Is Takayasu arteritis the result of a Mycobacterium tuberculosis infection? The use of TNF inhibitors may be the proof-of-concept to demonstrate that this association is epiphenomenal.

Abstract

Although the association between Takayasu arteritis (TA) and latent or active Mycobacterium tuberculosis infection has been suggested for a long time, studies conducted in recent years are challenging this notion. Until recently, the possibility of a pathogenic relationship between TA and tuberculosis (TB) was considered a medical curiosity, but the advent of tumor necrosis factor (TNF) inhibitors as therapy for recalcitrant TA cases, as well as the widespread use of Bacille Calmette-Guérin (BCG) for vaccination purposes, has relocated this association as a top priority issue. In an attempt to define whether both diseases are pathogenically linked or if their association is only epiphenomenal in nature, we conduct a thorough literature search on the development of TB in patients with TA receiving TNF inhibitors. From a total of 13 studies that included 214 patients, the occurrence of TB was observed only in two individuals exposed to infliximab. This frequency of 0.93% is similar to that encountered in patients with other rheumatic diseases exposed to TNF inhibitors. Finally, we propose a novel pathogenic model that could reconcile the epidemiological, clinical, and immunological evidence that links TA and TB, while providing rationality for the use of TNF inhibitors in patients with TA.