Adherence to National Guidelines for Latent Tuberculosis Infection Screening Among HIV-Infected Patients in Philadelphia

INTRODUCTION: Treatment of latent TB infection (LTBI) in HIV-infected patients reduces the risk of progression from latent to active tuberculosis infection. According to guidelines from the Centers for Disease Control and Prevention, HIV-infected patients should be screened for LTBI at the time of entry into HIV care. We sought to evaluate adherence to LTBI screening guidelines at an urban HIV clinical center.

METHODS: We conducted a retrospective cohort study of all patients entering the Partnership Comprehensive Care Practice (PCCP), the largest HIV treatment facility in the greater Philadelphia region, from January 1, 2010 to December 31, 2010. LTBI screening was performed with a tuberculin skin test (TST), which requires a follow-up visit within 2-3 days for reading the test result. Our objective was to measure adherence to national guidelines for LTBI screening, and identify patient factors associated with a failure to complete LTBI screening within a 1-year period.

RESULTS: Among 272 patients entering the PCCP, 54% (n=147) had no discussion of LTBI status or screening within the medical records during the first 12 months after their initial visit. Only 7% (n=20) had a TST placed and read within one year. Twenty-six patients (10%) had a TST placed within the first year but not read. The average time between the patient’s first visit and addressing LTBI, when addressed, was 66 days (SD, 101 days). In adjusted analyses, we did not identify any clinical or demographic factors that were predictive of failure to complete LTBI screening. 

CONCLUSIONS: Adherence to national LTBI screening guidelines for HIV-infected patients was low. Future work will determine whether a transition from TST-based screening to an interferon-gamma release assay (IGRA), a blood test that can be performed in a single visit, will lead to improved rates of LTBI screening.