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

Abstract

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).

Self-healing juvenile cutaneous mucinosis

“…Given the relative rarity of these diseases, establishing reliable diagnostic criteria can be a significant challenge. Podda et al 19 recently described the evolution of histologic findings in a 9-year-old girl given the diagnosis of cutaneous mucinosis of infancy. Early lesions were composed primarily of mucin deposition characteristic of cutaneous muci-nosis of infancy, whereas lesions present for a year demonstrated less mucin and more dermal fibrosis and fibroblast proliferation.…”

“…The authors suggest that cutaneous mucinosis of infancy may actually be the infantile presentation of lichen myxedematosus. 19 In their 1991 classification of cutaneous mucinoses, Rongioletti and Rebora 20 suggest that SHJCM is a distinct entity for which diagnosis must be based on both clinical and pathologic criteria. In a more recent review, the authors categorized the entity as a subtype of localized mucinosis, grouping juvenile and adult variants under the subset "self-healing papular mucinosis."…”

Primary paediatric cutaneous mucinoses

“…Cutaneous mucinosis of infancy (CMI) is one of the subtypes of localized lichen myxoedematosus (synonymous with papular mucinosis) . In particular, it is considered the paediatric variant of the discrete papular form or of acral persistent papular mucinosis . In the past, the terms lichen myxoedematosus, papular mucinosis and scleromyxoedema have been used interchangeably to describe the same disorder.…”

Cutaneous mucinoses

“…Sunlight and hormonal influences may cause exacerbations and induce mild pruritus. 144 This is the currently accepted view. Progression to cutaneous lupus erythematosus sometimes occurs, one of the reasons why Ackerman regards this condition as a variant of lupus erythematosus.…”