High Prevalence of Plasmodium Falciparum pfcrt K76T Mutation in Children with Sickle cel Disease at a Tertiary Hospital in North-western Tanzania

The high prevalence of sickle cel disease (SCD) and trait in Sub-Saharan Africa coincides with the distribution of Plasmodium falciparum malaria. Due to prolonged heavy use of chloroquine (CQ) as an antimalarial, drug resistance has developed. Many countries including Tanzania abandoned the use of CQ for uncomplicated malaria, except its use as prophylaxis in patients with sickle cel disease. This study investigated the prevalence of malaria in SCD patients and mutations asociated with CQ resistance. Children diagnosed with sickle cel disease atending both outpatient clinic and those admited at Bugando Medical Centre in north-western Tanzania were screned for malaria using thick blod smear. A dried blod spot on Whatman filter paper was also taken for polymerase chain reaction (PCR) and restriction fragment length polymorphism. Among 123 known patients with sickle cel disease, the prevalence of malaria by blod smear microscopy was 3.2% and by PCR was 13.8%. The prevalence of K76T mutation among the patients was 81.3%. The majority of the patients (72.4%) were using chloroquine prophylaxis. In conclusion, the prevalence of malaria parasitaemia among children with sickle cel disease atending BMC is low (3.2%) by microscopy but several children maintain sub patent infection detectable by PCR. The prevalence of chloroquine resistant P. falciparum in these children was higher than that previously sen in normal population in Tanzania. We recommend special atention to be paid to patients with sickle cel disease while studying the dynamics of drug resistant parasites.