Comparison of various staining techniques in the diagnosis of Coccidian parasitosis in HIV infection

Abstract

Diarrhoea due to oppourtunistic coccidian parasites is a common clinical presentation in HIV infection. Itsmanagement differs from that of diarrhoea due to other protozoa, improvement of immune status being themainstay while specific drug treatment is available for other aetiologies, hence, the need for its accurate identification when present. This can be achieved via various diagnostic techniques, commonly microscopy inthis environment, hence the need to compare the efficacy of the commonly used stains in our locality. Theobjective of the study is to identify the most effective of the commonly used stains in identifying these parasites. Diarrhea stool samples from 250 adult HIV positives and an equal number of age and sex matchedHIV negative controls were screened, staining with trichrome, auramine and modified Ziehl Neelsen stain. Apositivity rate of 55% was reported. Modified Ziehl Neelsen, when compared with trichrome staining had81% sensitivity, 77.3% specificity, positive predictive value of 70.4%, negative predictive value of 85.9% andwhen compared to auramine staining, had 80% sensitivity, 76.7% specificity, positive predictive value of69.9%, negative predictive value of 85.2% in test subjects. There was a significant moderate level of agreement between the staining methods though trichrome showed a stronger agreement than auramine whencompared with Modified ZN in test (? value 0.569 and 0.553 respectively), and a significant, fair level ofagreement between the methods with Auramine showing a stronger agreement than trichrome when bothwere compared with Modified ZN (?value 0.399 and 0.332 respectively) in controls. Auramine and trichrome techniques are preferred for screening and diagnosis based on findings. Of these two techniques,auramine is preferred.Journal of Medical and Biomedical Sciences (2016) 5(3), 28-35Keywords:comparison, trichrome, auramine, modified ziehl neelsen, HIV