Epidermal permeability barrier recovery is delayed in vitiligo-involved sites

Abstract

Background/objectives: Prior studies have demonstrated that both the skin surface pH and epidermal permeability barrier function vary with skin pigmentation types. Although melanin deficiency is the main feature of vitiligo, alterations in cutaneous biophysical properties in vitiligo have not yet been well defined. In the present study, stratum corneum (SC) hydration, the skin surface pH and epidermal permeability barrier function in vitiligo were evaluated.

Methods: A total of 30 volunteers with vitiligo comprising 19 males and 11 females aged 13-51 years (mean age: 27.91 +/- 2.06 years) were enrolled in this study. The skin surface pH, SC hydration, melanin/erythema index and transepidermal water loss (TEWL) were measured by respective probes connected to a Courage-Khazaka MPA5. SC integrity was determined by measuring the TEWL following each D-Squame application. The barrier recovery rate was assessed at 5 h following barrier disruption by repeated tape stripping.

Results: In addition to SC hydration, both melanin and erythema index were significantly lower in vitiligo lesions than in contralateral, nonlesional sites, while no difference in skin surface pH between vitiligo-involved and uninvolved areas was observed. In addition, neither the basal TEWL nor SC integrity in the involved areas differed significantly from that in the uninvolved areas. However, barrier recovery in vitiligo-involved sites was significantly delayed in comparison with uninvolved sites (40.83 +/- 5.39% vs. 58.30 +/- 4.71%; t = 2.441; p < 0.02).

Conclusion: Barrier recovery following tape stripping of the SC is delayed in vitiligo. Therefore, improvement in epidermal permeability barrier function may be an important unrecognized factor to be considered in treating patients with vitiligo.

Fig. 1

Comparison of basal SC properties between vitiligo-involved and uninvolved sites. The SC properties were measured as described in the Materials and Methods section. The unpaired two-tailed Student t test with Welch's correction was used to determine the significance between vitiligo-involved and uninvolved sites. The paired two-tailed Student t test was used to determine the significance in skin surface pH before and after 5 DSquame applications. a Comparison of melanin/erythema index. b SC hydration as determined by measuring SC capacitance. c Skin surface pH. d Basal permeability barrier function.

Fig. 2

Comparison of barrier recovery rate between vitiligo-involved and uninvolved sites. Barrier perturbation was achieved by repeated D-Squame applications. The TEWL was measured at involved and contralateral uninvolved sites immediately and 5 h after barrier disruption. The unpaired two-tailed Student t test with Welch's correction was used to determine significance.

Fig. 3

Comparison of SC integrity between vitiligo-involved and uninvolved sites. The TEWL was measured at vitiligo-involved and contralateral uninvolved sites at baseline and immediately after each D-Squame application. The unpaired two-tailed Student t test with Welch's correction was used to determine significances between vitiligo-involved and contralateral uninvolved sites.