[Infection and immunity in sickle cell disease].

There is a high incidence of bacterial infections in sickle cell disease, particularly in sickle cell anemia. Pneumonia, urinary tract infections, osteomyelitis, meningitis and pneumococcal septicemia occur mainly in younger patient. The pathological basis for this susceptibility to infections is complex. Defective splenic function is the most important factor. There are also abnormalities of opsonization, alternate complement pathway, antibody production, leucocyte function, and cell-mediated immunity. Pneumococcal immunization and prophylactic penicillin are indicated in the prevention of pneumococcal infections.