title: Factors contributing to the development of anaemia in Plasmodium falciparum malaria: what about drug-resistant parasites?
abstract: A major manifestation of complicated malaria especially among children is severe anaemia, the pathogenesis of which is not well understood. Among other factors, suppression of the bone marrow's response to erythropoietin, which is rapidly reversed after successful treatment of the malaria, has been implicated in its pathogenesis. Since resolution of malaria restores erythropoiesis, we hypothesized that drug-resistant strains of Plasmodium falciparum would increase the risk of severe anaemia developing from initially uncomplicated malaria. Using both in vivo and in vitro drug-sensitivity tests we compared the prevalence of drug-resistant malaria between severe malarial anaemia SA and non-anaemic malaria NAM patients. Assessment of treatment outcome using the WHO in vivo criteria showed no significant difference in parasite resistance between the two groups. The mean parasite clearance time was also comparable. Treatment failures of about 14 per cent and 12 per cent were observed between SA and NAM patients respectively. The in vitro drug susceptibility test showed overall mean IC50 values of 0.41x10(-6) mol/l and 0.32x10(-6) mol/l blood for SA and NAM groups respectively. Geometric mean pre-treatment blood levels of chloroquine did not differ much between the two groups. Findings from this study could not therefore implicate drug-resistant parasites in the pathogenesis of severe malarial anaemia.
authors.affiliation: Centre for Tropical Clinical Pharmacology and Therapeutics, University of Ghana Medical School, Accra, Ghana. nquashie@noguchi.mimcom.net
authors.forename: Neils Ben
authors.initials: NB
authors.lastname: Quashie
authors.forename: Bartholomew D
authors.initials: BD
authors.lastname: Akanmori
authors.forename: David
authors.initials: D
authors.lastname: Ofori-Adjei
authors.forename: Bamenla Q
authors.initials: BQ
authors.lastname: Goka
authors.forename: Jorgen A L
authors.initials: JA
authors.lastname: Kurtzhals
mesh_terms: D000655:Amodiaquine / Q000627:therapeutic use; D000740:Anemia / Q000469:parasitology*; D000818:Animals; D037621:Artemisinins / Q000627:therapeutic use; D000077332:Artesunate; D002648:Child; D002675:Child, Preschool; D002738:Chloroquine / Q000627:therapeutic use; D004351:Drug Resistance; D004359:Drug Therapy, Combination; D006801:Humans; D007223:Infant; D008288:Malaria / Q000097:blood* / Q000150:complications / Q000188:drug therapy / Q000469:parasitology; D010963:Plasmodium falciparum; D012717:Sesquiterpenes / Q000627:therapeutic use
chemical_list: D037621:Artemisinins; D012717:Sesquiterpenes; D000655:Amodiaquine; D000077332:Artesunate; D002738:Chloroquine