Keratosis lichenoides chronica: a pediatric case.

Keratosis lichenoides chronica (KLC) is a rare chronic disorder of keratinization characterized by lichenoid hyperkeratotic papules arranged in a linear pattern, erythematosquamous plaques and seborrhea-like dermatitis on the face. Adults between 20 and 50 years of age are usually affected, but the disease is very uncommon in childhood. Our purpose was to study the clinical and histopathologic findings and course of KLC in one pediatric case. Detailed clinical data were studied. Two punch biopsies were performed and histopathologic features were compared with those of other reported cases of KLC. In our patient, a 4-year-old boy, the clinical features of the lesions did not deviate notably from those of other cases of KLC. The histologic pattern of the papules was typical of KLC, while that of the erythematosquamous plaques showed some dyskeratotic keratinocytes. The histologic pattern of the erythematosquamous lesions is peculiar in our case, whereas only a nonspecific pattern is reported in the literature. The papular and erythematosquamous lesions showed similar histopathologic features suggesting that they could be different degrees of evolution of the same lesion.