電解質異常を来した巨大な直腸villous tumorの1例

Giant Rectal Villous Adenoma with Electrolyte Imbalance, Report of a Case

要旨　患者は72歳の男性で，主訴は慢性下痢，腹痛，倦怠感．1978年ごろより時々下痢があり放置．1981年，風邪を引いてから急に主訴が出現し，著明になったため入院した．初診時は1日十数回の粘液透明の下痢があり，多いときは2,300mlにも達した．著明な脱水，高窒素血症があり，電解質失調を来していた．水様便中のカリウム濃度が血清中より5倍も多い点が注目された．注腸造影では直腸よりS状結腸にかけてけば立ち像があり，二重造影像が不明瞭であった．内視鏡では8～25cmの大腸にビロードを敷き詰めたような平坦な腫瘍があり，多量の粘液に覆われていた．villous adenoma with severe fluid depletionの診断にて，1カ月間で電解質を補正後，前方切除術を施行した．術後経過は良好で，電解質異常，下痢も消失し，現在も健在である．腫瘍の大きさは20×14cm，tubulo-villous adenomaで癌の合併はなかった．本邦における本症の報告は6例あったが，本例がその典型例と思われる．

　A rectal wide-spread grown villous adenoma in a 72 year-old carpenter with electrolyte depletion syndrome is reported. He was admitted to our hospital in April, 1981 complaining of intermittent diarrhea, general malaise during past two years. Gradually, he started to experience nausea, vomiting and abdominal pain with transparent abundant watery mucus stool like urine during the past three months.

　On admission, he suffered from diarrhea ten times or more, of a maximum amount of 2,300 ml per day, but he had an entirely clear consciousness. Clinical examination showed a great amount of dehydration and hyperazothemia. Particularly, electrolyte imbalance was noted at Na 127, K 2.83, Cl 70 mEq/l and waterry stool contained five times the concentration of potassium compared with serum one. Barium enema study revealed vague double contrast film with shaggy nap features on the upper rectum extending to the sigmoid colon. Endoscopic study showed slight reddish yellow velvety mucosa, 8-24 cm from anal verge, filled with copious transparent mucus. He underwent anterior resection after fluid and electrolyte replacement, and postoperatively, diarrhea ceased.

　Resected specimen showed rectal villous adenoma measuring 20×14 cm and occupying the circumference of the large bowel, and broad-base, cerebral gyrus appearance, velvet like touch and clearly defined border from normal mucosa were characteristic. Histological finding showed tubulo-villous adenoma without carcinoma.

　Villous adenoma with electrolyte depletion syndrome is rare in Japan. Only six cases have been reported and this case is a typical example of one.