In an adult with an uncomplicated lower urinary tract infection and microscopic or mild gross hematuria, what first‑line oral antibiotic regimen and discharge plan (including urine culture, counseling, and follow‑up) should be used?

First-Line Antibiotic and Discharge Plan for Uncomplicated Lower UTI with Hematuria

For an adult with uncomplicated lower urinary tract infection and microscopic or mild gross hematuria, prescribe nitrofurantoin 100 mg orally twice daily for 5–7 days (women) or 7 days (men), obtain a urine culture before starting antibiotics, and arrange follow-up only if symptoms persist beyond 48–72 hours or recur within 2 weeks. 1, 2

First-Line Antibiotic Selection

• Nitrofurantoin 100 mg orally twice daily for 5–7 days is the preferred first-line agent because local resistance remains exceptionally low (<5%), urinary concentrations are high, and collateral damage to gut flora is minimal compared with fluoroquinolones or trimethoprim-sulfamethoxazole. 1, 3

• Fosfomycin trometamol 3 g as a single oral dose is an excellent alternative when adherence to a multi-day regimen is a concern or when nitrofurantoin is contraindicated. 1, 3

• Trimethoprim-sulfamethoxazole 160/800 mg (double-strength) twice daily for 3 days may be used only when local E. coli resistance is documented to be <20% and the patient has had no recent exposure to this antibiotic within the past 3 months. 1, 4, 3

• Avoid fluoroquinolones (ciprofloxacin, levofloxacin) as first-line therapy because they cause substantial disruption of the intestinal microbiome, promote resistance, and carry serious adverse effects (tendon rupture, peripheral neuropathy, QT-prolongation); reserve them for second-line use when first-line agents are unsuitable. 1, 3

Treatment Duration by Sex

• Women with uncomplicated cystitis: 5–7 days for nitrofurantoin, 3 days for trimethoprim-sulfamethoxazole (if susceptible), or a single dose of fosfomycin. 1, 3

• Men with uncomplicated lower UTI: All UTIs in men are classified as complicated; prescribe a minimum of 7 days of therapy regardless of the agent chosen. 5, 6

Urine Culture Indications

• Obtain a urine culture with susceptibility testing before initiating antibiotics when:

  • The patient has recurrent UTI (≥2 episodes in 6 months or ≥3 in 12 months). 1, 2
  • Symptoms do not resolve by the end of treatment or recur within 2 weeks. 1, 2
  • The patient presents with atypical symptoms or has a history of resistant isolates. 1, 2
  • The patient is male (all male UTIs warrant culture). 6
  • The patient is pregnant. 1, 2

• Do not obtain a urine culture in women with typical symptoms of uncomplicated cystitis (dysuria, frequency, urgency) and no risk factors for resistance, because empiric treatment is appropriate and culture adds minimal diagnostic value. 1, 6, 7

Hematuria-Specific Counseling

• Microscopic or mild gross hematuria accompanying acute UTI symptoms (dysuria, frequency, urgency) does not require additional imaging or urologic referral when the patient is <35 years old, has no risk factors for malignancy (smoking, occupational chemical exposure, chronic indwelling catheter), and hematuria resolves after treatment. 1, 8

• Instruct the patient to return for further evaluation if hematuria persists beyond 6 weeks after completing antibiotic therapy, because persistent hematuria warrants imaging (CT urography or ultrasound) and cystoscopy to exclude malignancy or urolithiasis. 1, 8

• Gross hematuria in adults >35 years or with risk factors for malignancy requires prompt urologic referral even when UTI is present, because the association with malignancy is 30–40% and infection does not exclude concurrent pathology. 1, 8

Follow-Up Plan

• No routine follow-up urinalysis or urine culture is needed for asymptomatic patients whose symptoms resolve by the end of treatment. 1, 2

• Schedule follow-up within 48–72 hours if:

  • Symptoms do not improve or worsen despite therapy (consider imaging to rule out obstruction, stones, or abscess). 1, 5
  • Fever develops or persists beyond 72 hours (suggests pyelonephritis requiring extended therapy or parenteral antibiotics). 1, 5

• For women whose symptoms resolve but recur within 2 weeks, obtain a urine culture and prescribe a 7-day regimen of a different antibiotic, assuming resistance to the initial agent. 1, 2

Patient Education and Self-Care

• Advise increased fluid intake (though evidence for preventing UTI is limited, it may help flush bacteria and relieve dysuria). 6

• Recommend cranberry products or methenamine hippurate for recurrent UTI prevention in patients with ≥2 episodes in 6 months, as these have modest efficacy without promoting resistance. 6

• Counsel patients to return immediately if they develop fever >38.3°C, flank pain, nausea/vomiting, or inability to tolerate oral intake, because these symptoms indicate pyelonephritis requiring urgent evaluation and possibly parenteral therapy. 1, 2

Common Pitfalls to Avoid

• Do not treat asymptomatic bacteriuria (positive culture without symptoms), because treatment offers no benefit and promotes resistance; exceptions are pregnancy and patients undergoing urologic procedures with anticipated mucosal bleeding. 1, 2

• Do not use nitrofurantoin when creatinine clearance is <30 mL/min, because urinary concentrations are insufficient and pulmonary toxicity risk is higher. 5

• Do not prescribe a 3-day course of nitrofurantoin, because this duration is associated with higher failure rates; the minimum effective duration is 5 days. 1, 3

• Do not assume hematuria is solely due to infection in patients >35 years or with risk factors; arrange urologic evaluation after infection treatment to exclude malignancy. 1, 8