2)慢性関節リウマチ

Gastrointestinal Lesions in Rheumatoid Arthritis

　慢性関節リウマチ(RA)では，治療薬(主に非ステロイド性抗炎症剤 ; NSAIDs)，続発性アミロイド－シス(ア症)，血管炎などによる消化管病変を生じることが知られている．NSAIDsでは主に胃粘膜障害(潰瘍)を生じるが，通常の潰瘍と異なり無症状のことが多く幽門前庭部に好発し，浮腫の強い多発性や下掘れのものが多い．ア症の臨床像は，他疾患に合併するア症と同様であるがRAの予後を左右する重篤な合併症であり，早期診断のためには十二指腸生検が有用である．また，RAによる腸病変ではNSAIDsや血管炎などによる虚血が関与しているものと推測されるが，その消化管病変は極めて多彩であり，原因別にみても多くの共通点があるため，その発症にはこれらの要因が互いに関連しあいRAの腸病変を形成しているものと推測される．

　Rheumatoid Arthritis (RA) is known to give rise to various types of gastrointestinal complications such as those due to vasculitis, secondary amyloidosis, therapeutic drugs including nonsteroidal antiinflammatory drugs (NSAIDs), and so on. NSAIDs cause mainly gastric mucosal injury (ulcer). Unlike usual ulcers, these ulcers are often asymptomatic, predominant in the antrum, multiple, deep and accompanied with edema. Amyloidosis is a serious complication affecting the prognosis of patients of RA. Its clinical features are similar to amyloidosis accompanying other diseases. Biopsy from duodenal mucosa is useful for early diagnosis of amyloidosis. Intestinal lesions in RA are thought to be involved in ischemia such as that induced by vasculitis, NSAIDs, and others. These intestinal lesions show an extremely wide variety, and the causes have many points in common with each other. Therefore, it is speculated that intestinal lesions in RA might be formed as a result of a correlation of these factors, i. e. vasculits, drugs, etc.