A 20-year-old female presented to her primary care provider (PCP) for a rash with burning pain on her lower back that had been present for approximately 1 week. The rash consisted of multiple circular lesions with honey-colored discharge that were slightly scabbed over. Three weeks prior, she presented to the emergency room with a broken rib and an open wound on her back, after she had fallen off her horse, and it had stepped on her. The open wound initially cleared up, then later developed into the rash described above. 

One day prior to her PCP visit, she presented to a pediatric office for this rash; she was thought to have impetigo and shingles. After applying a prescribed ointment and noticing worsening symptoms, she presented to her PCP. An aerobic/anaerobic culture was ordered. No organisms grew anaerobically, but on day 2 of aerobic culture, flat, irregular, dull, buff-colored colonies appeared on 5% sheep blood, chocolate and colistin nalidixic acid agars. There was no growth on MacConkey agar. MALDI-TOF MS yielded no identification. A colony Gram stain was performed, which demonstrated septate hyphae, arthroconidia and chlamydospores. A colony tape prep with Lactophenol Aniline Blue demonstrated these same structures plus macroconidia. Subsequently, MALDI-TOF MS was performed using an alternative library, which led to organism identification.

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Author Information

Nicole J. Tarlton, Ph.D., D(ABMM), Director of Molecular Microbiology, Endeavor Health, Associate Director of Clinical Microbiology, Endeavor Health, Clinical Assistant Professor, University of Chicago Pritzker School of Medicine

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