Positron emission tomography in juvenile Alexander disease

Area of Science:

• Neurology
• Neurodegenerative Diseases
• Medical Imaging

Background:

• Juvenile Alexander disease is a rare, fatal leukodystrophy.
• Cervical kyphosis can be an early sign.
• Diagnosis relies on clinical, imaging, and biochemical markers.

Observation:

• A 13-year-old male presented with cervical kyphosis and was evaluated for neurological disorders.
• Cerebrospinal fluid analysis revealed elevated levels of alphaB-crystallin and heat shock protein 27.
• Magnetic resonance imaging (MRI) indicated characteristic leukodystrophy in the brain's white matter.

Findings:

• The patient was diagnosed with juvenile Alexander disease based on clinical presentation, MRI findings, and biomarker elevation.
• Positron emission tomography (PET) using 18F-fluorodeoxyglucose (FDG) demonstrated hypometabolism in the frontal white matter.
• Crucially, the adjacent gray matter exhibited normal glucose metabolism, suggesting selective white matter vulnerability.

Implications:

• This case highlights the utility of combining MRI, cerebrospinal fluid biomarkers, and FDG-PET for diagnosing juvenile Alexander disease.
• The preserved gray matter metabolism despite white matter involvement offers insights into the disease's pathophysiology.
• Further research into the selective vulnerability of white matter in Alexander disease is warranted.