Foetal haemoglobin, erythrocytes containing foetal haemoglobin, and hematological features in congolese patients with sickle cell anaemia.

High HbF levels and F cells are correlated with reduced morbidity and mortality in sickle cell disease (SCD). This paper was designed to determine the HbF and F cells levels in Congolese sickle cell anemia (SCA) patients in order to determine their impact on the expression of SCD. Population and Method. HbF levels were measured in 89 SCA patients (mean age 11.4 yrs) using a standard HPLC method. F cell quantitation was done in a second group of SCA patients (n = 42, mean age 8.9 yrs) and compared with a control group (n = 47, mean age 5 yrs). F cells were quantified by a cytofluorometric system (MoAb-HbF-FITC; cut off at 0.5%). Results. The mean value of HbF was 7.2% ± 5.0 with heterogeneous distribution, most patients (76%) having HbF < 8%. Mean values of F-cells in SCA patients and control group were 5.4% ± 7.6 (median: 2.19%; range 0,0-30,3%) and 0.5% ± 1.6 (median 0.0, range 0-5.18), respectively. SCA patients with F cells >4.5% developed less painful crisis and had higher percentage of reticulocytes. Conclusion. Congolese SCA patients displayed low levels of HbF and F-cells that contribute to the severity of SCD.

Neonatal screening for sickle cell anaemia in the Democratic Republic of the Congo: experience from a pioneer project on 31 204 newborns.

BACKGROUND: Despite the high prevalence of sickle cell disease in Africa, a neonatal screening programme is available in only a few countries in the sub-Saharan region. AIM: To describe our experience of a pioneer study on 31,304 newborns screened systematically in the Democratic Republic of the Congo. METHODS: The prevalence of haemoglobinopathies was determined by a thin-layer isoelectric focusing method on dry filter-paper samples. RESULTS: Of the 31,204 newborns screened by isoelectric focusing, 5,276 (16.9%) displayed sickle cell trait and 428 (1.4%) were homozygous for haemoglobin S. No statistical differences were observed in the different ethno-linguistic groups, but some tribes displayed a higher prevalence of the betaS gene, attributable to a higher prevalence of malaria, and a greater frequency of haemoglobin S homozygotes, in part attributable to an endogamic marriage system. CONCLUSION: The neonatal screening programme has now been introduced in the Democratic Republic of the Congo, but the main challenges are to track all the new cases for a confirmatory test and to initiate early management.