Erythema nodosum associated with Yersinia enterocolitica infection.

We report a 74-year-old woman who presented to hospital with fever, vomiting, diarrhea, and 2 weeks later developed erythema nodosum (EN) on the legs, and was diagnosed with Yersinia enterocolitica infection based on her clinical course and microbiological examination of the stool. She also had a complication of pancreatitis, which made the diagnosis challenging. We should suspect infection by Y. enterocolitica when diagnosing cases of EN with gastrointestinal symptoms. We assume EN is likely to appear 2 weeks after the onset of gastrointestinal symptoms from our case and other case reports.