Atypical Presentation of Rupioid-Like Tinea Corporis due to a Rare Nannizzia Incurvata Infection

Tinea corporis, a superficial fungal skin infection of the trunk and extremities, typically presents as scaly, erythematous plaques with an active border. However, atypical presentations, especially those caused by uncommon dermatophytes, can complicate diagnosis. Here, we report an unusual case presenting with an oyster-like (rupioid) lesion on the right shoulder, a presentation not previously documented. Molecular analysis of the internal transcribed spacer (ITS) region of ribosomal DNA identified Nannizzia incurvata, a rare dermatophyte within the Nannizzia gypsea complex. The patient was successfully treated with a four-week course of oral itraconazole and topical terbinafine. This case underscores the importance of recognizing unusual clinical presentations and using molecular techniques for accurate pathogen identification. Understanding the characteristics and clinical significance of this uncommon pathogen in human infections will contribute to better diagnosis and management strategies.