[Infantile and progressive papular mucinosis].

We comment the histologic and clinical features of a process studied in a 2-year old patient with neither clinical nor laboratory evidence of any other disease, being characterized by the existence of multiple papules, grouped but not confluent, asymptomatic, skin-coloured or slightly erythematous and located on the lumbar area. The outset of the lesions occurred at birth and their number has increased all through the first two years of file. The histologic image is consistent with mucin focus in the middle dermis, relatively well limited but without a perilesional capsule, associated to a fibroblast proliferation. The case is considered to be a reactive modification of fibroblasts with an alteration of their secretory capacity, which causes an increase of mucin with a decrease in the connective fibrillar components. The differences of this process with other primary or secondary cutaneous mucinosis especially with focal mucinosis are discussed. The non-specificity of the clinical features, makes it necessary to carry out the microscopic examination to get the correct diagnosis, being the surgical excision of the lesion the treatment of choice.