TNF Receptor-associated Periodic Syndrome Presenting with Polyneuropathy and CNS Demyelination
Nishika Karbhari1, Nathaniel Robbins2
1Dartmouth-Hitchcock, 2Neurology, Dartmouth-Hitchcock
Background:
TNF receptor-associated periodic syndrome (TRAPS) is an autosomal dominant condition manifesting as periodic exacerbations of systemic inflammation. It is exceedingly rare, with a prevalence of approximately one per one million. Here we report a patient with TRAPS that developed an otherwise unexplained sensory-predominant polyneuropathy and a CNS demyelinating disease that radiographically mimicked multiple sclerosis (MS).
Results:
A 74 year old female with a history of TRAPS (with a classic TNFRSF1A mutation on chromosome 12) presented for autonomic evaluation due to complaints of postural lightheadedness. She had decades of episodic fevers, malaise, and rashes. She had developed bilateral foot numbness a few years prior, with EMG/NCS proven sensory neuropathy. A prior tilt table test suggested delayed orthostatic hypotension, without compensatory tachycardia. Prior MRI brain showed multifocal white matter hyperintensities in a pattern consistent with demyelinating disease, and C-spine MRI showed patchy areas of T2 signal hyperintensity. LP was normal, with 0 unique CSF oligoclonal bands. She never had clinical symptoms of an MS attack. Autonomic testing showed normal vasomotor function, length-dependent sudomotor dysfunction, and normal orthostatic vital signs. Repeat EMG/NCS showed slight progression of sensory-predominant axonal polyneuropathy. Work-up for amyloidosis including serology and skin and fat pad biopsy were negative. Neurologic exam showed sensory ataxia, with a positive Romberg sign (during which her “lightheadedness” was reproduced) and diminished large-fiber sensation. It was concluded that she had both sensory neuropathy and dorsal column dysfunction from her intrinsic cervical demyelinating lesion. Canakinumab was initiated for treatment.
Conclusions:
TRAPS is a rare, multisystem inflammatory condition that can produce CNS white matter lesions that can radiographically mimic multiple sclerosis. In addition, TRAPS may be associated with a peripheral polyneuropathy, though further research is warranted.