Diaper rash may occur due to overhydration of the stratum corneum.

Overhydration may occur due to diaper occlusion and accumulation of feces and urine.

Hydrated skin is more likely to suffer frictional damage than dry skin, the overhydration may also change the balance of resident flora and promote growth of C.

albicans, which is found in as many as 70% of infants with diaper dermatitis. Bacterial ureases in the stool degrade urea in urine, which releases ammonia; however, ammonia which increase the pH and reactivates fecal enzymes such as lipase and protease to irritate and disrupt the skin barrier.