進行性全身性硬化症（PSS）の消化管病変―小腸病変を中心に

Gastrointestinal Manifestations in Patients with Progressive Systemic Sclerosis: Measurements on Small Intestinal Radiograph

要旨　進行性全身性硬化症（PSS）患者12例を対象とし，消化管病変の特徴を小腸を中心に検討した．X線所見では食道・十二指腸・空腸の拡張を各6例（50％）に，大腸のhaustraの消失・減少を5例（46％）に認めた．充満像および二重造影像の検討では，空腸拡張像を認めたPSS群は正常対照群と比べ腸管幅が有意に大きく皺襞谷幅が有意に小さかったが，皺襞山幅には差がなかった．PSS症例の充満像と二重造影像を比較すると，二重造影像において腸管幅は更に拡張し，皺襞谷幅は更に縮小した．小腸X線像の経過が追えたPSS例では，経過と共に腸管幅の拡大と，皺襞谷幅・山幅の縮小が観察された．生前腸管の拡張が著明であった剖検例の組織像では，全消化管の粘膜下層・固有筋層に膠原線維の沈着と慢性炎症細胞浸潤を認めた．筋線維の消失・減少は，特に十二指腸・空腸の内輪筋において顕著であった．以上の結果から，PSS患者の小腸X線像では腸管幅の拡張と皺襞谷幅の縮小に注目することが診断上重要である．更に，拡張の程度は腸管の組織障害の程度を反映していると考えられ，病変の進行度を客観的に評価するうえで，小腸X線検査は有用であると思われた．

　Twelve patients with progressive systemic sclerosis (PSS) were reviewed to study the characteristic features of gastrointestinal involvement, especially of the small intestine. The examinations included single-contrast or double-contrast radiography and endoscopy of the esophagus, stomach, duodenum, small intestine, and colon.

　Dilatation of the esophagus, duodenum and jejunum was detected by barium meal study in half of the twelve patients, whereas the stomach was not radiographically or endoscopically affected in any patient. Barium enema examination revealed diminution or disappearance of colonic haustration in five out of eleven patients studied. In patients with PSS, the caliber of the jejunal lumen was larger and the intervalvular distance was smaller than that in normal controls respectively, while the valvular width was not significantly different between the PSS and control groups. In addition, double-contrast study of the small intestine was more useful than barium meal study to detect dilated caliber of the jejunal lumen and shortened intervalvular distance. In five patients, follow-up small intestinal examinations demonstrated the progression of the dilatation of the jejunal caliber, the shortening of intervalvular distance, and the increase in valvular width. Histological examination of the autopsy specimen in one patient, whose esophgeal and small intestinal dilatation had been confirmed while alive, revealed loss or disappearance of the muscular layer, accompanied by deposition of the collagen fibers and submucosal infiltration of mononuclear cells throughout the alimentary tract. In addition, the proper muscle, especially the inner circular layer, of the duodenum and the jejunum was more severely affected.

　These results suggest that PSS affects the small intestine more frequently than previously described, and also that the jejunal dilatation with the shortened intervalvular distance on radiograph is a diagnotic finding for PSS.