Occurrence of amyotrophic lateral sclerosis during TNF inhibitor treatment in inflammatory rheumatic disease. What are the relationships?

<h2>ABSTRACT</h2> Neurological adverse events have been reported in patients receiving tumor necrosis factor inhibitors (TNFi) for the treatment of inflammatory rheumatic diseases. The occurrence of amyotrophic lateral sclerosis (ALS) during TNFi therapy is rare but raises the question of a possible relationship. We report 2 cases of ALS diagnosed during TNFi treatment: the first in a patient with spondyloarthritis treated with adalimumab and the second in a patient with seronegative polyarthritis treated with infliximab. Tumor necrosis factor alpha (TNFα) has been implicated in ALS pathogenesis and is considered to exert both neuroprotective and neurotoxic effects, depending on the differential expression of its receptors in distinct regions of the central nervous system. We also review data from pharmacovigilance databases and discuss the potential influence of TNFα inhibition on ALS development.