Synovial fluid lactate determinations as a diagnostic aid in cases of monoarticular arthritis

The concentration of synovial fluid lactate was determined by an enzymatic kit method in 16 patients with various types of monoarticular arthritis and in 2 patients with non-inflammatory lesions and no joint effusion. Lactate concentrations in control cases were 1.2 mmol/l, in septic arthritis above 10 mmol/l, in pseudogout and yersinia arthritis around 7 mmol/l, and in other cases of inflammatory, nonseptic arthritis around 3.0 mmol/l.