Onyalai in Namibia. Clinical manifestations, haematological findings, course and management of 103 patients in the Kavango territory
A series of 103 patients with onyalai, from the Kavango territory in Namibia, is recorded. In addition to haemorrhagic bullae in every patient, epistaxis was present in 53, petechiae and ecchymoses in 23, subconjunctival or scleral bleeds in 17, melaena and haematemesis in 16, haematuria in 12 and menorrhagia in 9 patients. The male:female ratio was 43:60. The ages varied from 6 months to 70 years with a peak incidence between 11 and 20 years. The mean platelet count was 22 × 109/l and the mean haemoglobin 10·3g/dl on admission. The management consisted of the correction of blood loss. A splenectomy in 2 patients with uncontrollable haemorrhage caused a rise in the platelet count. Prednisolone and intravenous gammaglobulin had the same effect on the platelet count as ascorbic acid (placebo). Vincristine sulphate appeared to benefit some patients. One year's observation of 21 patients demonstrated that 80% of cases will have chronic thrombocytopenia with a risk of intermittent attacks of acute haemorrhage. Six patients died, 4 of cerebral haemorrhage and 2 of haemorrhagic shock. Four infants born to mothers with onyalai were normal at birth. Onyalai should be clearly distinguished from classical idiopathic thrombocytopenic purpura, a disease also encountered in Africa. © 1987.