Background. Ankylosing Spondylitis (AS) is a chronic systemic inflammatory rheumatic disease that primarily affects the axial skeleton and leads to limitation of spinal mobility. Acute anterior uveitis is the most common extraspinal lesion of AS occurring in the course of the disease. Uveitis can lead to serious complications that can compromise the visual function. Because of recent promising data concerning the effects of anti tumor necrosis factor (TNF) therapy not only on AS but also on refractory uveitis it is important to determine the uveitis baseline prevalence and characteristics related also with clinical and biological markers. Aims. The aims of the study were to evaluate the prevalence of uveitis and to establish several associations with clinical and paraclinical parameters in Romanian patients with AS. Design. A retrospective clinical study was carried out on a group of 104 patients diagnosed with AS and admitted to "Sf Maria" Clinical Hospital between January and December 2007. Methods. The following parameters were taken out of the patients' files: demographic data, duration of the disease, axial and/or peripheral involvement, the presence of HLA-B27 antigen, inflammation biological markers, followed treatments, activity and functionality scores BASDAI/BASFI, ocular involvement passively reported by the patients and confirmed by ophtalmological exams. Results. The global prevalence of uveitis in patients with AS was 14.42% with a mean disease duration of 9.7 years. Uveitis was associated with uni/bilateral coxitis. The uveitis were predominant HLA B27 positive, unilateral and recurrent. Conclusions. The prevalence and characteristics of uveitis in Romanian patients with AS are comparable to the data in literature. It was demonstrated an association between uveitis and coxitis both of them being features of the disease severity. The similarities and differences in the pat hogenesis of uveitis and arthritis remain a topic for further discussion and research. [ABSTRACT FROM AUTHOR]