The effects of pyrimethamine and sulphadoxine mixture on plasma haemoglobin/methaemoglobin ratio of Hbaa erythrocytes

Abstract

Fifty(50) blood samples of human red blood cell genotype HbAA were assayed in-vitro to determine the effect of increasing combined concentrations of pyrime- thamine and sulphadoxine (ratio 20:1w/w) solution on plasma levels of hemoglobin (Fe 2+)/methaemoglobin (Fe 3+) ratio. The concentrations used were 0.2, 0.4, 0.6, and 0.8%. The mean percentage plasma hemoglobin level of the control sample was 97.86 ± 0.74%, while the test samples at 0.2, 0.4, 0.6 and 0.8% concentrations showed hemoglobin levels of 96.52 ± 0.75, 96.72 ± 0.64, 97.42 ± 0.61 and 96.07 ± 1.49% respectively. The mean percentage methaemoglobin level of the control sample was 2.14 ± 0.74%, while the test samples at 0.2, 0.4, 0.6 and 0.8% concentration gave plasma methaemoglobin levels of 3.48 ± 0.75, 3.28 ± 0.64, 2.55 ± 0.61 and 3.93 ± 1.49% respectively. These result showed a concentration dependent variability with the percentage of pyrimethamine/sulphadoxine mixture that was added to the test samples. Statistical analysis showed a significant difference between the mean values of the control and test samples (p<0.05) for both plasma hemoglobin and methaemoglobin levels. Furthermore, a comparative evaluation of plasma Fe 2+/Fe 3+ ratio indicated a relative elevation of plasma methaemoglobin levels. The values were: 46:1 (control), 28:1(0.2%), 29:1(0.4%), 38:1(0.6%) and 24:1(0.8%). These findings suggest that the combined concentrations of pyrimethamine and sulphadoxine has a propensity to elevate plasma methaemoglobin levels in a concentration depended manner.


IJONAS Vol. 3 (1) 2007: pp. 116-121