分類困難な小腸潰瘍・びらんの現状

Actual Status of Unclassified Small Intestinal Ulcerative Lesions

要旨　本邦において，原因不明消化管出血に対してカプセル内視鏡を施行した場合，およそ30％の対象に潰瘍性病変が指摘される．NSAIDsを服用している場合においてはNSAIDs起因性と診断されることが多いが，正確な診断は簡単ではない．さらに，健常者においても10％程度は無症候性の小腸潰瘍性病変を有しており，原因疾患の診断は困難を極めている．近年，腸内細菌叢が小腸潰瘍性病変に深く関与している可能性が指摘されており，今後の解明が望まれている．

　In Japan, small intestinal ulcerative lesions are detected by capsule endoscopy in approximately 30％ of patients presenting with obscure gastrointestinal bleeding. Among patients taking NSAIDs（nonsteroidal anti-inflammatory drugs）, those with small intestinal ulcerative lesions are often diagnosed with NSAID-induced small intestinal ulcers. However, this diagnosis is difficult ; therefore, several patients may be misdiagnosed. Furthermore, diagnosis of these lesions is complicated because approximately 10％ of healthy subjects have small intestinal ulcerative lesions. Recently, several studies have reported that small intestinal bacterial flora is profoundly associated with the incidence of small intestinal ulcerative lesions. Hence, future resolution of this issue is required.