Haemoglobin Leiden in a South African negro. A case report.

A Black patient in whom an acute febrile illness was followed by a haemolytic crisis is presented. Investigation of the haemolytic anaemia showed the presence of an unstable haemoglobin which was found to be haemoglobin Leiden. Those members of the family who were available for investigation also had the unstable haemoglobin but showed no haemolysis. Radio-isotope studies on the patient confirmed haemolysis but showed that the spleen was not the main site of cell destruction.