Background Musculoskeletal ultrasound (US) is a reliable imaging tool, which complements clinical assessment of rheumatic conditions and can be used to guide a variety of interventions1. US-guided synovial biopsy (UGSB) is a minimally invasive, safe and well-tolerated procedure2 which facilitates the retrieval of synovial tissue for basic research and early phase drug development studies.
Objectives To determine the impact of an USGB on the US assessment of wrist joints in RA patients prior to initiation of first-line anti-TNFα therapy.
Methods At baseline all patients underwent an US assessment (Logiq9®, GE Healthcare) of both wrists followed by a unilateral UGSB (Quick-Core®, Cook Medical). US was repeated on their next visit prior to anti-TNFα administration. US scans were scored for synovial thickness (ST) and Power Doppler (PD) on a 0-3 scale for the radial, midline, and ulnar longitudinal views. Both mean scores for each wrist and the view with the maximum ST and PD score were used for analysis. The contralateral wrist was used as a control and compared to the biopsied wrist in the analysis. T-test was used to compare US measures before and after biopsy and a mixed effects model was used to assess the interaction between wrist scores.
Results Twenty-nine patients (females 79%, age 57.2[25-85] years, disease duration 6.1[1-25] years, RF positive 58%, anti-CCP positive 66%, DAS28 6.29[5.1-8]) were enrolled. Mean time between the two US scans was 14.7 (8-28) days.
As expected, the control wrist had lower mean ST and PD scores (p<0.001) before and after the biopsy. US assessment of the biopsied wrist pre- and post-UGSB demonstrated no significant difference in either mean ST (p=0.57) or PD (p=0.12). In addition, the interaction between both wrists US scores did not change post-procedure and this was demonstrated for both mean ST (p=0.22) and PD (p=0.76) (figure 1). Similar results were demonstrated when using the maximum ST and PD scores from each wrist with no significant difference detected before and after the procedure.
DAS28, tender and swollen joint count, patient global, ESR, and CRP did not show any significant change post-UGSB.
Conclusions In this RA population of DMARD failures, UGSB of the wrist did not significantly alter subsequent clinical or US assessments. This would imply that it is reasonable to incorporate a biopsied wrist joint in an US dataset or clinical outcome tools such as the DAS28 without prejudice.
D'Agostino MA, Schmidt WA. Ultrasound-guided injections in rheumatology: actual knowledge on efficacy and procedures. Best practice & research. Clinical rheumatology 2013;27(2):283-94
Kelly S, Humby F, Filer A, Ng N, Di Cicco M, Hands RE, et al. Ultrasound-guided synovial biopsy: a safe, well-tolerated and reliable technique for obtaining high-quality synovial tissue from both large and small joints in early arthritis patients. Annals of the rheumatic diseases 2013.
Acknowledgements The authors thank Mmes Victoria Katsande, Celia Breston, and Audrey Davidson for their assistance in collecting the data.
Disclosure of Interest None declared