Overwhelming Post-Splenectomy Infection (OPSI) Guidelines

Introduction to OPSI

OPSI is a fulminant, life-threatening infection that occurs in patients without a functioning spleen, presenting as rapidly progressive sepsis, meningitis, or pneumonia primarily caused by encapsulated bacteria, with mortality rates of 30-70% even with treatment 1
OPSI represents a true medical emergency where patients can progress from mild flu-like symptoms to fulminant septic shock within hours, with most deaths occurring within the first 24-48 hours of symptom onset 1, 2

Streptococcus pneumoniae accounts for approximately 50% of all OPSI cases 1, 2
Haemophilus influenzae type B is significant, particularly in children 3
Neisseria meningitidis is associated with serious infection 3
Children under 5 years—especially infants—face dramatically higher risk with infection rates exceeding 10%, compared to less than 1% in adults 3
The risk is highest in the first year after splenectomy but remains elevated for more than 10 years and is almost certainly lifelong 1, 2

OPSI typically begins with nonspecific symptoms including fever, malaise, chills, headache, and myalgias that rapidly progress to fulminant septic shock, meningitis, pneumonia, disseminated intravascular coagulation, and multi-organ failure 2
All asplenic patients must receive vaccination against encapsulated bacteria, including pneumococcal, meningococcal, and Haemophilus influenzae type B vaccines 2
Lifelong prophylactic antibiotics should be offered to all patients, with highest priority in the first 2 years post-splenectomy 5, 2
Patients must also have emergency standby antibiotics at home to use immediately at the first sign of fever, malaise, or chills 5, 1

Every asplenic patient must understand their lifelong increased risk of life-threatening infection, the need for immediate medical attention with any fever >101°F (38°C), and the importance of carrying medical alert identification indicating asplenic status 2
Failing to vaccinate before elective splenectomy, assuming the risk diminishes over time, not providing emergency standby antibiotics for home use, inadequate patient education, and forgetting that functional hyposplenism carries the same risk as surgical splenectomy are common pitfalls to avoid 2, 1