Szymanski Kathryn,  Pfeifer Cory,  Friedman Neil,  Kuwabara Michael

Final Pr. ID: Poster #: CR-033

Balamuthia mandrillaris is an amoeba that causes an uncommon but deadly encephalitis, referred to as granulomatous amoebic encephalitis (GAE). The highest incidence reported worldwide has occurred in America, and within the United States, it has been highest in the Southwest affecting predominantly children and young men of Hispanic ethnicity. Clinical presentation of GAE includes fever, headache, nausea, vomiting, lethargy, irritability, stiff neck, hallucinations, photophobia, and seizures. Our patient was a Hispanic male child living in Arizona. The patient presented at 3 years of age for severe encephalitis. Symptoms included difficulty with balance, gait, and sitting up and seizure-like activity. Initial CT showed an area of decreased density consistent with edema in the left frontoparietal lobe. Rapid progression was seen on further imaging over the length of the patient’s hospital stay revealing diffusion restriction, necrosis/blood products, edema, and hemorrhage. The patient expired from tonsillar herniation 22 days after the onset of initial symptoms and 4 days after admission to our institution. While there are multiple biochemical techniques that can test for B. mandrillaris, they are rarely employed for multiple reasons stemming from the rare occurrence of this infection. Balamuthia mandrillaris can cause a lethal brain infection. Because of the fatal nature of this infection, we propose 1) testing should be considered if a patient presents with progressing encephalitis on imaging and other pathogenic etiologies are ruled out and 2) the threshold to treat empirically should be low due to the fatal nature of the infection. Read More

Authors:  Szymanski Kathryn , Pfeifer Cory , Friedman Neil , Kuwabara Michael

Keywords:  amoeba, Balamuthia mandrillaris, brain infection

Muthee Bernadette,  Ombati Kevin,  Wanyonyi Benjamin

Final Pr. ID: Poster #: CR-040

Scedosporium apiospermum is a filamentous soil-dwelling fungus and an emerging opportunistic pathogen that typically affects immunocompromised individuals, causing pulmonary, sinus, or soft tissue infections. However, central nervous system (CNS) involvement is rare, particularly in children, and is associated with delayed diagnosis, limited treatment options, and a high mortality rate.
We report a challenging case of a previously healthy 5-year-old boy who presented with sudden-onset seizures and anisocoria. Initial contrast-enhanced CT of the brain revealed numerous ring-enhancing hypodense lesions diffusely infiltrating the right cerebral hemisphere, basal ganglia, thalamus, and brainstem, crossing the midline, and resulting in marked mass effect, leftward midline shift, right uncal and subfalcine herniation, with obstructive hydrocephalus.
Subsequent MRI of the brain demonstrated multiple infiltrative lesions of varying sizes with peripheral T2-weighted hypointensity, central restricted diffusion, irregular ring enhancement, and a distinct “target sign,” accompanied by extensive surrounding vasogenic edema. These findings mimicked diffuse high-grade glioma, tuberculous abscess, and pyogenic abscess.
Chest radiography revealed bilateral hilar soft-tissue fullness suggestive of lymphadenopathy.
Due to the atypical imaging features and rapid neurological decline, a stereotactic brain biopsy was performed, confirming invasive fungal infection caused by Scedosporium apiospermum. Despite supportive neurocritical care and initiation of antifungal therapy, the patient rapidly deteriorated and succumbed to severe neurological complications a few days later.
This case highlights the diagnostic complexity of intracranial Scedosporium apiospermum infection in pediatric patients, particularly due to its radiological similarity to neoplastic and other infective conditions. Key imaging indicators, including peripheral T2 hypointensity, central diffusion restriction, and the “target sign,” may suggest a fungal etiology and should prompt early biopsy. Timely recognition and initiation of targeted antifungal therapy are crucial but may not prevent fatal outcomes in extensive CNS involvement. Increased awareness of this rare but lethal infection is essential to avoid delays in diagnosis and improve clinical decision-making. Read More

Authors:  Muthee Bernadette , Ombati Kevin , Wanyonyi Benjamin

Keywords:  Magnetic Resonance Imaging, Brain, Infection