Etiology and pathophysiology of diaper dermatitis.
Common diaper dermatitis is a group of skin disorders that result from attack of the skin by physical, chemical, enzymatic, and microbial factors in the diaper environment. The integrity of healthy skin is compromised by the very nature of the diaper environment, and normal intact skin therefore remains an elusive goal of current diapering practices. Moist occlusion promotes miliaria, and causes an increase in the coefficient of skin friction. Skin hydration and an increase in skin pH result in impaired barrier function, and fecal enzymes begin to attack the skin, further degrading its normal ability to cope with its environment. Skin in this weakened state is susceptible to a variety of biological, chemical, and physical insults that can cause or aggravate diaper dermatitis. These include attack of the skin by fecal enzymes and other irritants in urine and feces, mechanical abrasion, and infection by C. albicans. Diapering is unquestionably an effective and convenient way of localizing an infant's excreta. Unfortunately, infant skin was not designed to operate continuously in the resulting environment, and is frequently unable to weather this assault. However, by improving the inherently adverse relationship between diapers and diapered skin, one can have a significant effect on the incidence and severity of diaper dermatitis. A diaper that keeps skin drier will result in skin that is less permeable to irritants, supports less microbial growth, is less susceptible to chafing damage, and has less contact with irritants in urine and feces. A diaper that maintains the environment closer to the normal acidic pH of skin will promote skin that is less permeable to irritants, and reduce the irritancy of fecal enzymes. Finally, a diaper that limits the mixing and spreading of urine and feces will result in less potentiation of enzyme activity and less contact of the skin with fecal irritants. Diaper dermatitis, by definition, cannot exist in the absence of diapers. Moreover, diaper dermatitis will become less troublesome for the infant population to the degree that diapered skin can be provided an environment closer to that of undiapered skin.