Comparing Leishman and Giemsa staining for the assessment of peripheral blood smear preparations in a malaria-endemic region in India.

Background: Microscopy of peripheral blood thin and thick films remains the reference for malaria diagnosis. Although Giemsa staining is most commonly used, the Leishman staining method provides better visualization of the nuclear chromatin pattern of cells. It is less well known whether accuracy of parasitaemia assessment is equally accurate with the latter method.

Methods: Peripheral blood thin and thick smears from consecutive febrile patients admitted to Ispat General hospital, Rourkela, Odhisa, India, were stained with Giemsa and Leishman stain. Methods were compared for species identification, parasite quantification, and ability for identification of alternative diagnoses.

Results: Blood films from 1,180 fever patients were compared according to staining method, of which 111 were identified as parasitaemic using Giemsa and 110 with Leishman staining. The Kappa value as a measure of agreement between methods was 0.995 (p < 0.001), and the log10parasitaemia between methods were strongly correlated (r2 = 0.9981). In parasite negative patients, thin smear assessment contributed to making a diagnosis in 276/1,180 (23%) of cases. These assessments were better made in Leishman-stained preparations, especially for the assessment of morphological changes in red and white cells.

Conclusion: Leishman's staining method for thin and thick smears is a good alternative to Giemsa's stain for identifying Plasmodium parasites. The Leishman method is superior for visualization of red and white blood cell morphology.