Role of Calretinin Immunohistochemical Stain in Evaluation of Hirschsprung’s Disease

Abstract

Introduction: Hirschsprung’s Disease (HD) is a common congenital disorder characterised by absence of enteric neurons along a variable length of large bowel involving a segment of the rectum and the adjacent proximal bowel. The definitive diagnosis is based on histopathological study of rectal seromuscular biopsies. Calretinin Immunohistochemistry (IHC) staining adds to the diagnostic yield as it allows better appreciation of the mature and immature ganglion cells including the segments with paucity of ganglion cells. Aim: To assess the usefulness of calretinin IHC in the diagnosis of HD as an add-on technique to routine Haematoxylin and Eosin staining. Materials and Methods: This was a prospective study carried out in the Department of Pathology, SCB Medical College, Cuttack during the period from August 2016 to July 2018. Full thickness rectal biopsy specimens were processed and subjected to routine Hematoxylin and Eosin Stain (H&E) staining and Calretinin IHC staining. A thorough search of ganglion cells was made in both types of stained slides. The observations were tabulated and compared for diagnostic accuracy. Statistical analysis was done using Statistical Packages for Social Sciences (SPSS) Inc, Chicago IL version 15.0 windows. Through, ANOVA and Chi-square test. Results: Calretinin IHC provided superior diagnostic yield compared to routine H&E staining. A total number of 45 cases were studied. Sensitivity of 95.4% and specificity of 55.5% were obtained. It also presented higher accuracy values, than H&E (p=0.49). Conclusion: Calretinin is a superior immunohistochemical staining method that serves as a reliable additional diagnostic tool for better morphological appreciation of ganglion cells and thereby helps in establishing the diagnosis of HD.