Blood test to detect early-stage arthritis developed

Patients could soon be diagnosed with early-stage arthritis several years before the onset of physical and irreversible symptoms, thanks to a new test developed by researchers at the University of Warwick in Britain. The test can provide an early diagnosis of osteoarthritis (OA) and also distinguish this from early-stage rheumatoid arthritis (RA) and other self-resolving inflammatory joint disease.

"For the first time we measured small fragments from damaged proteins that leak from the joint into blood," said lead researcher Naila Rabbani of Warwick Medical School. The test, which could be available to patients within two years, identifies the chemical signatures found in the plasma of blood joint proteins damaged by oxidation, nitration and glycation; the modification of proteins with oxygen, nitrogen and sugar molecules.

"The combination of changes in oxidised, nitrated and sugar-modified amino acids in blood enabled early stage detection and classification of arthritis - osteoarthritis, rheumatoid arthritis or other self-resolving inflammatory joint disease," Rabbani noted. By diagnosing which type of arthritis a patient will develop at an early-stage will allow for appropriate treatment that will provide the best chance for effective treatment and potential prevention, the researchers said.

Patients with early-stage and advanced OA, RA or other inflammatory joint disease were recruited for the study alongside a control group of those with good skeletal health. The researchers analysed plasma and synovial fluid samples from both groups. Through their analysis, published in the journal Arthritis Research and Therapy, the researchers detected damaged proteins in characteristic patterns in the samples of those patients with early and advanced OA and RA.

These damages proteins were found at markedly lower levels in the samples of those in the control group -- providing the researchers with the identifiable biomarkers necessary for early detection and diagnosis.