Related Experiment Videos
MRI in acute disseminated encephalomyelitis following Semple antirabies vaccine
1Department of Neurology, Nizam's Institute of Medical Sciences, Panjagutta, Hyderabad, India.
Abstract:
I reviewed MRI findings in five patients with acute disseminated encephalomyelitis following vaccination with Semple antirabies vaccine. MRI in two patients with encephalitis features showed multiple white matter lesions in the cerebrum, cerebellar peduncles and brain stem. Two patients who had features of cord involvement showed signal alterations in the cord extending over a few segments. Asymptomatic lesions in the cerebrum were seen in two patients. In a patient with encephalomyelitis MRI 50 days later showed resolution of the lesions. The white matter lesions described were indistinguishable from those seen in acute disseminated encephalomyelitis following other infections.
Insights
Magnetic resonance imaging (MRI) revealed white matter lesions in patients vaccinated with Semple antirabies vaccine, similar to those seen in acute disseminated encephalomyelitis from other infections.
Area of Science:
- Neurology
- Radiology
- Vaccinology
Background:
- Acute disseminated encephalomyelitis (ADEM) is a rare neurological complication that can occur after vaccination.
- The Semple antirabies vaccine is an older, nerve tissue-based vaccine used for rabies prevention.
Purpose of the Study:
- To investigate and describe the magnetic resonance imaging (MRI) findings in patients who developed acute disseminated encephalomyelitis (ADEM) after receiving the Semple antirabies vaccine.
- To compare these MRI findings with those typically observed in ADEM associated with other infections.
Main Methods:
- Retrospective review of MRI scans from five patients diagnosed with ADEM post-Semple antirabies vaccination.
- Analysis of lesion location and characteristics, including the brain parenchyma and spinal cord.
Main Results:
- Multiple white matter lesions were observed in the cerebrum, cerebellar peduncles, and brainstem in patients with encephalitis features.
- Signal alterations in the spinal cord, spanning several segments, were noted in two patients with cord involvement.
- Asymptomatic cerebral white matter lesions were present in two patients.
- In one case, follow-up MRI after 50 days demonstrated resolution of the lesions.
- The observed white matter lesions were indistinguishable from those seen in ADEM following other infectious causes.
Conclusions:
- MRI findings in ADEM following Semple antirabies vaccination are consistent with those seen in ADEM from other etiologies.
- The study highlights the potential for demyelinating complications after Semple vaccine administration.
- These findings underscore the importance of considering vaccination history in the differential diagnosis of ADEM.