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Post-transplant acute limbic encephalitis: clinical features and relationship to HHV6
W W Seeley1, F M Marty, T M Holmes
1Department of Neurology, Brigham & Women's Hospital, Boston, MA, USA. wseeley@memory.ucsf.edu
Neurology
|July 11, 2007
Summary
Post-transplant acute limbic encephalitis (PALE) is a distinct syndrome in allogeneic stem cell transplant patients. Human herpesvirus-6 (HHV6) may be associated with PALE, warranting antiviral therapy and seizure control.
Area of Science:
- Neurology
- Infectious Diseases
- Hematology
Background:
- Acute limbic encephalitis is linked to immunosuppression and human herpesvirus-6 (HHV6).
- Clinical and laboratory features of this syndrome remain poorly characterized.
Purpose of the Study:
- To describe the clinical, EEG, MRI, and laboratory features of acute limbic encephalitis post-allogeneic hematopoietic stem cell transplantation (HSCT).
- To investigate the association between HHV6 and this neurological syndrome.
Main Methods:
- Retrospective review of nine patients with acute limbic encephalitis after HSCT.
- Analysis of clinical, EEG, MRI, and CSF HHV6 PCR results.
- Review of CSF HHV6 PCR data from 27 HSCT patients over two years.
Main Results:
- A distinct syndrome of amnesia, SIADH, mild CSF pleocytosis, and temporal EEG abnormalities was observed.
- MRI revealed characteristic limbic system hyperintensities.
- HHV6 PCR was positive in 6/9 patients; positive results were exclusive to PALE patients.
Conclusions:
- Allogeneic HSCT patients are at risk for post-transplant acute limbic encephalitis (PALE), a distinct neurologic syndrome.
- Aggressive seizure control and potential antiviral therapy are treatment considerations.
- While HHV6 is associated with PALE, its pathogenic role requires further investigation.
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