Beta thalassaemiatriat in Western Nigeria

Background: Genes for thalassaemia; haemoglobin S; Glucose-6-phosphate dehydrogenase which confer resistance to malaria are found in high frequencies in Nigeria; 25of the population being carriers of the sickle cell trait while another 25are hemizygous for the G6PD gene. The frequency of alpha thalassaemia is equally high among Nigerians but there is little information on beta thalassaemia in this population. A recent study however suggest a high prevalence of beta thalassaemia in the same population; hence the need for this study. Methods: Haemoglobin A2 and HbF were determined in healthy adults who have haemoglobin A genotype by elution after electrophoresis and alkaline denaturation methods respectively. Results: The mean HbA2 among the subjects was 3.3(range 2.0-5.6) while the mean HbF was 2.6(range 0.4-8.8). Twenty-six percent of the subjects had HbA2 values higher than 3.9while 86had HbF values greater than 1; twenty-four percent had elevated HbA2 and HbF. The mean HbA2 value was 2.7among those with HbF 1; 3.6among those with HbF 1-3and 3.1among those with HbF 3. Conclusion: These findings confirm that the frequency of beta thalassaemia in western Nigeria is higher than previously thought and that many of the individuals studied may be silent carriers of the beta thalassaemia trait. Its presence may also have been masked by the high prevalence of alpha thalassaemia in the same environment. It is therefore important to consider beta thalassaemia trait as a differential diagnosis in patients who present with haemolytic anaemia in this environment

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

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