DEVELOPMENT OF SKIN BARRIER FUNCTION IN PREMATURE-INFANTS

Histologic analysis suggests that epidermal development is complete in utero at approximate to 34 wk gestational age. Infants born more prem aturely have elevated rates of both transepidermal water loss and tran scutaneous heat loss, and have difficulty maintaining homeostasis. The underdeveloped integument is also a portal of entry for infection and the percutaneous uptake of toxins. Previous measurements of transepid ermal water loss have suggested that, regardless of gestational age, c ompetent barrier function is attained within 2-4 wk postnatal age. In this study we have utilized another noninvasive biophysical technique, low frequency impedance spectroscopy, to complement transepidermal wa ter loss measurements. We present longitudinal data from infants rangi ng from 23 to 32 wk gestational age. The results suggest that, for ult ra-low birth weight infants (23-25 wk gestational age), the complete d evelopment of a fully functional stratum corneum can require significa ntly longer than 4 wk. In contrast, the data from the older infants su ggest that a postnatal existence period of 2-4 wk may not be necessary to attain functional maturity, because infants born at 30 and 32 wk g estational age were found to have barrier function comparable with tha t of adults.