Idiopathic guttate hypomelanosis.
Idiopathic guttate hypomelanosis is usually associated with guttate hyperkeratosis, xerosis, and lentiginosis not related to the patient's age. Histologically, hypopigmented macules show remarkably decreased melanin, decreased DOPA-oxidase activity and a decreased number of melanosomes in the melanocytes with predominance of Stages I and II and small sizes. The epidermis is always atrophic. When scales are removed by scraping, hyperkeratotic lesions show, clinically and histologically, variable degrees of hypomelanosis; thus suggesting a relationship with the hypopigmented macules. These data suggest that idiopathic guttate hypomelanosis is the result of an early aging of the skin.
D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D008297:Male; D008543:Melanins / Q000032:analysis; D008875:Middle Aged; D014442:Monophenol Monooxygenase / Q000378:metabolism; D010859:Pigmentation Disorders / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D012867:Skin / Q000378:metabolism / Q000473:pathology*
D008543:Melanins; D014442:Monophenol Monooxygenase