Effects of non-steroidal anti-inflammatory drugs and prednisolone on synovial fluid white cells, prostaglandin E2, leukotriene B4 and cyclic AMP in patients with rheumatoid arthritis

Altogether 53 patients (31 women, 22 men) with definite rheumatoid arthritis were randomly divided into groups of 5-6 patients and treated for one day only with one of the following non-steroidal anti-inflammatory drugs (NSAIDs): acetylsalicylic acid, carprofen, diclofenac, indomethacin, naproxen, proquazone, timegadine, tolfenamic acid or paracetamol, and with prednisolone, in recommended doses. Synovial fluid samples were collected before and after the treatment. White cell count and its differentiation as well as the concentrations of protein, cyclic adenosine-3',5'-monophosphate (cAMP), prostaglandin E2 (PGE2) and leukotriene B4 (LTB4) were measured from the synovial fluid. Synovial fluid leukocyte counts correlated with PGE2 concentrations, but showed no correlation with LTB4 levels before treatment. Significant changes were seen in the form of lowered PGE2 values following treatment with the clinically and experimentally most potent NSAIDs, and as depressed LTB4 levels following prednisolone treatment. The other markers of inflammation are obviously more resistant, changing only slowly during prolonged treatment, and may thus be, at least in part, secondary to the changes in prostanoids.