Dados do Trabalho

Title

MULTIFOCAL MOTOR NEUROPATHY IN A PATIENT WITH RHEUMATOID ARTHRITIS NOT USING TNF-BLOCKER.

Background

Noncompressive peripheral neuropathy, usually due to epi or peurineurial vasculitis, is not a rare extraarticular manifestation of rheumatoid arthritis (RA). The occurrence of peripheral neuropathies in RA patients has gained recent interest after the advent of tumor necrosis factor (TNF) blockers in therapeutics. Multifocal motor neuropathy (MMN) is an inflammatory condition defined by limb weakness and motor-conduction block in the electrophysiological study. The association of RA with MMN is rather enigmatic, and TNF blockers work usually as triggers. We herein describe an interesting coexistence of RA and MMN in a patient with no previous exposure to anti-TNF agents.

Case report

The patient, a 60-year-old housewife, was diagnosed seropositive RA ten years ago. Over this period of time, she has been taking methotrexate 15 mg weekly and low-dose prednisone. She recently came to our outpatient clinic ago due to weakness in the lower limbs for the last year. Deep reflexes were diminished. C-reactive protein levels were normal. Protein electrophoresis was umremarkable. Nerve conduction studies revealed multifocal, persistent, partial conduction blocks on motor nerves, findings fully compatible with MMN. The patient has been additionally treated with high-dose intravenous immunoglobulin (IVIG) for the last six months, with partial response.

Conclusion

Considering the Pubmed database, the current is probably the first report of MMN in a RA patient not exposed to an anti-TNF agent. Of interest, the patient showed inactive RA when MMN firstly appeared. Unexpectedly, the neuropathy was little responsive to IVIG. If such association is only coincidental, or if MMN represents a RA-associated neuropathy, it has to be clarified in further studies.