CURRENT CONCEPTS IN PATHOLOGICAL DIAGNOSES - PARASITIC DISEASES

Recovery and identification of protozoan and metazoan parasites in tis sues requires familiarity with parasite anatomy and life-cycles and ac cess to the specialized literature available on this topic. Certain sp ecies of parasitic protozoa are being seen more commonly, especially i n the immunocompromised host, whereas most helminths and arthropods ar e seen less frequently. A systematic approach to the evaluation of for eign bodies in tissues is particularly helpful to arrive at correct di agnoses and avoid misidentification of the numerous objects which may resemble parasites. In this paper we review some of the basic morpholo gic characteristics that can be used to differentiate the major groups of human parasites in histologic sections, and discuss optimal handli ng and histochemical staining of tissues suspected to contain a parasi te.