AANP Family Nurse Practitioner (FNP) Certification ExamEvaluationMedium
A 28-year-old female presents with a 3-day history of dysuria, frequency, and urgency. Urinalysis reveals positive leukocyte esterase, nitrites, and >100,000 CFU/mL E. coli. She has no fever or flank pain. She reports a penicillin allergy (rash). What is the most appropriate initial antibiotic for this uncomplicated urinary tract infection (UTI)?
- ANitrofurantoin
- BCiprofloxacin
- CAmoxicillin-clavulanate
- DTrimethoprim-sulfamethoxazole (TMP-SMX)
Show answer & explanationAnswer & explanation
Correct answer: A. Nitrofurantoin
Nitrofurantoin is a first-line agent for uncomplicated UTIs due to its excellent efficacy against common uropathogens like E. coli and its low resistance rates. It is also safe in penicillin-allergic patients.
Why the other options are wrong
- B. Ciprofloxacin, a fluoroquinolone, is effective but generally reserved for more complicated UTIs or when other first-line agents cannot be used due to increasing resistance and potential for severe side effects.
- C. Amoxicillin-clavulanate is a penicillin derivative and should be avoided in patients with a penicillin allergy.
- D. TMP-SMX is a first-line agent but should be avoided if local resistance rates are high (>20%) or if there's a sulfa allergy. Nitrofurantoin is a better choice if TMP-SMX resistance is a concern.
Uncomplicated UTI Management
Uncomplicated UTIs in healthy non-pregnant women are typically treated with short courses of antibiotics, with nitrofurantoin, TMP-SMX, or fosfomycin as first-line options.
- E. coli is the most common pathogen.
- Choose antibiotics based on local resistance patterns and patient allergies.
- Fluoroquinolones are generally reserved for more severe infections.
Memory trick: For a simple UTI, choose the bladder-focused meds, but mind the allergies and resistance.