Year in Review: Pediatrics

February 1, 2007

Ambient humidity influenced the rate of skin barrier maturation in extremely preterm infants.

Pediatric dermatologists need to stay abreast and up to date in their field and are usually stretched for time to accomplish this. Regardless, Patricia A. Treadwell, M.D., a dermatologist and professor and assistant dean of pediatrics at Indiana University School of Medicine in Indianapolis, took it upon herself to fine-comb and review the essential developments in pediatric dermatology.

TEWL, ambient humidity

She cites a study where 22 preterm infants with an estimated gestational age (EGA) of 23 weeks to 27 weeks were randomized into two different groups after 1 week of age. Here, the TEWL was measured as an indicator of the skin barrier formation in the infants. The relative humidity of incubators was 50 percent to 75 percent. The study showed that the ambient humidity influenced the rate of skin barrier maturation in extremely preterm infants.

"High humidity was important in the first week because of substantial evaporative losses suffered by the infants. Thereafter, a more rapid skin barrier formed in the infants at the 50 percent relative humidity. Furthermore, optimal care for the infants depends on the individual needs of each patient," Dr. Treadwell tells Dermatology Times.

Atopic dermatitis and children

Dr. Treadwell reviews the data from an ongoing birth cohort study involving 2,162 infants, in which the timing of solid food introduction in infants and its importance in the development of atopic dermatitis (AD) and atopic sensitization was analyzed.

In the study, information on diet and symptoms and diagnoses of atopic dermatitis were collected semi-annually, and IgE levels controlled at age 2. The approach to the study design was to look at the prophylactic feeding guidelines which recommend delayed introduction of solid foods until 4 months to 6 months of age, with the ultimate goal to prevent atopic dermatitis in these patients.

Dr. Treadwell says that, "Results showed that the cohort study could not provide any evidence supporting a delayed introduction of solid foods beyond six months of life for the prevention of atopic dermatitis and atopic sensitization."

Dr. Treadwell cites another study where the effects of probiotics on atopic dermatitis was scrutinized and put to the test. Probiotics are defined as live microorganisms including lactobacillus and Bifidobacterium species as well as yeasts that may beneficially affect the host upon ingestion by improving the balance of the intestinal microflora. In the randomized double placebo controlled trial conducted in Perth, Australia, 56 children were administered lactobacillus fermentum VRI-033PCC twice a day orally for eight weeks.

Results showed that the reduction of the SCORAD index (a clinical tool used to objectively assess the severity of atopic dermatitis) noted in the probiotic group (p=0.03) was not seen in the placebo group. Ninety-two percent of children in the probiotic group had a SCORAD that was better than baseline at week 16, as compared to only 63 percent witnessed in the placebo group (p=0.01). At 16 weeks, 54 percent of the probiotic group had mild symptoms of atopic dermatitis, as compared to 30 percent of the placebo group, solidifying the obvious benefits of the use of probiotics in children with AD.

Varicella vaccination

Dr. Treadwell took a closer look at the efficacy of varicella vaccinations and their ability to alleviate symptoms in children.

She cites a study completed on a varicella outbreak reported in two Utah elementary schools. The parents of patients completed questionnaires about medical history and parents of children with recent varicella were interviewed and vaccination records were verified.

School A had 558 questionnaires (93 percent) and school B had 924 questionnaires (97 percent) returned, respectively. Of the 83 children who had varicella, 57 were unvaccinated and 26 were vaccinated. Varicella vaccine proved to be effective in 87 percent of cases reported.

Barring one exception, the vaccinated children exhibited milder symptoms of the illness. Dr. Treadwell says that the risk factors for the breakthrough in those who were vaccinated, yet developed symptoms, were eczema, a vaccination that took place more than five years before the outbreak and a vaccination that took place earlier than 18 months of age.