Comparison of Clinical Features between Pyoderma Gangrenosum Concomitant by Inflammatory Bowel Disease and Idiopathic Pyoderma Gangrenosum

BACKGROUND Pyoderma gangrenosum (PG) is a rare neutrophilic dermatosis that is highly associated with inflammatory bowel disease (IBD). Certain PG patients with no systemic disorders have been diagnosed with idiopathic PG. This study sought to clarify the difference between PG with IBD and idiopathic PG based on clinical features, laboratory tests, and medications. METHODS Twelve patients with PG and IBD and 24 patients with idiopathic PG, who were hospitalized in Peking Union Medical College Hospital from 2000 to 2017, were retrospectively categorized into the IBD group and control group, respectively. Data of clinical features, laboratory tests, and medications were collected and compared between the two groups. RESULTS Both groups were similar with respect to their clinical features. However, the IBD group had an increased occurrence of arthralgia or arthritis (58.3% vs. 12.5%, P = 0.007), anemia (83.3% and 29.2%, P = 0.004), and an increased percentage of antineutrophilic cytoplasmic antibody (ANCA)-positive patients (85.7% and 0.0%, P < 0.001), compared to the control group. CONCLUSION PG patients with IBD had increased occurrence rates of arthralgia or arthritis, anemia, and ANCA-positive status compared to idiopathic PG patients.