Bullous amyloidosis.

The variety of cutaneous lesions in primary systemic or multiple myeloma-associated amyloidosis is impressive and includes purpura, waxy papules, tumors, plaques, alopecia, and, rarely, bullae. We report a patient in whom the diagnoses of amyloidosis and multiple myeloma were established after he presented with bullae and extensive infiltrated, purpuric plaques. Immunoelectrophoresis of the blister fluid revealed an IgA kappa monoclonal protein similar to that found in the patient's serum and urine.