頸動脈ステント留置術後遅発性に生じたコレステロールクリスタル塞栓症の1例

A Case Report of Cholesterol Crystal Embolism 1 Month after Carotid Stenting

Ⅰ．はじめに

　コレステロールクリスタル塞栓症（cholesterol crystal embolism：CCE）は微細なコレステロール結晶が腎臓，皮膚，脳，眼，消化管，四肢などのさまざまな臓器の微小血管への塞栓を引き起こす全身疾患である¹⁴⁾．時として腎機能障害や血管炎，下肢閉塞性動脈硬化症，糖尿病性壊疽などと診断されることもあり¹²⁾，確立した治療指針もなく，診断・治療ともに困難な病態である^6,11,13)．線溶療法や血管内治療手技，血管外科手術などが誘因となることが多く，脳神経外科領域のCCEの報告も散見されるようになってきたが，その病態の認知度は未だ十分ではない^2,9,10)．しかしながら，脳神経血管内治療手技の普及に伴い今後より注目されるべき病態である．われわれは頸動脈ステント留置術（carotid stenting：CAS）後約1カ月を経過し発症したCCEを経験した．主にこの病態の早期診断の留意点を考察し報告する．

Cholesterol crystal embolism (CCE) is a systemic disease resulting from shedding of cholesterol crystals into the small vessels of multiple organs, including skin, kidney, gastrointestinal tract and others. Recently, neuroendovascular therapeutic procedures for athrosclerosis disease is increasing. We report a case of CCE after carotid stenting (CAS). A 73-year-old man with asymptomatic carotid stenosis was treated by percutanenous transluminal angioplasty with stenting. CAS was achieved in a short time without trouble. About 1 month after CAS, his renal function deteriorated and purpura appeared on both toe tips (blue toe syndrome) with muscle pain of the lower extremities. Under diagnosis of CCE, he was treated by Predonisolone 20mg/day and Valsartan 160mg/day, Pravastatin 10mg/day. His symptom's dramatically improved, with partial recovery of renal function. CCE rarely occurs after angiographic or interventional procedures, but is difficult to diagnose clinically and there is no established therapy. For early diagnosis of CCE strict follow-up of a patients clinical presentation and laboratory data, especially in high risk patients, is needed.