Histochemistry in the diagnosis of non-neoplastic gastrointestinal disorders

The alimentary tract serves as host to a large number of diseases. In the non-neoplastic group of disorders, conventional histochemistry continues to play an important diagnostic role. It is particularly important in recognizing specific infectious diseases, such as Helicobacter gastritis, Whipple disease, intestinal tuberculosis and other forms of mycobacteriosis, malakoplakia, intestinal spirochetosis, fungal enteritides, amebiasis, cryptosporidiosis, isosporiasis, and microsporidiosis. Those conditions and their histochemical properties are discussed in this review, along with the use of histochemistry in the characterization of structural gastrointestinal disorders. The latter include mucosal metaplasias, amyloidosis, glycogenic acanthosis of the esophagus, lymphocytic-collagenous colitis, gastric neuroendocrine hyperplasia, and pill gastritis.