Fluoroquinolone use before tuberculosis medical diagnosis delays the time to diagnosis and treatment and increases the risk of fluoroquinolone-resistant tuberculosis and death. during the six months before tuberculosis diagnosis. Fluoroquinolone exposure determined by review of inpatient and outpatient medical records was considered the gold standard for comparison. The FQ-Form had 61% (95% Confidence Interval [CI] 48-73%) sensitivity and 93% (95% CI 85-98%) specificity (agreement 79% kappa 0.56) while the in-home interview had 28% (95% CI 18-40%) sensitivity and 99% (94-100%) specificity (agreement 68% kappa 0.29). A simple questionnaire administered by health department personnel identified fluoroquinolone exposure before tuberculosis diagnosis with moderate reliability. Fluoroquinolones are the most frequently prescribed class of antibiotics in the United States . They are commonly used to treat a variety PFI-1 of bacterial infections and are often used empirically including for respiratory infections. As a result patients with tuberculosis may inadvertently receive treatment with a fluoroquinolone prior to tuberculosis diagnosis. Up to 41% of tuberculosis patients have received a fluoroquinolone prior to diagnosis . Patients who are treated with a fluoroquinolone before being diagnosed with tuberculosis have a higher risk of fluoroquinolone-resistant disease . When tested up to 3.6% of isolates are resistant to fluoroquinolones. In a study of culture-confirmed tuberculosis patients in Tennessee we previously found that seven out of 54 (13%) patients with > 10 days of fluoroquinolone exposure had fluoroquinolone-resistant tuberculosis. Fluoroquinolone exposure before tuberculosis diagnosis has also been associated with delays in the diagnosis and initiation of appropriate treatment for tuberculosis  and an increased risk of death at the time of tuberculosis diagnosis or during tuberculosis treatment . Since fluoroquinolones may be used in patients who do not tolerate first-line anti-tuberculosis medications and are under investigation for inclusion in first-line drug-susceptible tuberculosis PFI-1 treatment regimens preserving fluoroquinolone susceptibility and optimizing conditions for successful treatment are essential [7 8 The development of a rapid accurate method to assess the duration and timing of fluoroquinolone exposure prior to tuberculosis diagnosis could identify Rabbit Polyclonal to UBTD2. high-risk patients and have important implications for tuberculosis treatment. Specifically if a PFI-1 drug-susceptible tuberculosis patient identified as having extensive fluoroquinolone exposure prior to tuberculosis diagnosis were to develop intolerance to first-line anti-tuberculosis medications the provider might prioritize second-line drug susceptibility testing to better inform an alternate regimen. Published studies reporting patient fluoroquinolone exposure data have PFI-1 used various methods PFI-1 such as medical record review  and pharmacy databases linked to tuberculosis registries [2 3 10 The validity of PFI-1 such sources of exposure data has not been determined. In the current study we compared four methods of ascertaining fluoroquinolone exposure prior to diagnosis among tuberculosis patients in Tennessee. Fluoroquinolone exposure data were gathered for a prospective study that evaluated the relationship between antecedent fluoroquinolone exposure and fluoroquinolone resistance in culture-confirmed tuberculosis patients reported to the Tennessee Department of Health from January 2007 to December 2009 . For the current study we sought to understand the potential clinical value of fluoroquinolone exposure assessment methods. In a clinical context these methods would be implemented prior to identification of fluoroquinolone-resistant values were two-sided; values <0.05 were considered statistically significant. A total of 493 culture-confirmed tuberculosis patients were reported to the Tennessee Department of Health during the study period. Of these 177 (36%) consented to the in-home interview and signed a release of medical information form for medical record review. There were 128 (26%) patients who declined to participate 23 (5%) who could not be reached and 165 (33%) who did not meet eligibility criteria. The in-home interviews occurred a median of 70 days (IQR 49 107 after tuberculosis diagnosis. There were no statistically significant differences among patients who were enrolled and those not enrolled with regard.