549. Cost-Effectiveness of WHO-Recommended Algorithms for TB Case Finding at Ethiopian HIV Clinics
Session: Poster Abstract Session: Tuberculosis Epidemiology and Diagnosis
Thursday, October 27, 2016
Room: Poster Hall
Posters
  • 161023 IDSA poster.pdf (250.0 kB)
  • Background: The World Health Organization (WHO) recommends active tuberculosis (TB) case finding and the use of a rapid molecular diagnostic test (Xpert MTB/RIF) to detect TB among people living with HIV (PLHIV) in high burden settings. Information on the cost-effectiveness of these recommended strategies is crucial for implementation in resource-limited settings.

    Methods: We conducted a model-based cost-effectiveness analysis comparing two algorithms for TB screening and diagnosis at HIV clinics in Ethiopia: (1) a WHO-recommended symptom screen combined with Xpert for PLHIV with positive symptom screen; and (2) current recommended practice algorithm (CRPA), which includes sequential (a) WHO-recommended symptom screen, (b) smear microscopy for those with a positive symptom screen, and (c) clinical diagnosis and empiric treatment for selected patients with negative smear microscopy. Our primary outcome was US$ per disability-adjusted life year (DALY) averted. Secondary outcomes were additional true positive diagnoses with symptom screen/Xpert, and false negative and false positive diagnoses averted.

    Results: Compared to CRPA, combining two WHO-recommendations—a WHO symptom screen with Xpert for those with a positive symptom screen—was highly cost effective for TB diagnosis among PLHIV (incremental cost of $21 per DALY averted). Among a cohort of 15,000 PLHIV with TB prevalence of 6%, this algorithm detected 54 more true positive cases than CRPA, and averted 2059 false positive and 54 false negative diagnoses. Per 15,000 patients, the WHO-recommended algorithm was modestly more costly ($252,000) than CRPA ($225,000). Cost-effectiveness of the symptom screen/Xpert algorithm was largely robust to sensitivity analyses.

    Conclusion: In this model-based analysis, combining a WHO-recommended symptom screen with Xpert for TB diagnosis among PLHIV was highly cost-effective ($21 per DALY averted) and more sensitive and specific than CRPA in a high-burden, resource-limited setting. The high number of false positive diagnoses in CRPA was due to low specificity of both the WHO-recommended symptom screen and clinical diagnosis. High cost of symptom screen and Xpert will require additional resources for widespread scale up and implementation.

    Max Adelman, M.D., M.Sc.1,2, Deborah Mcfarland, M.P.H., Ph.D.3, Mulugeta Tsegaye, M.D.4, Russell Kempker, M.D., M.Sc.5, Abraham Aseffa, M.D., Ph.D.6 and Henry Blumberg, M.D., FIDSA, FSHEA5,7, (1)Massachusetts General Hospital, Boston, MA, (2)Emory University School of Medicine, Atlanta, GA, (3)Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, GA, (4)Training Division, ALERT Hospital, Addis Ababa, Ethiopia, (5)Division of Infectious Disease, Department of Medicine, Emory University School of Medicine, Atlanta, GA, (6)Armauer Hansen Research Institute, Addis Ababa, Ethiopia, (7)Grady Memorial Hospital, Atlanta, GA

    Disclosures:

    M. Adelman, None

    D. Mcfarland, None

    M. Tsegaye, None

    R. Kempker, None

    A. Aseffa, None

    H. Blumberg, None

    Findings in the abstracts are embargoed until 12:01 a.m. CDT, Wednesday Oct. 26th with the exception of research findings presented at the IDWeek press conferences.