Abnormalities in stratum corneum function in patients recovered from leprosy

Leprosy involves both the skin and peripheral nervous system. Leprosy patients display an increased incidence of xerosis and altered sensory thresholds, which persist in previously active skin sites. We assessed here whether alterations in stratum corneum (SC) function persist in cured leprosy, and the relationship of epidermal functional abnormalities to each clinical subtype of leprosy.

A total of 43 cured leprosy subjects and 29 normal control subjects were enrolled in this study. Basal skin surface pH, SC hydration, permeability barrier function as well as barrier recovery rates were measured over previously involved skin sites with a skin physiology monitor. One-way ANOVA and two-tailed Student's t test were used to determine the significance between 2 groups and 3 or more groups, respectively.

Competent barrier function was observed in all subtypes of cured leprosy subjects. All cured leprosy subjects except those with the borderline tuberculoid type exhibited a significantly lower SC hydration in comparison with normal subjects. Skin surface pH was significantly elevated in all cured leprosy subjects in comparison with normal subjects.

A varied spectrum of alterations in SC function remains in all subjects who have recovered from leprosy, but the spectrum of SC functional abnormalities varies with disease subtype.