Although antibiotic-susceptible E. coli is responsible for more than 80 percent

The initial empiric therapy for these patients should include an agent with a broad spectrum of activity against the expected uropathogens. Treatment most often includes a fluoroquinolone, administered orally if possible. In patients who are unable to tolerate oral medication or who require hospitalization for concomitant medical problems, appropriate initial therapy may be parenteral administration of one of the following: a thirdgeneration cephalosporin with antipseudomonal activity such as ceftazidime or the combination of an antipse- udomonal penicillin (ticarcillin) with an aminoglycoside.

Patients with complicated UTIs require at least a 10- to 14 day course of therapy. Follow-up urine cultures should be performed within 10 to 14 days after treatment to ensure that the uropathogen has been eradicated. Patients initially placed on parenteral therapy can be switched to oral therapy within 72 hours as long as they are clinically improving and able to tolerate the oral agent, and a regimen is available that covers the identified pathogen(s).