小腸小病変に対する内視鏡所見および診断能の検討―びらん，潰瘍性病変の鑑別を中心に

Endoscopic Diagnosis for Small Lesions of the Small Intestine

要旨　小腸小病変の診断に内視鏡検査は不可欠である．しかし，その診断能や診断体系は確立されておらず，今回，当科で小腸の観察を目的としてDBEを施行した283症例を対象として検討した．283例のうち，2cm以下の小病変を有していた小病変合併例は189例（67％）であった．189例中小病変の他に主病変を合併していた症例が120例（63％），小病変のみの症例が69例（37％）だった．主病変を有する症例は，そのほとんどが確定診断に至っていた．小病変のみの症例のうち，炎症性疾患では約半数が診断未確定であった．小潰瘍性病変の検討では，2mm以下のアフタ，小びらんの診断確定率は低かった．一方，大型アフタ，びらん，小潰瘍を呈する場合は，小病変のみであってもCD，NSAIDs起因性腸炎，腸結核などの疾患に診断確定していた． CDによる小病変は縦走傾向や比較的大型のものが多く，腸結核や非特異性多発性小腸潰瘍症では典型病変に類似する傾向があった．すなわち，小病変であっても，これらの特徴を捉えることができれば診断確定に有用であると推察された．上記以外の診断が確定していない症例では，特異的な疾患による病変ではなく，広義の軽度炎症の病態としての小病変も含まれている可能性がある．こうした病変と特異的疾患を確実に鑑別診断する必要があり，今後さらなる内視鏡，X線所見を含めた小腸検査の整理，体系化が不可欠である．

　To date, small bowel diseases have been mainly diagnosed by X-ray findings. Now, endoscopic modalities for the small intestine, such as video capusle endoscopy（VCE）or balloon endoscopy, have been developed and widely used for diagnosis or treatment of small bowel diseases. Especially, as for the diagnosis of small lesions of the small intestine, endoscopic findings or biopsy are more useful than X-ray findings. Therefore, we analyzed the diagnotic yield of balloon endoscopy.

　〔Patients and Methods〕Two hundred and eighty three patients who underwent double balloon endoscopy（DBE）to observe the small intestine at our hospital were the subjects of this study. We defined lesions equal to or less than 2cm as small lesions of the small intestine in this study. In order to clarify the diagnostic yields of DBE for the small lesions of the small intestine, we investigated frequency, morphological findings and final diagnosis of the small lesions in the subjects.

　〔Results〕Among 283 cases, 189 cases（67％）were shown by endoscopy to have small lesions of the small intestine. Of these 189 cases, 120 cases（63％）had the main or typical lesions of various diseases, and 69 cases（37％）had the small lesions only. As for the former, almost all cases could be diagnosed. On the other hand, as for the later, only half of the cases of the inflammatory diseases were able to be diagnosed by DBE and other diagnostic tools. Diagnosis rate of aphthous lesions equal to or less than 2mm was low, but that of large aphthous lesions, erosions and small ulcers was high, and they were diagnosed as specific diseases such as Crohn's disease, NSAIDs induced enteritis and intestinal tuberculosis. 　〔Conclusion〕Patients who underwent DBE were frequently found to have small lesions of the small intestine. However, the diagnosis rate of cases who had only small lesions was not high and the differential diagnosis for small apthous lesion was not satisfactory. Therefore, systematization including DBE and X-ray findings for diagnosis of small lesions of the small intestine is mandatory for the forseeable future.