Scleredema adultorum associated with a monoclonal gammopathy and generalized hyperpigmentation

Scleredema associated with a monoclonal gammopathy and generalized skin pigmentation is described in a 56-year-old man with hyperlipoproteinemia and cardiovascular disease. The patient had IgG-lambda paraproteinemia, without any evidence of multiple myeloma or immunoglobulin deposition in affected skin. Ultrastructural studies of pigmented lesional skin showed increased transfer of melanosomes to basal keratinocytes and dermal melanophages containing complex melanosomes. In addition, cytoplasmic, electron-opaque lipid droplets were seen in approximately every third keratinocyte or melanocyte, while only an occasional dermal cell contained lipid droplets. The hyperpigmentation appeared to be directly related to the scleredema, while the lipid deposition in skin was a likely consequence of the hyperlipoproteinemia. The findings further support the contention that paraproteinemia and hyperpigmentation may, in some patients, be associated features of scleredema adultorum.