Association of pyoderma gangrenosum and sterile osteomyelitis in a patient having myelodysplastic syndrome with der(1;7)(q10;q10)

Neutrophilic dermatoses such as Sweet's disease and pyoderma gangrenosum (PG) are occasionally associated with myelodysplastic syndrome (MDS). We present here a 67‐yr‐old male having PG and sterile osteomyelitis in association with underlying MDS (refractory anemia) and Crohn's disease. To establish the diagnosis of MDS, sternal bone marrow puncture was performed, which showed chromosomal abnormality containing der(1;7)(q10;q10). After the puncture, he suffered from gradually progressive skin ulceration, flare, and bone pain. Magnetic resonance imaging (MRI) of the sternum showed severe inflammation in the sternum and the overlying subcutaneous tissue. All of the cultures obtained from the wound were negative for both bacteria and fungus. Biopsy was performed from the antero‐sternal skin lesion, which showed epidermal ulceration with prominent infiltration of neutrophils. He was thus diagnosed as having PG and sterile osteomyelitis, and was treated with prednisolone, which completely resolved the symptoms. We consider that the bone marrow aspiration in the present patient provoked PG and sterile osteomyelitis. As was previously reported by others, certain chromosomal abnormalities in MDS may be related with the development of neutrophilic dermatoses.