Diphtheric encephalitis and brain neuroimaging features.

Area of Science:

• Neurology
• Infectious Diseases
• Pediatrics

Background:

• Diphtheria, a vaccine-preventable disease, can lead to severe neurological complications.
• Encephalitis is a rare but serious manifestation of diphtheria, particularly in unvaccinated children.

Observation:

• A 6-year-old unvaccinated boy presented with seizures, fever, and exudative tonsillitis with pseudomembrane, indicative of diphtheria.
• The patient developed progressive encephalopathy and focal neurological deficits, requiring mechanical ventilation.
• Throat swab PCR confirmed diphtheria toxin A and B, and the patient received diphtheria antitoxin.

Findings:

• Brain MRI revealed T2-weighted hyperintensities in the anterior cingulate gyri, insular cortex, and cerebellum.
• These findings represent the first reported MRI characteristics of diphtheric encephalitis.
• Cerebrospinal fluid findings were unremarkable, underscoring the diagnostic utility of MRI.

Implications:

• This case highlights the importance of timely diphtheria vaccination.
• Neuroimaging, particularly MRI, is essential for diagnosing diphtheric encephalitis, especially in atypical presentations.
• The findings contribute to understanding the neuroinvasive potential of diphtheria and guiding clinical management.