Laboratory examination characteristics of rhyming rheumatism

During the acute attack period of ated rheumatism, laboratory examination can find that ESR and various acute phase factors such as C-reactive protein and procalcitonin are obviously increased, but they can return to normal levels during the attack period. about 1/3 patients are rheumatoid factor positive, a few patients are HLA-DR4 positive, but ANA is negative, complement level is normal, white blood cell count in joint synovial fluid is increased during the attack period, synovial biopsy shows neutrophils, Inflammatory cell infiltration and fibrocytosis.