Synovial fluid analysis with leukocyte esterase reagent strip test.

To determine whether leukocyte esterase reagent strip test (LERST) analysis could help distinguish inflammatory arthritis from mechanical joint effusion. We analyzed synovial fluid (SF) from consecutive patients with a non-traumatic joint effusion during a 6-month period. Inflammatory SF was defined by white blood cell (WBC) count ≥ 2000/mm.