[Amyloidoses in the Berlin Museum of Medical History of the Charité].

The Berliner Medizinhistorische Museum (Berlin Museum of Medical History) of the Charité is located in its own separate building and was officially opened in 1899. It currently houses 10,000 specimens, of which 23 were labelled with the diagnosis "amyloid" or "amyloidosis". In this retrospective study we aimed to histologically verify the diagnosis, classify the amyloid deposits immunohistochemically and correlate the type of amyloid with clinico-pathological data. The specimens were obtained between 1866 and 1987 and included 17 kidneys, five spleens and one liver. The diagnosis could be confirmed histologically using Congo red staining and polarization microscopy in 22 specimens. However, the diagnosis could not be confirmed in the oldest specimen, which had been labelled by Rudolf Virchow himself. Immunohistochemically amyloid was classified as either AA amyloidosis (19 cases) or AL amyloidosis (two cases). Tuberculosis was the most common cause of AA amyloidosis. This study shows that a surgical pathological re-evaluation of historical specimens can verify the original diagnosis. This is historically fascinating and also offers a valuable addition to student teaching.