By far the most common is Streptococcus pneumoniae, which can cause life-threatening infection. Lifelong Penicillin is taken.
Indications for Splenectomy
- Hereditary spherocytosis
- Idiopathic thrombocytopenic purpura
- Myelofibrosis as grossly enlarged.
Medical causes of Hyposplenism
- Sickle cell anaemia
- Coeliac disease
- Blood film mimics post splenectomy
Following splenectomy a person is at risk of
- Streptococcus pneumoniae
- Haemophilus influenzae
- Neisseria meningitidis
- Escherichia coli
- Pseudomonas aeruginosa.
Post splenectomy blood films
- Acanthocytes (spiky red cells)
- Target cells (like an archery target)
- Pappenheimer bodies (iron granules)
- Howell–Jolly bodies (nuclear DNA fragments)
Risks of Hyposplenism
- Overwhelming post-splenectomy infection (OPSI) is the most feared complication of hyposplenism.
- Risk of overwhelming pneumococcal sepsis
Prevention of Post Splenectomy/Hyposplenic infection
- Pneumococcal vaccination with pneumococcal conjugate vaccine is more effective, because it utilizes a T cell dependent mechanism, and should be the preferred vaccine in these circumstances. Check check adequacy of antibody response and repeat antibody levels at 5 years post vaccination and give booster doses if appropriate.
- Promptly and aggressive treatment of pneumococcal sepsis
- Meningococcal conjugate (ACWY) series and monovalent meningococcal serogroup B vaccine series.
- Usually Pneumococcal but other encapsulated bacteria e.g.
Haemophilus influenzae type B and Neisseria meningitidis and protozoa have been reported.
- Life-long prophylactic antibiotic therapy, e.g. penicillin V 250 mg BD
- Mortality rate due to Strep. pneumoniae is 50% despite treatment
- Increased risk for vascular, autoimmune and thrombotic diseases and they may
Organisms to know in hyposplenic patients
- Streptococcus pneumoniae (>80%).
- Haemophilus influenzae type B.
- Neisseria meningitidis.
- Malaria (mosquitos)
- Babesiosis (tick bites)
- Capnocytophaga canimorsus (dog bites)