Asplenic

Aka: Asplenic, Asplenia, Functional Asplenia, Asplenism, Hyposplenism, Hyposplenic, Postsplenectomy

1. See Also
   1. Postsplenectomy Sepsis
2. Causes: Hyposplenism or Asplenism
   1. Common Surgical Causes
      1. Splenectomy
      2. Partial Splenectomy
   2. Common Medical Causes
      1. Celiac Disease
      2. Cirrhosis
      3. Sickle Cell Anemia
      4. Vasculitis
      5. Systemic Lupus Erythematosus
      6. Bone Marrow Transplantation
      7. Splenic irradiation in Hodgkin's Disease
   3. Other Causes of Hyposplenism
      1. Cyanotic heart disease
      2. Ulcerative Colitis
      3. Whipple's Disease
      4. Chronic active hepatitis
      5. Acute Alcohol Abuse
      6. Hemoglobinopathy
      7. Primary Thrombocythemia
      8. Fanconi's Syndrome
      9. Malignant histiocytosis
      10. Rheumatoid Arthritis
      11. Grave's Disease
      12. Sarcoidosis
      13. Splenic arterial or venous Occlusion
      14. HIV Infection
      15. Total Parenteral Nutrition
      16. High dose Corticosteroids
3. Pathophysiology: High Risk Organisms
   1. Encapsulated Bacteria
      1. Streptococcus Pneumoniae
      2. HaemophilusInfluenzae
      3. Neisseria Meningitidis
   2. Gram Negative Bacteria
      1. Capnocytophaga canimorsus (Dog Bites)
   3. Intraerythrocytic parasites
      1. Plasmodia falciparum (Malaria)
      2. Babesia microti (Babesiosis)
   4. Less common organisms
      1. Group B Streptococcus
      2. Enterococcus
      3. Bacteroides
      4. Salmonella
      5. Bartonella
      6. Plesiomonas shigelloides
      7. Eubacterium plauti
      8. Pseudomonas pseudomallei
4. Diagnostics to identify Hyposplenism
   1. Step 1: History suggests possible Hyposplenism
      1. Known post-Splenectomy: See Management below
      2. Possible Hyposplenism: Go to Step 2
   2. Step 2: Peripheral Smear shows Howell-Jolly Bodies
   3. Step 3: Abdominal Ultrasound if smear positive
      1. Spleen absent
         1. See Management below
      2. Spleen present
         1. Radionuclide liver-Spleen scan
   4. Step 4: Radionuclide liver-Spleen scan
      1. Normal Uptake
         1. Normal splenic function
      2. Decreased or absent splenic uptake
         1. See management below
5. Management: Prevention
   1. Initial Immunizations
      1. Timing
         1. Preferred >14 days before elective splenectomy
         2. Otherwise administer on diagnosis
      2. Immunizations
         1. Pneumococcal Vaccine
            1. PPV-23 (Pneumovax) for adults and children who completed PCPV-7
            2. PCPV-7 (Prevnar) for children and adults who Overwhelming Postsplenectomy Infection
         2. Meningococcal Vaccine (Menactra)
            1. Two dose series (with 2 month interval) and
            2. Future boosters every 5 years
         3. Haemophilus B Conjugate Vaccine
            1. Primary Series in children (four doses)
            2. No guidelines on booster Immunization in Asplenic adults
   2. Repeat Pneumococcal Vaccine (PPV-23) after age 10 years
      1. Every 5 years for most Asplenic patients
      2. Every 3 years for early waning Antibody titers
         1. Hypogammaglobulinemia
         2. Sickle Cell Anemia
         3. Nephrotic Syndrome
         4. Chronic Renal Failure
   3. Documentation and Education
      1. Medic-Alert Bracelet
      2. Update medical record
         1. Vaccinations
         2. Asplenism
      3. Patient educated on infectious risks of Asplenism
         1. Immediate evaluation for febrile illness
         2. Notify dentists and doctors of Asplenic state
         3. Exposure risks
            1. Travel (Malaria)
            2. Tick Bites (Ehrlichia and Babesiosis)
            3. Dog Bite
6. Management: Antibiotics for prophylaxis or as Stand-by at first signs of infection
   1. Antibiotics: Daily prophylaxis
      1. Amoxicillin
      2. Penicillin
      3. Trimethoprim-Sulfamethoxazole (Bactrim)
   2. Antibiotics: Stand-by Antibiotics
      1. Amoxicillin-Clavulanate
      2. Cefuroxime (Zinacef)
      3. Levofloxacin (Levaquin) - in adults
   3. Protocols
      1. Children with Asplenism or Hyposplenism
         1. Daily Prophylaxis
         2. Duration controversial (options below)
            1. First 2-5 years after splenectomy
            2. Continued until age 21 years
            3. Continue daily prophylaxis if history of Overwhelming Postsplenectomy Infection
      2. Adults with Asplenism or Hyposplenism
         1. Continue daily prophylaxis if history of Overwhelming Postsplenectomy Infection
         2. Standby antibiotics taken at first signs infection (fever)
            1. Augmentin or
            2. Levofloxacin
         3. Immediate medical evaluation mandatory
            1. Well-appearing: Obtain cultures and continue antibiotics for 7-10 days
               1. Consider 24 hour follow-up
            2. Suspect Sepsis: Admit immediately and start IV antibiotics
               1. See Overwhelming Postsplenectomy Infection
7. Management: Acute Infection
   1. See Overwhelming Postsplenectomy Infection
8. References
   1. Brigden (2001) Am Fam Physician 63(3):499-506
   2. DeRossi (1996) J Am Dent Assoc 127:1359-63
   3. Doll (1987) South Med J 80:999-1006
   4. Sumaraju (2001) Infect Dis Clin North Am 15(2):551-65
   5. (1996) BMJ 312:430-4