Reaktywne zapalenie stawów
Epidemiologia

Reaktywne zapalenie stawów (ReA) jest rzadką spondyloartropatią seronegatywną o zróżnicowanej epidemiologii, z zapadalnością od 0,6 do 27 przypadków na 100 000 osób, zależnie od regionu i populacji. Najczęściej dotyka dorosłych w wieku 15-40 lat, z przewagą mężczyzn (stosunek 4:1), szczególnie po zakażeniach układu moczowo-płciowego (np. Chlamydia trachomatis) oraz przewodu pokarmowego (Salmonella, Shigella, Yersinia). Antygen HLA-B27 występuje u 50-80% pacjentów z ReA i wiąże się z cięższym przebiegiem choroby, częstszymi objawami pozastawowymi oraz dłuższym czasem trwania. Ryzyko rozwoju ReA po zakażeniu bakteryjnym wynosi 2-4% po infekcjach układu moczowo-płciowego i do 15% po zakażeniach przewodu pokarmowego, z wyższym ryzykiem u pacjentów HIV-dodatnich i nosicieli HLA-B27.

Epidemiologia reaktywnego zapalenia stawów

Reaktywne zapalenie stawów (ReA) stanowi rzadką formę zapalnej choroby stawów, klasyfikowaną w grupie spondyloartropatii seronegatywnych. Częstość występowania tego schorzenia jest stosunkowo niska, a dane epidemiologiczne wskazują na zróżnicowaną zapadalność w różnych populacjach.12

Zapadalność i chorobowość

Według badań populacyjnych, zapadalność na reaktywne zapalenie stawów wynosi od 0,6 do 27 przypadków na 100 000 osób.1 Inne źródła podają zakres 3,5-5 przypadków na 100 000 mieszkańców w Stanach Zjednoczonych.34 W badaniu przeprowadzonym wśród personelu marynarki wojennej USA w okresie 10 lat odnotowano zapadalność na poziomie 4 przypadków na 100 000 mężczyzn rocznie.3

Chorobowość szacuje się na około 30-40 przypadków na 100 000 osób na całym świecie.56 Niektórzy badacze sugerują, że częstość występowania może być niedoszacowana ze względu na trudności diagnostyczne, różnorodność manifestacji klinicznych oraz różnice geograficzne i genetyczne.7

Zróżnicowanie geograficzne

Dane epidemiologiczne dotyczące reaktywnego zapalenia stawów różnią się w zależności od położenia geograficznego:8

  • W Norwegii roczna zapadalność wynosiła 4,6 przypadków na 100 000 osób dla ReA związanego z infekcją chlamydią oraz 5 przypadków na 100 000 dla ReA wywołanego przez bakterie jelitowe (1988-1990)910
  • W Finlandii roczna zapadalność wynosiła 43,6 przypadków na 100 000 (dane z 1978 roku)10
  • W Wielkiej Brytanii zapadalność na ReA po zapaleniu cewki moczowej wynosi około 0,8%9
  • W Republice Czeskiej roczna zapadalność u dorosłych w latach 2002-2003 wynosiła 9,3 przypadków na 100 000 osób9

Zakażenia wywołujące reaktywne zapalenie stawów mogą się różnić w zależności od lokalizacji geograficznej. Na przykład, Yersinia enterocolitica jest częściej identyfikowana w Europie niż w Ameryce Północnej, przez co jest odpowiedzialna za więcej przypadków ReA w krajach takich jak Finlandia i Norwegia.8

Czynniki ryzyka, wiek i płeć

Reaktywne zapalenie stawów najczęściej występuje u osób dorosłych w wieku 15-40 lat, ze szczególnym nasileniem w drugiej i trzeciej dekadzie życia.11112 Choroba jest rzadko spotykana u małych dzieci, choć może wystąpić u nastolatków oraz u dzieci w wieku 6-14 lat po zakażeniach przewodu pokarmowego wywołanych przez Clostridium difficile.1314

Obserwuje się różnice w podatności na chorobę w zależności od płci:15

  • Po zakażeniach układu moczowo-płciowego ReA częściej występuje u mężczyzn (stosunek mężczyzn do kobiet wynosi 9:1)1516
  • Po zakażeniach przewodu pokarmowego ReA dotyka mężczyzn i kobiety z podobną częstością (stosunek 1:1)1512

Ogólnie, u mężczyzn reaktywne zapalenie stawów diagnozuje się częściej niż u kobiet z szacowanym stosunkiem 4:1, choć niektórzy badacze sugerują, że u kobiet schorzenie to może być niedodiagnozowane.510

Predyspozycje genetyczne

Antygen HLA-B27 jest głównym czynnikiem genetycznym predysponującym do rozwoju reaktywnego zapalenia stawów. Szacuje się, że 50-80% pacjentów z ReA posiada ten allel, w porównaniu do około 7-8% populacji ogólnej.17186

Występowanie ReA wydaje się być związane z częstością występowania antygenu HLA-B27 w danej populacji oraz z częstością występowania zapalenia cewki moczowej/szyjki macicy i biegunki zakaźnej.8 Obecność HLA-B27 wiąże się z:

  • Cięższym przebiegiem zapalenia stawów17
  • Częstszym występowaniem objawów pozastawowych17
  • Dłuższym czasem trwania choroby17
  • 20-25% ryzykiem rozwoju ReA po bakteryjnym zapaleniu jelit u osób z HLA-B27, w porównaniu do 1-4% w populacji ogólnej3

Zakażenia inicjujące

Reaktywne zapalenie stawów jest wywoływane przez zakażenia bakteryjne, szczególnie dotyczące układu moczowo-płciowego lub przewodu pokarmowego. Najczęstsze patogeny inicjujące obejmują:119

Zakażenia układu moczowo-płciowego:

Zakażenia przewodu pokarmowego:

Zapadalność po zakażeniach

Ryzyko wystąpienia reaktywnego zapalenia stawów różni się w zależności od typu zakażenia:120

  • Po zakażeniu układu moczowo-płciowego: 2-4%, głównie po zakażeniu Chlamydia trachomatis12
  • Po zakażeniach przewodu pokarmowego: 0-15% po zakażeniach Salmonella, Shigella, Campylobacter lub Yersinia12
  • 1-3% pacjentów z niespecyficznym zapaleniem cewki moczowej rozwija epizod zapalenia stawów12
  • 12% przypadków po nierzeżączkowym zapaleniu cewki moczowej2122
  • 0,21% po ogniskach bakteryjnej czerwonki2122

Szczegółowe dane dotyczące zapadalności po poszczególnych zakażeniach:520

  • Po zakażeniu Campylobacter: 900 na 100 000 przypadków (9 przypadków na 1000 zakażeń)520
  • Po zakażeniu Salmonella i Shigella: 1200 na 100 000 przypadków (12 przypadków na 1000 zakażeń)520

Grupy wysokiego ryzyka

Niektóre populacje wykazują zwiększone ryzyko rozwoju reaktywnego zapalenia stawów:316

  • Pacjenci z zakażeniem HIV, szczególnie mężczyźni seropozytywni dla HLA-B27 (ReA rozwija się u prawie 75% HIV-pozytywnych mężczyzn z HLA-B27)3
  • Populacja wojskowa (zwiększone ryzyko narażenia na patogeny wywołujące infekcje przewodu pokarmowego podczas rozmieszczenia)2324
  • Osoby z obniżoną odpornością25
  • Zwiększona częstość występowania ReA obserwowana jest w populacji HIV-dodatniej w Afryce Subsaharyjskiej, gdzie prawie wszystkie przypadki ReA związane z HIV są HLA-B27-negatywne16

Trendy epidemiologiczne i monitoring

Epidemiologia reaktywnego zapalenia stawów ulega zmianom z różnych powodów, w tym:26

  • Różnice w podejściu diagnostycznym i prezentacjach klinicznych26
  • Różne stopnie nasilenia infekcji26
  • Zmiany w mikrobiomie26
  • Poprawa warunków higienicznych w krajach rozwiniętych, co może prowadzić do zmniejszenia częstości występowania ReA27

Niektóre badania sugerują spadek częstości występowania ReA związanego z chlamydią, co może odzwierciedlać efekt wczesnego rozpoznania i strategii leczenia.16 Jednakże francuskie badanie retrospektywne z dwóch ośrodków wykazało, że częstość występowania ReA u pacjentów hospitalizowanych na oddziale reumatologicznym nie zmieniła się między 2002 a 2012 rokiem w porównaniu z okresem 1986-1996.7

Obserwuje się również nowe czynniki wywołujące ReA, takie jak:16

  • Nietypowe organizmy jak Clostridium difficile i Giardia lamblia16
  • Zapalenie stawów krzyżowo-biodrowych po COVID-1916

Wyzwania w monitorowaniu

Dokładne monitorowanie epidemiologii reaktywnego zapalenia stawów napotyka na szereg wyzwań:328

  • Brak jednolitej definicji choroby i kryteriów klasyfikacyjnych3
  • Trudności w różnicowaniu ReA od innych zapaleń stawów3
  • Występowanie bezobjawowych zakażeń chlamydią3
  • Niedodiagnozowanie i niedostateczne raportowanie przypadków3
  • Szeroka zmienność szacunkowej częstości występowania ReA po zakażeniu (1-26%)28

Część badaczy sugeruje, że częstość występowania ReA mogła być niedoszacowana, a choroba może być tak powszechna jak reumatoidalne zapalenie stawów.7 Różnorodność manifestacji klinicznych, różne stopnie aktywności choroby oraz różnice geograficzne i genetyczne utrudniają diagnozę.7

Status socjoekonomiczny a reaktywne zapalenie stawów

Dane epidemiologiczne wskazują na związek między statusem socjoekonomicznym a przebiegiem reaktywnego zapalenia stawów. W populacjach o niższym statusie socjoekonomicznym obserwuje się:123

  • Wyższą aktywność choroby12
  • Gorsze funkcjonowanie układu ruchu123

Przebieg naturalny i rokowanie

Reaktywne zapalenie stawów może mieć różny przebieg kliniczny:1029

  • Samoograniczające się – u większości pacjentów ciężkie objawy utrzymują się przez kilka tygodni do sześciu miesięcy1030
  • Nawracające – 15-50% przypadków doświadcza nawrotów zapalenia stawów10
  • Przewlekłe zapalenie stawów lub zapalenie stawów krzyżowo-biodrowych występuje w 15-30% przypadków1031
  • Postępujące10

Do 63% pacjentów z reaktywnym zapaleniem stawów może rozwinąć przewlekłe zapalenie stawów.29 Jednak ogólne rokowanie dla ReA jest dobre – większość pacjentów jest w dużej mierze wolna od objawów po około 6 miesiącach (z lub bez specyficznej terapii).30 W fińskim badaniu tylko 4-19% pacjentów z ReA wywołanym przez Yersinia, Salmonella, Shigella i Chlamydia miało objawy utrzymujące się ponad 6 miesięcy.30

Zmieniający się profil mikrobiologiczny i kliniczny reaktywnego zapalenia stawów sugeruje, że reumatolodzy powinni ponownie rozważyć podejście do identyfikacji i leczenia tej choroby.32

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  1. 10.04.2026
  2. www.leksykon.com.pl

Materiały źródłowe

  • #1 Reactive Arthritis – StatPearls – NCBI Bookshelf
    https://www.ncbi.nlm.nih.gov/books/NBK499831/
    Reactive arthritis is relatively rare, and the incidence in population-based studies is reported to be 0.6 to 27 per 100,000. It is more common in adult males in the second and third decades of life. About 1% to 3% of patients with nonspecific urethritis develop an arthritis episode. Overall, higher disease activity and worse functional capacity are seen in the lower socioeconomic populations. […] Reactive arthritis is known to be triggered by a bacterial infection, particularly of the genitourinary (Chlamydia trachomatis, Neisseria gonorrhea, Mycoplasma hominis, and Ureaplasma urealyticum) or gastrointestinal (GI) tract (Salmonella enteritidis, Shigella flexneri, and S. disenteriae, Yersinia enterocolitica, Campylobacter jejuni, Clostridium difficile). The incidence is about 2% to 4% after a urogenital infection, mainly with Chlamydia trachomatis, and varies from 0% to 15% after gastrointestinal infections with Salmonella, Shigella, Campylobacter, or Yersinia. This might be affected by the epidemiological and environmental factors, the pathogenicity of the bacteria, and differences in the study designs. The enteric ReA occurs commonly following enteric infections. However, chlamydia associated ReA is endemic, especially in developed countries.
  • #2 Reactive Arthritis – StatPearls – NCBI Bookshelf
    https://www.ncbi.nlm.nih.gov/sites/books/NBK499831/
    Reactive arthritis is relatively rare, and the incidence in population-based studies is reported to be 0.6 to 27 per 100,000. It is more common in adult males in the second and third decades of life. About 1% to 3% of patients with nonspecific urethritis develop an arthritis episode. Overall, higher disease activity and worse functional capacity are seen in the lower socioeconomic populations. […] The incidence is about 2% to 4% after a urogenital infection, mainly with Chlamydia trachomatis, and varies from 0% to 15% after gastrointestinal infections with Salmonella, Shigella, Campylobacter, or Yersinia. This might be affected by the epidemiological and environmental factors, the pathogenicity of the bacteria, and differences in the study designs. The enteric ReA occurs commonly following enteric infections. However, chlamydia associated ReA is endemic, especially in developed countries.
  • #3 Reactive Arthritis: Practice Essentials, Background, Pathophysiology
    https://emedicine.medscape.com/article/331347-overview
    Data on the incidence and prevalence of ReA are scarce, partly because of a lack of a disease definition and classification criteria; these factors complicate differentiation of ReA from other arthritides. The frequency is estimated to be 3.5-5 cases per 100,000 population. The incidence reported in US Navy personnel over a 10-year period was 4 cases per 100,000 men per year. The prevalence of ReA may be relatively high among patients with AIDS, especially men who are seropositive for HLA-B27. ReA develops in almost 75% of HIV-positive men with HLA-B27. […] An estimated 1-3% of all patients with a nonspecific urethritis develop an episode of arthritis. The incidence is 1-4% after enteric infection. This number jumps to 20-25% after bacterial enteritis in HLA-B27-positive individuals. Prevalence of asymptomatic chlamydial infections, underdiagnosis, and underreporting may make the incidence even higher. Worse functional capacity and higher disease activity are observed in the lower socioeconomic classes.
  • #4 Reactive Arthritis
    https://elsevier.health/en-US/preview/reactive-arthritis-co
    ReA is rare, with an estimated 3.5 to 5 per 100,000 patients in the United States. […] Some recent data suggest prevalence is decreasing, perhaps because of better recognition and treatment of causative organisms. […] Ct (Chlamydia trachomatis) is the most common etiologic agent causing ReA in the United States. […] Males are more likely to develop Ct-induced ReA whereas the gender prevalence is approximately equal in the postdysentery form of ReA. […] Adults are more likely to develop ReA than children. […] True attack rate of Ct-induced ReA might be difficult to ascertain because data suggest asymptomatic Ct infections can cause ReA.
  • #5 Reactive arthritis epidemiology and demographics – wikidoc
    https://www.wikidoc.org/index.php/Reactive_arthritis_epidemiology_and_demographics
    The incidence of reactive arthritis following a gastrointestinal or genitourinary infection is approximately 3-27 cases per 100,000 individuals worldwide. The prevalence of reactive arthritis is approximately 30-40 cases per 100,000 individuals worldwide. Reactive arthritis commonly affects young adults in the age group of 18-35 years of age. Men are more commonly affected with reactive arthritis than females with male to female ratio of approximately 4:1. There is no racial predilection to reactive arthritis. […] The incidence rate of reactive arthritis varies with the underlying infection. […] The incidence rate of reactive arthritis following Campylobacter infection is 900 per 100,000 cases. The incidence rate of reactive arthritis following Salmonella and Shigella infection is 1200 per 100,000 cases. […] Patients of all age groups may develop reactive arthritis. […] Reactive arthritis affects both men and women. However, men are more commonly affected than females. The male to female ratio is approximately 4:1. […] There is no racial predilection to reactive arthritis.
  • #6 Reactive Arthritis | Concise Medical Knowledge
    https://www.lecturio.com/concepts/reactive-arthritis/
    Reactive arthritis develops in: 1%3% of patients with urethritis. 1%4% of patients with an enteric infection. Incidence: 0.627 cases per 100,000 worldwide. Prevalence: 3040 per 100,000 adults. More common in men. Occurs more frequently in young adults (40 years of age). 70%90% have the HLA-B27 allele.
  • #7
    https://link.springer.com/article/10.1007/s11926-021-01018-6
    This article presents a comprehensive narrative review of reactive arthritis (ReA) with focus on articles published between 2018 and 2020. […] In view of the increasingly large spectrum of causative agents, diagnostic consideration for the disease must include the entire panel of post-infectious arthritides termed ReA. […] The French two-centre retrospective study reports that the frequency of ReA in patients hospitalized in rheumatology department did not change between 2002 and 2012 compared with between 1986 and 1996. […] The review highlights that epidemiological studies have indicated a diversity of the incidence and frequency of Chlamydia-associated ReA in different parts of the world, with evidence of declining incidence in some regions. […] The review shows a complete list of the arthritogenic agents which are reported to be associated with the development of ReA. The authors believe that the prevalence of ReA has been underestimated because of the multiple clinical manifestations, different degrees of disease activity, and geographical and genetical differences that make the diagnosis many times more difficult, although the disease may be as common as rheumatoid arthritis. […] The overview discusses case reports of acute arthritis or dactylitis associated with SARS-CoV-2 infection, some of which may be suggestive of reactive arthritis. Potential hypothetic mechanisms involved in the pathogenesis of the arthritis are introduced.
  • #8 Reactive Arthritis: Practice Essentials, Background, Pathophysiology
    https://emedicine.medscape.com/article/331347-overview
    A population-based study assessed ReA after culture-confirmed infections with bacterial enteric pathogens in Minnesota and Oregon. The estimated incidence after culture-confirmed Campylobacter, Escherichia coli O157, Salmonella, Shigella, and Yersinia infections in Oregon was 0.6-3.1 cases per 100,000 population. ReA may occur in 1.5% of Shigella enterocolitis cases and 25% of HLA-B27positive Shigella cases. After an outbreak of S enterica serovar Enteritidis, 42% had complete or incomplete ReA. […] The infections that incite ReA may vary with geographic location. For example, Y enterocolitica is more commonly identified in Europe than in North America and thus is responsible for more cases of ReA in countries such as Finland and Norway. The occurrence of ReA appears to be related to the prevalence of HLA-B27 in a population and to the rate of urethritis/cervicitis and infectious diarrhea.
  • #9 Reactive Arthritis: Practice Essentials, Background, Pathophysiology
    https://emedicine.medscape.com/article/331347-overview
    In Norway, an annual incidence of 4.6 cases per 100,000 population for chlamydial ReA and an incidence of 5 cases per 100,000 population for enteric bacteriainduced ReA were reported in 1988-1990. In Finland, nearly 2% of males were found to have ReA after nongonococcal urethritis; the incidence of HLA-B27 is higher in the Finnish population. In the United Kingdom, the incidence of ReA after urethritis is about 0.8%. In the Czech Republic, the annual incidence of ReA in adults during 2002-2003 was reported at 9.3 cases per 100,000 population.
  • #10 Reactive arthritis – Wikipedia
    https://en.wikipedia.org/wiki/Reactive_arthritis
    Reactive arthritis may be self-limiting, frequently recurring, chronic, or progressive. Most patients have severe symptoms lasting a few weeks to six months. 15 to 50 percent of cases involve recurrent bouts of arthritis. Chronic arthritis or sacroiliitis occurs in 15-30 percent of cases. […] Because women may be underdiagnosed, the exact incidence of reactive arthritis is difficult to estimate. A few studies have been completed, though. In Norway between 1988 and 1990, the incidence was 4.6 cases per 100,000 for chlamydia-induced reactive arthritis and 5 cases per 100,000 for that induced by enteric bacteria. In 1978 in Finland, the annual incidence was found to be 43.6 per 100,000.
  • #11 Reactive arthritis | Radiology Reference Article | Radiopaedia.org
    https://radiopaedia.org/articles/reactive-arthritis?embed_domain=hackmd.io%25252525252525252F%252525252525252540yipuafecsl2jsu8smr5njq%25252525252525252Fbnjhjgjghjghjghfavicon.icofavicon.ico&lang=gb
    Reactive arthritis most commonly occurs in males between ages 15-35. It has an incidence of ~1 in 100 following enteric infections. […] Reactive arthritis is a sterile inflammatory monoarticular or oligoarticular arthritis that follows an infection at a different site, commonly enteric or urogenital. It is classified as a type of seronegative spondyloarthropathy.
  • #12
    https://step2.medbullets.com/rheumatology/120724/reactive-arthritis
    Epidemiology […] Demographics […] age […] 20-40 years of age […] sex […] following a genitourinary infection, it is more common to develop reactive arthritis in men […] affects men and women equally a gastrointestinal infection […] Risk factors […] HLA-B27 positivity […] […] […] Most cases spontaneously recover
  • #13 Reactive arthritis: MedlinePlus Medical EncyclopediaLock
    https://medlineplus.gov/ency/article/000440.htm
    Reactive arthritis is a type of arthritis that follows an infection. […] Reactive arthritis most often occurs in men between the ages of 20 and 40, although it does sometimes affect women. […] In up to one half of people thought to have reactive arthritis, there may be no infection. […] The disorder is rare in young children, but it may occur in teenagers. Reactive arthritis may occur in children ages 6 to 14 after Clostridium difficile gastrointestinal infections. […] Reactive arthritis may go away in a few weeks, but it can last for a few months and require medicines during that time. Symptoms may return over a period of years in up to one half of the people who have this condition. […] Epidemiology of clostridium difficile infection-associated reactive arthritis in children: an underdiagnosed, potentially morbid condition. […] Epidemiology: time to revisit the concept of reactive arthritis. […] Prevalence of chlamydia-associated reactive arthritis. […] Reactive and postinfectious arthritis.
  • #14 Reactive Arthritis – UF Health
    https://ufhealth.org/conditions-and-treatments/reactive-arthritis
    Reactive arthritis is a type of arthritis that follows an infection. […] Reactive arthritis most often occurs in men between the ages of 20 and 40, although it does sometimes affect women. […] Reactive arthritis may occur in children ages 6 to 14 after Clostridium difficile gastrointestinal infections. […] Reactive arthritis may go away in a few weeks, but it can last for a few months and require medicines during that time. […] Epidemiology of clostridium difficile infection-associated reactive arthritis in children: an underdiagnosed, potentially morbid condition. […] Epidemiology: time to revisit the concept of reactive arthritis. […] Prevalence of chlamydia-associated reactive arthritis. […] Reactive and postinfectious arthritis.
  • #15 Reactive arthritis – GPnotebook
    https://gpnotebook.com/pages/rheumatology/reactive-arthritis
    reactive arthritis is a systemic disease that affects young people between the second and fourth decades of life. It can affect children and older individuals […] usually occurs 2-4 weeks after a genitourinary (male: female, 9:1) or enteric (male: female, 1:1) infection […] any infectious microorganism can result in reactive arthritis, but those more commonly involved are Chlamydia trachomatis (C. trachomatis), Yersinia, Salmonella, Campylobacter and Streptococcus […] difficult to determine because of the lack of diagnostic criteria, because of the difficulty in identifying, recognizing and treating the causative organisms, which can alter the subsequent course of the disease, the genetic variability of HLA-B27 and the presence of local environmental factors that also play a role, such as Yersinia enterocolitica infection, which is more common in certain geographic areas than in others.
  • #16 Reactive Arthritis: Symptoms and Treatment | Doctor
    https://patient.info/doctor/reactive-arthritis-pro
    Reactive arthritis commonly affects young adults, most frequently white and carrying the HLA-B27 allele. […] SARA is more commonly seen in men, with a ratio of over 10:1, although it may be under-diagnosed in women. […] Reactive arthritis has been increasing in incidence in the sub-Saharan HIV-positive population, where almost all cases of HIV-associated ReA are HLA-B27-negative. Similar observations have not been documented in Caucasian populations with HIV. […] C. trachomatis and Chlamydia pneumoniae are the most frequent causative pathogens. A recent decrease in the incidence of chlamydia-related SARA has been documented, which may reflect a response to early recognition and treatment strategies. […] Up to 16% of cases are associated with Neisseria gonorrhoeae. […] Non-travel-related outbreaks of Shigella-associated reactive arthritis suggest a possible sexually-transmitted route. […] Reactive arthritis may be associated with tuberculosis (Poncet’s disease). […] Arthritis may also occur after infection with atypical organisms such as Clostridium difficile and Giardia lamblia. […] Post-COVID sacroiliitis has been reported.
  • #17 Reactive Arthritis – Musculoskeletal and Connective Tissue Disorders – Merck Manual Professional Edition
    https://www.merckmanuals.com/professional/musculoskeletal-and-connective-tissue-disorders/joint-disorders/reactive-arthritis
    The prevalence of the human leukocyte antigen B27 (HLA-B27) allele in patients with reactive arthritis may be as high as approximately 80% (PMID 34144605), compared with estimates from the general population with estimates of 7% in healthy controls (1, 2), thus supporting a genetic predisposition. […] Compared to patients without HLA-B27 allele, patients with HLA-B27 allele have more severe arthritis, extraarticular manifestations, and more prolonged courses.
  • #18 Reactive Arthritis – Harvard Health
    https://www.health.harvard.edu/pain/reactive-arthritis-a-to-z
    Reactive arthritis is an uncommon disease that causes inflammation of the joints and, in many cases, other areas, particularly the urinary tract and eyes. Reactive arthritis is most common in people between the ages of 20 and 40, with a prevalence of about 0.03% (30 per 100,000). […] Scientists believe that people who develop reactive arthritis have a certain genetic makeup. Supporting the theory that genetic makeup is a risk factor, about 50% of people with reactive arthritis carry a gene called HLA-B27, compared with 8% of the general population. […] Reactive arthritis is thought to be an autoimmune disorder, which means the body’s immune system mistakenly attacks its own tissues. […] A doctor may suspect you have reactive arthritis when the typical symptoms develop after you had an infection. […] The care of people with reactive arthritis should be coordinated by their primary care physician with regular monitoring by appropriate specialists, which may include a dermatologist, ophthalmologist, rheumatologist or urologist.
  • #19 Orphanet: Reactive arthritis
    https://www.orpha.net/en/disease/detail/29207
    A rare spondyloarthritis characterized by acute or chronic sterile synovitis with or without extra-articular manifestations, becoming manifest after an infection. […] Annual incidence for acute reactive arthritis is conservatively estimated between 1/11,000-166,000, although this may be an underestimate. The prevalence of the chronic form is unknown. The disease most commonly affects young adults and is associated with HLA-B27 allele, especially in its chronic form. […] Reactive arthritis is typically triggered by Gram-negative infections (commonly due to Chlamydia, Shigella, Salmonella, or Yersinia) in genetically predisposed individuals. […] Management aims at eradication of the underlying infection (antibiotics) and reduction of joint pain and inflammation (analgesics, anti-inflammatory drugs, steroids and immunosuppressants), as well as rest and specific treatment of extraarticular manifestations.
  • #20 A Case of Reactive Arthritis in a Healthy Adult | Consultant360
    https://www.consultant360.com/photoclinic/case-reactive-arthritis-healthy-adult
    Reactive arthritis was initially described in 1916 by Hans Reiter as Reiter syndrome. It is classically described as a form of seronegative spondyloarthropathy that typically follows a gastrointestinal or urogenital infection. The incidence of reactive arthritis differs depending on the preceding triggering infection. It affects only 1.4% of children following a Clostridioides difficile infection but affects about 4% to 8% of patients after a genital chlamydia infection. Results of a systematic review showed that reactive arthritis had occurred in 12 cases per 1000 Salmonella infections, 9 cases per 1000 Campylobacter infections, and 12 cases per 1000 Shigella infections. The relative risk for developing reactive arthritis is highest among women and adults aged 20 to 40 years. Some studies have found that White individuals are more frequently affected, possibly because of the higher frequency of human leukocyte antigen B27 in this population, as the antigen is prevalent in 50% to 80% of patients with reactive arthritis.
  • #21 Reactive Arthritis (Reiter Syndrome) | 5-Minute Clinical Consult
    https://www.unboundmedicine.com/5minute/view/5-Minute-Clinical-Consult/1688913/0/Reactive_Arthritis__Reiter_Syndrome_
    The epidemiology is similar to other reactive arthritides, typically characterized by sterile joint inflammation associated with infections originating at nonarticular sites. […] Predominant age: 20 to 40 years. […] Predominant sex: male female. […] 0.21% incidence after bacterial dysentery outbreaks. […] Complicates 12% of nongonococcal urethritis cases. […] ~35 cases per 100,000 individuals per year.
  • #22 Reactive Arthritis (Reiter Syndrome) | 5-Minute Clinical Consult
    https://www.unboundmedicine.com/5minute/view/5-Minute-Clinical-Consult/1688913/1/Reactive_Arthritis__Reiter_Syndrome_
    Reiter syndrome is a seronegative, multisystem, inflammatory disorder classically involving joints, the eye, the lower genitourinary (GU) tract, and the skin. […] The epidemiology is similar to other reactive arthritides, typically characterized by sterile joint inflammation associated with infections originating at nonarticular sites. […] Predominant age: 20 to 40 years. […] Predominant sex: male female. […] 0.21% incidence after bacterial dysentery outbreaks. […] Complicates 12% of nongonococcal urethritis cases. […] ~35 cases per 100,000 individuals per year.
  • #23 The epidemiology of infectious gastroenteritis related reactive arthritis in U.S. military personnel: a case-control study | BMC Infectious Diseases | Full Text
    https://bmcinfectdis.biomedcentral.com/articles/10.1186/1471-2334-10-266
    Reactive arthritis (ReA) is a recognized sequela of infectious gastroenteritis (IGE). However, the population-based incidence of IGE-related ReA is poorly defined, and the risk of disease has not previously been characterized in a military population. The intent of this study was to provide estimates of the incidence and morbidity associated with IGE-related ReA in the U.S. military population. […] Overall incidence was 4.1 (95% CI: 3.7, 4.5) and 132.0 (95% CI, 130.0-134.0) per 100,000 for specific ReA and N.A.A, respectively. […] After adjusting for potential confounders, there was a significant association between IGE and ReA (specific reactive arthritis OR: 4.42, 95% CI: 2.24, 8.73; N.A.A OR: 1.76, 95% CI: 1.49, 2.07). […] Reactive arthritis may be more common in military populations than previously described. The burden of ReA and strong association with antecedent IGE warrants continued IGE prevention efforts.
  • #24 The epidemiology of infectious gastroenteritis related reactive arthritis in U.S. military personnel: a case-control study | BMC Infectious Diseases | Full Text
    https://bmcinfectdis.biomedcentral.com/articles/10.1186/1471-2334-10-266
    The US military is at high risk of exposure to IGE-causing pathogens during deployment and may subsequently be at an increased risk of ReA. […] We found an incidence of 4.1 per 100,000 persons for specific ReA in an active duty population. […] Our actual number of documented cases of IGE was very low; however relying on medical records for documentation of IGE severely underestimates the true incidence. […] We found an increased odds of prior IGE in ReA cases compared to matched controls, despite the low rate of documented antecedent gastroenteritis. After controlling for covariates, the OR for specific ReA was 4.42 (95% CI: 2.24, 8.73). […] In summary, we found that ReA was more prevalent than previously recognized in the U.S. active duty military population, especially when non-specific ReA cases were considered. This represents a significant burden on the military healthcare system and may be an important medical condition in returning veterans.
  • #25 Reactive arthritis | Description, Causes, Symptoms, & Treatment | Britannica
    https://www.britannica.com/science/reactive-arthritis
    Reactive arthritis is rare. It occurs most commonly in males between the ages of 20 and 50. […] A genetic factor (HLA-B27) has been identified that predisposes a person to the disorder. […] The condition also tends to affect individuals with weakened immune systems.
  • #26
    https://link.springer.com/article/10.1007/s40588-020-00152-6
    Reactive arthritis is considered to be part of the spectrum of the spondyloarthritis. Its epidemiology is changing worldwide due to several reasons, among them are as follows: different diagnosis approach and clinical presentations, different grades of infection, microbiome changes, etc. […] The understanding of pathophysiological models is challenging, but recent studies contribute to elucidate the major factors involved in the development of the disease. […] The association between the microbiome changes and spondyloarthropathies (ReA) is becoming increasingly evident. […] The incidence of sexually acquired reactive arthritis: a systematic literature review. […] Epidemiology of spondyloarthropathies in Central America.
  • #27 Evolution over thirty years of the profile of inpatients with reactive arthritis in a tertiary rheumatology unit | Reumatología Clínica
    https://reumatologiaclinica.org/en-evolution-over-thirty-years-profile-articulo-S2173574318300030
    Reactive arthritis (ReA) is sterile arthritis occurring after extra articular bacterial infection. The aim of this study was to analyze, over 30 years, clinical, biological and imaging characteristics as well as therapeutic management of new cases of ReA, comparing two periods. […] Reactive arthritis may have two backgrounds: epidemic, with classical description during world war 1st, and sporadic. It corresponds to arthritis related to a preceding infection outside the joint, mainly in the gut or the genito urinary tract, with some classical species, and other less frequent (e.g. Clostridium or N. gonorrhoea). The estimated annual incidence varies among studies and countries between 0.6 and 30/1,000,000. Due to improvement in collective hygienic conditions, one may expect a reduction in incidence of ReA in developed countries.
  • #28 Reactive arthritis incidence in a community cohort following a large waterborne campylobacteriosis outbreak in Havelock North, New Zealand | BMJ Open
    https://bmjopen.bmj.com/content/12/6/e060173
    Epidemiology Original research Reactive arthritis incidence in a community cohort following a large waterborne campylobacteriosis outbreak in Havelock North, New Zealand […] We aimed to determine the incidence of probable reactive arthritis (ReA) cases in individuals with culture-confirmed campylobacteriosis (CC), self-reported probable campylobacteriosis (PC) and those reporting no diarrhoea (ND). […] We describe high probable ReA incidences among gastroenteritis case types during a very large Campylobacter gastroenteritis outbreak using a resource-efficient method that is feasible to employ in future outbreaks. […] Estimates of ReA incidence following campylobacter infection vary widely from 1% to 26%. […] This wide variation is likely due, in part, to lack of a standard definition for ReA and varying methods for estimating ReA incidence.
  • #29 A Case of Reactive Arthritis in a Healthy Adult | Consultant360
    https://www.consultant360.com/photoclinic/case-reactive-arthritis-healthy-adult
    Reactive arthritis is thought to be a self-limiting disease, although up to 63% of patients with reactive arthritis develop chronic arthritis. As such, health care providers need to be clear with their patients regarding the natural history of the disease and treatment expectations. Generally, the same therapies used for management of acute reactive arthritis are used for chronic arthropathies and are primarily based on the use of NSAIDs, although the use of sulfasalazine and biologic therapies are under further study.
  • #30 Reactive Arthritis | MedUni Vienna
    https://innere-med-3.meduniwien.ac.at/en/unsere-abteilungen/rheumatologie/patientinneninformationen/services/services-4/
    ReA usually occurs in younger adults and affects women and men in roughly equal numbers. […] Reactive arthritis: epidemiology, clinical features, and treatment. […] The prognosis for ReA is generally good. Most patients are largely symptom-free after around 6 months (with or without specific therapy, see below). Only 4-19% of patients with ReA caused by Yersinia, Salmonella, Shigella and Chlamydia in a Finnish study had symptoms after more than 6 months.
  • #31 Reiter’s Syndrome
    https://mobile.fpnotebook.com/Rheum/Spondylitis/RtrsSyndrm.htm
    Most common inflammatory Polyarthritis in young men. […] Incidence: as high as 33 in 100,000 males. […] More commonly affects men by ratio of 9:1 to 5:1. […] Age of onset as early as 13 years. […] Chronic Arthritis may develop in up to 30% of cases.
  • #32 Time to revisit the concept of reactive arthritis | Nature Reviews Rheumatology
    https://www.nature.com/articles/nrrheum.2017.69
    The changing microbial and clinical profile of reactive arthritis suggests that rheumatologists need to reconsider the approach to its identification and treatment. […] Reactive arthritis at the Sydney Sexual Health Centre 19922012: declining despite increasing chlamydia diagnoses. […] On the difficulties of establishing a consensus on the definition of and diagnostic investigations for reactive arthritis.