Dr. Murai Éva szerk.: Parasitologia Hungarica 26. (Budapest, 1993)

daily dose of 22.5 mg/kg, good hospital conditions and careful monitoring of the electrolyte status as well as of heart function by electrocardiography (ECG) are needed because of the drug's effects on the heart. The authors of this study used a combination of quinine and its dextrorotary stereoisomer quinidine for the treatment of chloroquine-resistant P.f. malaria cases of medium to high severity. The combination made it possible to reduce the daily dose of quinidine and, thereby, to avoid its side effects. Treatment with this combination renders hospitalization unnecessary. MATERIALS AND METHODS This study was carried out as a randomized trial involving 54 adults aged between 20-56 years and infected by P.f. strains from the highly chloroquine-resistant malaria endemic region of South Vietnam (Song Be, Dong Nai). The patients were admitted to Hospital Cho Ray in Ho Chi Minh City between 15 December 1988 and 20 February 1989. All patients were affected by malaria of medium to high severity. Patients with coma or renal failure were excluded from the study. The criteria of inclusion were the following: living in an area where chloroquine-resistant malaria was endemic (Dong Nai, Song Be); having P.f. parasitaemia between 1,000 and 100,000 parasites per microlitre of blood (asexual forms of parasites); no Plasmodium vivax or mixed infection; no heart failure; not on digitalis or antiarrhythmic treatment; no vomiting. The patients were divided into 2 groups and subgroups within each group. Group la: 10 patients received chloroquine phosphate at a dose of 25 mg/kg, recommended by the World Health Organization (WHO) schedule, together with 40 mg of verapamil (IV) every 8 hours, for 3 days. Group lb: 10 patients received chloroquine phosphate, at the same dose as la, with 80 mg of verapamil (2 V), every 8 hours, for 3 days (Table 1). The second group contained 25 patients, divided into subgroups a and b. Ifen patients (group 2a) were resistant cases (RI, RII and RIII) from subgroups la and lb. They received a quinine + quinidine combination (300 mg of quinine sulphate and 200 mg of quinidine sulphate) orally, every 8 hours. Treatment with the quinine + quinidine combination was started 48 hours after the failure of chloroquine + verapamil treatment, and was continued for 5 days. Fifteen patients of group 2b were treated at once by quinine + quinidine sulphate. The quinine + quinidine combination was administered orally, at the same standard dose as in group 2a, every 8 hours, for 5 days. Groups 3 and 4 served as control groups. Group 3 comprised 10 patients who received only quinine sulphate at a dose of 10 mg/kg every 8 hours for 7 days. Group 4 consisted of 10 patients who received chloroquine phosphate at a total dose of 25 mg/kg, as recommended by the WHO schedule. The period of observation was 28 days. Blood smears were taken every twelve hours until the asexual forms of the parasites were cleared, and blood sampling was then repeated daily in the morning. The diagnosis was established using Giemsa-stained thick and thin film (blood smear positive for P.f. asexual form). Parasitaemia was counted on white blood cells and calculated per microlitre of blood. Haematological examination: red blood cell count, platelet and white blood cell count, haematocrit, sedimentation rate. Biochemical