Idiopathic pyoderma gangrenosum or a systemic disease predictor?

Pyoderma gangrenosum (PG) is an auto inflammatory non-infectious neutrophilic dermatosis often presenting with pustules or nodules that progress to ulcers. PG has specific clinical features and non-characteristic histology findings. Some systemic diseases such as Crohn’s disease, ulcerative colitis, rheumatoid arthritis, hematologic malignancy or autoimmune disease are commonly associated with PG. One of the most characteristic features of pyoderma gangrenosum is pathergy, which is the appearance of new lesions at sites of trauma, including surgical wounds. We present a 62-year-old male with a large ulceration on the left lower leg after a bee sting.