Sickle cell disease in Sierra Leone: a clinical and haematological analysis in older children and adults.

A prospective study of the clinical and haematological features of sickle cell disease in 121 Sierra Leonean patients (106 SS: sickle cell anaemia; 15 SC: sickle cell haemoglobin C disease) was undertaken. Fifty-five per cent of the patients were Creoles who were descendants of liberated slaves and who therefore had strong ethnic and genetic relationships with West Indians and black Americans. No essential differences were noted between the Creoles and non-Creole Sierra Leonean patients. The general clinical features and the patterns of vaso-occlusive crises were similar to those of black American, Jamaican and other West Africans (Ghanaians and Nigerians). However the incidence of certain complications such as avascular necrosis of the femoral head was higher in Sierra Leoneans (8.5% SS, 20% SC) than in other West Africans e.g. Ghanaians (2.8% SS, 6.6% SC) but similar to that of Jamaicans (8.2% SS, 18% SC). Also the frequency of leg ulceration in Sierra Leonean sickle cell patients (13.2% SS, 13.3% SC) was relatively low when compared to patients in the United States of America (73.6% SS) and Jamaica (63.3% SS) but relatively high in comparison to Nigerian (5.4% SS + SC + S beta-thal) and Ghanaian (10.6% SS, 2.2% SC) patients. The causes for such varying manifestations are probably environmental. The haematological features of the Sierra Leonean patients were similar to those of other population groups in all essential aspects.