Carol, a 48-year-old woman, presents with a community-acquired UTI. She has a pa
ID: 3506531 • Letter: C
Question
Carol, a 48-year-old woman, presents with a community-acquired UTI. She has a past medical history significant only for several previous episodes of UTI. A urinalysis is ordered with the following results:
Appearance, straw-colored and turbid (normal, strawcolored and clear)
Specific gravity, 1.028 pH, 6.3
Glucose, ketones, and bilirubin, all negative (normal, all negative)
Blood and protein, both trace positive by dipstick (normal, both negative)
WBC, 10 to 15 cells/LPF (normal, 0–2 cells/LPF)
RBC, 5 to 10 cells/LPF (normal, 0–2 cells/ LPF)
Bacteria, many (normal, 0 to rare)
Epithelial cells, 3 to 5 cells/LPF (normal, 0 to few cells/LPF)
Leukocyte esterase and nitrite tests by dipstick, both positive (normal, both negative)
Of note, Carol has experienced a rash with TMP-SMX and has a type I hypersensitivity reaction to penicillins in the past.
Q1: What is community-acquired UTI?
Q2: What is the role of fluoroquinolones in the treatment of Carol’s community-acquired UTI?
Q3: What are some examples of fluoroquinolones?
Q4: The activity of many fluoroquinolones in vitro is antagonized by urine (acidic pH, divalent cations). Please explain it. What’s your suggestions for your patients?
Q5: Please describe the fluoroquinolone resistance in UTI?
Explanation / Answer
1. Community acquired UTI is nothing but the most common infection caused by extended spectrum beta lactamase which produces Enterobacteriaceae.
2. Fluoroquinones are recommended when resistance is high. It is used in empirical treatment of uncomplicated and complicated UTI's which is caused by trimethoprim sulfamethaxazole resistant uropathogens.
Fluoroquinones exhibit concentration dependent antibacterial activity, high renal excretion, relatively early and prolonged urinary bactericidal concentration.
3. Examples include ciprofloxacin, levofloxacin, gemifloxacin, moxifloxacin, norfloxacin, ofloxacin.
4. Physicians should consider the urinary pH of patients when treating UTI especially in case of major complications. Further clinical investigations should examine urinary pH and antibiotic efficacy which may result in application of decreased antibiotic dosages and regimen duration by reducing antibiotic resistance development.
5. Fluoroquinone resistance in UTI exhibits a multiple antibiotic resistance phenotype as well as high level resistance. Resistance to fluoroquinones is a result of combination of mechanisms which act either in single way or in combination to produce resistant phenotype.