Scleroderma associated with monoclonal gammopathy of undetermined significance

A 53-year-old female presented with itchiness in her back. She has a 5 years history of tightness of the skin on her face, neck, and torso bilaterally. She did not have other symptoms suggestive of systemic sclerosis (scleroderma), and her rheumatologic workup was negative. Skin biopsy showed increased dermal mucin confirming a diagnosis of scleredema. Further workup with serum protein electrophoresis (SPEP) showed an M-spike, confirming the diagnosis of monoclonal gammopathy of undetermined significance MGUS as the underlying pathology.