What is overwhelming post‑splenectomy infection (OSPI) and what pre‑operative and post‑operative care is required for patients undergoing splenectomy?

Overwhelming Post-Splenectomy Infection (OPSI) and Perioperative Care

What is OPSI?

OPSI is a syndrome of fulminant sepsis occurring in asplenic or hyposplenic patients, characterized by rapid progression to shock and death, with mortality rates reaching 45-50% even with treatment. 1, 2 The infection typically presents with flu-like symptoms that deteriorate within 24 hours to overwhelming sepsis, purpura fulminans, and multi-organ failure. 3

Key Characteristics:

• Causative organisms: Streptococcus pneumoniae causes approximately 90% of cases, followed by Haemophilus influenzae, Neisseria meningitidis, and occasionally Gram-negative bacteria like E. coli. 1, 2, 4
• Timing: While most infections occur within the first 2 years post-splenectomy, up to one-third manifest after 5 years, with documented cases occurring 20-65 years after surgery. 5, 6, 4
• Risk is lifelong: The infection risk remains clinically significant throughout the patient's lifetime. 5

High-Risk Groups:

• Children under 5 years (especially infants) have infection rates exceeding 10%, compared to <1% in adults. 5
• Patients with lymphoproliferative disorders, myeloma, or sickle cell disease face particularly elevated risk. 5
• Those with underlying immunosuppression or hyposplenia from conditions like celiac disease or inflammatory bowel disease. 5, 7

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Pre-Operative Care

Vaccination (Minimum 2 Weeks Before Surgery):

All vaccines must be administered at least 2 weeks before elective splenectomy to ensure optimal antibody response. 5

• Pneumococcal vaccine: 23-valent polysaccharide vaccine (>90% effective in healthy adults under 55). 5
• Meningococcal vaccine: Safe for both children and adults. 5
• Haemophilus influenzae type b vaccine: Should be included in the vaccination protocol. 8
• Influenza vaccine: Recommended yearly to reduce risk of secondary bacterial infection (avoid in pregnancy). 5, 8

Patient Education Before Surgery:

• Explain the lifelong risk of overwhelming infection and the need for immediate medical attention with any febrile illness. 9
• Provide written documentation (card or letter) that the patient should carry at all times documenting their splenectomy status. 9, 6
• Discuss the importance of compliance with prophylactic antibiotics and vaccination schedules. 8

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Post-Operative Care

Antibiotic Prophylaxis:

Lifelong prophylactic antibiotics should be offered in all cases, with mandatory use during the first 2 years post-splenectomy when risk is highest. 5

Specific Regimens:

• First-line: Oral phenoxymethylpenicillin (penicillin V) daily. 5
• Penicillin allergy: Erythromycin as alternative. 5
• Duration:
  • Children and adolescents: Always for minimum 3 years. 9
  • Adults: Minimum 2 years, but lifelong prophylaxis is recommended. 5, 8

Emergency Antibiotic Supply:

• Patients should keep a supply of amoxicillin at home to use immediately if symptoms of infection develop, before seeking medical attention. 5
• Educate patients to start antibiotics at first sign of fever or illness while simultaneously seeking urgent medical care. 9

Vaccination Schedule Post-Operatively:

For unimmunised patients (emergency splenectomy), vaccinate at the first opportunity post-operatively. 5

Reimmunisation Protocol:

• Pneumococcal vaccine: Reimmunise every 5-10 years. 5
• High-risk patients (children under 2, sickle cell disease): Consider reimmunisation as early as 2-3 years after initial dose due to more rapid antibody decline. 5

Ongoing Monitoring and Documentation:

• Notify the general practitioner immediately about the splenectomy and all vaccinations given to coordinate care and avoid premature reimmunisation reactions. 5
• Establish asplenic patient registers to ensure compliance with preventive measures and enable audit of outcomes. 2
• Annual influenza vaccination should continue indefinitely. 5, 8

Patient Education (Ongoing):

Long-term patient education is the cornerstone of OPSI prevention and remains mandatory throughout the patient's life. 8

• Reinforce the need for immediate medical attention with any febrile illness or signs of infection. 1, 9
• Ensure patients understand that infections can progress from flu-like symptoms to death within 24 hours. 3
• Emphasize carrying medical alert documentation at all times. 6

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Common Pitfalls to Avoid

Critical Gaps in Current Practice:

Current best practice guidelines are not being followed in the majority of cases, with only 31% of OPSI patients having received pneumococcal vaccination before infection. 2

• Only 22% of asplenic patients take any chemoprophylaxis, and most do not carry medical alert cards. 6
• Many asplenic individuals remain unrecognized in the healthcare system, preventing implementation of preventive measures. 2
• Seven of 17 pneumococcal infections in one study occurred despite vaccination, indicating some vaccine failures do occur. 2

Specific Actions to Prevent Failures:

• Do not delay vaccination in elective cases—the 2-week pre-operative window is critical for antibody development. 5
• Do not assume vaccination alone is sufficient—antibiotic prophylaxis is essential, particularly in the first 2 years. 5, 8
• Do not underestimate the risk in older patients or those many years post-splenectomy—OPSI can occur decades later. 6, 4
• Recognize that non-encapsulated organisms like E. coli can also cause OPSI, particularly in immunosuppressed patients. 4