Failure of Ciprofloxacin Therapy in the Treatment of Community-Acquired Acute Pyelonephritis caused by In-Vitro Susceptible Escherichia coli Strain Producing CTX-Type Extended-Spectrum β-Lactamase

• Published in: Infection & chemotherapy Vol. 50; no. 4; pp. 357 - 361
• Main Authors: Seok, Hyeri, Cha, Min Kyeong, Kang, Cheol-In, Cho, Sun Young, Kim, So Hyun, Ha, Young Eun, Chung, Doo Ryeon, Peck, Kyong Ran, Song, Jae-Hoon
• Format: Journal Article
• Language: English
• Published: Korea (South) The Korean Society of Infectious Diseases and Korean Society for Chemotherapy 01.12.2018; 대한감염학회
• Subjects: Case Report; 내과학; CTX-M; Extended-spectrum beta-lactamase; Ciprofloxacin; Escherichia coli; Pyelonephritis
• ISSN: 2093-2340; 1598-8112; 2092-6448; 2092-6448
• DOI: 10.3947/ic.2018.50.4.357

While carbapenems are the drug of choice to treat extended-spectrum-β-lactamase (ESBL)-producing strains, some alternative carbapenem-sparing regimens are suggested for antibiotic stewardship. We experienced a case of ciprofloxacin treatment failure for acute pyelonephritis caused by an apparently susceptible . A 71-year-old woman presented the emergency department with fever for 7 days and bilateral flank pain for 2 days. The laboratory results and abdominopelvic computed tomography finding were compatible with acute pyelonephritis. During 3-day ciprofloxacin therapy, the patient remained febrile with persistent bacteremia. After the change in antibiotics to ertapenem, the patient's clinical course started to improve. ESBL-producing isolates were identified in all three consecutive blood samples. Pulsed-field gel electrophoresis (PFGE) patterns, serotypes, and sequence types showed the three isolates were derived from the identical strain. The isolates produced CTX-M-14 type ESBL belonging to the ST69 clonal group. Despite susceptibility, the failure was attributed to a point mutation encoding Ser83Leu within quinolone resistance-determining regions. This case suggests that ciprofloxacin should be used cautiously in the treatment of serious infections caused by ciprofloxacin-susceptible, ESBL-producing , even in acute pyelonephritis because susceptibility tests could fail to detect certain genetic mutations.