Central nervous system, spinal root ganglion and brachial plexus involvement in leprosy: A prospective study

Background: Leprosy is primarily a disease of peripheral nerves. Some isolated case reports and case series have communicated imaging changes in the central nervous system (CNS) and brachial plexus in patients with leprosy. Objectives To study the neuroimaging abnormalities in patients with lepra bacilli-positive neuropathy in the context of CNS, spinal root ganglion, and brachial plexus.

Design: Prospective observational study Methods We screened newly-diagnosed patients with multibacillary leprosy presenting with neuropathy. Patients with bacilli-positive sural nerve biopsies were included in the study and subjected to magnetic resonance imaging (MRI) of the brain and spinal cord.

Results: A total of 54 patients with bacteriologically confirmed multibacillary leprosy were screened; Mycobacterium leprae was demonstrated in the sural nerve biopsies of 29 patients. Five patients (5/29; 17.24%) had MRI abnormalities in CNS, spinal root ganglion, and/or brachial plexus. Three patients had MRI changes suggestive of either myelitis or ganglionitis. One patient had T2/FLAIR hyperintensity in the middle cerebellar peduncle while 1 had T2/FLAIR hyperintensity in the brachial plexus.

Conclusion: CNS, spinal root ganglion, and brachial plexus are involved in patients with leprous neuropathy. Immunological reaction against M leprae antigen might be a plausible pathogenetic mechanism for brachial plexus and CNS imaging abnormalities.