[Conventional histological diagnostics in coloproctology].

With the introduction of immunohistochemical methods, histopathological diagnosis based on formalin fixed, paraffin embedded tissue in coloproctology has substantially improved. In recent years, the routine use of immunohistochemistry for S100, cathepsin D and a picrosirius red staining has proven to be sufficient for the diagnosis of hypoganglionosis of the myenteric plexus and desmosis of the muscularis propria. In some cases, an immunohistochemical reaction for CD 117 is also necessary for the evaluation of Cajal cells. In contrast, in ultrashort Hirschsprung's disease, aganglionosis of the anal ring, aganglionosis of the musculus corrugator cutis ani, and internal sphincter, the histochemical acetylcholinesterase reaction is essential and not replaceable by any immunohistochemical method.Immunohistochemistry, classical histological stains and enzyme histochemistry are complementary histopathological techniques. In contrast to immunohistochemistry, enzyme histochemistry requires native cryostat sections for the assessment of enzyme activity. As a consequence, biopsy performance and transport to pathology departments should be particularly well organized.