Comparative Study of Enzymatic Inhibition in pH Buffering Barriers in Ostomy Care

Over 140,000 ostomy surgeries are performed in the United States annually. This procedure involves creating an artificial passage between the lumen of a hollow organ and the skin to pass waste material (dejecta) and is performed to treat conditions including autoimmune or inflammatory bowel disease, trauma, and cancer. These patients add to the existing population of 750,000-1 million Americans living with ostomies, reliant on external collection products to replace the dejecta retention functionality of the excised or bypassed colon, small bowel, or bladder. Bodily waste is excreted out of the surgical opening known as the stoma and collected into an ostomy pouch. The pouch is affixed to the patient’s abdomen around the stoma via a skin-protecting hydrocolloid barrier that is designed to absorb and manage moisture while maintaining load-bearing adhesion.

Despite these design features, leaked dejecta from the stoma can come in contact with the skin surrounding the stoma, leading to skin issues such as moisture associated skin damage (MASD), peristomal contact dermatitis, and enzymatic injury. Ileostomy dejecta typically has a neutral pH and is rich in enzymes that retain pH dependent activity. These neutral pH environments create optimal conditions for high enzymatic activity that can lead to irritation and breakdown of the skin, which normally has an acidic pH.

The relationship between pH level and enzymatic activity in ostomy care is an active area of research. To better understand this relationship, pancreatic proteases commonly found in dejecta (trypsin, chymotrypsin, elastase) were studied in vitro in different buffered pH systems. Next, marketed products commonly used as ostomy skin barriers were also studied to understand their ability to buffer pH and the resultant effect on enzymatic activity. These enzymes were reconstituted in the various buffered pH solutions, and their protease activity was measured kinetically using a fluorescence-based assay.

Enzymatic activity was shown to have a strong pH dependence both in samples of individual enzymes and of various combinations. The activity of commonly found enzymes as a function of pH was determined, and this information can help elucidate their role in peristomal skin complications in ostomates. Furthermore, some marketed products were shown to be more effective than others in buffering to an acidic pH leading to reduced enzyme activity. These results provide support for the ability of certain marketed ostomy barrier products to reduce enzymatic activity on peristomal skin through pH modulation.