Auricular pyoderma gangrenosum with penetration in a patient with rheumatoid arthritis

Auricular pyoderma gangrenosum with penetration in a patient with rheumatoid arthritis Dear Editor, Pyoderma gangrenosum (PG) is a disease characterized by refractory, sterile, deep ulcers, which frequently involve the lower extremities in women aged between 20 and 60 years. 1 By contrast, PG involving other peripheral structures such as the ear is rare.PG is often associated with several systemic diseases such as rheumatoid arthritis (RA), inflammatory bowel disease (IBD) and hematological diseases.We herein describe a case of PG involving the ear with penetration in a patient with severe RA.An 83-year-old woman was admitted to our hospital, complaining of multiple ulcers on the head and neck and lower extremities.She had been suffering from RA and associated interstitial lung disease for 20 years, and had been treated with non-steroidal anti-inflammatory drugs and prednisolone (2.5 mg/ day) at the visit to our hospital.Physical examination showed multiple deep ulcers on the scalp, ear, knee, lower legs, toes and sole (Fig. 1a).The ulceration was undermined and the border was slightly elevated and edematous.The surface presented reddish granulation and was partially covered with necrotic tissues.Furthermore, an ulcer of the earlobe was penetrated (Fig. 1b).Disease Activity Score of 28 joints -C-reactive protein (DAS28-CRP) score was 5.26 and neither rheumatoid nodules nor splenomegaly were present.Laboratory examination showed increased white blood cell counts (17 700/lL, with 90% neutrophils and 1% lymphocytes), CRP (11.6 mg/dL), positive rheumatoid factor (93 IU/mL, normal < 20), anti-cyclic citrullinated peptide (CCP) antibody (370 U/mL, normal < 4.5) and matrix metalloproteinase-3 (MMP-3) (139 ng/mL, normal; 17.3-59.7)levels.Further investigations for cryoglobulin, M-protein, myeloperoxidase-anti-neutrophil cytoplasmic antibody and proteinase-3-anti-neutrophil cytoplasmic antibody were all negative.Cultures for bacteria were sterile.