What is the recommended treatment for a urinary tract infection (UTI) in pregnancy within an emergency room (ER) setting?

Treatment of UTIs in Pregnancy in the Emergency Room Setting

For pregnant women with UTI in the emergency room setting, first-line treatment should be nitrofurantoin 100 mg twice daily for 5 days, unless contraindicated. 1

Diagnostic Approach

• Obtain urine culture before initiating antibiotics to confirm diagnosis and guide therapy
• Symptoms typically include dysuria, frequency, urgency, and possibly hematuria
• Pregnancy is considered a complicating factor for UTI, requiring careful management

First-Line Treatment Options

Nitrofurantoin

• Dosage: 100 mg twice daily for 5 days 1
• Advantages: Low resistance rates, effective concentration in urinary tract
• Contraindications: Near term (36+ weeks), G6PD deficiency, renal insufficiency

Fosfomycin

• Dosage: 3 g single dose
• Advantages: Single-dose therapy, good safety profile in pregnancy
• Note: Comparable efficacy to nitrofurantoin for uncomplicated UTI 2

Amoxicillin/Clavulanate

• Dosage: 500 mg three times daily for 3-5 days
• Use: When first-line agents are contraindicated or based on culture results

Treatment Algorithm

1. Uncomplicated cystitis in pregnancy:

   • Nitrofurantoin 100 mg twice daily for 5 days (first choice)
   • Fosfomycin 3 g single dose (alternative)
   • Cephalexin 500 mg four times daily for 5-7 days (alternative)

2. Suspected pyelonephritis or signs of systemic infection:

   • Hospitalization for IV antibiotics
   • Ceftriaxone or ampicillin plus gentamicin
   • Switch to oral therapy based on culture results once clinically improved

3. Post-treatment follow-up:

   • Repeat urine culture 1-2 weeks after completing treatment to confirm cure 1
   • Monthly urine cultures throughout pregnancy due to high recurrence risk

Special Considerations

Antimicrobial Stewardship

• Choose antibiotics based on local resistance patterns
• Avoid fluoroquinolones and trimethoprim in first trimester
• Avoid tetracyclines throughout pregnancy

Prevention of Recurrence

• For women with history of recurrent UTIs, consider prophylaxis
• Post-coital prophylaxis with cephalexin 250 mg or nitrofurantoin 50 mg has shown significant reduction in UTI recurrence during pregnancy 3

Potential Complications

• Untreated or inadequately treated UTIs in pregnancy can lead to:
  • Pyelonephritis (increased risk during pregnancy)
  • Preterm birth
  • Low birth weight
  • Maternal sepsis

Pitfalls to Avoid

1. Treating asymptomatic bacteriuria without confirmation: Always confirm diagnosis with urine culture
2. Delaying treatment: Prompt treatment is essential to prevent ascending infection
3. Inadequate follow-up: Ensure post-treatment cultures are obtained
4. Using contraindicated antibiotics: Avoid tetracyclines, fluoroquinolones in pregnancy
5. Missing pyelonephritis: Assess for systemic symptoms (fever, flank pain, nausea/vomiting)

UTIs in pregnancy require prompt attention and appropriate antibiotic therapy to prevent complications affecting both mother and fetus. The emergency room physician should initiate appropriate treatment while ensuring proper follow-up with obstetric care.