Background Persistent synovitis in one joint is a common clinical problem that could be debilitating and lead to joint destruction in otherwise stable patients with inflammatory arthritis on systemic immunosuppressive treatment. Usual local therapies such as intra-articular steroids are not always effective. In such cases the prospect of intra-articular anti-TNF treatment seems more practical, at lower cost and at less risk than other routes of delivery of these drugs (IV or sc).
Objectives To determine whether intra-articular Etanercept injections provide additional benefit in persistent synovitis in a single joint that was resistant to two corticosteroid injections in otherwise stable psoriatic arthritis patients on Metotrexate treatment.
Methods Five Psoriatic arthritis patients each of them with one persistently active joint despite systemic Metotrexate treatment (mean dose 20 mg per week), and two successive intra-articular Betamethasone injections ten days apart were injected with 50 mg of Etanercept intra-articularly. Gray scale and power Doppler ultrasound was performed at baseline and two months after the procedure. In addition patients' reported pain and stiffness, as well as pain and swelling on joint palpation were measured and routine laboratory parameters were collected at baseline, in one week and then monthly up to the fifth month after the intervention.
Results In total five joints (three knee and two wrist joints) were injected with 50 mg of Etanercept without Lidocain. This was performed at least one month after the last ineffective Betametasone injection in order to avoid possible residual steroid effect. At baseline all patients had pain scores of more than 6 on VAS and considerable subjective stiffness and objective swelling in the affected joint. Laboratory parameters were normal except slightly elevated CRP (9.2 and 10.1 mg/l) and ESR (31 and 33 mm/h) in two of the patients. Grey scale US showed marked synovial thickness – grade IV in one patient, grade III in three and grade II in one, while all five active joints exhibited grade II synovitis on power Doppler scanning. In one week there was no change either in the patients' complaints, or in the physical examination and laboratory parameters. In contrast in one month there was marked relief in patients' reported pain and stiffness – four of the patients reported no pain, while one had only mild pain (VAS bellow 3). On physical examination there was no pain or joint swelling in three of the patients, one patient had mild swelling but no pain, and the remaining one had mild pain and swelling. These findings persisted at the monthly visits up to the fifth month. Laboratory parameters were normal in one month and remained so till the end of the study period, no adverse findings were noted in CBC or liver enzymes. At the second month sonography showed improvement in gray scale synovitis – two patients had grade I, and three patients – grade II, while neither of the joints injected with Etanercept exhibited any power Doppler signal at this examination – PD grade 0.
Conclusions Intra-articular Etanercept could be beneficial in alleviating active monoarthritis that failed steroid injections in otherwise stable Psoriatic arthritis patients. There was also a reduction in the abnormal gray scale and power Doppler ultrasound findings. No adverse effects were noted.
Disclosure of Interest None declared