Performance of Clinical Screening Algorithms for Tuberculosis Intensified Case Finding among People Living with HIV in Western Kenya

PLoS One. 2016 Dec 9;11(12):e0167685. doi: 10.1371/journal.pone.0167685. eCollection 2016.

Abstract

Objective: To assess the performance of symptom-based screening for tuberculosis (TB), alone and with chest radiography among people living with HIV (PLHIV), including pregnant women, in Western Kenya.

Design: Prospective cohort study.

Methods: PLHIV from 15 randomly-selected HIV clinics were screened with three clinical algorithms [World Health Organization (WHO), Ministry of Health (MOH), and "Improving Diagnosis of TB in HIV-infected persons" (ID-TB/HIV) study], underwent chest radiography (unless pregnant), and provided two or more sputum specimens for smear microscopy, liquid culture, and Xpert MTB/RIF. Performance of clinical screening was compared to laboratory results, controlling for the complex design of the survey.

Results: Overall, 738 (85.6%) of 862 PLHIV enrolled were included in the analysis. Estimated TB prevalence was 11.2% (95% CI, 9.9-12.7). Sensitivity of the three screening algorithms was similar [WHO, 74.1% (95% CI, 64.1-82.2); MOH, 77.5% (95% CI, 68.6-84.5); and ID-TB/HIV, 72.5% (95% CI, 60.9-81.7)]. Sensitivity of the WHO algorithm was significantly lower among HIV-infected pregnant women [28.2% (95% CI, 14.9-46.7)] compared to non-pregnant women [78.3% (95% CI, 67.3-86.4)] and men [77.2% (95% CI, 68.3-84.2)]. Chest radiography increased WHO algorithm sensitivity and negative predictive value to 90.9% (95% CI, 86.4-93.9) and 96.1% (95% CI, 94.4-97.3), respectively, among asymptomatic men and non-pregnant women.

Conclusions: Clinical screening missed approximately 25% of laboratory-confirmed TB cases among all PLHIV and more than 70% among HIV-infected pregnant women. National HIV programs should evaluate the feasibility of laboratory-based screening for TB, such as a single Xpert MTB/RIF test for all PLHIV, especially pregnant women, at enrollment in HIV services.

MeSH terms

  • Adolescent
  • Adult
  • Female
  • HIV Infections / complications*
  • HIV Infections / epidemiology
  • Humans
  • Kenya / epidemiology
  • Male
  • Mass Chest X-Ray
  • Middle Aged
  • Pregnancy
  • Prospective Studies
  • Tuberculosis / complications*
  • Tuberculosis / diagnosis*
  • Tuberculosis / epidemiology
  • Young Adult

Grant support

Primary funding for this study was provided by the U.S. President’s Emergency Plan for AIDS Relief through Cooperative Agreement 5U19GH000041 from the Centers for Disease Control and Prevention to the Kenya Medical Research Institute. Additional funding was provided by the United States Agency for International Development. Approval for study design was obtained from the U.S. President's Emergency Plan for AIDS Relief Public Health Evaluation Scientific Committee. The funders had no role in data collection, analysis, decision to publish or preparation of the manuscript.