A Novel Study of Validity of Latent Tuberculosis as a Predictor to Tuberculosis of Thoracic Spine

Abstract

Objective: The objective of this study is to assess the validity of latent tuberculosis (TB) as a predictor for TB of thoracic spine.Methods: This cross-sectional study involved 31 patients with osteoarticular TB diagnosed on the base of clinical features, magnetic resonance imaging, and tissue biopsy. Patients’ demographic and clinical characteristics of the disease were recorded. Latent TB was diagnosed by tuberculin skin test (TST) >10 mm. Results: The mean age of patients was 44.9 ± 19.0 years. Females were 17 (54.8) and mean body mass index was 24.6 ± 4.9 kg/m2. Thoracic spine was the highest osteoarticular TB site. Then, lumbar spine TB was 3 (9.7%) patients. Third in rank was TB of the knee joints 2 (6.5%). Cervical spine and hip joint TB were each one, 1 (3.2) patients, respectively. Validity of latent TB as a test to predict TB of thoracic spine revealed that if TST was positive, then this test will be accurate in 77.42% and we can establish the diagnosis of TB of the thoracic spine with 90.48% confidence if we had a clinical suspicion of TB of thoracic spine.Conclusion: There was a significant positive correlation between osteoarticular TB and latent TB. Thoracic spine TB was the most common osteoarticular TB infection compared to other sites. Patients who had latent TB have 9.5 times risk of having TB of the thoracic spine. Latent TB was a valid measure to predict TB of thoracic spine.