アミロイドA鎖型を示した膀胱アミロイドーシス

PRIMARY LOCALIZED AMYLOIDOSIS OF BLADDER WITH AMYLOID FIBRIL PROTEIN AA : A CASE REPORT

　29歳，男性．無症候性全血尿で当科初診．膀胱鏡にて，左側壁に巨大非乳頭状腫瘤を認めた．生検にてアミロイドーシスの診断のためTURおよび直腸粘膜生検を施行した．病理組織学的に，アミロイドA鎖型のアミロイドーシスであった．直腸生検，骨髄生検に異常なく基礎疾患を認めなかった．本症例は原発性限局性膀胱アミロイドーシスと診断した．

A 29-year-old male was admitted with asymptomatic total gross hematuria. Physical and laboratory findings were almost normal except for hematuria on urinalysis. Cystscopic finding showed giant nonpapillar-y bladder tumor on the left lateral wall. Urinary Bence-Jones protein was not detected. Amyloid deposits were observed histopathologically in the bladder submucosa, but not in the rectal submucosa. Amyloid deposits in KMnO₄ reaction were not stained, then amyloid fibril protein AA was showed. AA type in amyloidosis is generally known as secondary, but eleven percents in AA type amyloidosis were reported primary amyloidosis.