UTIs (urinary tract infections) are common infections. In recent years there have been revised recommendations about the need to carefully interpret laboratory results and use antibiotics only when needed.
The emergence of antibiotic resistance has meant care with use of antibiotics is the responsibility of all doctors and nurses. The Royal College of General Practitioners and Public Health England’s Primary Care Unit have both recommended care with interpretation of urine results and responsible use of antibiotics for treatment. It is also recommended that to help prevent UTI, maintenance of hydration is important.
Care must be taken when urine samples are taken. The specimen should be mid-stream. Refrigeration of specimens or use of specimen pots with boric acid will prevent bacterial overgrowth and a false positive result. Culture results must be interpreted correctly as usually a single or predominant organism will be present if significant.
If it is likely a patient has a UTI, Public Health England (PHE) recommend using the antibiotic nitrofurantoin as first line treatment (if the patient’s renal function is normal). This antibiotic is recommended because resistance to amoxicillin and trimethoprim are increasing. Trimethoprim is recommended if there is a low risk of resistance. Women are treated for 3 days and men for 7 days.
PHE state that risk factors for increased antibiotic resistance include: care home resident, recurrent UTI, hospitalisation for more than 7 days in the last 6 months, unresolving urinary symptoms, recent travel to a country with increased antibiotic resistance (outside Northern Europe and Australia) especially health related, previous known resistant UTI. If there is an increased resistance risk, it is recommended to send a culture for antibiotic sensitivity testing.
In any person aged > 65 years, the presence of bacteria in urine alone, is common but is not associated with increased illness. Treatment is started only in the presence of symptoms.
If the patient has a catheter, antibiotics will not eradicate bacteria in urine. The patient is only treated if unwell or pyelonephritis (loin pain and fever) is likely. The latest national guidance is not to use prophylactic antibiotics for catheter changes, except for patients with UTIs associated with a catheter change. This again is in line with the plan to limit over-use of antibiotics.
Once started on antibiotic therapy the urine infection should respond. If however, the patient doesn’t respond, or develops fever, loin pain then they should seek medical attention. It may be that the antibiotic prescribed isn’t effective against the bacteria causing the infection and so will need to be changed. The medical practitioner may send a urine sample to the microbiology laboratory (if not previously sent) to identify which antibiotics are effective against the bacteria causing the current infection.
This is a brief guide on key issues in management of UTIs with particular reference to primary care. Pregnant ladies and children have not been discussed above.
Dr. Faisal bin-Reza
BMedsci MBBS DTM&H MRCP MSc FRCPath
The Princess Alexandra Hospital NHS Trust