Objective: To study whether the analysis of synovial fluid (SF) inflammatory cells can be used for the estimation of the grade of inflammation in the synovium and, therefore, for the prediction of the possible development of joint destruction in spondylarthropathy.

Methods: Forty-one patients with spondylarthropathy and hydropsy in a knee joint were studied. The cellular composition of SF aspirates was investigated and the grade of inflammation in synovial biopsy samples was evaluated by analyzing histological needle biopsy specimens.

Results: The count of SF polymorphonuclear leukocytes (PMN) reflected significantly the activity of acute inflammation. None of the SF cells reflected the chronic inflammation in the synovium.

Conclusion: The number of SF PMNs may reflect the severity of acute inflammatory process in the synovium in patients with spodylarthropathy at a given moment, but the analysis of SF aspirates may not be of use in estimating the activity of chronic phase of inflammation presumably causing the joint destruction.