Scrub typhus-associated acute disseminated encephalomyelitis

Area of Science:

• Neurology
• Infectious Diseases
• Demyelinating Diseases

Background:

• Acute disseminated encephalomyelitis (ADEM) is a rare, monophasic inflammatory demyelinating disease of the central nervous system.
• ADEM typically follows infections or vaccinations, but its association with specific pathogens like scrub typhus remains underexplored.

Observation:

• A 77-year-old male presented with fever, seizures, and altered consciousness, indicative of a severe neurological event.
• Neurological examination revealed stupor, nuchal rigidity, and left hemiparesis, with observed generalized tonic-clonic seizures.
• Diagnostic workup confirmed scrub typhus infection through positive anti-Orientia tsutsugamushi antibodies in serum and cerebrospinal fluid.

Findings:

• Cranial MRI showed progressive, extensive white matter hyperintensities, predominantly in the periventricular regions, characteristic of demyelination.
• Despite initial treatment with minocycline and subsequent high-dose corticosteroids, the patient experienced only limited clinical improvement, suggesting a complex disease course.
• This case represents the first documented instance of ADEM occurring in temporal association with scrub typhus as the sole identified trigger.

Implications:

• This finding expands the spectrum of neurological complications associated with scrub typhus.
• Highlights the importance of considering scrub typhus in the differential diagnosis of ADEM, particularly in endemic areas.
• Suggests potential challenges in managing ADEM secondary to scrub typhus, necessitating further research into optimal treatment strategies.