental and Asian populations. […] The overall prevalence of SIgAD differs between 1:173 (in Sweden in 2009) and 1:3024 individuals (in the USA in 1969). […] However, the prevalence of SIgAD may be underestimated because there are many SIgAD individuals without having clinical symptoms. […] The variation in the prevalence of SIgAD may also result from the use of non-uniform study designs in the different countries by including individuals with a specific illness and thereby not reflecting the prevalence of the entire population. […] A rapid antibody test has become available that allows for population-based screening to diagnose selective IgA deficiency already in young children.
  • #7 Immunoglobulin A Deficiency: Background, Pathophysiology, Epidemiology
    https://emedicine.medscape.com/article/136580-overview
    At a minimum, an estimated 250,000 individuals have immunoglobulin A deficiency (IgAD) in the United States. […] In African Americans, the prevalence of IgAD is 1 case per 6000 persons. IgA levels are estimated to be abnormally low in 1:500 subjects, with the incidence as high as 1:100 atopic individuals. Complete absence of IgA is less frequent. […] Factors associated with the prevalence of IgAD include a family history of IgAD and the country of origin. Family studies using IgAD blood donors as probands show that first-degree relatives have a 7.5% prevalence rate of IgAD, which is 38-fold higher than that of unrelated donors. […] The serological prevalence of IgAD varies 100-fold among populations. […] IgAD is more frequent in adult subjects with chronic lung disease than in a healthy, age-matched control subjects.
  • #8 Selective IgA Deficiency | Treatment & Management | Point of Care
    https://www.statpearls.com/point-of-care/23356
    The worldwide prevalence of selective IgA deficiency depends on the ethnic background; it is most prevalent in White-race individuals. The incidence varies from 1:143 to 1:965 in different regions, with equal distribution between the genders. However, the real rate could be higher due to the absence of routine screening programs for immunodeficiencies and because many patients are asymptomatic. It is estimated that the prevalence of selective IgA deficiency is 38-fold higher in first-degree relatives of the patients with the disorder than unrelated donors, and the chance to inherit the disease in the family is about 20%. […] Selective IgA deficiency should be a possibility in every workup of an autoimmune disease.
  • #9 Frontiers | Innate Mechanisms in Selective IgA Deficiency
    https://www.frontiersin.org/journals/immunology/articles/10.3389/fimmu.2021.649112/full
    The prevalence of SIgAD is approximately in 1:700 individuals worldwide with a range from 1:134 to 1:18,500 depending on the population analyzed. […] However the prevalence of SIgAD varies with different ethnic background and global location and is highest in European descendants and Caucasians and lowest in oriental and Asian populations. […] The overall prevalence of SIgAD differs between 1:173 (in Sweden in 2009) and 1:3024 individuals (in the USA in 1969). […] However, the prevalence of SIgAD may be underestimated because there are many SIgAD individuals without having clinical symptoms. […] The variation in the prevalence of SIgAD may also result from the use of non-uniform study designs in the different countries by including individuals with a specific illness and thereby not reflecting the prevalence of the entire population. […] A rapid antibody test has become available that allows for population-based screening to diagnose selective IgA deficiency already in young children.
  • #10 Frontiers | Innate Mechanisms in Selective IgA Deficiency
    https://www.frontiersin.org/journals/immunology/articles/10.3389/fimmu.2021.649112/full
    The prevalence of SIgAD is approximately in 1:700 individuals worldwide with a range from 1:134 to 1:18,500 depending on the population analyzed. […] However the prevalence of SIgAD varies with different ethnic background and global location and is highest in European descendants and Caucasians and lowest in oriental and Asian populations. […] The overall prevalence of SIgAD differs between 1:173 (in Sweden in 2009) and 1:3024 individuals (in the USA in 1969). […] However, the prevalence of SIgAD may be underestimated because there are many SIgAD individuals without having clinical symptoms. […] The variation in the prevalence of SIgAD may also result from the use of non-uniform study designs in the different countries by including individuals with a specific illness and thereby not reflecting the prevalence of the entire population. […] A rapid antibody test has become available that allows for population-based screening to diagnose selective IgA deficiency already in young children.
  • #11
    https://link.springer.com/article/10.1007/s10875-009-9357-x
    Selective IgA deficiency is considered as the most common primary immunodeficiency. The worldwide incidence varies depending on the ethnic background: 1:143 in the Arabian peninsula, 1:163 in Spain, 1:252 in Nigeria, 1:875 in England, and 1:965 in Brazil. The incidence is lower among Asian populations, e.g., from 1:2,600 to 1:5,300 in China and from 1:14,840 to 1:18,500 in Japan. In general, IgA deficiency is more common in Caucasians. In the USA, the frequency is estimated to be from 1:223 to 1:1,000 in community studies and from 1:333 to 1:3,000 among healthy blood donors. These numbers may in fact be higher because some individuals with IgA deficiency are asymptomatic, and there is no established routine screening program for IgA deficiency. The variation in incidence may also arise from the fact that the definition of selective IgA deficiency may differ in each study or registry.
  • #12 Selective IgA Deficiency | Treatment & Management | Point of Care
    https://www.statpearls.com/point-of-care/23356
    The worldwide prevalence of selective IgA deficiency depends on the ethnic background; it is most prevalent in White-race individuals. The incidence varies from 1:143 to 1:965 in different regions, with equal distribution between the genders. However, the real rate could be higher due to the absence of routine screening programs for immunodeficiencies and because many patients are asymptomatic. It is estimated that the prevalence of selective IgA deficiency is 38-fold higher in first-degree relatives of the patients with the disorder than unrelated donors, and the chance to inherit the disease in the family is about 20%. […] Selective IgA deficiency should be a possibility in every workup of an autoimmune disease.
  • #13 Immunoglobulin A Deficiency: Background, Pathophysiology, Epidemiology
    https://emedicine.medscape.com/article/136580-overview
    At a minimum, an estimated 250,000 individuals have immunoglobulin A deficiency (IgAD) in the United States. […] In African Americans, the prevalence of IgAD is 1 case per 6000 persons. IgA levels are estimated to be abnormally low in 1:500 subjects, with the incidence as high as 1:100 atopic individuals. Complete absence of IgA is less frequent. […] Factors associated with the prevalence of IgAD include a family history of IgAD and the country of origin. Family studies using IgAD blood donors as probands show that first-degree relatives have a 7.5% prevalence rate of IgAD, which is 38-fold higher than that of unrelated donors. […] The serological prevalence of IgAD varies 100-fold among populations. […] IgAD is more frequent in adult subjects with chronic lung disease than in a healthy, age-matched control subjects.
  • #14 Immunoglobulin A Deficiency: Background, Pathophysiology, Epidemiology
    https://emedicine.medscape.com/article/136580-overview
    At a minimum, an estimated 250,000 individuals have immunoglobulin A deficiency (IgAD) in the United States. […] In African Americans, the prevalence of IgAD is 1 case per 6000 persons. IgA levels are estimated to be abnormally low in 1:500 subjects, with the incidence as high as 1:100 atopic individuals. Complete absence of IgA is less frequent. […] Factors associated with the prevalence of IgAD include a family history of IgAD and the country of origin. Family studies using IgAD blood donors as probands show that first-degree relatives have a 7.5% prevalence rate of IgAD, which is 38-fold higher than that of unrelated donors. […] The serological prevalence of IgAD varies 100-fold among populations. […] IgAD is more frequent in adult subjects with chronic lung disease than in a healthy, age-matched control subjects.
  • #15 Selective IgA Deficiency | Treatment & Management | Point of Care
    https://www.statpearls.com/point-of-care/23356
    The worldwide prevalence of selective IgA deficiency depends on the ethnic background; it is most prevalent in White-race individuals. The incidence varies from 1:143 to 1:965 in different regions, with equal distribution between the genders. However, the real rate could be higher due to the absence of routine screening programs for immunodeficiencies and because many patients are asymptomatic. It is estimated that the prevalence of selective IgA deficiency is 38-fold higher in first-degree relatives of the patients with the disorder than unrelated donors, and the chance to inherit the disease in the family is about 20%. […] Selective IgA deficiency should be a possibility in every workup of an autoimmune disease.
  • #16 Selective IgA deficiency | Immune Deficiency Foundation
    https://primaryimmune.org/understanding-primary-immunodeficiency/types-of-pi/selective-iga-deficiency
    Individuals with selective IgA deficiency (SIgAD) lack immunoglobulin A (IgA), but they usually have normal amounts of IgG and IgM. […] SIgAD is relatively common in people of European descent and rare in people of Asian descent. In North America, it is the most common form of primary immunodeficiency (PI), estimated to affect 1 in 500 people. […] Genetic susceptibility in IgA deficiency is not well defined, but familial inheritance of SIgAD may occur in approximately 20% of cases. SIgAD is also observed in families with common variable immune deficiency (CVID). […] The diagnosis of SIgAD is usually suspected because of chronic or recurrent ear infections, sinusitis, respiratory tract infections, chronic diarrhea, or some combination of these problems. […] The healthcare provider may order several other tests including autoantibodies.
  • #17 Selective IgA deficiency | Immune Deficiency Foundation
    https://primaryimmune.org/understanding-primary-immunodeficiency/types-of-pi/selective-iga-deficiency
    Individuals with selective IgA deficiency (SIgAD) lack immunoglobulin A (IgA), but they usually have normal amounts of IgG and IgM. […] SIgAD is relatively common in people of European descent and rare in people of Asian descent. In North America, it is the most common form of primary immunodeficiency (PI), estimated to affect 1 in 500 people. […] Genetic susceptibility in IgA deficiency is not well defined, but familial inheritance of SIgAD may occur in approximately 20% of cases. SIgAD is also observed in families with common variable immune deficiency (CVID). […] The diagnosis of SIgAD is usually suspected because of chronic or recurrent ear infections, sinusitis, respiratory tract infections, chronic diarrhea, or some combination of these problems. […] The healthcare provider may order several other tests including autoantibodies.
  • #18 Selective immunoglobulin A deficiency – wikidoc
    https://www.wikidoc.org/index.php/Selective_immunoglobulin_A_deficiency
    Selective IgA deficiency is the most common primary immunodeficiency. It is more common in caucasians with the prevalence rate of 167/100,000. The incidence of selective IgA deficiency differ based on the ethnic background. […] High prevalence rate of SIgAD was observed in first degree relatives of symptomatic SIgAD patient with consanguineous marriages. […] As high rate of familial inheritance is in families with SIgAD, screening in first-degree relatives of such patients may be performed.
  • #19 Selective IgA Deficiency in Autoimmune Diseases | Molecular Medicine | Full Text
    https://molmed.biomedcentral.com/articles/10.2119/molmed.2011.00195
    Selective immunoglobulin A deficiency (IgAD) is the most common primary immunodeficiency in Caucasians. […] The prevalence in various ethnic groups ranges from 1:155 in Spain to 1:18,550 in Japan. […] Most individuals with IgAD are clinically asymptomatic, but the defect may be associated with recurrent respiratory and gastrointestinal tract infections/disorders, autoimmunity and allergies. […] Patients with IgAD are usually more prone to infections when concomitant IgG subclass deficiency is present. […] IgAD is strongly associated with the major histocompatibility complex (MHC) region, in particular with the human leukocyte antigen (HLA)-B8, DR3, DQ2 haplotype, and up to 45% of IgAD patients have at least one copy of this haplotype compared to 16% in the general population. […] Other haplotypes, including HLA-DR7, DQ2 and DR1, DQ5 are also associated with IgAD.
  • #20 Selective IgA Deficiency in Autoimmune Diseases | Molecular Medicine | Full Text
    https://molmed.biomedcentral.com/articles/10.2119/molmed.2011.00195
    Interestingly, the ancestral 8.1 haplotype is also reported to be associated with Graves disease (GD), systemic lupus erythematosus (SLE), type 1 diabetes (T1D) and celiac disease (CD). […] Moreover, there are several non-MHC genes in common that have also been shown to be associated with these autoimmune disorders. […] Previous studies have reported an increased frequency of IgAD among SLE patients, ranging from 1:19 in the USA to 1:130 in Spain. […] We thus determined the frequency of IgAD among 3388 SLE patients in Sweden, the UK, the USA and China, using an enzyme-linked immunosorbent assay to measure the serum IgA levels. […] The prevalence of IgAD in T1D has been reported to range from 1:27 to 1:261 in several reports, although no cases were observed in three studies, indicating an increased frequency compared to the general population.
  • #21 Selective immunoglobulin A deficiency – Wikipedia
    https://en.wikipedia.org/wiki/Selective_immunoglobulin_A_deficiency
    Prevalence varies by population, but is on the order of 1 in 100 to 1 in 1000 people, making it relatively common. […] SIgAD occurs in 1 in 39 to 1 in 57 people with celiac disease. This is much higher than the prevalence of selective IgA deficiency in the general population. […] It is also significantly more common in those with type 1 diabetes. […] It is more common in males than in females.
  • #22 Selective IgA Deficiency in Autoimmune Diseases | Molecular Medicine | Full Text
    https://molmed.biomedcentral.com/articles/10.2119/molmed.2011.00195
    IgAD was previously shown to be associated with CD, with a reported overall prevalence of 1:39, indicating a 5- to 15-fold increase in the prevalence of IgAD among both children and adults with CD. […] We recently investigated the association between IgAD and CD in 442,225 individuals in Sweden, referred to immunology centers between 1998 and 2010 because of suspected CD. […] Altogether, 971 children and 1,338 adults with IgAD were identified, giving a frequency of 1:192. […] A common genetic background for selected autoimmune disorders, such as GD, SLE, T1D, CD and potentially MG and RA, involving both MHC and non-MHC encoded genes, has previously been suggested. […] In this report, we have added IgAD to this group of diseases, since it shows a markedly increased prevalence in GD, SLE, T1D and CD.
  • #23 Selective IgA Deficiency in Autoimmune Diseases | Molecular Medicine | Full Text
    https://molmed.biomedcentral.com/articles/10.2119/molmed.2011.00195
    IgAD was previously shown to be associated with CD, with a reported overall prevalence of 1:39, indicating a 5- to 15-fold increase in the prevalence of IgAD among both children and adults with CD. […] We recently investigated the association between IgAD and CD in 442,225 individuals in Sweden, referred to immunology centers between 1998 and 2010 because of suspected CD. […] Altogether, 971 children and 1,338 adults with IgAD were identified, giving a frequency of 1:192. […] A common genetic background for selected autoimmune disorders, such as GD, SLE, T1D, CD and potentially MG and RA, involving both MHC and non-MHC encoded genes, has previously been suggested. […] In this report, we have added IgAD to this group of diseases, since it shows a markedly increased prevalence in GD, SLE, T1D and CD.
  • #24 Selective IgA Deficiency in Autoimmune Diseases | Molecular Medicine | Full Text
    https://molmed.biomedcentral.com/articles/10.2119/molmed.2011.00195
    Interestingly, the ancestral 8.1 haplotype is also reported to be associated with Graves disease (GD), systemic lupus erythematosus (SLE), type 1 diabetes (T1D) and celiac disease (CD). […] Moreover, there are several non-MHC genes in common that have also been shown to be associated with these autoimmune disorders. […] Previous studies have reported an increased frequency of IgAD among SLE patients, ranging from 1:19 in the USA to 1:130 in Spain. […] We thus determined the frequency of IgAD among 3388 SLE patients in Sweden, the UK, the USA and China, using an enzyme-linked immunosorbent assay to measure the serum IgA levels. […] The prevalence of IgAD in T1D has been reported to range from 1:27 to 1:261 in several reports, although no cases were observed in three studies, indicating an increased frequency compared to the general population.
  • #25 Low IgA & Selective IgA Deficiency: Causes & Symptoms – SelfDecode Labs
    https://labs.selfdecode.com/blog/iga-deficiency/
    Patients with selective IgA deficiency (undetectable IgA but normal IgG and IgM levels) have a 10 to 20 times higher risk of celiac disease. […] Multiple studies report an increased prevalence of IgA deficiency in patients with celiac disease and increased prevalence of celiac disease in patients with IgA deficiency. […] People with IgA deficiency have a higher association of type 1 diabetes (up to 10 times), lupus, juvenile idiopathic arthritis, IBD (both Crohns and ulcerative colitis), rheumatoid arthritis, and thyroid disorders. […] Those with IgA deficiency have a moderately increased risk of cancer, especially gut cancer. […] This study was done as a cohort and showed risk increases in first year of follow up suggesting surveillance bias. More studies are needed to conclude degree of cancer risk.
  • #26 Selective immunoglobulin A deficiency in children with diabetes mellitus: Data from a medical center in Ukraine | PLOS One
    https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0277273
    The prevalence of selective IgA deficiency in children with DM in Ternopil region (Ukraine) is 2.9% (1:34), with its predominance in males (85.7%). Children with SIgAD and DM are at increased risk of autoimmune thyroiditis (42.9%). There was no history of recurrent infections in these patients. The study showed that patients with low IgA levels need further re-testing of IgA levels to exclude SIgAD. Children with SIgAD and DM should be monitored for autoimmune manifestations that may affect the course and consequences of the disease.
  • #27 Selective IgA Deficiency in Autoimmune Diseases | Molecular Medicine | Full Text
    https://molmed.biomedcentral.com/articles/10.2119/molmed.2011.00195
    Interestingly, the ancestral 8.1 haplotype is also reported to be associated with Graves disease (GD), systemic lupus erythematosus (SLE), type 1 diabetes (T1D) and celiac disease (CD). […] Moreover, there are several non-MHC genes in common that have also been shown to be associated with these autoimmune disorders. […] Previous studies have reported an increased frequency of IgAD among SLE patients, ranging from 1:19 in the USA to 1:130 in Spain. […] We thus determined the frequency of IgAD among 3388 SLE patients in Sweden, the UK, the USA and China, using an enzyme-linked immunosorbent assay to measure the serum IgA levels. […] The prevalence of IgAD in T1D has been reported to range from 1:27 to 1:261 in several reports, although no cases were observed in three studies, indicating an increased frequency compared to the general population.
  • #28 Immunoglobulin A Deficiency: Background, Pathophysiology, Epidemiology
    https://emedicine.medscape.com/article/136580-overview
    The 20-year longitudinal study of healthy blood donors with incidental findings of IgAD used questionnaires and medical record reviews and found a 3-fold increase in rates of severe childhood respiratory conditions (9% vs 3%), a 4-fold increase in rates of severe adult respiratory conditions (16% vs 4%), a similar increase in recurrent mild respiratory tract infections, and a significant increase in rates of recurrent viral infections (16% vs 1%). […] Another study demonstrated that a high proportion of patients with systemic lupus erythematosus (6%) were found to have IgAD compared to the general population. […] When IgAD is associated with one or more IgG subclass deficiencies or impaired polysaccharide responsiveness, some individuals with IgAD may develop recurrent sinopulmonary infections, especially in patients with concurrent IgG 2 and/or 4 subclass deficiency.
  • #29 The Epidemiology and Clinical Presentations of Atopic Diseases in Selective IgA Deficiency
    https://pmc.ncbi.nlm.nih.gov/articles/PMC8432128/
    Selective IgA deficiency (sIgAD) is the most common primary immunodeficiency disease (PID), with an estimated occurrence from about 1:3000 to even 1:150, depending on population. […] If symptomatic, sIgAD is connected to more frequent viral and bacterial infections of upper respiratory, urinary, and gastrointestinal tracts, as well as autoimmune and allergic diseases. […] It was suggested that allergic diseases (e.g., eczema, rhinitis, asthma) are more common in patients diagnosed with this particular PID, however, the prevalence and severity of allergic manifestations can be associated with ethnic background. […] The true prevalence of allergy among patients with sIgAD is still under debate since studies from different countries present inconsistent results. […] Most publications support the relationship between sIgAD or low-IgA levels and allergic diseases, but some researchers deny it.
  • #30 The Epidemiology and Clinical Presentations of Atopic Diseases in Selective IgA Deficiency
    https://pmc.ncbi.nlm.nih.gov/articles/PMC8432128/
    A similar observation has been done in Ankara more recently, in 2017, where 45.7% of the patients diagnosed with sIgAD presented one of the following: asthma, rhinitis, eczema, atopic dermatitis, and interestingly the prevalence of allergy in a close family of this patients rose up to 43.2%. […] The American Academy of Allergy, Asthma Immunology (AAAAI) and the American College of Allergy, Asthma Immunology (ACAAI) developed practice parameters to guide the management of primary immunodeficiencies. […] It is stated there that atopic diseases should be treated aggressively in patients with sIgAD. […] Our clinical experience shows that treating atopic diseases in patients with immunodeficiency is difficult and requires special attention and scrupulousness. […] In addition to the commonly used anti-histamine drugs, beta-mimetics, and glucocorticosteroids, in the case of treatment-resistant atopic diseases, biological drugs such as omalizumab and dupilumab might be helpful.
  • #31 Selective IgA Deficiency and Allergy: A Fresh Look to an Old Story
    https://www.mdpi.com/1648-9144/58/1/129
    Selective IgA deficiency (SIgAD) is the most common primary immune deficiency (PID). It is classified as a humoral PID characterized by isolated deficiency of IgA (less than 7 mg/dL but normal serum IgG and IgM) in subjects greater than 4 years of age. […] The incidence of SIgAD presents considerable variability when comparing different ethnic groups. In the Caucasian population SIgAD is the most common primitive humoral immunodeficiency with an incidence varying from 1:150 to 1:3000, while in Asian populations its incidence is significantly lower (1:4000 in China and up to 1:18,000 in Japan). […] Studies analyzing allergy on SIgAD patients showed prevalence up to 84%, supporting in most cases the relationship between sIgAD and allergic disease. […] The association between SIgAD and allergy was found for various allergic manifestations, the most commonly described of which are asthma, allergic rhinitis, allergic conjunctivitis, urticaria, atopic dermatitis and food allergy, even if the exact prevalence of each symptom and of one clinical manifestation or another varies among the studies reported.
  • #32 Immunoglobulin A Deficiency: Background, Pathophysiology, Epidemiology
    https://emedicine.medscape.com/article/136580-overview
    At a minimum, an estimated 250,000 individuals have immunoglobulin A deficiency (IgAD) in the United States. […] In African Americans, the prevalence of IgAD is 1 case per 6000 persons. IgA levels are estimated to be abnormally low in 1:500 subjects, with the incidence as high as 1:100 atopic individuals. Complete absence of IgA is less frequent. […] Factors associated with the prevalence of IgAD include a family history of IgAD and the country of origin. Family studies using IgAD blood donors as probands show that first-degree relatives have a 7.5% prevalence rate of IgAD, which is 38-fold higher than that of unrelated donors. […] The serological prevalence of IgAD varies 100-fold among populations. […] IgAD is more frequent in adult subjects with chronic lung disease than in a healthy, age-matched control subjects.
  • #33 Immunoglobulin A Deficiency: Background, Pathophysiology, Epidemiology
    https://emedicine.medscape.com/article/136580-overview
    The 20-year longitudinal study of healthy blood donors with incidental findings of IgAD used questionnaires and medical record reviews and found a 3-fold increase in rates of severe childhood respiratory conditions (9% vs 3%), a 4-fold increase in rates of severe adult respiratory conditions (16% vs 4%), a similar increase in recurrent mild respiratory tract infections, and a significant increase in rates of recurrent viral infections (16% vs 1%). […] Another study demonstrated that a high proportion of patients with systemic lupus erythematosus (6%) were found to have IgAD compared to the general population. […] When IgAD is associated with one or more IgG subclass deficiencies or impaired polysaccharide responsiveness, some individuals with IgAD may develop recurrent sinopulmonary infections, especially in patients with concurrent IgG 2 and/or 4 subclass deficiency.
  • #34 Immunoglobulin A Deficiency: Background, Pathophysiology, Epidemiology
    https://emedicine.medscape.com/article/136580-overview
    The 20-year longitudinal study of healthy blood donors with incidental findings of IgAD used questionnaires and medical record reviews and found a 3-fold increase in rates of severe childhood respiratory conditions (9% vs 3%), a 4-fold increase in rates of severe adult respiratory conditions (16% vs 4%), a similar increase in recurrent mild respiratory tract infections, and a significant increase in rates of recurrent viral infections (16% vs 1%). […] Another study demonstrated that a high proportion of patients with systemic lupus erythematosus (6%) were found to have IgAD compared to the general population. […] When IgAD is associated with one or more IgG subclass deficiencies or impaired polysaccharide responsiveness, some individuals with IgAD may develop recurrent sinopulmonary infections, especially in patients with concurrent IgG 2 and/or 4 subclass deficiency.
  • #35 Immunoglobulin A Deficiency: Background, Pathophysiology, Epidemiology
    https://emedicine.medscape.com/article/136580-overview
    The 20-year longitudinal study of healthy blood donors with incidental findings of IgAD used questionnaires and medical record reviews and found a 3-fold increase in rates of severe childhood respiratory conditions (9% vs 3%), a 4-fold increase in rates of severe adult respiratory conditions (16% vs 4%), a similar increase in recurrent mild respiratory tract infections, and a significant increase in rates of recurrent viral infections (16% vs 1%). […] Another study demonstrated that a high proportion of patients with systemic lupus erythematosus (6%) were found to have IgAD compared to the general population. […] When IgAD is associated with one or more IgG subclass deficiencies or impaired polysaccharide responsiveness, some individuals with IgAD may develop recurrent sinopulmonary infections, especially in patients with concurrent IgG 2 and/or 4 subclass deficiency.
  • #36 Immunoglobulin A Deficiency: Background, Pathophysiology, Epidemiology
    https://emedicine.medscape.com/article/136580-overview
    The 20-year longitudinal study of healthy blood donors with incidental findings of IgAD used questionnaires and medical record reviews and found a 3-fold increase in rates of severe childhood respiratory conditions (9% vs 3%), a 4-fold increase in rates of severe adult respiratory conditions (16% vs 4%), a similar increase in recurrent mild respiratory tract infections, and a significant increase in rates of recurrent viral infections (16% vs 1%). […] Another study demonstrated that a high proportion of patients with systemic lupus erythematosus (6%) were found to have IgAD compared to the general population. […] When IgAD is associated with one or more IgG subclass deficiencies or impaired polysaccharide responsiveness, some individuals with IgAD may develop recurrent sinopulmonary infections, especially in patients with concurrent IgG 2 and/or 4 subclass deficiency.
  • #37 Immunoglobulin A Deficiency: Background, Pathophysiology, Epidemiology
    https://emedicine.medscape.com/article/136580-overview
    The 20-year longitudinal study of healthy blood donors with incidental findings of IgAD used questionnaires and medical record reviews and found a 3-fold increase in rates of severe childhood respiratory conditions (9% vs 3%), a 4-fold increase in rates of severe adult respiratory conditions (16% vs 4%), a similar increase in recurrent mild respiratory tract infections, and a significant increase in rates of recurrent viral infections (16% vs 1%). […] Another study demonstrated that a high proportion of patients with systemic lupus erythematosus (6%) were found to have IgAD compared to the general population. […] When IgAD is associated with one or more IgG subclass deficiencies or impaired polysaccharide responsiveness, some individuals with IgAD may develop recurrent sinopulmonary infections, especially in patients with concurrent IgG 2 and/or 4 subclass deficiency.
  • #38 Relationship between Selective IgA Deficiency and COVID-19 Prognosis
    https://www.jstage.jst.go.jp/article/yoken/75/3/75_JJID.2021.281/_article
    The prevalence and mortality rates of coronavirus disease 2019 (COVID-19) widely vary among populations. […] We explored the relationship between selective IgA deficiency (SIgAD) and COVID-19 severity. […] Eleven patients had SIgAD. […] The relationship between SIgAD and severe COVID-19 infection was explored using logistic regression analysis. […] In the univariate logistic regression analysis, the risk of severe COVID-19 disease in patients with SIgAD was approximately 7.7-fold higher than that in other patients (odds ratio [OR], 7.789; 95% confidence interval [CI], 1.66536.690, P= 0.008), while it was 4-fold (OR, 4.053; 95% CI, 1.18213.903,P = 0.026) higher in the multivariate logistic regression analysis. […] In patients with SIgAD, the number of severe acute respiratory coronaviruses 2 that pass through mucosal membranes may be increased, leading to complications such as cytokine storm syndrome and acute respiratory distress syndrome.
  • #39 The Epidemiology and Clinical Presentations of Atopic Diseases in Selective IgA Deficiency
    https://pmc.ncbi.nlm.nih.gov/articles/PMC8432128/
    The importance of the IgA was raised again because of the ongoing global pandemic of coronavirus disease 2019 (COVID-19). […] The prevalence of sIgAD differs in various countries and the same was found for COVID-19. […] Researchers also point to the risk of a poor response against SARS-CoV-2 after immunization in this group of patients.
  • #40 Relationship between Selective IgA Deficiency and COVID-19 Prognosis
    https://www.jstage.jst.go.jp/article/yoken/75/3/75_JJID.2021.281/_article
    The prevalence and mortality rates of coronavirus disease 2019 (COVID-19) widely vary among populations. […] We explored the relationship between selective IgA deficiency (SIgAD) and COVID-19 severity. […] Eleven patients had SIgAD. […] The relationship between SIgAD and severe COVID-19 infection was explored using logistic regression analysis. […] In the univariate logistic regression analysis, the risk of severe COVID-19 disease in patients with SIgAD was approximately 7.7-fold higher than that in other patients (odds ratio [OR], 7.789; 95% confidence interval [CI], 1.66536.690, P= 0.008), while it was 4-fold (OR, 4.053; 95% CI, 1.18213.903,P = 0.026) higher in the multivariate logistic regression analysis. […] In patients with SIgAD, the number of severe acute respiratory coronaviruses 2 that pass through mucosal membranes may be increased, leading to complications such as cytokine storm syndrome and acute respiratory distress syndrome.
  • #41 Frontiers | Innate Mechanisms in Selective IgA Deficiency
    https://www.frontiersin.org/journals/immunology/articles/10.3389/fimmu.2021.649112/full
    Selective IgA deficiency (SIgAD), characterized by a serum IgA level below 0.07 mg/ml, while displaying normal serum levels of IgM and IgG antibodies, is the most frequently occurring primary immunodeficiency that reveals itself after the first four years after birth. […] However, recent studies show that newborns and young infants already display clinical manifestations of this condition due to aberrancies in their immune defense. […] Interestingly, there is a huge heterogeneity in the clinical symptoms of the affected individuals. More than 50% of the affected individuals do not have clinical symptoms, while the individuals that do show clinical symptoms can suffer from mild to severe infections, allergies and autoimmune diseases. […] However, the reason for this heterogeneity in the manifestation of clinical symptoms of the individuals with SIgAD is unknown. […] Therefore, this review focusses on the characteristics of innate immune system driving T-cell independent IgA production and providing a mechanism underlying the development of SIgAD. […] Currently, no specific treatment for SIgAD exists and novel therapeutic strategies could be developed based on the discussed information.
  • #42 Low IgA & Selective IgA Deficiency: Causes & Symptoms – SelfDecode Labs
    https://labs.selfdecode.com/blog/iga-deficiency/
    Low IgA can be caused by selective IgA deficiency, when only IgA levels are low but other antibodies (IgG, IgM, IgD, and IgE) are normal. […] Selective IgA deficiency can be inherited or occur spontaneously (due to infections, medication, or unknown causes). The genetic disorder that causes people to lack IgA is found in up to 1% of the population. […] IgA deficiency is the most common primary immunodeficiency. Prevalence is higher in whites (1:155 in Spain, around 1:500 in general) and lower in Asians (1:18550 in Japan). […] People are IgA deficient if they have blood IgA levels below 7 mg/dL with normal IgM and IgG levels. […] Eighty-five to 90% of people with IgA deficiency have no symptoms. Those with symptoms usually have respiratory or gut infections. […] IgA-deficient people have a tendency to develop infections and disorders of the gut, such as malabsorption, lactose intolerance, celiac disease, and ulcerative colitis.
  • #43 Frontiers | Innate Mechanisms in Selective IgA Deficiency
    https://www.frontiersin.org/journals/immunology/articles/10.3389/fimmu.2021.649112/full
    The prevalence of SIgAD is approximately in 1:700 individuals worldwide with a range from 1:134 to 1:18,500 depending on the population analyzed. […] However the prevalence of SIgAD varies with different ethnic background and global location and is highest in European descendants and Caucasians and lowest in oriental and Asian populations. […] The overall prevalence of SIgAD differs between 1:173 (in Sweden in 2009) and 1:3024 individuals (in the USA in 1969). […] However, the prevalence of SIgAD may be underestimated because there are many SIgAD individuals without having clinical symptoms. […] The variation in the prevalence of SIgAD may also result from the use of non-uniform study designs in the different countries by including individuals with a specific illness and thereby not reflecting the prevalence of the entire population. […] A rapid antibody test has become available that allows for population-based screening to diagnose selective IgA deficiency already in young children.
  • #44 Medical Science Monitor | Population-Based Screening for Selective Immunoglobulin A (IgA) Deficiency in Lithuanian Children Using a Rapid Antibody-Based Fingertip Test – Article abstract #898269
    https://medscimonit.com/abstract/index/idArt/898269
    BACKGROUND: Selective immunoglobulin A (IgA) deficiency is the most common inherited immunodeficiency disorder worldwide. An early diagnosis is advocated because of the increased risk of infections, autoimmune diseases, and allergic reactions. We investigated the usefulness of a rapid point-of-care test in detecting for IgA deficiency in a population with a previously unknown prevalence. […] RESULTS: IgA deficiency was suspected in one girl and in three boys on the basis of the rapid test, and the diagnosis was confirmed for all four cases (prevalence 0.4%, 95% confidence interval 0.16–1.02%). […] CONCLUSIONS: The rapid antibody test is a practical and accurate method to diagnose selective IgA deficiency in children. The prevalence of IgA deficiency among Lithuanian schoolchildren is 1:250.
  • #45 Anaphylactic transfusion reactions and IgA deficiency | Professional Education
    https://professionaleducation.blood.ca/en/transfusion/publications/anaphylactic-transfusion-reactions-and-iga-deficiency
    IgA deficiency is the most common human immunodeficiency. […] From a transfusion medicine perspective, the presence of anti-IgA in an IgA deficient recipient is a possible cause of anaphylactic transfusion reactions. Approximately 1 to 5% of anaphylactic transfusion reactions in a Caucasian population may be associated with anti-IgA in IgA deficient recipients. […] If a patient develops an anaphylactic transfusion reaction, a comprehensive assessment should be performed to assess both transfusion-related and unrelated causes of anaphylaxis. […] Depending on the clinical scenario, screening tests may include immunoglobulin quantification for IgA levels as well as haptoglobin levels. […] At Canadian Blood Services, screening of approximately 100,000 donor samples identified 139 donors with confirmed IgA levels 0.05 mg/dL.
  • #46 Anaphylactic transfusion reactions and IgA deficiency | Professional Education
    https://professionaleducation.blood.ca/en/transfusion/publications/anaphylactic-transfusion-reactions-and-iga-deficiency
    In the Canadian Blood Services donor screening program, anti-IgA antibodies were identified in 41% of severely deficient donors. […] At Canadian Blood Services, from 0 to 4 anaphylactic transfusion reactions that occur each year are likely related to anti-IgA antibodies. […] If the frequency of IgA deficiency and anti-IgA is similar in recipients and in donors, one would expect that approximately 1 to 1.6 patients in 1,000 in Canada would be IgA deficient with anti-IgA. However, the frequency of anaphylactic transfusion reactions related to anti-IgA is less than 1 in 500,000 components transfused annually. […] Hence, even in the presence of anti-IgA antibodies in the recipient, risk of severe allergic or anaphylactic transfusion reaction is low.
  • #47 Immunoglobulin A Deficiency: Background, Pathophysiology, Epidemiology
    https://emedicine.medscape.com/article/136580-overview
    The incidence of cancer among 562 Danish and Swedish subjects with CVID or IgA was compared with that of 2017 relatives for the period 19581996. […] The prevalence rate of IgG anti-IgA antibodies among white persons with IgAD is 30-40%. […] A recent case report described the successful management of an SIgAD patient who required massive blood transfusion during emergency cesarean delivery. […] GI tract infections, including chronic or recurrent giardiasis and other disorders, are reported with increased frequency. […] An area of ongoing research is the relationship between COVID-19 and SIgAD. Data has shown the risk of severe COVID-19 disease in patients with SIgAD was approximately 7.7-fold higher than that in other patients. […] Quality of life (QOL) studies address the cumulative impact of living with a chronic disease such as SIgAD. Several standardized scales were administered to all patients with primary antibody deficiencies seen by a single Norwegian hospital. Low QOL scores were related to unemployment, infections in more than 4 organs, and more than 2 additional diseases. Persons with SIgAD had significantly higher QOL index scores than those with other antibody deficiencies.
  • #48 Understanding the natural history of selective IgA deficiency | Jornal de Pediatria
    https://jped.elsevier.es/en-understanding-natural-history-selective-iga-avance-S0021755725000658
    SIgAD is a clinically significant condition. Understanding its natural history deepens our knowledge of the disease and helps early detection and diagnosis of comorbidities that may arise at various stages of a patient’s life. Monitoring other immunoglobulin levels may offer potential biomarkers for predicting autoimmune conditions; however, larger studies are needed to validate these biomarkers. […] SIgAD is the most prevalent IEI, with prevalence rates among blood donors varying from 1:163 in Spain and 1:143 in the Arabian Peninsula to 1:4100 in China and 1:18,550 in Japan, suggesting a lower prevalence among Asian populations. […] The follow-up of patients with SIgAD presents several challenges: they may exhibit extremely variable phenotypes, ranging from entirely asymptomatic to mild or severe infections, allergies, and autoimmune diseases. In this study, during at least five years of follow-up after the diagnosis of SIgAD, it was observed with statistical significance that the ages of onset for infections, allergies, and autoimmune diseases were variable.
  • #49 Understanding the natural history of selective IgA deficiency | Jornal de Pediatria
    https://jped.elsevier.es/en-understanding-natural-history-selective-iga-avance-S0021755725000658
    Understanding the natural history of patients with SIgAD deepens the comprehension of the disease and helps early awareness and diagnosis of comorbidities that may arise at different stages of the patient’s life. Regular monitoring of IgA levels is necessary, with attention to the potential for normalization; however, ongoing follow-up is crucial due to the risk of progression to other immunodeficiencies, the development of autoimmune diseases, and vigilance for neoplasms. Additionally, monitoring other immunoglobulins may aid in identifying potential biomarkers for autoimmunity, though further studies are needed to validate these biomarkers.
  • #50 Common Variable Immunodeficiency and Selective IgA Deficiency: Focus on Autoimmune Manifestations and Their Pathogenesis
    https://www.mdpi.com/2673-8937/3/4/31
    Selective IgA deficiency is the most frequent cause of primary immunodeficiencies, as defined by the European Society for Immunodeficiencies (ESID) and classified by the International Union of Immunological Societies Expert Committee. […] The prevalence varies between 1:100 and 1:1000 depending on the population and can be approximated at around 1:600 in Caucasians. In general, it is more common in Caucasians and is rarest in Japan and China; however, these data lack precision, given the different cut-off levels of serum IgA chosen in each different registry or study. Of note, underdiagnosis is to be expected due to the high prevalence of the asymptomatic phenotype coupled with the absence of routine screening programs for SIgAD.
  • #51 Selective IgA Deficiency in Autoimmune Diseases | Molecular Medicine | Full Text
    https://molmed.biomedcentral.com/articles/10.2119/molmed.2011.00195
    IgAD was previously shown to be associated with CD, with a reported overall prevalence of 1:39, indicating a 5- to 15-fold increase in the prevalence of IgAD among both children and adults with CD. […] We recently investigated the association between IgAD and CD in 442,225 individuals in Sweden, referred to immunology centers between 1998 and 2010 because of suspected CD. […] Altogether, 971 children and 1,338 adults with IgAD were identified, giving a frequency of 1:192. […] A common genetic background for selected autoimmune disorders, such as GD, SLE, T1D, CD and potentially MG and RA, involving both MHC and non-MHC encoded genes, has previously been suggested. […] In this report, we have added IgAD to this group of diseases, since it shows a markedly increased prevalence in GD, SLE, T1D and CD.
  • #52 The Epidemiology and Clinical Presentations of Atopic Diseases in Selective IgA Deficiency
    https://pmc.ncbi.nlm.nih.gov/articles/PMC8432128/
    Selective IgA deficiency (sIgAD) is the most common primary immunodeficiency disease (PID), with an estimated occurrence from about 1:3000 to even 1:150, depending on population. […] If symptomatic, sIgAD is connected to more frequent viral and bacterial infections of upper respiratory, urinary, and gastrointestinal tracts, as well as autoimmune and allergic diseases. […] It was suggested that allergic diseases (e.g., eczema, rhinitis, asthma) are more common in patients diagnosed with this particular PID, however, the prevalence and severity of allergic manifestations can be associated with ethnic background. […] The true prevalence of allergy among patients with sIgAD is still under debate since studies from different countries present inconsistent results. […] Most publications support the relationship between sIgAD or low-IgA levels and allergic diseases, but some researchers deny it.
  • #53 Frontiers | Innate Mechanisms in Selective IgA Deficiency
    https://www.frontiersin.org/journals/immunology/articles/10.3389/fimmu.2021.649112/full
    The prevalence of SIgAD is approximately in 1:700 individuals worldwide with a range from 1:134 to 1:18,500 depending on the population analyzed. […] However the prevalence of SIgAD varies with different ethnic background and global location and is highest in European descendants and Caucasians and lowest in oriental and Asian populations. […] The overall prevalence of SIgAD differs between 1:173 (in Sweden in 2009) and 1:3024 individuals (in the USA in 1969). […] However, the prevalence of SIgAD may be underestimated because there are many SIgAD individuals without having clinical symptoms. […] The variation in the prevalence of SIgAD may also result from the use of non-uniform study designs in the different countries by including individuals with a specific illness and thereby not reflecting the prevalence of the entire population. […] A rapid antibody test has become available that allows for population-based screening to diagnose selective IgA deficiency already in young children.

Zobacz więcej

nawracająca infekcja dróg oddechowych pierwotny niedobór odporności pokrzywka pospolity zmienny niedobór odporności młodzieńcze idiopatyczne zapalenie stawów pochodzenie etniczne haplotyp HLA alergiczny nieżyt nosa choroby tarczycy burza cytokinowa choroba trzewna astma cukrzyca typu 1 alergia pokarmowa selektywny niedobór IgA celiakia bielactwo reumatoidalne zapalenie stawów zespół ostrej niewydolności oddechowej zapalne choroby jelit ludzki antygen leukocytarny atopowe zapalenie skóry choroba Gravesa-Basedowa główny kompleks zgodności tkankowej toczeń rumieniowaty układowy przeciwciało anty-IgA alergiczne zapalenie spojówek