High Prevalence Of Subclinical Tuberculosis In HIV-1 Infected Persons Without Advanced Immunodeficiency: Implications For TB Screening Tolu ONI Imperial College London University of Cape Town 20 June 2011 Abstract no. WEPDB0206

INTRODUCTION AIM  To describe the prevalence and outcome of subclinical TB disease in HIV-1-infected persons not eligible for ART. METHODS  Setting: Khayelitsha  Participants: asymptomatic persons from pre-ART wellness clinic or at HCT (+162 symptomatic TB cases for comparison)  TB screening, Tuberculin skin test (TST), CXR if TST >4mm  Spoligotyping

KEY FINDINGS  8.5% (95% C.I %) prevalence of asymptomatic TB disease, with good clinical outcomes  Spoligotyping effectively excludes cross-contamination  71% of those with TST ≥ 5mm had normal CXR  Findings suggest lower bacterial burden compared to symptomatic TB cases  56% progressed clinically, median 28 days later  Suggests increasing bacterial load and actively replicating bacilli  Treatment received earlier with potential public health significance (22% smear positive)

POLICY IMPLICATIONS  Results suggest that in high HIV/TB transmission settings, HIV-1 infection should prompt a TB test by sputum culture especially in persons with -TST ≥5mm (OR 4.96; p=0.064) - lower CD4 counts (OR 0.996; p=0.06) - longer history of HIV (OR 1.006; p=0.056)  Highlights need for new rapid and affordable point-of-care diagnostic tests to identify persons with clinical and subclinical TB disease.

ACKNOWLEDGMENTS  Lebo Tsekela  Hannah Gideon  Nonzwakazi Bangani  Ronnett Seldon  Rachael Burke  Kathryn Wood  Katalin Wilkinson  Tom Ottenhoff  Robert Wilkinson  Study Participants