Objective: The present study aimed to explore the clinical value of serum amyloid A (SAA) in the diagnosis, treatment, and assessment of ankylosing spondylitis (AS).
Methods: Seventy-eight patients with AS were enrolled as the case group, while the control group consisted of 80 healthy individuals enrolled during the same time period. According to the criteria of the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), patients in the case group were divided into those in the remission phase (36 patients) and those in the active phase (42 patients). Levels of SAA, C-reactive protein (CRP), and erythrocyte sedimentation rate (ESR) were measured in all enrolled subjects and analyzed.
Results: SAA levels were significantly higher in the AS group (39.65 ± 12.32 ng/mL) than in the control group (7.64 ± 1.32 ng/mL) (p =0.011) and in patients in the active phase (56.18 ± 17.25 ng/mL) compared with those in the remission phase (20.36 ± 5.36 ng/mL) (p =0.015). The sensitivity and specificity of SAA were 79.49% and 77.50%, respectively. There was a positive correlation between SAA level and the BASDAI grade (r = 0.77, p =0.005), CRP level (r = 0.68, p =0.011), and ESR (r = 0.62, p =0.012).
Conclusion: Not only is SAA a reliable indicator for the presence of AS, it may also be useful for monitoring the activity of this disease.
Keywords: ankylosing spondylitis, serum amyloid A, C-reactive protein, erythrocyte sedimentation rate, disease activity