Overwhelming post-splenectomy infection
Overwhelming post-splenectomy infection | |
---|---|
Other names | Overwhelming post-splenectomy sepsis (OPSS) hematological reasons, being under the age of 2[2] |
Prognosis | Almost invariably fatal without treatment[2] |
An overwhelming post-splenectomy infection (OPSI) is a rare but rapidly fatal infection occurring in individuals following removal (or permanent dysfunction) of the spleen. The infections are typically characterized by either meningitis or sepsis, and are caused by encapsulated organisms including Streptococcus pneumoniae.[3] It is a medical emergency and requires immediate treatment. Death has been reported to occur within 12 hours.[4]
The spleen is necessary for protection against encapsulated bacteria (see Mechanism) and as such when removed by splenectomy it can lead to rapid unchallenged infection by encapsulated bacteria. The rapid progression from mild viral symptoms to sepsis is one of the things that makes OPSI particularly dangerous.
Another source of infection[5] are species of Babesia, which are tick-borne parasites that cause babesiosis.[6]
Signs and symptoms
OPSI may initially present with mild viral symptoms such as fever or coughing, however later in infection symptoms may include shakes, shivers, chills, diarrhea, vomiting, malaise, myalgia, headache and abdominal pain.[2][4]
The disease progresses rapidly from the above mentioned symptoms to coma to refractory septic shock and finally death in as little as 24 hours.[4]
Mechanism
The
When the spleen is no longer present (asplenia), IgG and C3b are still bound to bacteria, but they cannot be removed from the blood circulation due to the loss of the splenic macrophages. Hence the bacteria are free to cause infection.
Patients without a spleen often need
Prevention
Measures to prevent OPSI include vaccination, prophylactic antibiotics and patient education.[7][8][9]
Patient education
Knowledge of the risks of asplenia correlates with a greatly reduced risk of OPSI, thus patient education is vital to preventing OPSI and may be the most important factor for preventing OPSI.[10] More and more people are increasingly getting their healthcare information from the internet and the lack of reliable, readable and comprehensive information on the risks of asplenia and splenectomy poses a preventable risk factor for asplenic individuals.[10] The majority (as many as 84%) of asplenic individuals are unaware of the risks of asplenia.[4] Encouraging the wearing of bracelets with information about the condition, the carrying of antibiotics, seeking medical advice before travel, especially to places where malaria and babesia is endemic and seeking immediate medical attention following a bite from an animal has been shown to reduce OPSI risk.[4][2]
Vaccination
The Centers for Disease Control and Prevention's annual vaccine recommendations includes specifics for individuals without a functioning spleen.[11]
The The Green Book (immunisation guidance, UK) in chapter 7[12] covers immunisation of people with underlying medical conditions that affect immunity which includes asplenic patients.
As there are a range of different pneumococcal vaccines, the patient should be offered the most up to date ones (typically 23 valent polysaccharide vaccine and 13 valent conjugate vaccine), if they have not had them already as part of standard schedule. Repeat doses are recommended in patients without a spleen.
The CDC recommends against live vaccines and has specific advice for travellers, which includes malaria avoidance for asplenic individuals.[13]
Prognosis
OPSI is almost always fatal without treatment, but modern treatment has decreased the mortality to approximately 40–70 percent.[2][3][14] Individuals with OPSI are most commonly treated with antibiotics and supportive care.[7]
Epidemiology
The risk of OPSI is 0.23–0.42 percent per year, with a lifetime risk of 5 percent.[7] Most infections occur in the first few years following splenectomy, but the risk of OPSI is lifelong.[3][15]
The risk is greatest for children and elderly (70+ years old), but it can happen at any age. Greater risk is associated with
References
- ^ surgical recall, seventh edition, Lorne H. Blackbourne, page 469.
- ^ PMID 31571940.
- ^ PMID 11253134.
- ^ PMID 25318011.
- PMID 6424470.
- ^ Centers for Disease Control and Prevention. "About Babesiosis". CDC Parasites. Retrieved 19 June 2018.
- ^ PMID 11843905.
- PMID 8601117.
- PMID 8601117.
- ^ PMID 21651833.
- ^ "2018 Adult Schedule by Health Conditions in Easy-to-read Format for Patients". Centers for Disease Control and Prevention. Retrieved 19 June 2018.
- ^ "Immunisation of individuals with underlying medical conditions: the green book, chapter 7". Retrieved 2023-08-24.
- ^ Camille Nelson Kotton; Andrew T. Kroger; David O. Freedman. "Advising Travelers with Specific Needs". Travelers' Health. Retrieved 25 October 2018.
- PMID 7131680.
- S2CID 23790214.