Tinea capitis caused by Trichophyton rubrum is a rare event worldwide. We report on an elderly otherwise healthy man with inflammatory fungal disease of the scalp caused by this pathogen. He had no signs of concomitant mycosis of the skin and nails and no underlying immunosuppressive disease. The fungal infection primarily had been misdiagnosed in terms of a pyoderma. Failure of antibiotic treatment, a positive mycological study and molecular diagnostics eventually led to the correct diagnosis. After systemic and local administration of terbinafine the lesion improved totally.