Systemic cytokine measurements: their role in monitoring the response to therapy in patients with rheumatoid arthritis.
Luqmani R., Sheeran T., Robinson M., Richardson K., Winkles J., Emery P.
OBJECTIVE: To determine the value of serial measurements of circulating cytokines in patients with rheumatoid arthritis in response to the introduction of disease modifying anti-rheumatic drugs (DMARDs). METHODS: A prospective 12-week study of 98 patients starting second line therapy with serial measurements of IL1 beta, IL2 receptor, IL6, TNF, and urinary neopterins as well as ESR, CRP and rheumatoid factor. RESULTS: The markers of the acute phase response fell significantly with treatment as did the rheumatoid factor. IL-6 fell in certain sub-groups (significantly so after sulphasalazine SZP) of treated patients, but no other consistent change in circulating cytokine levels was demonstrated. Urinary neopterins rose with therapy. CONCLUSIONS: The measurement of circulating cytokine levels in patients with rheumatoid arthritis is of limited benefit; macrophage function (as measured by urinary neopterins) is initially enhanced by DMARDs in patients with rheumatoid arthritis.