Background:

Fetal hemoglobin has been implicated in the modulation of sickle cell crisis though it is functional during infancy.

Objective:

The purpose of this study was to determine the waning time of fetal hemoglobin (HbF) and its persistence in later life.

Method:

Ninety infants aged 0-12 months; admitted at hospital; were tested for their HbF levels.Adult patients numbering 690 were also examined for their sickle cell status and a sickle positive patient of SS type with HbF had her family members recruited and their sickle cell types determined.

Results:

The results revealed that HbF was highest (98) at birth; decreasing at 5per week till 6 months when it wane off.Ten infants aged 6 -12 months had HbF persisting at a level of 10or more.Adult patients examined showed proportions of their sickle cell types as AS forming 51;AC 20; SS 19; and SC 10.An SS adult patient with mild sickle cell crisis had an ASF father who had no crisis and a mother and brother with AS each who had severe crisis.

Conclusion:

These findings suggest that HbF wanes off during infancy but persist in some adults and may modulate crisis in these adults.This has implications in sickle cell management