An unusual case of infantile dermal mucinosis

Cutaneous Mucinosis of Infancy: A Rare Congenital Case with Coexisting Progressive, Eruptive, and Spontaneously Involuting Lesions

Cutaneous mucinosis in infancy is rare. We report an infant with multiple congenital papules distributed over the trunk, neck, and extremities. These papules were mainly dispersed, but they also coalesced into plaques. Histopathologic findings showed features of cutaneous mucinosis of infancy (CMI). Over 2 years of follow-up, we observed that the preexisting lesions on the lower back and left trunk progressively increased in size, and a few new scattered papules continued to appear, mainly on the trunk; several lesions spontaneously resolved with no further complications. CMI is considered to be a persistent cutaneous disorder, even though spontaneously regressing cases have rarely been reported. This case demonstrates the broad clinical spectrum of CMI, with progressive, eruptive, and spontaneously involuting lesions all present in the same patient. This condition should be considered in the differential diagnosis of congenital or infantile-onset papules and plaques, especially those yellowish in color.

Nodular lichen myxedematosus during childhood: a case report

Nodular lichen myxedematosus (LM) is a rare disease and is one of the five subtypes of localized LM. It is distinctly characterized by multiple nodules on the trunk and limbs with or without papular lesions. A healthy 6-year-old boy presented with complaints of "knots" on his right chest, upper limb, and thigh for 4 months. To our knowledge this is the first case of nodular LM reported in a child.

Cutaneous mucinosis of infancy: is it a real entity or the paediatric form of lichen myxoedematosus (papular mucinosis)?

We describe a girl presenting with a childhood dermal mucinosis in which we had the unique opportunity to find all the transitional histological features of lichen myxoedematosus (papular mucinosis), from its early focal mucin deposition in the reticular dermis to its late findings of interstitial mucin deposition, dermal fibrosis and fibroblast proliferation. Her father reported having had similar lesions when he was a child, which completely disappeared during adolescence. This case, and a re-evaluation of the literature, suggests that cases of cutaneous mucinosis of infancy that are not hamartomatous conditions such as mucinous naevi are in fact the infantile presentation of lichen myxoedematosus (papular mucinosis) and, in addition to other cases in the literature, suggests a genetic and familial factor in lichen myxoedematosus (papular mucinosis).

Updated classification of papular mucinosis, lichen myxedematosus, and scleromyxedema

Lichen myxedematosus (LM) is an idiopathic cutaneous mucinosis; its classification dates back to 1953, when Montgomery and Underwood distinguished 4 types of LM: a generalized lichenoid eruption, later called scleromyxedema, a discrete papular form, a localized or generalized lichenoid plaque form, and an urticarial plaque form. In the literature, the terms LM, papular mucinosis, and scleromyxedema have been often used indiscriminately as synonyms, but most reported cases of LM or papular mucinosis without indication of the subtype appear in fact to be cases of scleromyxedema. On the basis of personal experience, the anatomoclinical manifestations of published cases of LM, papular mucinosis, and scleromyxedema are reviewed to distinguish clearly between a generalized form with systemic, even lethal, manifestations and a localized form, which does not run a disabling course. LM includes two clinicopathologic subsets: a generalized papular and sclerodermoid form (also called scleromyxedema) and a localized papular form. Diagnosis of scleromyxedema should fulfill the following criteria: (1) generalized papular and sclerodermoid eruption; (2) mucin deposition, fibroblast proliferation, and fibrosis; (3) monoclonal gammopathy; and (4) the absence of thyroid disease. The criteria for localized LM are as follows: (1) papular or nodular/plaque eruption; (2) mucin deposition with variable fibroblast proliferation; and (3) the absence of both monoclonal gammopathy and thyroid disease. The localized form is subdivided into 5 subtypes: (1) a discrete papular form involving any site; (2) acral persistent papular mucinosis involving only the extensor surface of the hands and wrists; (3) self-healing papular mucinosis, of a juvenile and an adult type; (4) papular mucinosis of infancy, a pediatric variant of the discrete form or of acral persistent papular mucinosis; and (5) nodular form. A third group of atypical or intermediate forms, not meeting the criteria for either scleromyxedema or the localized form, includes cases of (1) scleromyxedema without monoclonal gammopathy, (2) localized forms with monoclonal gammopathy and/or systemic symptoms, (3) localized forms with mixed features of the 5 subtypes, and (4) not well-specified cases.

Self-healing infantile familial cutaneous mucinosis

Childhood cutaneous mucinoses have been rarely reported and are difficult to classify. We describe two brothers who developed multiple, extensive cutaneous lesions during the first few months of life. Histologically the lesions were composed of mucin deposits in the dermis. In the first patient, the lesions spontaneously disappeared over the years. We believe that familial self-healing cutaneous mucinosis represents a unique entity not previously reported.