Utility of orcein stain and comparison with Masson trichrome stain in chronic intestinal pseudo-obstruction

Chronic intestinal pseudo-obstruction (CIPO) is caused by a plethora of primary and secondary causes, dominantly involving the neuromuscular tissue, interstitial cells of Cajal, or the connective tissue framework. The lack of the connective tissue framework, known as desmosis, is evaluated by Masson's trichrome (MT) or picrosirius red stains, both of which are recommended in the London classification. We evaluated the orcein stain in detecting desmosis in comparison to the MT stain. We performed both orcein and MT stains in six previously published cases of complete or partial desmosis along with six age-matched controls. Our results showed comparable results of the orcein stain as compared to the MT stain. Additional advantages of lower cost and a clearer background in orcein stain were noteworthy, whereas MT stain can be used for the detection of additional pathology. We believe that orcein stain can be used as a cheap alternative in resource-limited settings.