CERTAIN RED CELL GENETIC FACTORS AND PREVALENCE OF CHLOROQUINE - INDUCED PRURITUS

Abstract

The hypoihcsis that chloroquinc-induccd pruritus (CIP) may bo determined by certain genetic factors was tested by investigating the epidemiology of C1P with respect to certain genetic red ccll markers namely, haemoglobin genotype , glucosesphosphate dehydrogenase (G6PD) deficiency and the ABO blood groups. Three hundred consecutive patients treated for malaria with chloroquine at the University College Hospital, Ibadan, Nigeria were rccruitcd into the study. They were observed over 3 days for presence of CIP. ABO blood groups G6PD and Hb genotypes were determined appropriately for each patient. One hundred and twenty four (41.3%) of the patients responded positively to CIP. There was a reduced frequency of the sickle ccll trait (HbAS) among itchcrs relative to non-itchcrs. This suggests that the trait may be protective against CIP. G6PD deficiency was also found to be relatively more common among itchers than non-itchcrs. This indicates that G6PD deficiency may incrca.se susceptibility to CIP. There was however no dif ference in the distribution of itchcrs among the different ABO blood groups. It was concluded that CIP may be associated with certain genetic red cell markers particularly Hb and G6PD types which arc known malaria markers but not ABO blood groups.