Pyodermatitis Vegetans Associated with Multiple Myeloma

In 2013, a case was reported of a 78-year-old man with multiple myeloma who developed pyodermatitis vegetans (PD-PSV), a rare neutrophilic dermatosis typically associated with inflammatory bowel disease, but not previously reported in association with multiple myeloma. The patient presented with 11 nodules on his scalp, trunk, and right forearm, and plaques on his left shoulder, which were dark-red with papulopustular vegetation, erosion, ulcer, and crust, but were not painful or itchy. Laboratory tests and biopsies ruled out other conditions such as pemphigus vegetans, Sweet's disease, and cutaneous manifestations of multiple myeloma. The patient was treated with oral prednisolone, colchicine, and tacrolimus ointment, leading to complete resolution of the eruptions three weeks later. However, he required ongoing treatment due to recurring exacerbations. This case was the first reported instance of PD-PSV in a patient with multiple myeloma, suggesting that PD-PSV might be recognized as a dermatome of blood tumors in future cases.