To the Editor:

We thank Dr. Drosos for his commentary on our study evaluating the clinical response of intraarticular INF compared with intraarticular corticosteroids. We included 23 patients with undifferentiated arthritis, RA, psoriatic arthritis, SpA, and chronic juvenile arthritis, who had previously received ≥1 intraarticular therapeutic injection. As previously mentioned, we excluded patients with pseudogout, osteoarthritis, and septic arthritis. Similar to previously reported cases with good clinical response (1–4), we used fixed dose (100 mg) of intraarticular INF. Also, we followed the basic assumption that the administration of INF (100 mg) into the knee joint should result in a therapeutic range compared with the effective dose of intravenous therapy.

As reported by Nikas et al (5), it is possible that 2 consecutive injections with infliximab (100 mg each) would have led to more success, but our study was not designed to incorporate a dose-finding strategy. We agree that it could be interesting to investigate with ultrasound or MRI whether any objective changes occur after intraarticular injection with INF or corticosteroids. However, even if changes and possible differences would have been present, the fact remains that intraarticular INF was not superior to intraarticular MP, as measured by clinical responses (defined as event-free survival and/or no improvement of knee joint score evaluated by a trained nurse). If we want to give better and longer symptom relief to our patients with these chronic types of gonarthritis, we need to look for other therapies.

  • 1
    Bokarewa M, Tarkowski A. Local infusion of infliximab for the treatment of acute joint inflammation [letter]. Ann Rheum Dis 2003; 62: 7834.
  • 2
    Dreher R, Flaig W, Leitzke D. Treatment of rheumatoid arthritis by intra-articular injections with TNFα blockers [abstract]. Arthritis Rheum 2001; 44: S42.
  • 3
    Conti F, Priori R, Chimenti MS, Coari G, Annovazzi A, Valesini G, et al. Successful treatment with intraarticular infliximab for resistant knee monarthritis in a patient with spondylarthropathy: a role for scintigraphy with 99mTc-infliximab. Arthritis Rheum 2005; 52: 12246.
  • 4
    Schatteman L, Gyselbrecht L, de Clercq L, Mielants H. Treatment of refractory inflammatory monoarthritis in ankylosing spondylitis by intraarticular injection of infliximab. J Rheumatol 2006; 33: 825.
  • 5
    Nikas SN, Temekonidis TI, Zikou AK, Argyropoulou MI, Efremidis S, Drosos AA. Treatment of resistant rheumatoid arthritis by intra-articular infliximab injections: a pilot study [letter]. Ann Rheum Dis 2004; 63: 1023.

A. E. van der Bijl MD*, C. F. Allaart MD, PhD*, * Leiden University Medical Center Leiden, The Netherlands.