Increasing outpatient fluoroquinolone exposure before tuberculosis diagnosis and impact on culture-negative disease.
BACKGROUND
Fluoroquinolones are widely used to treat routine bacterial infections, but they are also potential first-line antituberculosis agents. Empirical fluoroquinolone therapy can delay the diagnosis of tuberculosis and cause resistance in Mycobacterium tuberculosis. Rates of fluoroquinolone exposure before tuberculosis diagnosis and the impact of fluoroquinolones on culture-negative tuberculosis have not been previously reported.


METHODS
All newly diagnosed tuberculosis cases reported to the Tennessee Department of Health between January 1, 2000, and December 31, 2004, were cross-matched with the TennCare (Medicaid) pharmacy database to assess for outpatient fluoroquinolone use in the 12 months before tuberculosis diagnosis.


RESULTS
Of 1,562 tuberculosis cases reported, 1,055 occurred in TennCare participants; of these 1,055 TennCare patients, 507 were enrolled in TennCare more than 300 days during the year before tuberculosis diagnosis. Of the 507 patients, 119 (23%) received a fluoroquinolone before tuberculosis diagnosis. The proportion of fluoroquinolone-exposed patients increased from 9% in 2000 to 41% in 2004 (chi(2) test for trend P <.001). In multivariate logistic regression analysis, factors associated with fluoroquinolone exposure were older age (odds ratio [OR], 1.03 per year; 95% confidence interval [CI], 1.02-1.04) and year of diagnosis (OR, 1.64 per 1-year increase; 95% CI, 1.39-1.93); human immunodeficiency virus infection tended to be associated with increased exposure (OR, 1.94; 95% CI, 0.97-3.90). After controlling for age, sex, race, site of disease, human immunodeficiency virus, and year of diagnosis, prior fluoroquinolone exposure was not associated with culture-negative tuberculosis (OR, 0.81; 95% CI, 0.41-1.60).


CONCLUSIONS
Fluoroquinolone use before tuberculosis diagnosis increased significantly during the study period. However, fluoroquinolone exposure was not associated with an increased risk of culture-negative tuberculosis.
Department of Medicine, Division of Infectious Diseases, Vanderbilt University, 1161 21st Ave, A2209 MCN, Nashville, TN 37232-2582, USA.
Pinky D
PD
Gaba
Connie
C
Haley
Marie R
MR
Griffin
Ed
E
Mitchel
Jon
J
Warkentin
Erin
E
Holt
Pam
P
Baggett
Timothy R
TR
Sterling
D000328:Adult; D000368:Aged; D002939:Ciprofloxacin / Q000627:therapeutic use; D005260:Female; D024841:Fluoroquinolones / Q000627:therapeutic use*; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009169:Mycobacterium tuberculosis / Q000187:drug effects* / Q000302:isolation & purification; D015242:Ofloxacin / Q000627:therapeutic use; D010045:Outpatients / Q000706:statistics & numerical data; D010604:Pharmacy / Q000706:statistics & numerical data; D012307:Risk Factors; D013714:Tennessee; D013997:Time Factors; D014376:Tuberculosis / Q000175:diagnosis* / Q000382:microbiology
D024841:Fluoroquinolones; D002939:Ciprofloxacin; D015242:Ofloxacin