Hair Casts and Cutaneous Spicules in Multiple Myeloma

The document described a case of a 70-year-old woman with multiple myeloma who exhibited cutaneous spicules on her nose and hair casts on her scalp and eyelashes. Biochemical analysis confirmed that these spicules and hair casts contained monoclonal IgG protein, the same as found in her serum. Histopathologic examination revealed hyperkeratosis and parakeratosis in the spicules and amorphous eosinophilic material in the hair casts. Despite various topical treatments, significant improvement was only observed after chemotherapy, which reduced her serum IgG levels. The study proposed that hair casts should be recognized as a characteristic finding in multiple myeloma, alongside cutaneous spicules.