Fungal brain abscess caused by azole-resistant cellulolytic yeast in an immunocompetent patient: case report and literature review

Abstract

Introduction: Brain abscess is a rare infection, which in healthy patients is usually caused by bacteria, and in immunocompromised individuals, by fungi and protozoa. The latter group is often treated with azoles. Abscesses caused by azole-resistant yeast in immunocompetent patients are particularly uncommon and challenging. Objective: To describe a rare case of brain abscess caused by fluconazole-resistant yeast in an immunocompetent patient and to discuss pathogenesis, diagnosis, and treatment based on a literature review. Methods: Clinical and laboratory data were collected through medical reports, copies of medical records, and interviews provided by the patient. Results: A young patient, previously healthy and immunocompetent, initially presented with a headache and subsequently deteriorated clinically. Magnetic resonance imaging revealed an encapsulated nodular image with homogeneous enhancement limited to the capsule, regular contours, thick content, and voluminous surrounding edema. After neurosurgical intervention to resect the lesion, a brain abscess caused by cellulolytic yeast resistant to fluconazole and sensitive to amphotericin B was diagnosed. Unusual differential diagnosis of brain tumors and uncommon pathogenesis and resistance hindered early and assertive treatment. Conclusion: It’s essential to make an early diagnosis of brain abscesses in patients with acute neurological symptoms and focal lesions on cranial imaging exams. Additionally, early antimicrobial treatment is crucial, even when facing other differential diagnoses, and consideration should be given to the possibility of unusual etiological agents, such as resistant fungi.