Multiple Spontaneous Intracranial Abscesses in an Adolescent Female

Introduction: Brain abscesses (BAs) make up only 1-2% of all intracranial masses but carry a mortality rate of 17-32%. The vast majority develop via contiguous spread from nearby infectious sources such as sinusitis, mastoiditis, or otitis. When a local source is not identified, further evaluation is necessary. We present the case of a teenager with multiple BAs of an unclear etiology.


Description: A 17-year-old obese female with one-week of nausea, vomiting, and lethargy, followed by acute encephalopathy (auditory/visual hallucinations & incomprehensible speech). Initial CT head showed “multiple bilateral soft tissue densities with vasogenic edema”. Broad-spectrum antibiotics (vancomycin, ceftriaxone & metronidazole) were started. Lumbar puncture revealed an elevated opening pressure (>35mmHg), concerning for intracranial hypertension (ICH). CSF Gram stain and cultures were unremarkable. MRI brain confirmed “7 ovoid, rim-enhancing lesions”, but did not reveal an adjacent source of infection. Seizure prophylaxis was started for the extensive parenchymal lesions. Findings of papilledema (grade IV) and chronic headaches prompted use of acetazolamide. Due to enlarging lesions despite antibiotics, she underwent a brain biopsy; samples grew Streptococcus intermedius. She was briefly discharged on IV antibiotics but readmitted for new visual changes, requiring a washout with Neurosurgery. Her neurologic symptoms improved, and she continued with long-term parenteral antibiotics.

Given lack of a contiguous source of infection, her abscesses were presumed to be secondary to hematogenous spread. An extensive evaluation was done to find a potential source for septic emboli, which was largely negative except for periodontal disease. Combined with findings of a patent foramen ovale, this was the likely source of her BAs.


Discussion: While ~90% of BAs result from contiguous spread, they can develop from hematogenous spread, especially in those who are immunocompromised, have congenital heart disease, or have pulmonary AVMs. In patients with BAs without a local source of infection, evaluation for the above conditions is warranted along with multidisciplinary discussion.

Management challenges include use of seizure prophylaxis with persistent encephalopathy/extensive disease and adjunct therapies for ICH.