The results of purified protein derivative test in ankylosing spondylitis patients: clinical features, HRCT results and relationship with TNF-blocker usage

In this study, we evaluated the clinical features, treatment modalities, including TNF-blockers, purified protein derivative (PPD) test, chest X-ray and HRCT results in our AS patients. We evaluated the clinical features, disease activity and PPD results in 88 AS patients (72 males, 16 females, mean age: 38.3 ± 10) diagnosed at our center. 119 RA, 28 SLE and 27 gouty arthritis patients followed up at the same time period were taken as the control group. The mean disease duration in AS patients was 12.6 ± 8.3 years. The frequency of PPD positivity in AS patients (77.3%) was similar to that in gouty arthritis (70.4%) patients; and significantly higher than the frequency in SLE (21.4%) and RA (35.3%) patients ( P values