胃生検が確定診断の糸口になった原発性全身性アミロイドージスの1例

Primary Systemic Amyloidosis Diagnosed by Stomach Biopsy, Report of a Case

　アミロイドージスは原因不明の代謝異常によりアミロイドが金身性に沈着する疾患で，従来剖検による報告例が多く，生前の診断は困難とされていたが，最近は肝，腎，消化管などの生検によって生前にその確定診断の得られる症例が漸次増加している¹⁾．

　われわれは今回，胃X線，内視鏡検査にて異常所見を認め生検によりアミロイド沈着を証明し，引き続き肝，腎，腸管生検にて同様の所見を得て，原発性全身性アミロイドージスと診断できた1例を経験したので報告する．

　This report of a case shows how a stomach biopsy became a clue to a definite diagnosis of primary systemic amyloidosis.

　The patient was a 48 years-old male with chief complaints of epigastralgia and a sense of fullness at the gastric region. An endoscopical biopsy specimen from the gastric mucosa showed deposits of eosinophilic amorphous substance in the lamina propria mucosae. The amorphous substance was revealed as amyloid by congo-red staining, PAS reaction and by polarization microscope after congo-red staining. Subsequent biopsies from the esophagus, the small intestine, the colon, the liver and the kidney revealed deposits of the same substance, amyloid, in each organ.

　There was no other disease found as the secondary systemic amyloidosis. With this finding and on the basis of the distribution pattern of amyloid-deposits, the final diagnosis was primary systemic amyloidosis.

　X-ray examination revealed irregular, rough grandular, small nodular mucosal pattern, and sporadic small barium flecks were observed mainly all around the body of the stomach. However, mobility of the gastric wall was kept well and flow out of barium was rapid.

　Endoscopic examination also revealed irregular, coarse mucosal surface, and multiple pin-point red spots or small hemorrhage around the upper to middle parts of the body.

　Laboratory examination showed long-term persistent proteinuria, but Bence-Jones protein was negative in the urine. Elevation of the blood level of BUN and creatinine value, and decrease of PSP-value suggested impairment of renal function. There was no hypertension. Elevation of immunogloblin level (ⅠgG, ⅠgA) was found. It is said that histological examination of biopsy specimen is a useful and the only one way to make a definite preoperative diagnosis of systemic amyloidosis. Therefore, rectal biopsy is also emphasized. Furthermore, incidence of stomach involvement of the amyloidosis was not lower than that of the rectum.

　With the recent development of instruments and techniques for detailed examination of the upper G-Ⅰ tract, combination of x-ray, endoscopic and biopsyexaminations can lead to an earlier and more definite diagnosis of systemic amyloidosis than in the past.