SALMONELLA OSTEOMYELITIS AND ARTHRITIS IN SICKLE-CELL DISEASE

Salmonellosis is one of the most frequent serious infections in sickle cell patients and remains a significant cause of morbidity and mortality in this population. Capillary occlusion secondary to intravascular sickling may devitalize and infarct the gut, permitting Salmonella invasion. Reduced function of the liver and spleen, together with interference with reticuloendothelial system function due to erythrophagocytosis, suppresses clearing of these organisms from the blood stream. Abnormal opsonizing and complement function probably also play a role. The expanded bone marrow with sluggish flow leads to an ischemic focus for salmonella localization. The majority of Salmonella infections in sickle cell patients involve bones (especially long bones) and joints and occur most frequently in early childhood. Multiple sites, often symmetrical, are usually involved. It is imperative to distinguish Salmonella osteomyelitis from bone infarctions. While clinical and hematologic data may be suggestive, radionuclide bone imaging studies, particularly combined technetium and gallium scintigraphy and technetium sulphur colloid bone marrow scans, and magnetic resonance imaging appear more sensitive and specific. Salmonella osteomyelitis is best managed medically. Chloramphenicol, ampicillin, and trimethoprim/sulfamethoxazole have been used most frequently; however, newer beta lactams and quinolones are more active. Septic arthritis carries a poorer prognosis and often requires aggressive surgical intervention.