The vivax malaria is a disease that effects around 40% of the world, to treat it,
chloroquine (150 mg) and primaquine (15 mg). This is an 8-aminoquinoline with
tissue schizonticide action. Among the adverse effects enhance the capacity to
hemoglobin oxidation, dose-dependent, which is exacerbated in individuals with
glucose-6-phosphate dehydrogenase deficiency. When considering the lack of
studies concerning the methemoglobin levels and its correlation with primaquine
concentrations plasma in patients with vivax malaria, is justified this study using as
tools to monitor the plasma primaquine concentrations and its correlation with
methemoglobin levels. In this sense, it was followed up clinically and laboratory
findings of 20 patients with vivax malaria before (D0) and after three (D3), seven (D7)
and fourteen (D14) days starting the treatment, as well as validation of the method
for primaquine determination by high performance liquid chromatography (HPLC).
Methemoglobinemia was evaluated using the method of Hegesh et al. (1970) and
glucose-6-phosphate dehydrogenase by colorimetric method of Brewer et al. (1962 ).
The methodology validated was demonstrated efficient for primaquine determination,
whose average levels at D3, D7 and D14 were 227 ± 106 ng / mL, 191 ± 97 ng / mL
and 160 ± 128 ng/mL. In the analysis according to gender was not observed
differences significant in the drug levels in several days of study. The average
methemoglobin levels in D0, D3, D7 and D14 were 1.15 ± 0.9%, 4.1 ± 2%, 5.7 ± 2%
and 3 ± 1.4%, respectively. There was an increase in the methemoglobin level after
drug administration, without difference by gender. There was not significant
correlation between the methemoglobin levels and primaquine concentrations
plasma in both sexes. The coefficients of Pearson correlation for males and females
were 0.8296 and 0.8137, respectively. We observed impaired expression of the
enzyme glucose-6-phosphate dehydrogenase in six male patients without differences
between the methemoglobin levels and primaquine concentrations plasma,
compared with patients with expression normal of the enzyme.
|
