Infants of less than 32 wk gestation have a defective epidermal barrier, with increased skin permeability and transepidermal water loss (TEWL). We studied the effect of a nonadhesive semipermeable dressing on the epidermal barrier of premature infants and on fetal skin transplanted to nude mice. Fifteen infants with a mean estimated gestational age of 27.7 wk and 16 human fetal skin grafts (estimated gestational age, 23-26 wk) transplanted to eight nude mice were studied. One lower leg (or skin graft) was treated and the other left untreated as a control. In the infants, TEWL was measured on control skin and treated skin (both through the dressing and after temporary dressing removal) on d 0, 1,2, 4, and 7. Bacterial and fungal cultures were also performed. In the mice, TEWL and skin blood flow were measured on d 0, 2, and 4. Biopsies were obtained on d 4 for a cell proliferation assay, histology, and electron microscopy. Treated infant skin showed a consistently lower bacterial number and a significantly decreased TEWL (measured through the dressing). There was also a significantly lower TEWL on the treated side, measured after temporary dressing removal, on d 1, 2, 4, and 7, documenting improved epidermal barrier function. The animal study revealed decreased TEWL and a nearly 2-fold greater d-4 keratinocytc proliferation (p = 0.01) in treated skin and decreased blood flow on d 4 in control skin (p = 0.01). There was no significant difference in the volume density of membrane coating granules or the morphology of intcrcorneocyte spaces. It is concluded that semipermeable dressings improve epidermal barrier function without increasing bacterial or fungal colonization in premature infants, and that increased cellular proliferation is associated with improved barrier function in semipermeable dressing-treated fetal skin.
ASJC Scopus subject areas
- Pediatrics, Perinatology, and Child Health