Is latent tuberculosis infection challenging in Iranian health care workers? A systematic review and meta-analysis

Abstract

BackgroundThe high chances of getting latent tuberculosis infection (LTBI) among health care workers (HCWs) will an enormous problem in low and upper-middle-income countries.MethodSearch strategies were done through both national and international databases include SID, Barakat knowledge network system, Irandoc, Magiran, Iranian national library, web of science, Scopus, PubMed/MEDLINE, OVID, EMBASE, the Cochrane library, and Google Scholar search engine. The Persian and the English languages were used as the filter in national and international databases, respectively. Medical Subject Headings (MeSH) terms was used to controlling comprehensive vocabulary. The search terms were conducted without time limitation till January 01, 2019.ResultsThe prevalence of LTBI in Iranian’s HCWs, based on the PPD test was 27.13% [CI95%: 18.64–37.7]. The highest prevalence of LTBI in Iranian’s HCWs were estimated 41.4% [CI95%: 25.4–59.5] in the north, and 33.8% [CI95%: 21.1–49.3] in the west. The lowest prevalence of LTBI was evaluated 18.2% [CI95%: 3.4–58.2] in the south of Iran. The prevalence of LTBI in Iranian’s HCWs who had work-experience more than 20 years old were estimated 20.49% [CI95%: 11–34.97]. In the PPD test, the prevalence of LTBI in Iranian’s HCWs who had received the Bacille Calmette–Guérin (BCG) was estimated 15% [CI95%: 3.6–47.73]. While, in the QFT, the prevalence of LTBI in Iranian’s HCWs in non-vaccinated was estimated 25.71% [CI95%: 13.96–42.49].ConclusionsThis meta-analysis shows the highest prevalence of LTBI in Iranian’s HCWs in the north and the west probably due to neighboring countries like Azerbaijan and Iraq, respectively. It seems that Iranian’s HCWs have not received the necessary training to prevent of TB. We also found that BCG was not able to protect Iranian’s HCWs from TB infections, completely.

Investigating Two-stage Tuberculin Skin Test for Screening Latent Tuberculosis Infections in Diabetic Patients: A Regional Study in Khorramabad, Iran

“…Latent tuberculosis infection (LTBI) means exposure to M. tuberculosis without clinical signs and evidence of active tuberculosis in para-clinical examinations, including chest x-rays, sputum cultures, and sputum smears [3]. The bacterium remains inactive in the body and does not cause disease [4]. In these cases, exposure to the causative agent is indicated by the tuberculin skin test (TST) or the level of Interferon-Gamma Release Assay (IGRA) [3][4][5].…”

“…The bacterium remains inactive in the body and does not cause disease [4]. In these cases, exposure to the causative agent is indicated by the tuberculin skin test (TST) or the level of Interferon-Gamma Release Assay (IGRA) [3][4][5].…”

“…The tuberculin test is performed by injecting 0.1 ml of purified protein derivative (PPD) in the upper 2/3 of the forearm with an insulin syringe. After 48-72 h, the induration (swelling) diameter is measured at the injection site [3][4][5][6]. Indurations ≥ 5 mm are considered positive in patients with immunodeficiency and those receiving immunosuppressive drugs [4][5][6].…”

“…After 48-72 h, the induration (swelling) diameter is measured at the injection site [3][4][5][6]. Indurations ≥ 5 mm are considered positive in patients with immunodeficiency and those receiving immunosuppressive drugs [4][5][6]. Indurations ≥ 10 mm are considered positive in patients with type 2 diabetes mellitus and people exposed to Mycobacterium, and indurations ≥ 15 mm are considered positive in all individuals [4][5][6][7].…”

“…Indurations ≥ 5 mm are considered positive in patients with immunodeficiency and those receiving immunosuppressive drugs [4][5][6]. Indurations ≥ 10 mm are considered positive in patients with type 2 diabetes mellitus and people exposed to Mycobacterium, and indurations ≥ 15 mm are considered positive in all individuals [4][5][6][7]. Some people with LTBI have a falsenegative tuberculin skin test.…”