title: Performance of symptom-based tuberculosis screening among people living with HIV: not as great as hoped.
abstract: OBJECTIVE
  The objective of the present study was to determine the diagnostic performance of the symptom-based tuberculosis (TB) screening questionnaire recommended by WHO for people living with HIV (PLWH) in resource-limited settings, among adults off and on antiretroviral therapy (ART).
  
  
  METHODS
  Cross-sectional study at two HIV clinics in South Africa.
  
  
  METHODS
  A total of 825 PLWH completed the screening questionnaire and underwent investigations [chest radiography (CXR) and microbiologic testing of sputa]. A positive screen was defined as presence of cough, fever, night sweats, or weight loss. Pulmonary tuberculosis (PTB) was defined as sputum smear positive for acid-fast bacilli or growth of Mycobacterium tuberculosis.
  
  
  RESULTS
  Of 737 participants with at least one diagnostic sputum specimen, PTB was diagnosed in 31 of 522 (5.9%) on ART, and 34 of 215 (15.8%) not on ART. The questionnaire missed 15 of 31 (48.4%) PTB cases on ART, and three of 34 (8.8%) not on ART. Among participants on ART, post-test probability of PTB diagnosis (95% confidence interval) was 6.8% (4.0-10.9%) if screening positive, and 5.2% (2.9-8.4%) if screening negative, whereas among participants not on ART, post-test probabilities were 20.3% (14.2-27.5%) and 4.8% (1.0-13.5%), respectively. Among participants diagnosed with PTB, those on ART were significantly less likely to screen positive (adjusted odds ratio 0.04, 95% confidence interval: 0.01-0.39). In both groups (ART and no ART), screening was more sensitive when CXR was incorporated.
  
  
  CONCLUSIONS
  For case detection and exclusion of PTB, the WHO-recommended questionnaire performed adequately among PLWH not on ART, and poorly among those on ART. Further research is needed to identify feasible and effective TB screening strategies for PLWH in resource-limited settings.
authors.affiliation: aICAP Columbia University bDepartment of Epidemiology, Columbia University, Mailman School of Public Health, New York, New York, USA cICAP-Columbia, Pretoria dDepartment of Internal Medicine, Cecilia Makiwane Hospital, East London, South Africa.
authors.forename: Faiz
authors.initials: F
authors.lastname: Ahmad Khan
authors.forename: Sabine
authors.initials: S
authors.lastname: Verkuijl
authors.forename: Andrew
authors.initials: A
authors.lastname: Parrish
authors.forename: Fadzai
authors.initials: F
authors.lastname: Chikwava
authors.forename: Raphael
authors.initials: R
authors.lastname: Ntumy
authors.forename: Wafaa
authors.initials: W
authors.lastname: El-Sadr
authors.forename: Andrea A
authors.initials: AA
authors.lastname: Howard
mesh_terms: D000328:Adult; D019380:Anti-HIV Agents / Q000627:therapeutic use; D023241:Antiretroviral Therapy, Highly Active / Q000379:methods; D015510:Clinical Medicine / Q000379:methods*; D003430:Cross-Sectional Studies; D003906:Developing Countries; D005260:Female; D015658:HIV Infections / Q000150:complications* / Q000188:drug therapy; D006801:Humans; D008297:Male; D008403:Mass Screening / Q000379:methods*; D008853:Microscopy / Q000379:methods; D008875:Middle Aged; D013019:South Africa; D011795:Surveys and Questionnaires; D014376:Tuberculosis / Q000175:diagnosis* / Q000382:microbiology / Q000473:pathology*
chemical_list: D019380:Anti-HIV Agents