症例は70歳代男性.周期性血小板減少症に対して当院血液内科で加療中であり,血小板数は約1ヵ月で5~30×10^4/μlの間を推移していた.2008年に血小板減少期に一致して黒色便を認めたため,上部・下部消化管内視鏡検査を施行したが出血源の同定には至らなかった.カプセル内視鏡検査では,小腸にびらんや潰瘍,出血を疑う所見を認めており,アスピリンによる薬剤関連性小腸粘膜障害が疑われた.レバミピド300mg/日とイルソグラジンマレイン酸塩4mg/日を投与開始し,約1ヵ月に1回の血小板減少期に合わせて,食事を半消化態栄養に変えることにより,約1年間貧血の進行を認めなかった.しかし,2012年に大量の黒色便を認めたため,濃厚赤血球製剤および濃厚血小板製剤の投与が必要となり,循環器内科と相談の上,アスピリンを中止しサルポグレラート塩酸塩のみ継続することとした.その後は貧血の進行を認めずに経過している.周期性血小板減少症は非常に稀な疾患であり,根治的治療法が明らかとなっておらず,薬剤関連性小腸粘膜障害に伴う消化管出血への対応に難渋した.
The patient was a 70-year-old man undergoing medical treatment in our hospital hematology department for cyclic thrombocytopenia whose platelet count had hovered between 5~30×10^4/μl for about 1 month. Because he was found to have black stools during the same period as the thrombocytopenia in 2008, he underwent upper and lower gastrointestinal endoscopy, but the source of bleeding could not be identified. Capsule endoscopy showed findings suspicious of ulcer or erosion with bleeding, and drug-related damage to the small intestinal mucosa caused by aspirin was suspected. Administration of irsogladine maleate 4 mg/day and rebamipide 300 mg/day was begun, and then by changing to a low-residue diet to match the cyclic phase of the thrombocytopenia of about once per month, no progression of the anemia was seen for about 1 year. However, since he was admitted to our hospital immediately after he experienced a large amount of bloody bowel discharge, administration of packed red blood cell preparation and platelet concentrates was required, and in consultation with the Department of Cardiology, we stopped the aspirin and continued to administer only sarpogrelate hydrochloride. There has been no further progression of the anemia. Cyclic thrombocytopenia is a very rare disease, and a curative treatment is unclear. Therefore, it was difficult to respond to gastrointestinal bleeding associated with drug-related damage of the small intestinal mucosa.