NHS Fife Microbiology laboratories receives approximately 70000 urine specimens per annum requesting culture. Many of the requests indicate the test was sent because of a positive dipstick test in a catheterised patient.


Assessment
Clinical staff are not using the limited NHS resources wisely by performing dip stick tests on urine from catheterised patients. This practice also puts patients at risk of unnecessary antibiotic exposure and thus C. difficile infection / bacterial resistance.

Recommendations
1. Nursing staff and medical staff must only send or request urine for culture from catheterised patient when they have symptoms of a urinary tract infection. A positive dip stick test plays no role in the diagnosis.
2. Microbiology will not t process specimens from catheterised patients where the clinical signs and symptoms are not provided as part of the request. i.e. specimens were the clinical details indicate “possible infection” or some other non-specific comment will not be processed.
3. Staff should follow SIGN guidance (SIGN 88) for managing patients with suspected catheter-related UTI - http://www.sign.ac.uk/pdf/sign88.pdf (see extract below):

The guidance highlights under section 6: Management of bacterial UTI in patients with catheters


6.1 Diagnosis............In catheterised patients who present with fever:

  • Look for associated localising (loin or supra-pubic tenderness) or systemic features
  • Exclude other potential sources of infection
  • Send off an appropriately taken urine sample for culture to determine the infecting organism and susceptibility to antibiotics
  • Consider antibiotic therapy taking into account the severity of the presentation and any comorbid factors.
  • Only send urine samples for laboratory culture if the patient has clinical sepsis, not because the appearance or smell of the urine suggests that bacteriuria is present.

6.2.2 dipstick tests

Symptomatic UTI cannot be differentiated from asymptomatic bacteriuria on the basis of urine analysis with dipstick tests. Pyuria is common in catheterised patients and its level has no predictive value. There is no evidence to suggest that detecting pyuria by urine analysis is of any value in differentiating symptomatic UTI from asymptomatic UTI (bacteriuria) in catheterised patients. Therefore, do not use dipstick testing to diagnose UTI in patients with catheters.


For further information please contact:


Keith Morris FRCPath, FRCP(Edin)
Consultant Microbiologist & Infection Prevention Doctor
North Laboratory
Victoria Hospital
Hayfield Road
Kirkcaldy
Fife
KY2 5AG

Tel 01592 643355 x27917