[Update on immunohistological classification of amyloidoses].

The exact classification of amyloid in surgical pathology specimens is complicated by the increasing number of amyloid diseases, with more than 25 different currently known amyloid proteins. Special attention has to be paid to distinguishing hereditary amyloidosis from AL amyloidosis. For this reason we started several years ago to search specifically for hereditary amyloidoses by improving the immunohistochemical classification of amyloid with new antibodies and by applying molecular biology. Since then we have found various cases of systemic and local amyloid diseases in Germany, including, AApoAI-, AFib-, AKer-, ALys- and ATTR-amyloidosis, as well as hitherto unknown amyloidoses. Based on an increasing number of referrals we also collected substantial numbers of cases, which allowed a direct comparison of the prevalences of the various amyloid diseases in organ biopsies.