Sulfadoxine-pyrimethamine resistant falciparum malaria in Thai children

Abstract

Sixty-eight children with uncomplicated falciparum malaria admitted to the Hospital for Tropical Diseases in Bangkok during April-December1980 were randomly divided into 3 groups and given 3 regimens. Group 1 of 27 cases were treated with a single dose of sulfadoxine (20 mg per kg body wt) and pyrimethamine (1.0 mg per kg body wt.) Two cases (7.4%) were cured (S) while 4 cases (14.8%) showed RI failure, 17 cases (63.0%) RII failure and 4 cases (14.8%) RIII failure. In Group 2, 18 cases were treated with a single dose of sulfadoxine (30 mg per kg body wt) and pyrimethamine (1.5 mg per kg body wt). Two cases (11.1%) were cured (S), while 7 cases (38.9%) showed RI failure, 7 cases (38.9%) RII failure and 2 cases (11.1%) RIII failure. In Group 3, 23 cases were treated with quinine (10 mg base per kg body wt) 8 hourly for 5 days plus sulfadoxine (20 mg per kg body wt) and pyrimethamine (1.0 mg per kg body wt), single dose given with the last dose of quinine. Thirteen cases (56.5% were cured (S), while 10 cases (43.5%) showed RI failure. This study shows that the sensitivity of P. falciparum malaria to sulfadoxine/pyrimethamine alone or with quinine is decreasing in Thailand.