Utility of QuantiFERON tuberculosis gold-in-tube test for detecting latent tuberculosis infection among close household contacts of confirmed tuberculosis patients in Accra, Ghana.
Introduction of the interferon gamma (IFN-γ) release assays with their higher sensitivity and specificity over the traditional tuberculin skin test has improved testing for latent tuberculosis infection (LTBI). None of the IFN-γ release assays has ever been used to screen for LTBI in Ghana. This study set out to determine the utility of the QuantiFERON TB Gold-in-Tube (QFT-GIT) test for the diagnosis of LTBI among close household contacts of newly diagnosed sputum smear-positive tuberculosis (TB) patents in Accra, Ghana, and the associated risk factors for a positive QFT-GIT test.



Close household contacts of newly diagnosed sputum smear-positive patients receiving anti-TB therapy from three hospitals in Accra were recruited, after providing written informed consent, between April 2012 and December 2014. In addition to demographic details, 2 mL of blood was collected from all participants for the QFT-GIT test for LTBI diagnosis.



Out of 112 eligible consenting participants, the QFT-GIT test was performed for 100 participants. The prevalence of LTBI (QFT-GIT positive) was 65%, with 32% being QFT-GIT negative and 3% indeterminate results. Contacts aged >15 years were more likely to be QFT-GIT positive than those aged >15 years, regardless of their Bacillus Calmette-Guerin status. There was significantly higher QFT-GIT test positivity in adult contacts who were parents, siblings, or spouses to index cases than in child contacts (P = 0.0016, P = 0.04, and P = 0.0003, respectively).



The QFT-GIT test will be a useful tool for screening of TB contacts for LTBI in Ghana.
Department of Bacteriology, Noguchi Memorial Institute for Medical Research, University of Ghana, Ghana, UK.
Gloria Ivy
GI
Mensah
Department of Biochemistry, Cell and Molecular Biology, University of Ghana, Accra, Ghana, UK.
Sandra Akoley
SA
Sowah
Department of Biochemistry, Cell and Molecular Biology, University of Ghana, Accra, Ghana, UK.
Nana Yaw Asare
NY
Yeboah
Department of Bacteriology, Noguchi Memorial Institute for Medical Research, University of Ghana, Ghana, UK.
Kennedy Kwasi
KK
Addo
Department of Infectious Diseases and Tropical Medicine, London School of Hygiene and Tropical Medicine, London, UK.
Dolly
D
Jackson-Sillah
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D002675:Child, Preschool; D016358:Contact Tracing; D005191:Family Characteristics; D005260:Female; D005869:Ghana / Q000453:epidemiology; D006801:Humans; D059425:Interferon-gamma Release Tests / Q000379:methods*; D055985:Latent Tuberculosis / Q000175:diagnosis* / Q000453:epidemiology / Q000382:microbiology; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D013183:Sputum / Q000382:microbiology; D014374:Tuberculin Test / Q000379:methods*; D014376:Tuberculosis / Q000453:epidemiology / Q000382:microbiology; D055815:Young Adult