Solitary Cutaneous Focal Mucinosis

Solitary cutaneous focal mucinosis is a unique condition defined by the presence of mucin, a hyaluronic acid complex, in the dermis. The lesion typically presents as an isolated, asymptomatic papule or nodule on the extremities or back and is not associated with any systemic condition. Conversely, multiple cutaneous focal mucinosis present with numerous skin lesions has been found to be associated with systemic diseases such as scleromyxedema, systemic lupus erythematous, and thyroid disease. Therefore, additional laboratory investigation should be considered when multiple cutaneous focal mucinosis is discovered. The case of a 37-year-old man with solitary cutaneous focal mucinosis is discussed. The skin lesion presented as an asymptomatic nodule on his right upper shoulder; microscopic evaluation established the diagnosis, and laboratory investigation was negative for any associated conditions. Similar to previous reports of solitary cutaneous focal mucinosis, our patient provides additional supporting evidence that laboratory studies for mucin-associated systemic disease are not required for individuals who present with cutaneous focal mucinosis consisting of only a solitary skin lesion.