大動脈瘤置換術と脾摘により寛解した消費性凝固障害と特発性血小板減少性紫斑病を合併した腹部大動脈瘤の1例

Abdominal Aortic Aneurysm Associated with Idiopathic Thrombocytopenic Purpura and Consumption Coagulopathy: A case report

要旨　患者は84歳，男性．腹部大動脈瘤(AAA)および血小板減少の精査加療目的に入院した．

腹部CTでは直径約5×4.5cmの腹部動脈瘤が認められた．また，血小板1.8×10⁴/μl，フィブリノーゲンの減少，FDPの上昇を認め，消費性凝固障害を合併していた．しかし，DICに対する治療により血小板数は5×10⁴/μlまでしか増加を認めず，PA IgG高値および骨髄所見も併せて特発性血小板減少性紫斑病(ITP)が合併していると診断した．術前にγグロブリン大量療法により血小板10.0×10⁴/μlへ改善させた後，AAAに対してI型人工血管置換術とITPに対して脾摘を施行した．術中，術後とも出血の合併症なく血小板数も正常化した．ITPと消費性凝固障害を合併したAAAの症例報告はほとんどなく，術前の留意点を中心に報告した．

　A case of abdominal aortic aneurysm(AAA) associated with idiopathic thrombocytopenic purpura(ITP) and consumption coagulopathy was reported. An 84-year-old man was admitted because of AAA and thrombocytopenia(Plt1.8×10⁴/μl). Computed tomography showed an abdominal aortic aneurysm(5×4.5cm). Consumption coagulopathy was indicated by thrombocytopenia, hypofibrinogenemia and increased level of FDP. Treatment for consumption coagulopathy caused incomplete increase in platelet count. In addition, the PA IgG level was elevated and the finding of bone marrow puncture was normal, indicating complication with ITP. After the platelet count was improved from 3.7×10⁴/μl to 10.0×10⁴/μl by the preoperative treatment with γ-globulin, AAA was replaced with an I-shaped graft and splenectomy was performed for ITP at the same time. No severe hemorrhagic complication occurred during or after the operation. The platelet count was maintained at 14.0×10⁴/μl after the operation.