Tuberculosis case finding: Supplement intensified case finding among acute lower respiratory infection (ALRI) hospitalized patients in Sa Kaeo province, Thailand.
Naowarat S., Rojanaworarit C., Surinsak W., Umain K., Ruadreaw D., Yuenprakone S., Pisutaporn A., Meeyai AC.
BACKGROUND AND PURPOSE: We aimed to estimate TB prevalence among in-patients hospitalized with acute lower respiratory infection (ALRI) through a routine TB case finding approach (Patient-Initiated-Pathway, PIP) and among those without initial TB detection by PIP using a supplementary-Intensified-Case-Finding (supplementary-ICF) approach to determine the extent of active TB infection in patients enrolled in population-based surveillance in Sa Keao, Thailand. We also investigated secondary TB transmission through household contacts (HHCs). METHODS: This was a prospective cross-sectional study. Data for hospitalized patients with ALRI were obtained from population-based pneumonia surveillance. PIP was provided in ALRI patients with suspected TB infection; those without initial suspicion of TB infection were evaluated for TB by the supplementary-ICF approach. For each active TB case finding approach, index cases were identified by acid-fast-bacillus testing and the TB prevalence was estimated. HHCs of each TB index case were followed to identify the extent of secondary TB infection. RESULTS: TB prevalence among ALRI hospitalized patients was 12.2% among those undergoing PIP and 6.8% among those undergoing supplementary-ICF. The total number of active TB cases was doubled after implementing the supplementary-ICF method. Secondary TB infection among HHCs was 3.5 times more common for contacts of index cases identified by routine active TB case finding compared to supplementary-ICF TB. CONCLUSION: Supplementary-ICF among ALRI hospitalizations would be expected to result in improved active TB case detection compared to the current policy of PIP. The supplementary-ICF also enhanced early case detection and showed lower prevalence of secondary infection.