A Comparison of Rectal Suction and Full Wall Biopsy in Hirschsprung’s Disease

Abstract

Introduction: Hirschsprung’s disease (HD) is defined as congenital agangliosis of the colon wall from the rectum extending cranially. There are several radiologic methods for screening for HD but it is a biopsy of the colon wall that confirms the diagnosis. Initially the full wall (FW) biopsy was the method of choice. FW biopsy requires general anaesthesia and creates a full wall laceration of the colon wall. The newer method called rectal suction (RS) biopsy is carried out by means of a catheter inserted into the rectum that blindly cuts a biopsy including mucosa and submucosa. It can be performed bedside. If ganglion cells are seen in the biopsy specimen, HD can be excluded. The question that arises is: Can we safely move on from FW biopsy to RS biopsy without compromising diagnostic accuracy? Method and Material: Our study is a retrospective revision of 20 FW biopsies that were supplemented with RS biopsies. RS biopsies with insufficient submucosa were excluded. The RS biopsies were assessed by a senior pathologist in a double blind fashion and the result was compared with FW biopsies. FW biopsy was considered gold standard. Results: The exact binominal test for the non-inferiority test of congruence of RS biopsy with FW biopsy as gold standard was not statistically significant using an inferiority margin of 80% (p = 0.06918) [H0: p_RS ≥ 0.8]. The estimated probability for a successful RS biopsy was 95% and the one-sided 95%-confidence interval associated with the test was 0.784 to 1.00. Conclusion: Our results indicate that we can move on from FW biopsy to RS biopsy without compromising the diagnostic value of the rectal biopsy in a clinically significant way. A prospective study to confirm our results would be of great value.