Does the Implementation of an Interferon-y Release Assay in Lieu of a Tuberculin Skin Test Increase Acceptance of Preventive Therapy for Latent Tuberculosis Among Healthcare Workers?
Note the all important phrase;
All HCWs undergo tuberculosis screening at the time of hire at the Cleveland Clinic;
Judging by the following extract it appears that HCWs had more confidence in QFT and switching to QFT was successful in achieving treatment for LTBI;
Achieving compliance among healthcare workers (HCWs) with treatment guidelines for latent tuberculosis infection (LTBI) has been challenging; compliance rates range from 8% to 60%, especially in foreign-born people with a history of bacille Calmette_Gue´rin (BCG) vaccination.1-4 The tuberculin skin test (TST) has been the traditional screening tool for LTBI. The Centers for Disease Control and Prevention has recently endorsed using whole blood interferon-g release assays (IGRAs), as an alternative to the TST, to screen for LTBI.5 We report the impact of the implementation of IGRAs on acceptance of preventive therapy for LTBI among newly hired HCWs in our institution.
All HCWs undergo tuberculosis screening at the time of hire at the Cleveland Clinic; this screening includes a questionnaire in the electronic health record about previous BCG testing and tuberculosis exposures. HCWs with a positive TST result (defined as an induration of at least 15 mm in diameter and/or a verified prior positive TST result) receive a chest x-ray to rule out active pulmonary disease and are offered treatment for LTBI. In July 2007, the QuantiFERON TB Gold In-Tube Assay (Cellestis), a whole-blood IGRA, was implemented in place of the TST to screen for LTBI among newly hired HCWs. HCWs with a positive IGRA result received a chest x-ray to rule out active pulmonary disease...
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..The acceptance rate for treatment among HCWs with LTBI and a positive IGRA test result was greater than 50% at our institution. This rate was significantly higher than the rate indicated by a survey of HCWs with LTBI in the 6-month period before implementation of IGRAs. The generalizability of the findings should be reviewed in the context that 75% of newly hired HCWs with LTBI at our institution were foreign born and had a history of BCG vaccination. A limitation of our study is that we have data on initiation of treatment but not on completion. However, Parsyan et al.7 noted in their study that the interventions aimed at completion of the prophylaxis should focus on the first month of therapy. Also, the low response rate (32%) for the survey administered to the HCWs with positive TST results before the implementation of IGRAs is a potential source of study bias. This study was not designed to explain the reasons for the difference in rates of acceptance of the treatment.
In summary, the majority of newly hired HCWs diagnosed with LTBI at our institution are foreign born and have a history of BCG vaccination. The implementation of an IGRA in lieu of a TST for screening may increase acceptance of preventive therapy for LTBI among HCWs.
