A histological grading system for the evaluation of co-existing NID with Hirschsprung's disease

The significance of dysplastic features in the surgical pullthrough segment of bowel in patients with Hirschsprung's disease (HD) has not yet been clarified. The aim of this study was to evaluate prospectively the ganglionated proximal bowel in 26 patients with HD (January 1988 through January 1991). The significance of dysplastic features and their influence on post operative outcome were evaluated by means of a newly devised histological scoring system based on the morphological features. Functional outcome was assessed clinically at follow-up interview. Comparison was with control specimens from 22 patients undergoing unrelated bowel surgery and a further 5 patients with neuronal intestinal dysplasia (NID). Results indicated a wide spectrum of histologically identified dysplastic features in patients with NID, the ganglionated bowel of HD and controls. Although individual abnormal features were noted in the control group, significant degrees of dysplasia were absent. The overall degree of dysplasia was less striking than that observed in NID and in the 5 patients in whom NID co-existed with HD. Dysplasia of the ENS in residual bowel could be correlated with postoperative dysfunction in 4 out of 5 patients (80%) with HD and features of co-existing NID. In addition, milder symptoms were noted in 50% of patients having a borderline score (5-6/12). This study emphasizes the relationship between clinical obstructive symptoms and a high degree of dysplasia within the ENS. A histological grading system is of value in evaluating the spectrum of abnormal findings and prospectively identifying those with functional significance in patients with NID co-existing with HD.