ABSTRACT
The effect of urine and feces on the skin is a contributing factor to the development of incontinent and diaper dermatitis. The objective of this research was to evaluate skin effects of a given urine or fecal sample on the donor child and/or an adult caregiver, both of whom would be exposed to the biological material in course of daily life. Methods: Urine was evaluated under a variety of experimental skin conditions: normal (N), compromised by tape stripping (C), hydrated by prolonged exposure to water via occlusive patch (H), and hydrated/compromised (H/C). After pre-treatment, sites were patched (3 times of 24-h each) with 0.5 ml infant urine, saline (negative control) or 0.3% sodium lauryl sulfate (SLS, positive control). Fecal material was evaluated using a 4-h patch followed by tape stripping of selected sites. Results: In the urine study, a single 24-h patch produced a significant elevation of pH compared to both the negative (saline) and positive (sodium lauryl sulfate) controls for all experimental skin conditions. Erythema produced by urine was intermediate between the negative and positive controls, and significantly different from the negative control on the N and C skin test sites. All three materials produced an increase in hydration of the skin. The single 4-h patch of fecal material produced significant erythema, a significant elevation of pH, and a significant increase in TEWL. Recovery to pre-treatment levels was observed by the next day on sites that received no further treatment. However, on sites patched with fecal material, then further compromised by tape stripping, recovery to pre-treatment levels for erythema and TEWL were delayed. Conclusion: These studies indicate that urine appears to have an inherent low level irritant property when in continuous contact with skin for 24 to 48 hours. With relatively short exposures of 4 hours fecal material causes visible erythema, increases in pH and TEWL, and decreases in stratum corneum resilience to the subsequent insult of tape stripping. Results re-inforce the utility of modern diapers and incontinent products, utilizing superabsorbent materials, to effectively absorb wetness, keeping skin dryer and minimizing adverse skin effects.