When the Inheritance of two Heterozygote States become a Diagnostic Problem : Misdiagnosis of the Sickle Cell Trait

ABSTRACT

BACKGROUND: The sickle cell trait is a benign asymptomatic condition that should not ordinarily be associated with clinical manifestations of a haemoglobinopathy. METHOD: This is a case control study of sickle cell trait patients who presented with symptomatology of a haemoglobinopathy. HbA2; HbF and HbS levels as well as the haematocrit and the peripheral film pictures of 10 symptomatic individuals (patients) with the sickle cell trait were compared with those of 20 asymptomatic individuals (controls) with the sickle cell trait. RESULTS: the mean HbA2 of the cases was 4.9compared to the mean of 2.2 for the controls (p0.0001). Nine of the patients and none of the controls had a raised HbA2 ( 3.5). The mean HbF of the patients was 5.6 with a range of 1.2-14.0 while the mean of the control was 2.0 and a range of 0.7-8.4 (p=0.006). Six (30) of the controls had normal HbF level (1) while none of the patients had a normal HbF level. The mean haematocrit of the patients and controls were 0.33 and 0.37 respectively (p