AimThis study aimed to identify the relationship between the skin barrier function after bathing at 2 weeks of age and subsequent facial skin problems during the first 6 weeks of life.MethodsA prospective observational study was conducted from July 2017 to February 2018 on healthy newborns aged 2 weeks. Skin barrier function was evaluated before bathing and at 30 and 90 min after bathing by measuring transepidermal water loss (TEWL), stratum corneum hydration (SCH), sebum secretion, and skin pH. Infantile facial skin problems were assessed using skin condition diaries maintained by a parent for 4 weeks.ResultsAnalysis of the data from 56 infants showed that 29 infants (51.8%) experienced facial skin problems from 2 to 6 weeks of age. A lesser change in the sebum secretion on the forehead before bathing to 90 min after bathing and a higher SCH of the forehead before bathing were less likely to result in facial skin problems (adjusted odds ratio [AOR] = 0.98, 95% confidence interval [CI]: 0.97–0.99; AOR = 0.96, 95% CI: 0.92–0.99).ConclusionsA greater change in the sebum secretion on the forehead before bathing to 90 min after bathing and a lower SCH of the forehead before bathing were associated with subsequent infantile facial skin problems, indicating that a better ability to recover after bathing is important to prevent facial skin problems. Future studies should identify factors that enhance the recuperative functions of infantile skin.

Infantile skin problems not only cause temporary pain and discomfort, but also have a long-term impact on health. Hence, the purpose of this cross-sectional study was to clarify the relationship between inflammatory cytokines and Malassezia fungal facial skin problems in infants. Ninety-six 1-month-old infants were examined. Facial skin problems and the presence of inflammatory cytokines in the forehead skin were assessed using the infant facial skin visual assessment tool (IFSAT) and the skin blotting method, respectively. Malassezia, a fungal commensal, was detected using forehead skin swabs, and its percentage in the total fungal population was analyzed. Infants with positive interleukin-8 signals were more likely to have severe facial skin problems (p = 0.006) and forehead papules (p = 0.043). No significant association between IFSAT scores and Malassezia was found, but infants with forehead dryness had a lower percentage of M. arunalokei in the total fungal population (p = 0.006). No significant association was observed between inflammatory cytokines and Malassezia in the study participants. Longitudinal studies on the development of facial skin problems in infants are warranted to investigate the involvement of interleukin-8 and devise preventive strategies in the future.

This study aimed to examine newborn-oriented and environmental factors of newborn skin barrier functions. Methods: This was a retrospective secondary analysis of 227 newborns from a previous study. Newborn skin barrier functions were measured on the fourth day after birth via the following parameters: stratum corneum hydration, transepidermal water loss, skin pH, and sebum secretion. Skin barrier functions were measured at four body sites; their averaged values were used for the analysis. The associations among skin barrier functions, newborn-oriented factors, and environmental factors were evaluated. Multiple regression analysis was performed using a forced entry method, and independent variables for which p-values were <.05 in Student's t test, analysis of variance, and Pearson's correlation analysis were included.Results: A total of 211 participants were analyzed. The mean ± standard deviation values of stratum corneum hydration, transepidermal water loss, skin pH, and sebum secretion were 28.58 ± 8.40 and 7.28 ± 2.02 g/m 2 /h, 5.77 ± 0.53, and 23.59 ± 15.89 μg/cm 2 , respectively. Newborn-oriented factors (gestational days, weight, amount of vernix, and parity) and environmental factors (birth season)were significantly associated with one or more skin barrier functions. Conclusions: Newborn-oriented (including labor-and delivery-related) and environmental factors were associated with the skin barrier functions. The newborn maturity level, newborn sex, environmental temperature, and humidity may affect skin barrier functions in newborns. Further studies should focus on the effects of these factors on newborn skin barrier assessments, and develop tailored skincare strategies based on their characteristics.