Pathological Review of Modified Rectal Biopsy for Diagnosis of Hirschsprung’s Disease.

Abstract

Background: The diagnosis of Hirschsprung’s disease (HD) is based on histological confirmation of the absence of normal ganglion cells in the colonic wall utilising full-thickness rectal biopsies (FRB) or suction rectal mucosal biopsies. The attendant risks in the former and cost of consumables in the later resulted in the development of a modified rectal biopsy using instruments (MRB). Reports of how this method compares to the gold standard differ in the literature. This study evaluated the adequacy of modified rectal mucosal biopsy histology in the definitive diagnosis of Hirschsprung’s disease compared to traditional biopsy techniques. Method: A histological review of 438 MRBs, and 119 Pull-through specimens and FRBs performed over an 18-year period in a single institution. Specimens were formalin fixed, paraffin processed and stained with hematoxylin & eosin. A developed set of criteria was used to assess diagnostic histological accuracy for the MRBs. Data analysis was done. Results: 321 males and 117 females with median age of 10 months were studied. 84.2% of which were diagnosed to be HD upon review of their MRBs; MRB inadequacy in 9.5%, and 6.2% had other diagnosis. Accuracy analysis was carried out on 107 patients who had both MRB and either definitive Pull-through or FRB. Sensitivity and specificity of 100% and 80% respectively, and positive and negative predictive values of 99% and 100% were derived. Conclusion: A single MRB specimen obtained by instrument can effectively diagnose Hirschsprung’s disease but requires interpretation by experienced pathologists utilising standardized reporting formats guided by best practices. This will positively impact patient management