Enduring Challenge of Latent Tuberculosis in Older Nursing Home Residents: A Brief Review

Tuberculosis (TB) kills almost 4,000 people a day and is competing with human immunodeficiency virus/acquired immune deficiency syndrome (HIV/AIDS) as the most deadly infectious disease in the world. The gold standards of detection and management of latent tuberculosis infection (LTBI) have not been successful in complete eradication of the disease. Current screening modalities of TB include tuberculin skin testing (TST) and/or interferon-γ release assay (IGRA). However, these screening tests have been heavily studied in healthy populations but not in the elderly who are more likely to have multiple risk factors for progression to active TB from LTBI. The largest population that is harboring LTBI is the elderly, specifically those residing in nursing homes. Yet, unfortunately, guidelines for standards of detection and treatment for this specific group are lacking. In this review, we look at TST versus IGRA screening for LTBI in the elderly living in nursing homes. We review a cross-sectional study done at Staten Island University Hospital, and several other assessments of the sensitivity and accuracy of both screening tools. Furthermore, this review looks at the appropriateness of current LTBI treatment and prophylaxis in elderly patients residing in close quarters. The reviews point to the superiority of IGRA testing in the elderly for screening LTBI. The IGRA has been shown to be more sensitive to the detection of LTBI than TST. Additionally, medical complexities that the elderly population possesses may present challenges and resistance to standard treatments of LTBI. It is recommended via the literature that the addition of vitamin D, or alternative therapies (e.g. rifampin) could produce better outcomes for elderly patients with LTBI than the current 9 months of isoniazid (INH). As the older adults represent the fastest growing segment of our population and the largest LTBI reservoir in the USA, revisiting screening and treatment of LTBI in the elderly living in nursing homes may prove to lead to a path of TB eradication once and for all.