Comparative study of peripheral blood smear, quantitative buffy coat and modified centrifuged blood smear in malaria diagnosis.

ABSTRACT

The present study was aimed at modifying the centrifuged blood smear (modified centrifuged blood smear or MCBS), to make it a feasible and standardized procedure. The results obtained were compared with the current diagnostic methods - peripheral blood smear (PBS) and quantitative buffy coat (QBC). Blood samples collected from 100 suspected malaria patients were subjected to all three tests. It was found that PBS had 86.79% sensitivity and was absolutely specific. QBC was 96.22% sensitive and 93.61% specific. The majority of variations occurred in PBS negative cases; cases with parasite count Plasmodium falciparum. It was seen that by the addition of centrifugation to the conventional smear technique (MCBS) improved its sensitivity from 86.79% to near 100%. QBC and MCBS were found superior to PBS. Since MCBS combines principles of both QBC and PBS, it is as sensitive as QBC, as specific as PBS, and above all, easily performed and affordable.