Neurosurgical Biopsy and Resection for Diagnosis and Treatment of Balamuthia mandrillaris Amebic Encephalitis, United States

We report a systematic case review of antemortem neurosurgical resections and biopsies and outcomes including new lesions after procedure and survival in Balamuthia mandrillaris granulomatous amebic encephalitis. The investigation was prompted by a 5-year-old patient in the southwestern United States who was treated with nitroxoline, the 2021 Centers for Disease Control and Prevention regimen, and underwent 2 resections; initial resection site recurrence and a new lesion after resection prompted the question whether complete resection versus biopsy is associated with better outcomes. We conducted a literature review and found no substantial difference between neurosurgical resection versus biopsy-only groups. Limitations include case review, number of cases, and incomplete data available. Additional analyses comparing neurosurgical outcomes with outcomes of those diagnosed via blood or cerebrospinal fluid and metagenomic next-generation sequencing might provide more definitive answers. This case and systematic review provide evidence that treatment with nitroxoline and neurosurgical resection could contribute to survival in Balamuthia encephalitis case-patients.