: Immunization and OPSI
OPSI: Overwhelming Post-splenectomy Infection
3-5% lifetime risk
0.2-0.4% annual risk
Risk highest in first year (adults ~1%, children ~5%)
Lower in trauma
Higher in haematological disorders
- especially immunocompromised
Higher in extremes of age
Caused by decreased antigen clearance
Strep pneumoniae most common agent, often begins with urti that soon
becomes severe sepsis.
- recovered in 50-90% of isolates
Then: H. Influenza B, Strep B, Staph aureus, E. coli, other
N Meningitidis risk is not well clarified
Emergencies; require immediate IV antibiotics and intensive care.
Mortality approaches 40%
Optimal at 14d prior to surgery
If they did not receive it before surgery then can give it just
- however, probably better after several weeks as improved immune
- pneumococcal, meningicoccal, and Haemophilus.
- pneumovax protects against 75% active organisms; others unproven
Current guidelines favours pneumovax booster every 5-10 years.
- some also recommend meningococcus ever 5y
- H influenzae AB titres can be monitored to asses need for booster
Counselling and Antibiotics
Warn all patients regarding OPSI risk.
Seek immediate care if develop febrile illness.
Long term prophylactic antibiotics remains controversial.
- promotes resistant strains.
Evidence supports use in selected child populations but no evidence
yet in adults.
--> Discharge patients with a supply of oral antibiotics with
clear instructions to initiate therapy with onset of infective
symptoms while seeking medical aid.
--> In children, common to do 2y prophylaxis
Beware dog bits - capnocytophaga canimorus
If travelling to malarial areas, need cautious prophylaxis