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. 2017 Apr 8;16(1):25.
doi: 10.1186/s12941-017-0202-4.

High fluoroquinolone MIC is associated with fluoroquinolone treatment failure in urinary tract infections caused by fluoroquinolone susceptible Escherichia coli

Pinyo Rattanaumpawan  1   2 , Irving Nachamkin  3 , Warren B Bilker  4 , Jason A Roy  4 , Joshua P Metlay  5 , Theoklis E Zaoutis  6 , Ebbing Lautenbach  6   7 ; CDC prevention epicenters program
Affiliations

High fluoroquinolone MIC is associated with fluoroquinolone treatment failure in urinary tract infections caused by fluoroquinolone susceptible Escherichia coli

Pinyo Rattanaumpawan et al. Ann Clin Microbiol Antimicrob. .

Abstract

Background: Suboptimal clinical response to fluoroquinolone (FQ) therapy has been clearly documented in patients with Salmonella typhi infection with reduced FQ susceptibility. However, the clinical impact of reduced FQ susceptibility on other infections including E. coli urinary tract infections (UTIs) has never been evaluated.

Methods: We conducted a retrospective cohort study of female patients with fluoroquinolone susceptible E. coli (FQSEC) UTIs who received FQ therapy at outpatient services within University of Pennsylvania Health System, Philadelphia. Exposed patients were those with high MIC-FQSEC UTIs (the levofloxacin MIC > 0.12 but ≤ 2 mg/L) while unexposed patients were those with low MIC-FQSEC UTIs (the levofloxacin MIC ≤ 0.12 mg/L). The primary treatment outcome was treatment failure within 10 weeks after initiation of FQ therapy.

Results: From May 2008 to April 2011, we enrolled 29 exposed patients and 246 unexposed patients. Two patients in each group experienced treatment failure; exposed vs. unexposed (6.9 vs. 0.8%; p = 0.06). Risk difference and risk ratio (RR) for treatment failure were 0.06 [95% CI -0.03-0.15; exact-p = 0.06] and 8.48 [95% CI 1.24-57.97; exact-p = 0.06], respectively. After adjusting for underlying cerebrovascular disease, the RR was 7.12 (95% CI 1.20-42.10; MH-p = 0.04).

Conclusion: Our study demonstrated the negative impact of reduced FQ susceptibility on the treatment response to FQ therapy in FQSEC UTIs. This negative impact may be more intensified in other serious infections. Future studies in other clinical situations should be conducted to fill the gap of knowledge.

Keywords: Escherichia coli; Fluoroquinolone resistance; Urinary tract infection.

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References

    1. Clinical and Laboratory Standards Institute . Performance standards for antimicrobial susceptibility testing: twentieth informational supplement M100-S20. Wayne: CLSI; 2010.
    1. McDonald LC, Chen FJ, Lo HJ, Yin HC, Lu PL, Huang CH, et al. Emergence of reduced susceptibility and resistance to fluoroquinolones in Escherichia coli in Taiwan and contributions of distinct selective pressures. Antimicrob Agents Chemother. 2001;45:3084–3091. doi: 10.1128/AAC.45.11.3084-3091.2001. - DOI - PMC - PubMed
    1. Lautenbach E, Metlay JP, Mao X, Han X, Fishman NO, Bilker WB, et al. The prevalence of fluoroquinolone resistance mechanisms in colonizing Escherichia coli isolates recovered from hospitalized patients. Clin Infect Dis. 2010;51:280–285. doi: 10.1086/653931. - DOI - PMC - PubMed
    1. Gales AC, Gordon KA, Wilke WW, Pfaller MA, Jones RN. Occurrence of single-point gyrA mutations among ciprofloxacin-susceptible Escherichia coli isolates causing urinary tract infections in Latin America. Diagn Microbiol Infect Dis. 2000;36:61–64. doi: 10.1016/S0732-8893(99)00121-2. - DOI - PubMed
    1. Slinger R, Desjardins M, McCarthy AE, Ramotar K, Jessamine P, Guibord C, et al. Suboptimal clinical response to ciprofloxacin in patients with enteric fever due to Salmonella spp. with reduced fluoroquinolone susceptibility: a case series. BMC Infect Dis. 2004;4:4p. doi: 10.1186/1471-2334-4-36. - DOI - PMC - PubMed

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