Zespół post-polio
Etiologia i przyczyny
Zespół post-polio (PPS) to przewlekła, postępująca choroba neuromięśniowa rozwijająca się 10-40 lat po pierwotnym zakażeniu wirusem poliomyelitis, dotykająca 25-80% ozdrowieńców. Etiologia PPS pozostaje niejasna, jednak dominująca teoria „zmęczenia neuronalnego” wskazuje na stopniową degenerację neuronów ruchowych w rdzeniu kręgowym, które podczas ostrej fazy polio uległy uszkodzeniu. Kompensacyjny rozrost odgałęzień neuronów prowadzi do zwiększonego stresu metabolicznego i ostatecznej degeneracji. Inne hipotezy obejmują przeciążenie mięśni pozostałych po polio („overexertion phenomenon”), podłoże immunologiczne z aktywnym procesem zapalnym w OUN oraz przyspieszone starzenie się neuronów ruchowych. Czynniki ryzyka rozwoju PPS to m.in. ciężkość pierwotnego zakażenia, wiek zachorowania, płeć żeńska, stopień powrotu do zdrowia, nadmierna aktywność fizyczna oraz objawy oddechowe wymagające wentylacji mechanicznej. Badania cytogenetyczne wskazują na uszkodzenia chromosomów (1p36.1) i polimorfizmy receptora wirusa polio (PVR) jako potencjalne czynniki genetyczne.
Zespół post-polio – Etiologia, przyczynowość, przyczyny
Zespół post-polio (Post-Polio Syndrome, PPS) to grupa potencjalnie upośledzających objawów, które pojawiają się dekady po pierwotnym zachorowaniu na polio (poliomyelitis). Objawy te zazwyczaj rozwijają się 10-40 lat po początkowym zakażeniu wirusem polio, najczęściej po okresie długotrwałej stabilizacji funkcji neurologicznych.12 Jest to schorzenie, które dotyka tylko osoby, które przeszły polio, a według różnych badań rozwija się u około 25-40% osób po przebytym polio, choć nowsze dane sugerują, że nawet u 80% ozdrowieńców mogą wystąpić objawy PPS.34
Teorie dotyczące rozwoju PPS
Mimo wielu lat badań, dokładna etiologia zespołu post-polio pozostaje niejasna. Naukowcy zaproponowali kilka teorii wyjaśniających mechanizm powstawania PPS, jednak żadna z nich nie została jednoznacznie potwierdzona jako jedyna przyczyna.56
Teoria zmęczenia neuronalnego (neural fatigue)
Najbardziej akceptowana teoria, znana jako teoria „zmęczenia neuronalnego”, zakłada, że PPS jest wynikiem stopniowego zwyrodnienia neuronów ruchowych w rdzeniu kręgowym, które zostały uszkodzone podczas pierwotnego zakażenia wirusem polio.7 Podczas ostrej fazy polio wirus uszkadza lub niszczy wiele neuronów ruchowych, szczególnie w rdzeniu kręgowym. Aby skompensować utratę tych neuronów, pozostałe neurony wypuszczają nowe odgałęzienia (sprouting) i zwiększają swoją objętość, tworząc większe jednostki motoryczne.18
Ten proces umożliwia odzyskanie funkcji mięśni, ale jednocześnie powoduje zwiększony stres metaboliczny dla pozostałych komórek nerwowych, które muszą odżywiać dodatkowe włókna. Z biegiem lat, ten długotrwały stres może przewyższyć możliwości neuronów, prowadząc do stopniowego rozpadu nowo utworzonych włókien, a ostatecznie do degeneracji samego neuronu.910
Teoria nadmiernego użycia (muscle overuse)
Inna hipoteza sugeruje, że PPS może wynikać z nadmiernego używania pozostałych mięśni. Osoby po polio często kompensują słabsze mięśnie poprzez nadmierne obciążanie tych silniejszych, co z czasem prowadzi do ich przeciążenia i zwyrodnienia.11 Ten mechanizm przeciążeniowy, określany jako „overexertion phenomenon”, może prowadzić do degeneracji włókien mięśniowych i ich osłabienia.10
Teoria ta zakłada, że wieloletnie zwiększone obciążenie metaboliczne pozostałych neuronów ruchowych prowadzi do drugiej fali neurodegeneracji i niepełnosprawności, co odpowiada pojawieniu się PPS.9
Udział układu immunologicznego
Niektórzy badacze sugerują, że PPS może mieć podłoże immunologiczne. Według tej teorii, pierwotne zakażenie polio może wywołać reakcję autoimmunologiczną, w której układ odpornościowy organizmu atakuje własne komórki nerwowe, traktując je jak substancje obce.511
Badania wykazały obecność aktywnego procesu zapalnego w rdzeniu kręgowym ze zwiększonym poziomem cytokin w płynie mózgowo-rdzeniowym u pacjentów z PPS, co mogłoby potwierdzać tę teorię.12 Długotrwałe skutki odpowiedzi immunologicznej organizmu na pierwotne zakażenie wirusem polio mogą wpływać na komórki nerwowe i mięśnie.11
Teoria normalnego starzenia się
Normalny proces starzenia się również może przyczyniać się do rozwoju PPS. U osób po polio utrata neuronów ruchowych związana z wiekiem może być bardziej odczuwalna ze względu na wcześniejsze uszkodzenia spowodowane wirusem.1314
Osoby po polio mogą tracić pozostałe zdrowe neurony szybciej niż normalnie, co przyspiesza pojawienie się objawów osłabienia mięśni i zmęczenia.5
Czynniki ryzyka rozwoju PPS
Nie jest jasne, dlaczego tylko u niektórych ozdrowieńców po polio rozwija się zespół post-polio. Badacze zidentyfikowali jednak kilka potencjalnych czynników ryzyka:715
- Stopień ciężkości pierwotnego zakażenia polio – osoby, które przeszły polio o cięższym przebiegu, z większym uszkodzeniem neuronów ruchowych, wydają się być bardziej narażone na rozwój PPS162
- Wiek zachorowania na polio – zachorowanie w okresie dojrzewania lub w wieku dorosłym może zwiększać ryzyko PPS16
- Płeć żeńska – kobiety mogą być bardziej narażone na rozwój PPS12
- Stopień powrotu do zdrowia po polio – paradoksalnie, silniejszy powrót do zdrowia po polio może zwiększać ryzyko PPS, ponieważ proces zdrowienia mógł nadmiernie obciążyć neurony ruchowe17
- Nadmierna aktywność fizyczna – długotrwałe przeciążenie osłabionych mięśni może przyspieszyć rozwój PPS12
- Objawy oddechowe podczas pierwotnego zakażenia – konieczność stosowania wentylacji mechanicznej w fazie ostrej może zwiększać ryzyko PPS12
Rola czynników genetycznych
Istnieje kilka badań sugerujących genetyczne podłoże rozwoju PPS. Badania cytogenetyczne wykazały znaczące uszkodzenia chromosomów u pacjentów z PPS, głównie w chromosomie 1p36.1.18 Polimorfizm receptora wirusa polio (PVR) jest zgłaszany u pacjentów z polio i jest uważany za czynnik ryzyka rozwoju ostrego poliomyelitis. Polimorfizm PVR może być również potencjalnym czynnikiem ryzyka rozwoju PPS, chociaż nie zostało to jeszcze jednoznacznie potwierdzone.18
Co nie powoduje PPS?
Warto podkreślić, że zespół post-polio nie jest spowodowany ponownym zakażeniem wirusem polio ani reaktywacją uśpionego wirusa. Początkowa teoria sugerująca, że PPS jest spowodowany reaktywacją latentnego wirusa polio w organizmie (podobnie jak półpasiec jest reaktywacją wirusa ospy wietrznej) została zdyskredytowana przez badania laboratoryjne, które nie wykazały obecności aktywnego wirusa polio w organizmie.1920
Zespół post-polio nie jest również chorobą zakaźną – osoby z PPS nie są źródłem zakażenia dla innych.721
Progresja choroby
PPS jest uznawany za powoli postępującą chorobę neuromięśniową.22 Objawy zespołu post-polio rozwijają się powoli, z okresami stabilizacji trwającymi od 3 do 10 lat.23 Choroba może postępować w różnym tempie u różnych pacjentów, a niektórzy mogą doświadczać okresów względnej stabilności na przemian z okresami pogorszenia z postępującym osłabieniem.246
Zdaniem niektórych badaczy, wszyscy ozdrowieńcy po polio ostatecznie rozwiną jakieś objawy PPS, jeśli będą żyć wystarczająco długo.25 Choroba rzadko zagraża życiu, ale objawy mogą znacząco zakłócać zdolność osoby do niezależnego funkcjonowania.26
Wieloczynnikowe podłoże PPS
Coraz więcej dowodów wskazuje, że przyczyny objawów PPS mogą być wieloczynnikowe. Niepełnosprawność wynikająca z ostrego polio, w połączeniu z codziennymi czynnościami, może powodować duże obciążenia działające na nieprawidłowe mięśnie i stawy. Może to prowadzić do problemów, które przyczyniają się do rozwoju PPS, takich jak:23
- Deformacje stawów – skolioza lub sztywność ściany klatki piersiowej2323
- Problemy oddechowe – wynikające z osłabienia mięśni oddechowych, upośledzenia opuszki (bulbar impairment) wpływającego na kontrolę górnych dróg oddechowych lub cyklu oddechowego23
- Inne patologie – np. przewlekła obturacyjna choroba płuc (POChP), astma, otyłość23
- Aspiracja – jeśli występują zaburzenia połykania23
Wpływ uszkodzeń na ośrodkowy układ nerwowy
Inna teoria sugeruje, że pierwotne zakażenie wirusem polio może uszkodzić części niższego mózgu, prawdopodobnie w tym wzgórza i podwzgórza.27 Uszkodzenie siatkowatego układu aktywującego (reticular activating system) i powiązanych obszarów, takich jak wzgórze, może również powodować większość objawów zmęczenia, „mgły mózgowej” i dysautonomii w PPS.19
Badania dr Bruno z Post-Polio Institute wykazały, że produkcja chemikaliów w mózgu jest również zakłócana przez wirusa polio, co prowadzi do problemów poznawczych, szczególnie w warunkach stresu.14
Podobieństwo do chorób neuronu ruchowego
Warto zauważyć, że PPS różni się od sporadycznych lub pierwotnych chorób neuronu ruchowego (MND) ze względu na swoją naturalną historię, która odpowiada temu, co jest uważane za kliniczne nasilenie dziecięcego zakażenia wirusem polio w ośrodkowym układzie nerwowym.28 Jednak niektórzy badacze rozważają, czy PPS jest rzeczywiście formą MND, w tym stwardnienia zanikowego bocznego (ALS) lub postępującego zaniku mięśni (PMA). Tę koncepcję wspierają nakładające się objawy w PPS i ALS lub PMA.9
Wyjątkowo wysoki wskaźnik PPS wśród osób, które przeżyły ostre poliomyelitis, wskazuje na to, że czynniki związane z początkowym zakażeniem lub mechanizmami powrotu do zdrowia są kluczowymi mediatorami patogenezy neurodegeneracji związanej z PPS.9
Podsumowanie aktualnej wiedzy
Mimo wielu badań, dokładny mechanizm powstawania zespołu post-polio pozostaje niejasny. Najbardziej prawdopodobne wyjaśnienie obejmuje kombinację czynników związanych z pierwotnym uszkodzeniem neuronów ruchowych przez wirusa polio, procesami kompensacyjnymi, które nastąpiły podczas powrotu do zdrowia, oraz długoterminowymi skutkami przeciążenia pozostałych neuronów ruchowych.729
Trwają badania nad przyczynami PPS, w tym nad potencjalnymi powiązaniami immunologicznymi. Może to prowadzić do wcześniejszego wykrywania PPS i możliwych metod leczenia w przyszłości.30 Obecnie nie ma leków, które mogłyby zapobiec lub opóźnić osłabienie mięśni, ale objawy można łagodzić za pomocą różnych strategii zarządzania.21
Jedynym sposobem zapobiegania PPS jest zapobieganie polio poprzez szczepienia, co podkreśla znaczenie globalnych programów szczepień przeciwko polio.29 Dla osób, które już przeszły polio, nie ma znanego sposobu na zapobieganie rozwojowi PPS, a naukowcy nadal nie są pewni, dlaczego niektórzy ozdrowieńcy po polio rozwijają PPS, a inni nie.29
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Materiały źródłowe
- #1 Post-polio syndrome | UM Health-Sparrowhttps://www.uofmhealthsparrow.org/departments-conditions/conditions/post-polio-syndrome
Post-polio syndrome is a group of potentially disabling signs and symptoms that appear decades after the initial polio illness. […] There are several theories as to what causes post-polio syndrome, but no one knows for sure. […] A polio infection often damages or destroys many of these motor neurons. Because there are fewer motor neurons, the remaining neurons sprout new fibers and grow bigger. […] This promotes recovery of the use of your muscles, but it also may stress the nerve cell body to nourish the additional fibers. Over the years, this stress may be too much. This may cause the gradual breakdown of the sprouted fibers and, eventually, of the neuron itself.
- #2 Post-Polio Syndrome: What It Is, Symptoms & Treatmenthttps://my.clevelandclinic.org/health/diseases/24584-post-polio-syndrome
Post-polio syndrome (PPS) is a condition that can affect people several years after an initial polio infection. It causes gradual muscle weakness and atrophy. Theres no cure, so treatment focuses on managing symptoms. […] Post-polio syndrome (PPS) is a condition that causes gradual muscle weakness and muscle atrophy (loss) that can affect people whove had polio. PPS usually happens 10 to 40 years after youve recovered from the initial polio infection. […] Post-polio syndrome affects people whove had polio. PPS develops 10 years or more after the original illness and can occur as late as 40 years afterward. […] Approximately 30% to 40% of people whove had polio will develop PPS. A person who was more severely affected by polio may develop a more severe case of PPS. […] Post-polio syndrome is rare because polio is rare. The polio vaccine has gotten rid of polio from the U.S. However, polio still exists in some countries, and cases of PPS still occur.
- #3 POST POLIO SYNDROME – WILDROSE POLIO SUPPORT SOCIETYhttps://polioalberta.ca/home/post-polio-syndrome/
Post-polio syndrome (PPS, or post-poliomyelitis syndrome or post-polio sequelae) is a condition that affects approximately 25 to 40 percent of people who have previously survived an acute attack of poliomyelitis, though more recent studies have shown that 80+% of polio survivors show symptoms of Post Polio Sequelae. […] The precise mechanism that causes PPS is unknown. […] Numerous theories have been proposed to explain post-polio syndrome. Despite this, there are currently no absolutely defined causes of PPS. […] The most widely accepted theory of the mechanism behind the disorder is neural fatigue. […] Another theory is that people who have recovered from polio lose remaining healthy neurons at a faster rate than normal. […] Finally, it has been proposed that the initial polio infection causes an autoimmune reaction, in which the body’s immune system attacks normal cells as if they were foreign substances.
- #4 Post-poliomyelitis syndrome – PubMedhttps://pubmed.ncbi.nlm.nih.gov/15599928/
Post-poliomyelitis syndrome (PPS) is a common neurological disorder that occurs in a large proportion of individuals who have recovered from paralytic poliomyelitis. […] The cause of PPS remains unclear, but is likely due to a distal degeneration of enlarged post-poliomyelitis motor units. […] Contributing factors to PPS may be aging (with motor neuron loss), overuse, and disuse.
- #5 Post-polio syndrome – Wikipediahttps://en.wikipedia.org/wiki/Post-polio_syndrome
Post-polio syndrome (PPS) is a group of latent symptoms of poliomyelitis (polio), occurring in more than 80% of polio infections. The precise mechanism that causes PPS is unknown. Numerous theories have been proposed to explain post-polio syndrome. Despite this, no absolutely defined causes of PPS are known. The most widely accepted theory of the mechanism behind the disorder is „neural fatigue”. The neural fatigue theory proposes that the enlargement of the motor neuron fibers places added metabolic stress on the nerve cell body to nourish the additional fibers. Another theory is that people who have recovered from polio lose remaining healthy neurons at a faster rate than normal. Finally, the initial polio infection is thought to cause an autoimmune reaction, in which the body’s immune system attacks normal cells as if they were foreign substances.
- #6 What Causes Post-Polio Syndrome?https://www.webmd.com/children/what-is-post-polio-syndrome
Post-polio syndrome only affects polio survivors, but its not clear why it happens. […] There are some theories about post-polio syndrome causes, but the exact cause is unknown. […] Its thought that these recovered nerves and fibers get overworked with the stress of years of movement, and they break down over time. It might also happen because your immune system attacks your own tissues, but researchers arent exactly sure. […] Eventually, you lose muscle strength and can have periods of stability mixed with periods of worsening weakness.
- #7https://www.nhs.uk/conditions/post-polio-syndrome/
Post-polio syndrome (PPS) is a poorly understood condition that can affect people who have had polio in the past. […] Post-polio syndrome is where some of these symptoms develop or get worse many years or decades after the original polio infection. […] The exact cause of post-polio syndrome is unclear. It’s not known whether anything can be done to prevent it. […] The leading theory is that it’s the result of the gradual deterioration of nerve cells in the spinal cord (motor neurones) that were damaged by the polio virus. This would explain why the condition can take years to appear. […] Post-polio syndrome isn’t contagious. The theory that the polio virus may lie dormant in your body, causing post-polio syndrome when it becomes reactivated at a later stage, has not been proven. […] It’s not clear why only some people who have had polio develop post-polio syndrome. However, those who had severe polio when they were younger may be more likely to develop the condition.
- #8 Post-polio syndromehttps://www.mymlc.com/health-information/diseases-and-conditions/p/post-polio-syndrome/
Post-polio syndrome refers to a cluster of potentially disabling signs and symptoms that appear decades â an average of 30 to 40 years â after the initial polio illness. […] There are several theories as to what causes post-polio syndrome, but no one knows for sure. […] When poliovirus infects your body, it affects nerve cells called motor neurons â particularly those in your spinal cord â that carry messages (electrical impulses) between your brain and your muscles. […] A polio infection often damages or destroys many of these motor neurons. To compensate for the resulting neuron shortage, the remaining neurons sprout new fibers, and the surviving motor units enlarge. […] Over the years, this stress may be more than the neuron can handle, leading to the gradual deterioration of the sprouted fibers and, eventually, of the neuron itself.
- #9 Post-Polio Syndrome Revisitedhttps://pmc.ncbi.nlm.nih.gov/articles/PMC10123742/
The extraordinarily high rate of PPS among survivors of acute poliomyelitis speaks volumes for factors related to the initial infection or mechanisms of recovery as key pathogenic mediators of PPS-associated neurodegeneration. […] However, re-innervation sprouting leads to the enlargement of motor units, adding metabolic stress to remaining motor neurons. Chronically increased metabolic stress could eventually trigger a second wave of neurodegeneration and disability, corresponding with the emergence of PPS. […] A final consideration is whether PPS is actually a form of MND, including ALS or progressive muscular atrophy (PMA). This notion is supported by the overlapping symptoms in PPS and ALS or PMA.
- #10 What is Post-Polio Syndrome? – Post Poliohttps://post-polio.org/education/what-is-post-polio-syndrome/
Post-Polio syndrome is a condition that affects the survivors of polio decades after the acute illness of poliomyelitis. […] What causes post-polio syndrome? In the early years, there was some speculation that the cause might be a „recurrence” of polio or reactivation of the poliovirus, which is not the case. The generally accepted theory is best demonstrated by the following diagrams. […] Wiechers and Hubbell proposed that these new sprouts are not indefinitely stable…but rather degenerate over time due to an „overexertion” phenomenon resulting once again in muscle fibers that no longer contract, which a survivor recognizes as new weakness and loss of function.
- #11 Understanding Post-Polio Syndrome: Symptoms, Causes, and Treatment | TheHealthSite.comhttps://www.thehealthsite.com/diseases-conditions/understanding-post-polio-syndrome-symptoms-causes-and-treatment-1008474/
Post-Polio Syndrome (PPS) is a less well-known but no less sneaky foe lurking in the shadows. […] Researchers are still looking into the root causes of PPS in the hopes of making more advancements in knowledge and care. […] According to one idea, the initial poliovirus infection may be the reason why certain motor neurons in the spinal cord pass away. Muscle weakness and exhaustion develop as a result of the overworked motor neurons that are still alive. […] Another idea claims that people with polio overuse their remaining muscles to make up for their weaker muscles. The symptoms of PPS may emerge as a result of this ongoing misuse. […] Some researchers think that PPS may be influenced by the immunological system. The long-term effects of the body’s immune reaction to the initial poliovirus infection may still have an impact on nerve cells and muscles.
- #12https://journals.lww.com/ijab/fulltext/2019/09030/postpolio_syndrome__a_review_of_lived_experiences.2.aspx
Postpolio syndrome (PPS) refers to a group of conditions that are present in patients, years after recovery from initial acute paralytic poliomyelitis. About 15%80% of 20 million polio survivors worldwide will experience exacerbation of symptoms which typically appear 1530 years after the resolution of initial poliomyelitis. […] The exact cause of the development of PPS is unknown. However, studies have shown that active inflammatory process is present in the spinal cord with increased level of cytokines in the cerebrospinal fluid. […] Various studies have shown that the risk factors that contribute to PPS include female gender, the presence of a permanent disability and severe residual weakness experienced after polio, normal aging, muscle overuse and disuse, and immune reaction. […] The female gender and respiratory symptoms are the most important risk factors for developing PPS.
- #13 Post-Polio Syndrome – Harvard Healthhttps://www.health.harvard.edu/a_to_z/post-polio-syndrome-a-to-z
Post-polio syndrome is an illness defined by a collection of symptoms that generally occur at least 10-20 years after infection with the polio virus. […] It’s not clear how many polio survivors will be affected by post-polio syndrome. It’s also not clear why some polio survivors develop post-polio syndrome while others do not. […] One theory is overuse of the nerves and muscles that remained working after the initial infection. […] Normal aging likely also contributes to new weakness. […] One theory for post-polio syndrome is that some of the poliovirus remains alive in the brain and spinal cord. This theory is controversial.
- #14 Syndrome – Scottish Post Polio Networkhttps://sppn.org.uk/syndrome/
Post-Polio Syndrome (PPS) refers to a range of symptoms experienced by the polio survivor. […] Research shows that several causes favour the development of PPS. […] The virus damaged more motor neurons than was realised at the time of the infection. For those who experienced paralysis, 90% of nerve cells in the spinal cord were damaged by the virus and half of those died. These damaged neurons sent out new sprouts to turn on muscle fibres enabling many polio survivors to walk again. However, these surviving neurons become less able to deal with the demands placed on them and so are less able to manufacture acetylcholine. […] Furthermore, Dr. Bruno of the Post-Polio Institute, Englewood Hospital and Medical Centre (New Jersey), has shown that the production of chemicals in the brain is also disrupted by the polio virus giving rise to cognitive problems particularly under stress. […] Other causes such as the effects of low blood sugar, medical treatment and ageing on weakened neurons all play a part in the development of PPS.
- #15 Post-Polio Syndrome | Living With Paralysis | Reeve Foundationhttps://www.christopherreeve.org/todays-care/living-with-paralysis/health/causes-of-paralysis/post-polio-syndrome-poliomyelitis/
Over time, some individuals with a history of polio which affected the motor nerves may develop new muscle pain, weakness, or paralysis 10 to 40 years after the original polio episode. This is post-polio syndrome (PPS). […] Post-polio syndrome is not contagious. It is not a re-activation of the virus but rather an effect of deterioration of the replacement or supplemental nerves. […] Post-polio syndrome develops in individuals who have survived polio that impacted motor nerves. There is no vaccine or other medication that can prevent post-polio syndrome nor is there a way to predict who will develop it. […] It appears that individuals who had severe cases of motor nerves affected by polio may be more likely to develop post-polio syndrome.
- #16 Post-polio syndrome | NHS informhttps://www.nhsinform.scot/illnesses-and-conditions/brain-nerves-and-spinal-cord/post-polio-syndrome/
Post-polio syndrome is caused by the polio virus. It only affects people whove had polio although it can take 15 40 years after the infection for it to develop. Its not known if theres anything that can be done to prevent it. […] The exact cause behind wholl experience post-polio syndrome after having the polio virus is unclear. […] It could be because of gradual degeneration (breaking down) of nerve cells (motor neurones) in the brainstem or spinal cord that were damaged by the polio virus. This gradual change explains why it can take years for post-polio syndrome symptoms to appear. […] Over time, these new nerve ends put the motor neurone cell under stress. The cells slowly break down, resulting in the loss of muscle strength. […] People who have had severe polio at a young age or during adolescence (teenage years) might be more likely to experience post-polio syndrome. People who had a more serious infection in early adulthood are also more likely to develop post-polio syndrome.
- #17https://www.byramhealthcare.com/blogs/spinal-cord-disorders-everything-you-need-to-know-about-post-polio-syndrome
While the cause is unclear, there are certain factors that may increase your risk of developing post-polio syndrome. One of the biggest risk factors is the severity of your polio. Severe infections are correlated with higher rates of PPS. Polio infections that occur during adulthood, as opposed to childhood, seem to increase your risk alongside excessive physical activity. Finally, individuals who had a stronger recovery after polio seem to be at a higher risk, as the process of overcoming the virus may put excessive strain on your motor neurons and lead to burn-out. […] The biggest indication of PPS is previous polio infections, as individuals who have not had polio cannot develop post-polio syndrome.
- #18https://journals.lww.com/ijab/fulltext/2019/09030/postpolio_syndrome__a_review_of_lived_experiences.2.aspx
There are only a few studies that establish the genetic basis of developing PPS. A cytogenetic study reported the findings of significant breaks in chromosomes in patients with PPS, predominantly in chromosome 1p36.1. […] Polymorphism of the poliovirus receptor (PVR) is reported in patients with polio and is regarded as a risk factor for developing acute poliomyelitis. PVR polymorphism is a possible risk factor for developing PPS. However, it is not yet confirmed to be present in patients with PPS.
- #19 Post-polio_syndromehttps://www.bionity.com/en/encyclopedia/Post-polio_syndrome.html
Damage to the reticular activating system and related areas such as the thalamus can also produce most of the fatigue, „brain fog”, and dysautonomia symptoms of post-polio, and may be able to cause hormonal changes that result in progressive muscle weakness. […] An early theory stated that PPS is caused by reactivation of latent polio virus in the body, similar to the way that shingles is a reactivation of the chicken pox virus. This theory has been discredited by laboratory studies that show no active polio virus in the body.
- #20 Post-Polio Syndrome (PPS) – DoveMedhttps://www.dovemed.com/post-polio-syndrome-pps
Some individuals are disabled by a set of signs and symptoms that onset many decades (10-40 years) after they have been affected by Polio. This is known as Post-Polio Syndrome (PPS) […] PPS, unlike Polio, is not caused by a virus. On the other hand, it is thought to occur as a result of slow, but progressive degeneration of nerve nodes and the brain, that followed an initial incidence of Polio […] The exact cause of Post-Polio Syndrome, and why it develops after so many years or decades, is unknown […] It is researched that during Polio, the nervous system and brain undergoes some amount of irreversible injury, by the poliovirus […] As the body tries to cope with the (mildly or severely) damaged nervous system, it places additional stress on certain nerve cells (neurons). It is thought that a prolonged overburdening of the neurons, causes them to gradually deteriorate and lead to PPS manifestation […] The poliovirus has no role to play in Post-Polio Syndrome, it is understood to be a purely neuromuscular phenomenon.
- #21 Definitions – Post Poliohttps://post-polio.org/living_with_polio/definitions/
Post-polio syndrome is usually considered a specific new condition. A diagnosis of exclusion is used to determine if a patient has PPS. […] The generally accepted theory is best demonstrated by the following diagrams. […] Wiechers and Hubbell proposed that these new sprouts are not indefinitely stable⦠but rather degenerate over time due to an âoverexertionâ phenomenon resulting once again in muscle fibers that no longer contract, which a survivor recognizes as new weakness and loss of function. […] The new problems facing your loved one are not caused primarily by the poliovirus, but are problems secondary to having polio. Polio survivors experiencing new symptoms have not been re-infected nor are they contagious. […] Although research has not yet identified a medication that stops or delays the weakening of muscles, the symptoms can be managed.
- #22 Poliomyelitis/Post-Polio Syndrome | PM&R KnowledgeNowhttps://now.aapmr.org/poliomyelitis-post-polio-syndrome/
The polio virus is an RNA enterovirus that was historically reported to invade the CNS in about 5% of clinical infections, causing varying degrees of paralysis in about 2% of patients. […] The neurological deterioration and functional decline of post-polio syndrome may be related to normal aging, accelerated degeneration of nerves and joints, overuse myopathy and disuse. […] The most widely accepted hypothesis as to the cause of new weakness, muscle fatigue and pain was proposed by Weichers and Hubbell. […] Post-polio syndrome is considered a slowly progressive neuromuscular disease.
- #23 Post-polio Syndrome: Symptoms and Treatment | Doctorhttps://patient.info/doctor/post-polio-syndrome
Skeletal deformity – scoliosis or chest wall stiffness. […] Other pathology – eg, chronic obstructive pulmonary disease (COPD), asthma, obesity. […] Aspiration – if swallowing is affected. […] The symptoms of post-polio syndrome are slowly progressive, with periods of stability lasting 3-10 years.
- #23 Post-polio Syndrome: Symptoms and Treatment | Doctorhttps://patient.info/doctor/post-polio-syndrome
Post-polio syndrome (PPS) is the onset of new deterioration in function that may occur many years after partial or complete recovery from acute poliomyelitis. […] The exact cause of PPS is unknown: There may be new muscle atrophy and weakness relating to changes in motor neurons. […] Overuse or disuse of muscles plays an important role. […] The cause of PPS symptoms may be multifactorial. For example, disabilities resulting from acute polio, combined with activities of daily living, can produce large stresses acting on abnormal muscles and joints. This may lead to other problems which contribute to PPS, such as: Joint deformities. […] Respiratory problems in PPS may be due to one or more of: Respiratory muscle weakness. […] Bulbar impairment – this may affect control of the upper airway or the respiratory cycle.
- #24 Is Post-Polio Syndrome Progressive? — Polio Networkhttps://polionetwork.org/archive/jk5qac50vkcuxalk22thno52thkp7h
Many polio survivors hear from health care professionals (and others) that Post-Polio Syndrome is not progressive, that it reaches a point and does not progress any further. […] The correct answer/response is that PPS is generally a slowly progressive disease process. […] The cause of PPS is unknown. The new weakness of PPS appears to be related to the degeneration of individual nerve terminals in the motor units. […] Years of high use of these recovered but overly extended motor units add stress to the motor neurons, which over time results in the slow deterioration of the neurons and leads to loss of muscle strength. […] This may be why PPS occurs after a delay and has periods of relative stability combined with periods of decline with progressive weakness.
- #25https://journals.lww.com/nursing/fulltext/2006/12000/managing_postpolio_syndrome_pain.13.aspx
POLIO IS A DISTANT MEMORY for most health care providers, but post-polio syndrome (PPS) is becoming increasingly common in patients who survived the last polio epidemics in the 1950s and 1960s. […] The cause of PPS isn’t known, but researchers have several theories. One is that the ongoing process of denervation and reinnervation of motor neurons gets out of balance, with denervation exceeding reinnervation. A second theory is that persistent latent poliovirus becomes reactivated. A third theory is that a different virus infects the motor neurons, causing weakness. Or, PPS may reflect a normal loss of strength due to aging and weight gain that’s simply more noticeable in patients who’ve had polio. […] Some researchers believe that all polio survivors eventually will develop some symptoms of PPS.
- #26 Post-Polio Syndromehttps://johnshopkinshealthcare.staywellsolutionsonline.com/Library/Encyclopedia/134,569
The symptoms include progressive muscle weakness, pain in the muscles and joints, and tiredness. […] Some people with PPS may eventually need a machine to help with breathing. […] Prescribed special exercise programs, assistive devices, physical therapy, occupational therapy, and medicines may all help you manage the symptoms of PPS. […] PPS is rarely life-threatening, but the symptoms can significantly interfere with a person’s ability to function independently.
- #27 Post-polio syndrome pathophysiology – wikidochttps://www.wikidoc.org/index.php/Post-polio_syndrome_pathophysiology
The precise mechanism that causes post-polio syndrome is unknown. […] Several theories have been proposed to explain post-polio symptoms. One theory of the mechanism behind the disorder is that it is due to „neural fatigue” from overworked neurons. […] Another theory holds that the original viral infection damages portions of the lower brain, possibly including the thalamus and hypothalamus. […] One significant argument in favor of the mitochondrial disruption theory is that it explains the fatigue and cognitive difficulties („brain fog”) symptoms that usually accompany post-polio better than the neural fatigue theory does. […] Damage to the reticular activating system and related areas such as the thalamus can also produce most of the fatigue, „brain fog”, and dysautonomia symptoms of post-polio, and may be able to cause hormonal changes that result in progressive muscle weakness. […] An early theory stated that PPS is caused by reactivation of latent polio virus in the body, similar to the way that shingles is a reactivation of the chicken pox virus. This theory has been discredited by laboratory studies that show no active polio virus in the body.
- #28 Post-Polio Syndrome Revisitedhttps://pmc.ncbi.nlm.nih.gov/articles/PMC10123742/
Post-polio syndrome (PPS) is characterized by recrudescence or worsening of motor neuron disease symptoms decades after recovery from acute paralytic poliovirus infection, i.e., poliomyelitis. […] PPS uniquely differs from sporadic or primary MND due to its natural history corresponding to what is regarded as a clinical recrudescence of a childhood poliovirus CNS infection. […] The mechanism of PPS is not well understood. Potential etiologies include: (1) re-awakening of underlying pathologies that had been masked by repair and recovery but rendered weakened due to aging-associated neuronal and fiber attrition; and (2) prior poliomyelitis causes epigenetic changes that increase vulnerability to sporadic MND. […] Although it is widely accepted that PPS is causally linked to an earlier bout of poliomyelitis, the mechanism driving the recrudescence of motor neuron disease symptoms and neurodegeneration remains unknown.
- #29 Post-Polio Syndrome: What It Is, Symptoms & Treatmenthttps://my.clevelandclinic.org/health/diseases/24584-post-polio-syndrome
Scientists dont yet know the cause of post-polio syndrome. One theory is that it could be due to the recovery from the initial polio infection. During recovery from polio, nerve cells (neurons) in the affected muscles may regrow many smaller branches (dendrites) from the large branches (axons) of nerve cells. These dendrites take over the function of neurons that the polio virus killed. […] Scientists think that, after years of functioning beyond their capacity, the nerve cells weaken and lose their ability to maintain the dendrites. The dendrites then shrink, and the whole muscle becomes weaker. […] At this time, theres no cure for post-polio syndrome. […] The only way to prevent PPS is to prevent getting polio. The only way to do this is to get the polio vaccine. […] If youve had polio, theres nothing you can do to prevent developing post-polio syndrome. Scientists arent sure why some polio survivors develop PPS and others dont.
- #30 Post-Polio Syndrome: Symptoms, Treatment, and Outlookhttps://www.healthline.com/health/post-polio-syndrome
Poliomyelitis (polio) is a severe and potentially life threatening condition caused by the poliovirus. If you had a polio infection as a child and have since recovered, its still possible to develop a complication called post-polio syndrome (PPS). […] The exact cause of PPS is unknown. Experts think PPS may develop as a result of stress on motor neurons from a previous polio infection. While you might recover from the initial infection, you may still experience a gradual deterioration of these neurons. […] Currently, theres no known treatment for PPS. Damage to the affected neurons is irreversible. […] While the exact cause of PPS is unknown, research is ongoing to discover concrete risk factors, including possible immunological links. This could mean earlier detection of PPS and possible treatments in the future.