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Acute upper urinary tract infection (pyelonephritis/urosepsis) or catheter-associated infection (Antimicrobial)


In catheterised patients, treat infection based on clinical signs and symptoms of urinary-tract origin.  Send urine for culture only if infection strongly suspected and include symptom details (not dipstick results) on the Microbiology request form.  Long term catheters should be changed after starting antibiotic treatment. See NHS Highland Control of Infection Policy for Indwelling Urethral Catheter Insertion and Management.

Send urine sample to bacteriology before treatment commences. If no response in 24 hours consider hospital admission.

The European Medicines Agency's Pharmacovigilance Risk Assessment Committee has recommended restricting the use of fluoroquinolone antibiotics following a review of disabling and potentially long-lasting side effects mainly involving muscles, tendons, bones and the nervous system (press release October 2018), but they are an option in acute pyelonephritis, which is a severe infection.

For management of kidney transplant patients, immunocompromised patients and known or suspected infections with multi-drug resistant pathogens including ESBLs, contact Microbiology for discussion of treatment options.

For glossary of terms see Glossary.

Discuss antimicrobial cover for urinary catheter exchange in a patient with a recent joint replacement with Microbiology.

Drug details

For moderate illness with systemic upset not requiring hospital admission.

Co-amoxiclav 625mg, 3 times daily

7 days

In penicillin allergy (beware of side effect risk, see notes above)

Ciprofloxacin 750mg, twice daily (see BNF warnings and MHRA Drug Safety Alert). When sensitivities are known, suitable oral agents include amoxicillin, cefalexin and trimethoprim, in addition to those recommended above.

7 days

For severe infection (hospital treated)

Mandatory review of gentamicin following culture and sensitivity information.

Check SCi Store for urinary pathogens isolated in last 6 months not covered by gentamicin or aztreonam and seek advice from Microbiology.

IV gentamicin - refer to NHS Highland gentamicin dosing guidelines.

7 to 14 days

In severe renal impairment (CrCl less than 10ml/min) or renal replacement therapy or where gentamicin unsuitable. Review dose if renal function improves.

IV aztreonam 1 gram stat then 250mg 3 times daily.

7 to 14 days

When switching to oral therapy without positive microbiology results

Follow recommendations for moderate illness.

For infections arising within 24 hours of surgery where gentamicin has been given as part of surgical prophylaxis

Substitute IV aztreonam 2g every six hours for gentamicin.

Last reviewed: 25/08/2022

Next review date: 25/08/2025

Author(s): Antimicrobial Management Team.

Version: 2

Approved By: TAM Subgroup of ADTC

Reviewer name(s): Area Antimicrobial Pharmacist.

Document Id: AMT180