Complicated urinary tract infection
UTI in patients with anatomical or functional abnormalities of the urinary tract, immunosuppression, catheterization, male sex, or pregnancy. Empirical therapy covers E. coli, Klebsiella, and Pseudomonas, accounting for local resistance.
ICD-10 N103 drugs
Also known as: Acute pyelonephritis, Healthcare-associated UTI
Drugs used for this condition
- AMeropenemSecond line · Carbapenem antibiotic for intravenous useComplicated urinary tract infections appear in the AEMPS Archifar label. Complicated means infection over a stone, a stent, a catheter, a neurogenic bladder, prostatic enlargement or after a urological procedure, and the flora there is more often resistant. Meropenem is picked after culture, when an extended-spectrum beta-lactamase producer grows or the patient has just failed a cephalosporin and a fluoroquinolone. Plain cystitis in a healthy woman needs no carbapenem: fosfomycin, nitrofurantoin and trimethoprim do the work. Once the patient improves and the isolate is susceptible, intravenous meropenem steps down to a narrow oral agent, which shortens the hospital stay and eases resistance pressure.
- BCiprofloxacinFirst line · Fluoroquinolone antibacterialsAn option for complicated urinary tract infection and pyelonephritis in adults guided by culture and confirmed susceptibility, not an empiric first-choice agent. Empiric fluoroquinolones fit only where local E. coli resistance stays below 10% (IDSA/ESCMID). In Spain, E. coli fluoroquinolone resistance often exceeds that threshold (SEIMC data). Guidelines therefore favor parenteral ceftriaxone or another alternative until culture results return. The FDA warns of serious adverse effects.
- BGentamicinSecond line · Aminoglycoside antibioticGentamicin is used for complicated UTI and acute pyelonephritis requiring parenteral therapy as an alternative to third-generation cephalosporins and fluoroquinolones. Advantages include activity against Pseudomonas and ESBL producers in some regions. IDSA 2010 includes aminoglycosides in complicated UTI regimens in groups at risk of resistance. After clinical response within 48–72 hours, switch to an oral agent guided by susceptibility.
How to read tiers A–F
Evidence tiers belong to the drug-indication pair, not to the drug as a whole: the same substance can be A for one condition and F for another.
- AStrong evidence – first or second line in international guidelines
- BRecommended in selected cases
- CStudy data contradict each other
- DBenefit not proven, no documented harm
- FDocumented harm, or risk without benefit