RESUMO
The association between the clinical outcome of chloroquine treatment and mutations in the putative Plasmodium falciparum chloroquine resistance transporter (Pfcrt) gene at codon 76 and multidrug resistance gene 1 (Pf mdr1) at codon 86 were investigated among 406 children with uncomplicated malaria presenting at five sentinel health centres in Ghana. Presence of mutations in isolates taken at pre-treatment and on day of recurrence of parasites was detected using PCR followed by RFLP techniques. The prevalence of Pfcrt T76 mutants was 80% at Hohoe, 46% at Navrongo, 98% at Tarkwa, 61% at Sunyani and 46% at Yendi. The prevalence of the mutant Pfmdr1 at Hohoe, Navrongo, Tarkwa, Sunyani and Yendi were 78, 58, 95, 53 and 42%, respectively. Significant association between the Pfcrt mutation and treatment outcome was observed at Hohoe and Sunyani (p < 0.05), but not at Navrongo, Tarkwa or Yendi (p > 0.05). Similarly, a statistical significant association between Pfmdr1 86 and treatment failures was observed at Hohoe and Sunyani (p < 0.05) but not at the other three sites. A positive correlation was found between mutant Pfcrt prevalence only and treatment failures with a Spearman's rho-value of 0.872 and a p-value = 0.027. All parasite isolates from samples taken at recrudescence from patients with chloroquine treatment failures were found to have both Pfcrt and Pfmdr mutations.