EVIDENCE-BASED ANSWER
Immunization against encapsulated bacterial pathogens decreases the incidence of post-splenectomy sepsis. Pneumococcal, meningococcal, and Haemophilus influenzae (Hib) vaccinations are indicated for patients after splenectomy. These immunizations should be given at least 14 days before a scheduled splenectomy, or given after the fourteenth postoperative day (strength of recommendation [SOR]: A, based on systematic review of RCTs for the pneumococcal vaccine; SOR: B, based on systematic review of clinical trials for meningococcal and Hib vaccines).
CLINICAL COMMENTARY
Don’t forget those on prednisone, immunosuppressants, or undergoing chemotherapy
David Cravens, MD
University of Missouri–Columbia
This is an important and often overlooked component of preventive care—what to do with an asplenic patient? Individuals with functional asplenia from sickle-cell disease or other causes should also probably be included in this vaccination/revaccination schedule.
Another patient group that may require a more considered approach is those residing in long-term care facilities. Attention to immunizations may be even more important to a frail elder’s health in an institutional setting: vaccinations historically have been overlooked in this group, and certainly revaccination could be even more easily missed. I have occasionally discovered I was caring for an asplenic patient in the nursing home upon reviewing that patient’s medical history with a close family member or caregiver.
Additionally, elders on chronic immunosuppressant therapy or prednisone for rheumatoid arthritis or other autoimmune disorders, and those on chemotherapy for malignancies should also be revaccinated with pneumococcal vaccine approximately every 5 years.
Evidence summary
Asplenic individuals are known to be at an elevated risk for infection with encapsulated bacteria. The lifetime risk of post-splenectomy sepsis is estimated to be approximately 1% to 2%. The overwhelming majority of these cases are caused by Streptococcus pneumoniae, Haemophilus influenzae, and Neisseria meningitides.1-4
In 2 recent RCTs, the 23-valent pneumococcal polysaccharide vaccine was tested on patients 1, 7, 14, and 28 days after splenectomy.1,2 The studies demonstrated that the immunogenicity of the vaccine was best when given at or after day 14 after the operation. In both studies, patients immunized at day 14 had immunoglobulin G (IgG) antibody levels approaching those of control subjects with intact spleens. There were no differences in antibody levels among those patients immunized at day 14 compared with those immunized on day 28. However, those subjects immunized on days 1 and 7 had significant lower antibody levels than the control subjects or those immunized on day 14.