Linear and whorled hypermelanosis (LWNH) is a benign skin condition characterized by onset in infancy of hyperpigmented regions composed of small light brown spots that coalesce with age and follow the lines of Blaschko on the trunk and limbs. The soles, palms, face, and mucous membranes are spared. The lesions are asymptomatic and progress with age; affected individuals have no accompanying extradermal features. There is no previous history of inflammation on affected areas (summary by Kalter et al., 1988). [from
OMIM]