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Updated: Jul 23, 2025
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Dynamic Visual Tests to Identify and Quantify Visual Damage and Repair Following Demyelination in Optic Neuritis Patients
Published on: April 14, 2014
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Occipital Nocardia Abscess Presenting With Positive Visual Phenomenon and Quadrantanopsia
Alexander S Fein1, Sean M Kelly, Eddie Louie
1Department of Neurology (ASF, SMK, SLG, SNG), New York University Grossman School of Medicine, New York, New York; Division of Infectious Diseases (EL), Department of Medicine, New York University Grossman School of Medicine, New York, New York; and Departments of Radiology (MGY, RJ) and Department of Pathology (CMW), New York University Grossman School of Medicine, New York, New York.
Summary
A rare Nocardia farcinica brain infection caused visual disturbances and a visual field defect in an immunocompromised patient. Prompt diagnosis and treatment led to complete resolution of neurological symptoms.
Area of Science:
- Neurology
- Infectious Disease
- Ophthalmology
Background:
- A 74-year-old male with significant comorbidities including chronic obstructive pulmonary disease, glaucoma, and Stage IIIB squamous cell lung cancer presented with visual disturbances.
- The patient reported transient flashing lights in his right visual hemifield, followed by a persistent right visual field defect.
Observation:
- Clinical examination revealed a right homonymous hemianopsia, most pronounced inferiorly.
- Initial neuroimaging (CT scan) suggested an acute stroke in the left occipital lobe.
- Electroencephalogram (EEG) monitoring detected left posterior quadrant seizures correlated with the visual phenomena.
Findings:
- Magnetic Resonance Imaging (MRI) demonstrated centrally necrotic, peripherally enhancing mass lesions in the brain.
- Biopsy and Gram stain identified Nocardia farcinica, a gram-positive beaded rod, as the causative agent.
- The patient received a six-week course of intravenous meropenem and a year of oral trimethoprim-sulfamethoxazole.
Implications:
- This case highlights the importance of considering infectious etiologies, such as Nocardia brain abscess, in patients presenting with stroke-like symptoms and visual field defects.
- Early and accurate diagnosis through advanced neuroimaging and microbiological analysis is crucial for effective treatment.
- Successful treatment with antibiotics resulted in complete resolution of the visual field deficit, underscoring the treatable nature of Nocardia brain infections.
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