Validated sonographic enthesitis instruments in PsA lacking
Only a few sonographic enthesitis scoring instruments developed for spondyloarthritis (SpA) have been validated in psoriatic arthritis (PsA), and none of them passed the Outcome Measures in Rheumatology (OMERACT) filter in patients with PsA, according to a systematic review.
Of the 310 identified manuscripts, 51 were included. There was only one scoring instrument of enthesitis that was specifically developed and validated in patients with PsA.
Eighteen (35 percent) studies included patients with PsA, while others focused on SpA. In PsA, biomarkers and clinical examination were used to assess construct validity in one (2 percent) and 11 (21.5 percent) of the studies, respectively; none of the studies used imaging for the same purpose.
Of the studies, only two (4 percent) evaluated discriminative validity in PsA. Seven studies assessed responsiveness to treatment, none of which included patients with PsA.
“Additional research is required before endorsing a specific instrument for the assessment of enthesitis in patients with PsA,” the authors said.
As part of the Group for Research and Assessment of Psoriasis and Psoriatic Arthritis (GRAPPA) ultrasound working group, the authors searched PubMed, Embase and Cochrane databases for original publications containing terms related to ultrasound, enthesitis, SpA or PsA.
Data extraction focused on the properties of the sonographic enthesitis instruments used in each study following components of the OMERACT filter: feasibility, test-retest reliability, construct validity as related to clinical assessment of enthesitis, biomarkers of inflammation and imaging of enthesitis by other modalities, discriminative validity, and responsiveness to treatment.