Anorectal Electromanometrical Patterns in Children with Isolated Neuronal Intestinal Dysplasia

Abstract

The aim of this study was to report our new findings on anorectal electromanometrical patterns in patients with isolated neuronal intestinal dysplasia (IND) type B. We reviewed and analyzed the records of preoperative anorectal electromanometric examinations in 17 patients (10 male and 7 female) with IND. The diagnosis of IND was made based on a pathological examination. Mean age of the patients was 6.3 years (range 4 months to 16 years). In the preoperative barium enema study, a narrowed distal segment with proximal dilatation was noted in 8 patients, dilatation of the sigmoid or rectum without a narrowed distal segment was observed in 4 patients, and no specific findings were found in 5 patients. Out of 17 patients, only 5 patients showed positive staining for AChE in the rectal suction specimens. The electromanometric examination showed no significant difference in anal resting pressure and the length of the high pressure zone between the IND and the functional constipation (FC) groups. The frequency of anal peristalsis in the IND group, however, was significantly lower than that in the FC group. Sixteen IND patients showed an internal relaxation. However, the threshold value to evoke the relaxation in the IND group was significantly higher than that in the FC group. Moreover, the latent period of reflex and the duration of a relaxation in the IND group were longer than those in the FC group. Finally, two specific shapes of reflex wave ("W" or "U" shape) were observed in 10 patients with isolated IND type B, while no such shapes were noted in the FC group. These new findings support the notion that anorectal electromanometry is a safe and useful screening examination for IND patients.