Deux cas de kératose lichénoïde chronique dans une même fratrie. Réponse favorable à la photothérapie UVB

KLC is uncommon in childhood and familial occurrence is very rare. Clinically, thick keratotic papules arranged in parallel lines or small networks cover the dorsal aspects of the limbs symmetrically. The face may be affected by a seborrhoea-like dermatitis. Histology typically shows alternating acanthosis and atrophy, with focal parakeratosis. An extensive lichenoid lymphohistiocytic and plasmocytic infiltrate is demonstrated in the dermis. The course is chronic. Spontaneous resolution may occur. Sunlight has been shown to be effective in the few paediatric cases reported. Narrow-band UVB phototherapy appears to be an effective therapeutic option.