Late Lyme neuroborreliosis encephalomyelitis with distinct MRI features-a case report and systematic literature review.

BACKGROUND

Central nervous system (CNS) Lyme neuroborreliosis (LNB) rarely occurs. Clinical and radiological findings are heterogenous and considered unspecific, often delaying the time to diagnosis and treatment. Recently, specific clinical courses and MRI patterns have been proposed for patients presenting with brainstem encephalitis, but their relevance remains unclear.

OBJECTIVE

To describe radio-clinical features of patients with CNS-LNB encephalomyelitis, and to further investigate potential specific imaging patterns that could facilitate the diagnosis.

METHODS

We report a case of late LNB encephalomyelitis with MRI findings compatible with a recently suggested distinct pattern. We provide a systematic review conducted using Embase and PubMed databases. The clinical, radiological and CSF features, as well as treatment outcome are reported.

RESULTS

Thirty-six cases of confirmed LNB encephalomyelitis were analyzed. The median time to diagnosis was 3 months. One third of patients had a history of tick bite. Common symptoms and signs included gait disorder (74%), headache (71%), fatigue (48%), muscle wasting (48%), and brainstem signs (45%). Common MRI findings were symmetric pontomesencephalic lesions (56%) with patterns compatible with Tarsier-sign (19%) and/or M-sign (33%), and leptomeningeal basal and/or perimedullary enhancement (31%). Twenty-eight percent of the patients recovered completely after treatment, while the remaining had mild neurological deficits (mRS 1-2).

CONCLUSIONS

Leptomeningeal basal and perimedullary enhancement, along with pontomesencephalic symmetric lesions-sometimes compatible with Tarsier-sign and M-sign-could serve as potential MRI markers suggestive of CNS late LNB encephalomyelitis, aiding in earlier diagnosis and treatment.