Prevalence of Latent Tuberculosis (LTB) among Household Contacts of Newly Diagnosed Omani Pulmonary Tuberculosis Patients

• 作者: Esklid Peterson Fatma Al Ajmi Jeffrey Singh Lamiya Balushi Nada Mahrazi Olivier Koole Padmamohan Kurup
• 来源期刊: 结核病研究(英文)
• 学科: 医学
• 关键词: LATENT TB Infection INTERFERON GAMMA Release ASSAY TUBERCULIN Skin Test Cavitary LESIONS
• 年，卷（期）: 2020,（1）
• 页码范围: 11-21
• 页数: 11页
• 分类号: R52

摘要

Background: Oman is a high-income, low prevalent country for tuberculosis disease. Although the rates have remained static over the last decade, the country is aiming for Tuberculosis (TB) elimination. Household contacts of pulmonary TB (PTB) patients form a high-risk group of susceptible individuals who could remain reservoirs of active disease. Objective: A retrospective study was conducted to estimate the prevalence of latent TB infection by Tuberculin Skin Test (TST) or Interferon-Gamma Release Assay (IGRA) screening tests among the household contacts of Omani patients with pulmonary tuberculosis. Design: A cross-sectional survey conducted between 2017 and 2018 of TB cases and their contacts in Muscat Governorate, Oman. Results: Out of the 278 contacts identified, 188 contacts fulfilled the inclusion criteria and were enrolled into the study. The prevalence of Latent Tuberculosis Infection (LTBI) was 22.8% (95% CI: 17.0 - 29.5) among household contacts. We found higher proportions of LTBI among females than males (28.7% vs. 15%, p = 0.027). Those who were exposed to Acid Fast Bacilli (AFB) smear positive cases were more likely to be LTBI (28.7% versus 15% in smear negative cases;p = 0.047). We also found an increasing trend of infection (32.3%) in the oldest age group (46 - 80 years). Conclusion: Besides children, female household contacts and older age contacts should be prioritized for screening as they are more likely to be infected and develop active disease.