[Histopathological and immunohistochemical studies of generalized amyloidosis].

Histopathological and immunohistochemical studies were performed on 10 autopsy cases of generalized amyloidosis. The results showed that there were 3 cases of secondary amyloidosis (AA protein), 4 cases of primary amyloidosis (AL protein) and 3 cases of amyloidosis associated with multiple myeloma (AL protein); no familial amyloidosis (AF protein) was identified. Amyloid substances detected in all of the cases were similar in appearance morphologically, and differentiation of different types of amyloid proteins could not be depended on whether the disease is primary in nature or there is amyloid deposition in various organs or tissues. Anyhow, the differentiation could be made by pre-treatment with KMnO4 in Congo red stain or by immunoperoxidase stain, and the latter one is considered to be more reliable in identifying amyloid protein types.