Scleromyxoedema is a rare primary cutaneous mucinosis characterized by a generalized papular and sclerodermoid eruption and typically associated with monoclonal gammopathy. We report an 81-year-old man with Waldenström macroglobulinemia on zanobrutinib who presented with rapidly progressive upper-limb edema, waxy papules, and skin thickening. Histopathology showed diffuse dermal mucin deposition with fibroblast proliferation and fibrosis, consistent with scleromyxoedema. Therapeutic plasma exchange led to partial cutaneous improvement, but the patient subsequently developed fatal intestinal ischemia. This case highlights the characteristic features and potential severity of scleromyxoedema and contributes to the limited literature on therapeutic plasma exchange in this condition.
Rubino et al. (Wed,) studied this question.