Urinary tract infection Flashcards
How common is it?
Reason for 1-3% of GP consultations.
1.56% incidence for men and 9.22% incidence for females.
Asymptomatic bacteriuria is also more common in female’s vs males.
Who does it affect?
About 1 in 3 women will have a UTI by 24 years of age. About 1 in 2 will be treated for a symptomatic one during their lifetime.
What causes it?
Bacteria from the GI tract. E. coli accounts for 80%, others include Staphylococcus species, Proteus mirabilis, and enterococci.
Candida albicans rarely causes UTI. When it does, it is usually in hospitalized people with risk factors such as indwelling catheter, immunosuppression, diabetes mellitus, or antibiotic treatment.
3 classifications: Retrograde, ascending through the urethra into the bladder. Via the blood stream (more likely in immunocompromised people). And direct, for example upon insertion of a catheter into the bladder, instrumentation, or surgery.
What risk factors are there?
Most UTIs are not associated with a risk factor.
Sexual intercourse – common risk factor for younger women.
Atrophic urethritis and vaginitis (in postmenopausal women).
Abnormalities of UT function (for example indwelling catheter, neuropathic bladder, vesicoureteric reflux, outflow obstruction, anatomical abnormalities, significant asymptomatic bacteriuria).
Incomplete bladder emptying.
Female diaphragm, spermicide coated condoms.
Previous UT surgery.
Immunocompromised.
How does it present?
Urinary frequency, urgency, and/or strangury (the feeling of needing to pass urine despite having just done so).
Dysuria.
Urine that is offensive smelling, cloudy, or contains blood.
Constant lower abdominal ache.
Non-specific malaise, such as aching all over, nausea, tiredness and cold sweats.
Urge incontinence.
Typical features may be absent in frail, elderly women in nursing homes (catheterized and non-catheterized), and it is important to exclude other sources of infection.
However, the presence of one of the following indicates a UTI: New costovertebral tenderness, rigors, new onset delirium, fever greater than 37.9 or 1.5 above the baseline.
Signs on examination?
Suprapubic tenderness. Loin pain and fever may be an upper urinary tract infection (i.e. Pyelonephritis).
Investigations
Dipstick, look for leukocytes and nitrate. If both negative, UTI is unlikely. If the leukocyte test alone is positive, a UTI is moderately likely. If the nitrate test is positive, with or without a positive leukocyte esterase test, a UTI is highly likely.
Urine cultures for sensitivity.
Treatment
In women, 3-day antibiotic course. Nitrofurantoin 50mg four times daily orally, or 100mg twice daily or, Trimethoprim 200mg twice daily.
If the women has been treated with trimethoprim up to a year previously, consider nitrofurantoin.
Consider a longer course if they have impaired renal function, an abnormal urinary tract and is immunosuppressed.
7-day course for men.
Conditions that would present similarly
Pyelonephritis (especially if fever loin pain).
Urethral syndrome/painful bladder syndrome/intestinal cystitis if symptoms are relieved by voiding and aggravated by drinking alcohol or drinks containing caffeine.
Drug induced cystitis in women treated with cyclophosphamide, allopurinol, danazol, or tiaprofenic acid.
Atrophic vaginitis/urethritis if a menopausal woman has vaginal discharge or itch, and pain during sex.
Threadworms.
Cervicitis, urethritis or vaginitis.
Urological cancer, especially recurrent, with haematuria and infection not confirmed.
Epididymitis and acute prostatitis in men.
