Urgent Care For UTI 4 — Questions and Answers
Question 1: A patient presents with UTI symptoms and reports a sulfa allergy with anaphylaxis. Which antibiotic should be avoided?
- Nitrofurantoin
- Trimethoprim-sulfamethoxazole (Correct answer)
- Amoxicillin-clavulanate
- Ciprofloxacin
Correct answer: Trimethoprim-sulfamethoxazole
TMP-SMX contains sulfamethoxazole, a sulfonamide antibiotic that is contraindicated in patients with sulfa allergy, especially with anaphylaxis history.
Question 2: A 34-year-old woman at 32 weeks gestation develops fever, rigors, and flank pain. Blood cultures are drawn and IV antibiotics are started. Which antibiotic is CONTRAINDICATED due to potential fetal harm?
- Ceftriaxone
- Ampicillin-sulbactam
- Nitrofurantoin (near term) (Correct answer)
- Aztreonam
Correct answer: Nitrofurantoin (near term)
Nitrofurantoin is contraindicated at 36+ weeks gestation due to risk of neonatal hemolytic anemia from immature glutathione pathways.
Question 3: A 55-year-old woman with type 2 diabetes presents with a UTI. She takes metformin. Which antibiotic interaction requires caution if a fluoroquinolone is prescribed?
- Fluoroquinolones block metformin renal secretion, raising metformin levels
- Fluoroquinolones can cause hypoglycemia independently of metformin (Correct answer)
- Fluoroquinolones reduce renal clearance of insulin
- Fluoroquinolones are safe with no interaction with diabetes medications
Correct answer: Fluoroquinolones can cause hypoglycemia independently of metformin
Fluoroquinolones can independently disturb glucose homeostasis, causing both hypoglycemia and hyperglycemia, requiring blood sugar monitoring in diabetic patients.
Question 4: A urine culture grows E. coli with the following susceptibilities: resistant to TMP-SMX and ampicillin, susceptible to nitrofurantoin, ciprofloxacin, and ceftriaxone. The patient has uncomplicated cystitis and no allergies. What is the preferred oral treatment?
- Amoxicillin 500 mg three times daily for 7 days
- Nitrofurantoin 100 mg twice daily for 5 days (Correct answer)
- Ciprofloxacin 500 mg twice daily for 3 days
- Ceftriaxone 1 g IV once daily for 3 days
Correct answer: Nitrofurantoin 100 mg twice daily for 5 days
Nitrofurantoin is the preferred oral agent for uncomplicated cystitis when susceptible; fluoroquinolones should be reserved to preserve their use for serious infections.
Question 5: Which clinical finding would prompt you to classify a UTI as 'complicated' rather than uncomplicated?
- Female sex
- Age over 18
- Presence of a ureteral stent (Correct answer)
- Symptoms lasting more than 48 hours
Correct answer: Presence of a ureteral stent
Structural or functional urinary tract abnormalities such as a ureteral stent, indwelling catheter, or obstruction classify a UTI as complicated.
Question 6: A 68-year-old male nursing home resident is found to have 100,000 CFU/mL of E. coli on a routine urine culture. He has no dysuria, frequency, fever, or change in mental status. What is the recommended action?
- Treat with 3-day ciprofloxacin course
- Treat with 7-day TMP-SMX course
- No antibiotics; asymptomatic bacteriuria in elderly men does not require treatment (Correct answer)
- Refer to urology for evaluation
Correct answer: No antibiotics; asymptomatic bacteriuria in elderly men does not require treatment
IDSA guidelines recommend against treating asymptomatic bacteriuria in elderly patients as it does not reduce morbidity and increases antibiotic resistance.
Question 7: A patient with recurrent UTIs asks about post-coital antibiotic prophylaxis. Which statement is correct?
- A single dose of antibiotic taken within 2 hours after intercourse is an effective strategy (Correct answer)
- Post-coital prophylaxis requires a 3-day course each time
- This strategy is only approved for men
- Post-coital prophylaxis has no evidence and should not be offered
Correct answer: A single dose of antibiotic taken within 2 hours after intercourse is an effective strategy
A single prophylactic antibiotic dose taken within 2 hours of intercourse is evidence-based and reduces UTI risk in women whose infections are temporally linked to sexual activity.
Urgent Care For UTI 4
A patient presents with UTI symptoms and reports a sulfa allergy with anaphylaxis.
Which antibiotic should be avoided?