Comment on: 'Evaluation of the impact of concomitant fibromyalgia on TNF alpha blockers' effectiveness in axial spondyloarthritis: results of a prospective, multicentre study' by Moltóet al: still a long way to go in the assessment of patients with spondyloarthritis and concomitant fibromyalgia?

We read with great interest the study published by Moltó et al on the impact of concomitant fibromyalgia (FM) on tumor necrosis factor (TNF) alpha blockers’ effectiveness in axial spondyloarthritis (axSpA).1 Indeed, this is a challenging problem in daily practice, especially considering the difficulties in differentiating enthesitis and FM symptoms.2 Therefore, we would like to raise some issues that need clarification in order to better understand the relevance of the study.