Unstable-haemoglobin haemolytic anaemia.

A 6-year-old girl suffering from chronic haemolytic anaemia with crisis induced by drugs and infections is described. The disorder was diagnosed as an unstable-haemoglobin haemolytic anaemia. The heat stability test, simple and specific for unstable haemoglobins is mentioned, it should be done in every child suffering from unexplained chronic haemolytic anaemia. The haemoglobin variant is also known in a patient in Brazil as Hb Niteroi.