[Therapeutic response of Plasmodium vivax to chloroquine in Bolivia].

Abstract

INTRODUCTION:

Knowledge of the therapeutic efficacy of chloroquine for Plasmodium vivax infections improves the capacity for surveillance of anti-malarial drug resistance.

OBJECTIVE:

The therapeutic efficacy of chloroquine as treatment was evaluated for uncomplicated Plasmodium vivax malaria in Bolivia.

MATERIALS AND METHODS:

An in vivo efficacy study of chloroquine was undertaken in three regions of Bolivia--Riberalta, Guayaramerín and Yacuiba. Two hundred and twenty-three patients (84, 80, and 59 in the three regions, respectively) aged over 5 years old were administered with chloroquine (25 mg/kg/three days) and followed for 28 days. Blood levels of chloroquine and desethylchloroquine were measured on day 2 and on the day of reappearance of parasitemia. The cumulative incidence of treatment failure was calculated using the Kaplan and Meier survival analysis.

RESULTS:

The mean parasitemias (asexual) on day 0 were 6,147 parasites/μl of blood in the Riberalta population, 4,251 in Guayaramerín and 5,214 in Yacuiba. The average blood concentrations of chloroquine-desethylchloroquine during day 2 were 783, 817, and 815 ng/ml, respectively. No treatment failures were observed in Yacuiba, whereas in Riberalta and Guayaramerín, the frequencies of treatment failures were 6.2% and 10%. Blood levels of chloroquine and desethylchloroquine in patients with treatment failure showed values below 70 ng/ml on the day of reappearance of parasitemia.

CONCLUSION:

Resistance of Plasmodium vivax to chloroquine was not demonstrated in three regions of Bolivia.

• Authors: Arletta Añez, Dennis Navarro-Costa, Omar Yucra, Cecilia Garnica, Viviana Melgar, Manuel Moscoso, Ricardo Arteaga, Gladys Nakao
• Journal: Biomedica : revista del Instituto Nacional de Salud (Biomedica) 2012 Oct-Dec Vol. 32 Issue 4 Pg. 527-35 ISSN: 2590-7379 [Electronic] Colombia
• Vernacular Title: Respuesta terapéutica de Plasmodium vivax a la cloroquina, en Riberalta, Guayaramerín y Yacuiba, Bolivia.
• PMID: 23715228 (Publication Type: Comparative Study, Journal Article, Multicenter Study, Research Support, Non-U.S. Gov't, Research Support, U.S. Gov't, Non-P.H.S.)

Chemical References

• Antimalarials
• Chloroquine
• desethylchloroquine

Topics

• Adolescent
• Adult
• Animals
• Antimalarials (blood, therapeutic use)
• Bolivia (epidemiology)
• Child
• Child, Preschool
• Chloroquine (analogs & derivatives, blood, therapeutic use)
• Drug Resistance
• Female
• Humans
• Malaria, Vivax (drug therapy, epidemiology, parasitology)
• Male
• Middle Aged
• Parasite Load
• Parasitemia (drug therapy, epidemiology, parasitology)
• Plasmodium vivax (drug effects)
• Pregnancy
• Pregnancy Complications, Infectious (drug therapy, epidemiology, parasitology)
• Rural Population
• Young Adult