Assessment of Matrix Metalloprotease - 7 (MMP7) Immunohistochemistry in Biliary Atresia and Other Pediatric Cholestatic Liver Diseases.

Background and aims: Biliary atresia (BA) is a progressive fibro-obliterative cholangiopathy. The histopathological diagnosis is often challenging and an immunohistochemical marker is often sought as an adjunct. We evaluated MMP7 immunohistochemistry in BA and other non-BA pediatric cholestatic liver diseases. Materials and methods: MMP7 immunohistochemistry was applied in 5 age-matched normal control, 23 cases of BA and 43 cases of non-BA pediatric cholestasis including 16 cases of choledochal cyst (CC), and a multiplication score was obtained by multiplying the intensity and percentage positivity in the cholangiocytes. Results: BA showed a high mean MMP7 multiplication score which was significantly different from the normal control and other non-BA pediatric cholestatic diseases including CC ( p value < 0.001). The sensitivity, specificity, positive, and negative predictive values of MMP7 immunohistochemistry were 91.3%, 93.02%, 87.5%, and 95.2% respectively. Conclusion: MMP7 immunohistochemistry may be an adjunct to histomorphology in BA.