Management of Urinary Tract Infections
First-Line Antibiotic Treatment for Uncomplicated Cystitis
For acute uncomplicated cystitis in women, use nitrofurantoin for 5 days, trimethoprim-sulfamethoxazole (TMP-SMX) for 3 days if local resistance is <20%, or fosfomycin as a single 3-gram dose. 1, 2
Nitrofurantoin is the preferred first-line agent due to consistently low resistance rates (approximately 2%) and minimal collateral damage to normal flora. 1, 3
TMP-SMX should only be used when local resistance rates are documented to be <10-20%, as resistance now approaches 18-22% in many U.S. regions and is associated with poorer clinical outcomes. 1, 4
Fosfomycin offers the advantage of single-dose therapy and maintains low resistance rates, making it an excellent alternative when compliance is a concern. 1, 2
Avoid fluoroquinolones as first-line therapy - reserve these as second-line agents due to increasing resistance rates and the need to preserve their efficacy for more serious infections. 1, 3
Treatment duration should be as short as reasonable, generally no longer than 7 days for uncomplicated infections. 1
Management of Uncomplicated Pyelonephritis
For uncomplicated pyelonephritis, use oral fluoroquinolones (ciprofloxacin 500-750mg twice daily for 7 days or levofloxacin 750mg daily for 5 days) when local resistance is <10%. 2, 5
In areas with higher fluoroquinolone resistance, initiate treatment with a single dose of parenteral ceftriaxone followed by oral therapy. 2
Third-generation cephalosporins are preferred when fluoroquinolone resistance is a concern or in pregnant patients. 6
Levofloxacin 750mg daily for 5 days is FDA-approved for acute pyelonephritis caused by E. coli, including cases with concurrent bacteremia. 5
Complicated UTIs and Multidrug-Resistant Organisms
For complicated UTIs, treat for 7-14 days (14 days for men when prostatitis cannot be excluded), with antibiotic selection based on culture results and local resistance patterns. 1, 2, 7
Treatment duration for multidrug-resistant organisms does not need to be extended beyond standard durations for the anatomical location, provided the antimicrobial demonstrates activity against the organism and source control is achieved. 1
For ESBL-producing Enterobacteriaceae causing mild-moderate UTIs, alternatives to carbapenems include nitrofurantoin, fosfomycin, cefoxitin, or piperacillin-tazobactam based on susceptibility results. 3
For carbapenem-resistant Enterobacteriaceae (CRE), treatment options include ceftazidime-avibactam, colistin, polymyxin B, fosfomycin, or aminoglycosides. 3
Asymptomatic Bacteriuria: When NOT to Treat
Do not treat asymptomatic bacteriuria in non-pregnant patients, as treatment provides no benefit and increases antimicrobial resistance. 1, 7
The only two populations requiring treatment of asymptomatic bacteriuria are: pregnant patients and those undergoing invasive urologic procedures with expected mucosal bleeding. 1
For pregnant patients with asymptomatic bacteriuria, treat for 3-5 days depending on the antimicrobial used, not exceeding the duration used for symptomatic cystitis. 1, 2
For patients undergoing invasive urologic procedures, a single dose of preoperative prophylaxis is sufficient in most cases. 1
Avoid surveillance urine testing in asymptomatic patients with recurrent UTIs, as this leads to unnecessary treatment. 1, 7
Recurrent UTIs: Diagnosis and Prevention
For recurrent UTIs (≥2 infections in 6 months or ≥3 in one year), obtain urine culture with each symptomatic episode before initiating treatment. 1, 7
Vaginal estrogen therapy is strongly recommended for postmenopausal women to prevent recurrent UTIs and may reduce infection frequency. 2, 7
Methenamine hippurate reduces recurrent UTI episodes in women without urinary tract abnormalities and serves as a non-antibiotic alternative. 2, 7
Daily antibiotic prophylaxis with nitrofurantoin is the most effective prevention strategy, reducing UTI rate to 0.4 per year, but should be balanced against antimicrobial stewardship concerns. 7
Increased fluid intake may reduce recurrent UTI risk in premenopausal women. 2
Post-coital antibiotic prophylaxis within 2 hours of sexual activity may be considered for premenopausal women with infection patterns clearly linked to intercourse. 7
Antimicrobial Stewardship Principles
Deescalate antibiotics based on culture results whenever possible, and prefer oral regimens over intravenous therapy as they show comparable outcomes with reduced adverse events. 1, 2
Oral antimicrobial therapy is the primary approach for uncomplicated UTIs and should be used instead of IV therapy when clinically appropriate. 2
Multiple randomized trials demonstrate that all-oral or mostly-oral regimens result in comparable outcomes to IV-only treatment while reducing hospital length of stay and catheter-related complications. 1
Obtain urine culture before initiating antibiotics in patients with recurrent UTIs to enable targeted therapy and track resistance patterns. 1, 7
Use prior culture data when available to guide empiric therapy for acute episodes while awaiting new culture results. 7
Critical Pitfalls to Avoid
Do not diagnose UTI based solely on positive urine culture without corresponding symptoms - this represents asymptomatic bacteriuria and should not be treated. 1, 6
Do not use broad-spectrum antibiotics for extended durations when narrower-spectrum agents are effective based on culture results. 1, 7
Do not prescribe fluoroquinolones empirically when first-line agents are appropriate, as this accelerates resistance development. 1, 3
For persistent symptoms despite treatment, obtain repeat urine culture before prescribing additional antibiotics rather than empirically escalating therapy. 7
Ensure adequate source control (e.g., removing or changing catheters when feasible, addressing urological abnormalities) as antibiotics alone may be insufficient for complicated UTIs. 1, 7