Signs and symtoms (fever with no other source is the most common; patient's may also have suprapubic or flank pain) AND pyuria (>5-10 WBC/hpf or >27 WBC/microliter) AND positive urine culture ≥100,000 colonies)


Patients with chronically indwelling catheters will almost universally have positive urine cultures.

Typically, catheterized patients will become colonized within 48 hrs of catheterization.