Abstract: A 71-year-old female presented with ulcer on both lower limbs with pain for more than 20 months. The biopsy features were in accordance with the diagnosis of pyoderma gangraenosum. Immunoelectrophoresis showed monoclonal bands of IgGκ monoclone brand. Bone marrow puncture showed active myelodysplasia, abnormal plasma cells, immature plasma cells accounted for 29.5%. The diagnosis of multiple myeloma with pyoderma gangraenosum was made.

Key words: pyoderma gangraenosum, multiple myeloma