The small bowel diseases detected by capsule endoscopy in patients with chronic abdominal pain: A retrospective study

Chronic abdominal pain (CAP) remains a particular challenge because of its complicated causes, especially when the disorders involve the small bowel, where it is quite difficult to intubate the flexible endoscopes. This study was to investigate the small bowel diseases detected by capsule endoscopy (CE) in CAP patients to evaluate the role of CE on CAP, and analyzed the relationship among the clinical characteristics of CAP patients and the positive rates of CE findings to search for the indications of CE for CAP patients. This retrospective study included 341 patients with CAP defined as recurrent abdominal pain for no <3 months. Each patient underwent CE after a negative diagnostic work-up. All CE images were reviewed by 3 gastroenterologists independently. The positive findings were defined as abnormal findings in the small bowel that might have been the causes of CAP. The final diagnosis was confirmed by CE findings, clinical features, histopathology, and a response to the treatment during the follow-up for at least 3 months after CE. The overall positive rate of CE findings was 28.15% (96/341). The positive rate in CAP-A (CAP with associated symptoms) group was significantly higher than that in CAP-O (CAP only) group (33.16% vs 21.38%, P = .017). Multivariate logistic regression analysis revealed that weight loss (odds ratio [OR] = 2.827, 95% confidence interval (CI) = 1.938–4.926), hypoalbuminemia (OR = 6.142, 95%IC = 4.129–8.274), elevated erythrocyte sedimentation rate (ESR) (OR = 4.025, 95%IC = 3.178–6.892), or increased C-reactive protein (CRP) (OR = 7.539, 95%CI = 5.365–11.723) were significantly associated with high positive rates. On follow-up, final diagnosis was confirmed in 56 of 69 (81.16%) patients with positive CE findings. About half of these patients (46.38%, 32/69) were diagnosed as inflammatory diseases, including Crohn disease (12), tuberculosis (5), NSAID enteropathy (4), etc. Tumors were proved in 21.74% (15/69) patients, including malignant in 7 cases and benign in 8 cases. Parasitosis was found in 9 (13.04%) patients. This study suggests that CE may be helpful for CAP patients to detect the small bowel diseases, half of which were comprised of inflammatory diseases. Besides, weight loss, hypoalbuminemia, elevated ESR, or increased CRP may be regarded as the indications of CE for CAP patients.