An autopsy case of multicentric Castleman's disease associated with interstitial nephritis and secondary AA amyloidosis.

It is quite rare to diagnose interstitial nephritis and secondary amyloidosis during the course of Castleman's disease (CD). To our knowledge, only four cases of interstitial nephritis and 44 cases of amyloidosis associated with CD have been reported to date. A 51-year-old man with a 9-year history of hypergammaglobulinemia was diagnosed with multicentric Castleman's disease of the plasma cell type. At the age of 55, it was complicated with interstitial nephritis, which was successfully treated with steroids and cyclophosphamide. At the age of 58, he was diagnosed with secondary AA amyloidosis and thrombocytopenia, which led to a fatal brain hemorrhage. The plasma cell type of this illness involves a relatively high incidence of amyloidosis, and the present patient suggests that some cases of multicentric Castleman's disease could proceed rapidly, be unresponsive to steroid therapy, and may have a fatal outcome.