Inclusion Criteria:

• Men or non-pregnant women, 18 years of age or older with a suspected complicated urinary tract infection with an onset of symptoms 72 hours or less prior to study entry
• Women of childbearing potential using reliable birth control
• Patients must present with a least one sign or symptom of a lower UTI (dysuria, urgency, frequency, suprapubic pain) or for spinal cord injury patients if such symptoms are not present, at least one of the following: fever (T > 38º C or 100.4º F orally), onset of urinary incontinence, increased spasticity, autonomic hyperreflexia, increased sweating, or cloudy and odorous urine.

• Patients must have at last one of the underlying conditions

  • Indwelling urinary catheter or intermittent catheterization
  • 100 mL of residual urine after voiding
  • Neurogenic bladder
  • Obstruction due to nephrolithiasis, tumor or fibrosis
  • Urinary retention due to benign prostatic hypertrophy, bladder cancer or other urological anatomic abnormalities
  • Patients must have pyuria prior to enrollment (within 48 hours) defined as > 10 leukocytes/mm3 in unspun urine by hemocytometer or > 5 leukocytes/hpf in resuspended sediment of centrifuged urine

  • Patients must have one clean-catch, midstream urine culture or culture from catheter (obtained using sterile technique, not from a Foley bag) that was obtained within 48 hours of enrollment and had a positive results:

    1. Defined as >= 100000 CFU/mL (>= 10000 CFU/mL for S. saprophyticus) for a causative pathogen
    2. If more than 1 pathogen is identified, each should be present at a colony count >= 100000 CFU/mL (>= 10000 CFU/mL for S. saprophyticus) to be included in the analysis
    3. For catheterized patients two or more pathogens (>= 100000 CFU/mL) (>= 10000 CFU/mL for S. saprophyticus) isolated from a baseline urine culture will be considered contaminants unless simultaneous blood culture yields the same pathogen(s)
    4. The causative pathogen must be susceptible to ciprofloxacin on in vitro susceptibility testing
    5. Enrollment and start of treatment is permitted prior to the availability of the culture report

Exclusion Criteria:

• Have a history of allergy to quinolones
• Are unable to take or inability to tolerate oral medications
• History of prostatitis or epididymitis
• Have signs and symptoms of pyelonephritis [all of the following: fever (T>38° C/100.4° F orally), chills, and flank pain or costovertebral angle tenderness]
• Have an intractable infection requiring > 14 days of therapy
• Have an uncomplicated UTI
• Have a renal transplant
• Have ileal loops or vesico-ureteral reflux
• Have a ciprofloxacin-resistant pathogen upon urine or blood culture
• Have received systemic antimicrobial therapy within 48 hours prior to enrollment
• Have a neutrophil count <1000/mm3, CD4 < 200/mm3 or other conditions associated with significant depression in host defense; HIV testing is not mandatory
• Have a requirement for concomitant systemic antibacterial therapy with agents not specified in this protocol
• Have significant liver impairment (baseline SGOT or SGPT and/or total bilirubin greater than 3 times the upper limit of normal)
• Have significant renal impairment (serum creatinine > 3.0 mg/dl or creatinine clearance < 30 mL/min/1.73 m2)
• Have a history of tendinopathy associated with fluoroquinolones
• Are pregnant, nursing or in whom pregnancy cannot be excluded or unreliable contraception is being used
• Have been diagnosed with a rapidly fatal underlying disease (death expected within 6 months)
• Have a requirement for concomitant administration of sucralfate or divalent and trivalent cations such as iron or antacids containing magnesium, aluminum or calcium
• Have been previously enrolled in this clinical study
• Have been taking an investigational drug in the last 30 days
• Have a history of a UTI or bacteruria with a urinary pathogen resistant to a fluoroquinolone within 6 months prior to current UTI episode
• Any of the following signs of sepsis:
• Systolic blood pressure < 90mm or a decrease of > 40mm from baseline
• Hypothermia (T< 35.6°C, core)
• Unexplained metabolic acidosis (pH < 7.3 with BE >= 5mmol/L or elevated lactate level)
• PaO2 < 75 mm/Hg on room air or PaO2 /FIO2 ratio < 250
• Acute renal failure (urine output < 0.5mL/kg/h for >= 1h)
• DIC ( PTT, PT, or platelets < 1/2 baseline or < 100,000)
• Acute deterioration in mental state
• Hemodynamic state (CI > 4L/min/m2 + SVR < 800 dyn-sec/cm-5)15