Acute Pyelonephritis

Clinical definition:

Bacterial infection of the kidney commonly presenting in women ages 18 – 40 years. Common symptoms include high fever, chills or rigors, costovertebral tenderness, and flank pain. Common etiologies include the enterobacteriales, E. coli, K. pneumoniae, and P. mirabilis. P. aeruginosa and Enterococci are less common causes.


Preferred antibiotic choice(s)for mild-moderate cases
Ciprofloxacin (PO)Oral liquid: 250 mg/5 mL (anhydrous); Tablet: 250 mg (as hydrochloride)500 mg 12 hourly7 days
For severe cases consider:
Gentamicin (IV)Injection: 10 mg; 40 mg (as sulfate)/ mL in 2- mL vial5 mg/kg daily7 days
Amikacin (IV)Injection: 250 mg (as sulfate)/mL in 2- mL vial15 mg/kg daily7 days
Ceftriaxone (IV)Powder for injection: 250 mg; 1 g (as sodium salt) in vial1 g daily7 days
Cefotaxime (IV)Cefotaxime- Powder for injection: 250 mg per vial (as sodium salt1 g 8 hourly7 days

Principles of Stewardship:

  • Obtain urine and blood cultures for bacterial identification and conduct antimicrobial susceptibility testing (AST) prior to starting antibiotic therapy.
  • If treating Pseudomonas infection with ciprofloxacin, increase dose to 750 mg and treat 12 hourly.


  • Avoid treatment with aminoglycosides in patients with renal impairment.