title: Using tuberculin skin test as an entry point to screen for latent and active tuberculosis in Thai people living with HIV.
abstract: BACKGROUND
  Tuberculin skin test (TST) identifies patients highly likely to benefit from isoniazid preventive therapy and tuberculosis (TB) prevalence may differ by TST status. We evaluated latent and active TB screening and diagnosis strategies among people living with HIV (PLHIV) incorporating TST as the initial screening step.
  
  
  METHODS
  PLHIV attending services at the Thai Red Cross Anonymous Clinic during September 2006 to January 2008 were enrolled. TB disease was defined as any positive Mycobacterium tuberculosis (MTB) specimen culture from sputum, urine, stool, lymph node aspiration, and blood. The performance of symptom screening (>1 of: any cough, any fever, night sweats lasting 3 or more weeks in the preceding 4 weeks) and laboratory screening (sputum smear followed by chest radiography and CD4 count) for active TB disease were evaluated according to TST status.
  
  
  RESULTS
  We enrolled 604 PLHIV. TST was positive in 151 PLHIV (25.0%). TB disease was diagnosed in 33 PLHIV, including 22 (14.6%) TST-positive and 11 (2.4%) TST-negative PLHIV. We found that an approach of performing MTB culture for all TST-positive PLHIV and symptom screening followed by laboratory screening for all TST-negative PLHIV would identify 196 (32.4%) of 604 PLHIV who would need MTB culture to correctly diagnose 29 (87.9%) of 33 active TB cases.
  
  
  CONCLUSIONS
  TST can be used as an initial screening test among PLHIV to identify those at highest risk of active TB disease. Access to MTB culture or other sensitive tests to exclude TB disease is urgently needed to improve TB screening and prevention in resource-limited settings.
authors.affiliation: Thai Red Cross AIDS Research Centre, Bangkok, Thailand. nittaya.p@trcarc.org
authors.forename: Nittaya
authors.initials: N
authors.lastname: Phanuphak
authors.forename: Jay K
authors.initials: JK
authors.lastname: Varma
authors.forename: Wanitchaya
authors.initials: W
authors.lastname: Kittikraisak
authors.forename: Nipat
authors.initials: N
authors.lastname: Teeratakulpisarn
authors.forename: Saranya
authors.initials: S
authors.lastname: Phasitlimakul
authors.forename: Pailin
authors.initials: P
authors.lastname: Suwanmala
authors.forename: Tippawan
authors.initials: T
authors.lastname: Pankam
authors.forename: Thanyathorn
authors.initials: T
authors.lastname: Burapat
authors.forename: Theerawit
authors.initials: T
authors.lastname: Tasaneeyapan
authors.forename: Kimberly D
authors.initials: KD
authors.lastname: McCarthy
authors.forename: Kevin P
authors.initials: KP
authors.lastname: Cain
authors.forename: Praphan
authors.initials: P
authors.lastname: Phanuphak
mesh_terms: D000328:Adult; D005260:Female; D015658:HIV Infections / Q000150:complications*; D006801:Humans; D008297:Male; D008403:Mass Screening / Q000379:methods*; D009169:Mycobacterium tuberculosis / Q000276:immunology* / Q000302:isolation & purification; D013785:Thailand; D014374:Tuberculin Test / Q000379:methods*; D014376:Tuberculosis / Q000175:diagnosis*