Differential staining of schistosome ova in biopsies

ABSTRACT

The significance of identifying the infecting schistosome species has been high lighted recently by the availability of specific chemotherapeutic agents and an awareness that the tissue response - and therefore the prognosis - may be species-dependent. Moreover human interference with the ecological systems in parts of the developing world has modified the epidemiological map of schistosomiasis resulting in a rising incidence of mixd infections. Differentiation between the ova of Schistosoma mansoni and S. haematobium the two species commonly seen in immigrants to Kuwait and to other non-endemic areas of the world, usually poses no problems in urinary and faecal specimens. However, in histopathological samples, their distinctive morphological features cannot often be assessed reliably. We obtained satisfactory differentiation by using a modified Ziehl-Neelsen method on 81 routinely fixed and processed biopsy samples. Moreover, on destained sections previously stained with haematoxylin and eosin, the differences were equally evident. Details of the method and its applications both in routine histopathological practice and for research arc discussed