Reliability of S-100 and Tuj-1 immunofluorescence markers in the diagnosis of Hirschsprung’s disease

Background: Hirschsprung’s disease (HSD) is a congenital malformation of the hindgut characterised by absence of intrinsic ganglion cells. Acetyl cholinesterase (AChE) staining is used as a gold standard test in HSD. Intramucosal neuroglial cells (INCs) are present in aganglionic colonic mucosa of HSD patients, challenging our current understanding.Objectives: To evaluate for the presence of INCs using S100 and Tuj 1 and to evaluate for the presence of ganglion cells (GCs) using Tuj1 immunofluorescence in clinically suspected cases of HSD.Materials and Methods: This study was carried out in the Department of Pathology, Bangalore Medical College and Research Institute, Bangalore on 35 colorectal biopsies of patients suspicious of HSD. Direct immunofluorescence (DIF) was done on rectal biopsies using Tuj1 and S100 markers.Results: Out of 35 biopsies, 24 showed absence of Tuj 1 and S 100 expressing cells in the biopsy and were diagnosed as HSD and 8 cases showed presence of Tuj 1 and S 100 expressing cells in the biopsy and were diagnosed as not suggestive of HSD. 3 were excluded as they were low rectal biopsies. Tuj 1 and S 100 DIF showed sensitivity of 100% and specificity of 72.7%.Conclusion: DIF markers Tuj 1 and S 100 were found to be more sensitive than AChE stain and these markers are helpful in detecting false negative cases missed by AChE. A larger cohort is necessary to consider these DIF markers as an additional tool in evaluatingand ruling out HSD in cases where AChE stain is equivocal