Summary

Scleromyxedema is a rare, chronic cutaneous mucinosis characterized clinically by diffuse indurated plaques, numerous waxy papules, and potential for systemic involvement, including neurological, pulmonary, and gastrointestinal complications. It can significantly impact the clinical course and patient prognosis [1].

Histologically, scleromyxedema typically manifests in two main forms. The classic form, the most common variant, is characterized by dense mucin deposition within the dermis, an increase in fibroblasts, and thickened collagen. The granuloma annulare-like variant, accounting for approximately 23% of cases, mimics granuloma annulare and is characterized by interstitial granulomatous infiltration and, in some cases, palisaded granulomas within the dermis. This unusual variant presents a significant diagnostic challenge due to its overlap with other granulomatous conditions, potentially causing diagnostic delays [2].

The lack of standardized treatment regimens makes managing scleromyxedema complex. Intravenous immunoglobulin (IVIG) has emerged as a leading therapeutic option, demonstrating efficacy in controlling both cutaneous and systemic manifestations. Other options include systemic steroids, thalidomide, retinoids, and melphalan [3].

These cases underscore the challenges of recognizing the clinical and histologic variability of scleromyxedema, which may lead to a delay in the diagnosis. Early diagnosis is critical given the potential for systemic involvement (neurological, gastrointestinal, and muscular) and the association of scleromyxedema with monoclonal gammopathy of undetermined significance (MGUS), which might progress to multiple myeloma. Consequently, timely hematologic evaluation and ongoing surveillance are warranted.