Background: Amoebic colitis is a common large intestinal infection caused by anaerobic parasite E. Histolytica. This study was done to compare efficacy of Periodic acid schiff’s (PAS) and immunohistochemical (IHC) marker in diagnosis of amoebic colitis.

Material & methods: 30 cases of amoebic colitis reported on Haematoxylin & Eosin (H&E) were studied.  Average number of trophozoites recognized in 10 high power fields on PAS and IHC were compared.

Observation & results:

1.      Out of 30 cases of amoebic colitis reported on routine H&E, 23 cases recognized with trophozoites on PAS while 20 out of 30 cases were positive for trophozoites on IHC.

2.      Number of trophozoites identified was 5 times on IHC and 2 times on PAS in comparison to H&E.

 Conclusion: IHC provides accurate diagnosis of amoebic colitis. It gives intense brown colour which makes trophozoites identification more easier.  With the use of IHC false positive diagnosis of amoebiasis can also be curtailed.