The value of foetal haemoglobin level in the management of nigerian sickle cell anaemia patients.

OBJECTIVE: This study was designed to determine the influence of foetal haemoglobin (HbF) concentration on the frequency of painful crisis, blood transfusion and other complications.
METHOD: A prospective study of SCA patients in steady state and vaso-occlusive crisis (VOC) seen between August 2001 and July 2002 in 3 centers in Benin City, Nigeria. Two hundred patients (81.3% ) in steady state and forty-six patients (18.7%) in VOC were analysed in the context of gender, age, the frequency of VOC, number of blood transfusions and complications e.g. osteomyelitis, leg ulcer, cholelithiasis etc in the preceding one-year after informed consent. Eighty-four age and sex matched controls were also recruited. Their blood samples were analysed within two hours of collection for HbF using the Betke method and haemoglobin and haematocrit levels using the Automated Coulter Counter.
RESULTS: The mean HbF in steady state, VOC and control were 2.17% +/- 1.81, 2.05%+/-1.19 and 1.28%+/-1.04 respectively. There was no significant difference (P>0.05) between HbF values in VOC and steady state periods but they were significantly higher than in control (P<0.01). The mean %HbF was significantly higher in patients who had no painful crisis (2.14% vs 1.55%, P=0.0023), those who had no complications (2.45% vs 1.12%, P<0.0001) and those who did not have blood transfusion (2.41% vs 0.68%, P<0.0001) in the preceding year than those who did. Conclusion-There is no significant difference in foetal haemoglobin values in steady state and vasoocclusive crisis. A higher level of foetal haemoglobin was associated with fewer painful crises, less complications and reduced need for blood transfusion. Key words: foetal haemoglobin, crisis, complications, transfusions.