Prevalence of latent TB infection in HIV infected persons in the Sylvanus Olympio teaching hospital of Lomé

Abstract

Objective: Determine the prevalence of latent TB infection in HIV-infected people. Method: Using a cross-sectional study on HIV-infected persons monitored in the Department of Lung and Infectious Diseases of CHU Sylvanus Olympio of Lomé from August 10, 2010 to November 10, 2010. All patients are receiving anti-retroviral therapy and have no clinical or radiological symptoms of TB, and had never received tuberculin skin test (TST) in the last 3 months. The CD4 rate of all patients was more than 200cells/ μl. The diagnosis of latent TB infection is based on the measurement of at least 5 mm of skin induration, 72 h after a subcutaneous injection of 5IU of purified tuberculin. Results: One hundred and fifty four persons were included in the study, of which 107 were female and 47 were male. The median age was 40 years old. Eleven patients were exposed to a risk of TB and only 70.7% of patients had a BCG scar. A suspicion of former TB was found in 18.8% of patients and approximately 45% of patients were very immunocompromised with a CD4 rate between 200 and 350; 117 patients had a positive TST. This represents an overall prevalence of 76% of latent TB infection. Conclusion: The prevalence of latent TB infection obtained with the TST is high in this study. A similar study using the interferon-gamma release assay, which is more specific, would be more helpful to obtain more reliable epidemiological data on patient outcomes and to determine the appropriateness of the use of chemoprophylaxis with isoniazid.

Keywords

• Prevalence
• Latent TB infection
• HIV