Passive gravitational sedimentation of peripheral blood increases the sensitivity of microscopic detection of malaria

Abstract

ObjectiveTo determine if passive gravitational sedimentation of blood samples, followed by buffy coat thin smear preparation could increase the sensitivity of malaria diagnosis when compared to conventional thin smear preparation without the additional cost of centrifuges or molecular diagnostics. MethodsBlood samples were collected from 205 patients. Each patient sample was analyzed using all three methods of sample preparation. ResultsBuffy coat analysis of centrifuged blood samples greatly increased the sensitivity of malaria diagnosis when compared to standard thin smear techniques. Sensitivity between mechanically centrifuged samples and gravitationally sedimented samples showed equal improvement in sensitivity when compared to standard thin smear preparation. ConclusionsPassive gravitational sedimentation of red blood cells followed by buffy coat analysis dramatically improves the sensitivity of malaria diagnosis without the additional costs associated with centrifugation.