Pyoderma gangrenosum confused with congenital preauricular fistula infection: A case report

Abstract

BACKGROUND

Pyoderma gangrenosum resulting from or associated with congenital preauricular fistula is rarely reported.

CASE SUMMARY

We report a rare case of pyoderma gangrenosum misdiagnosed as preauricular fistula infection. To our knowledge, this is the first report to describe pyoderma gangrenosum originating from the site of preauricular fistula. The lesion continued expanding even after combined treatment of systemic antibiotics and thorough debridement. Taking into account the possibility of pyoderma gangrenosum, we applied soft care with normal saline and Vaseline gauze dressing. Systemic corticosteroids were not used until intestinal Clostridium difficile was controlled. No local recurrence was noted at the 12-mo follow-up.

CONCLUSION

This case highlights the necessity of considering rare diseases, such as pyoderma gangrenosum, when the preauricular sinus deteriorates with general management. The treatment strategy is mutually conflicting between pyoderma gangrenosum and infection of the preauricular sinus.

Keywords: Preauricular fistula; Pyoderma gangrenosum; Glucocorticoids; Case report

Core tip: Acute infection of the preauricular sinus is common in clinical practice, while pyoderma gangrenosum is rare. We here report a rare case of pyoderma gangrenosum that was initially treated as common preauricular sinus infection and did not respond to traditional management. Pyoderma gangrenosum is a noninfectious inflammatory dermatosis that presents as an inflammatory disorder of the skin. The most common comorbidity is inflammatory bowel disease. Diagnosis of pyoderma gangrenosum should be considered when standard management is not effective or it is complicated with inflammatory bowel diseases.