Haemoglobin variants in nigeria: real-world data from a point-of-care device

Abstract

Low-middle-income countries (LMICs) have used cellulose acetate electrophoresis preferentially in the diagnosis of haemoglobinopathies. Recently, point-of-care (POC) devices have made the diagnosis faster and cheaper. This study analyzed results of haemoglobin variants obtained from 'Gazelle', a POC device. A retrospective data from a tertiary hospital over a two-year period. Hereditary persistence of fetal haemoglobin (HPFH) and beta thalassaemia trait were diagnosed using a cut off of HbF of ≥ 15% and HbA2 of ≥ 3% respectively, other haemoglobin variants were as reported by the instrument. Results were compared between women accessing antenatal care and those for premarital counselling ('controls') with in-patients. A total of 1104 samples were sent for analysis during the period, but 1093 were analyzed because 11 samples were indeterminate. The distribution of the genotypes of the control was different from that of the in-patients (P = 0.02), but was comparable to that of an infant population (P = 0.71). The prevalence of HPFH and BTT were 21% (229/1093) and 36% (391/1093) respectively. The prevalence of HPFH was highest among HbSS (47.8%) compared to HbAA (22%) or HbAS (10.4%); P < 0.001. The prevalence of BTT was highest among HbAA (55.1%) compared to HbAS (5.4%) and HbSS (1.1%); P < 0.001. The prevalence of HPFH did not differ between the in-patients and the controls 23.1% vs. 19.1% respectively (p = 0.33) but the prevalence of BTT was higher among the controls (36% vs. 38%; P = 0.001). The high prevalence of sickle cell anaemia, HPFH and BTT in the community may be interrelated.