The levels of neutrophils oxidative burst in rheumatic disorders.

We investigated the participation of the polymorphonuclear leukocytes (PMNs) as mediators of tissue destruction in 2 variants of rheumatic disorders that affect primarily the joints: the rheumatoid arthritis (RA) and the osteoarthritis (OA). We noted significant differences in the number of PMNs present at the joint level, which was low in OA and high in RA. The unstimulated and in vitro stimulated with opsonized zymozan (OZ) or ConA PMNs from the peripheral blood of these two groups of patients released a normal level of oxygen free radicals (OFR). On the contrary, the neutrophils isolated from the synovial fluid (SF) of RA patients showed a distinct feature: the unstimulated cells released high amounts of OFR, while those in vitro stimulated with OZ or ConA presented a low level of respiratory burst. In OA both in vitro unstimulated and stimulated with OZ or ConA neutrophils isolated from the SF had diminished values of OFR released. We assume that the chemiluminescence assay could detect distinct differences of the PMNs implications in RA and OA injuries and may be a laboratory test in the differential diagnosis of these rheumatic disorders.