A 65-year-old gentleman originally from Tonga presented with a chief complaint of altered mental status and confusion. The history was mostly given by his daughter and wife, who note the patient has had difficulty with memory and speech for the prior 3 days. His past medical history was significant for a deceased donor kidney transplant about 2 years prior to the current presentation. A magnetic resonance imaging (MRI) scan of his head was ordered and showed a 45 by 35-millimeter mass in the left frontal lobe, consistent with an abscess, without evidence of surrounding edema or hydrocephalus. He was urgently admitted and sent to neurosurgery where a craniotomy was performed, and several milliliters of purulent material were removed and sent to microbiology. Primary Gram stain showed faint gram-positive beaded and branching rods. A modified acid-fast stain was performed and showed pink branching rods. Chalky white colonies appeared on Chocolate agar plates after 2 days of incubation.

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Author Information

Jaron Listar-Guest, Medical Technologist Microbiology Team Lead (ASCP), Mayo Clinic Arizona.
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