Send Feedback

Print

Mobile

 Back

CDHB

Lower Urinary Tract Infections

• Cystitis is the syndrome of frequency and dysuria. Other lower urinary tract symptoms may, or may not, be present. As many as one-half of all women with this syndrome do not have a bacterial infection and are considered as having non-bacterial cystitis (urethral syndrome). The aetiology of the latter is multifactorial, but chlamydia trachomatis urethritis should be excluded.
• Bacterial cystitis and asymptomatic bacteriuria - patients with bacterial cystitis will have typical lower urinary tract symptoms together with pyuria.

  All pregnant women should be screened in each trimester for (asymptomatic) bacteriuria. Only about one-half of pregnant asymptomatic women with bacteriuria will also have pyuria (>10 x 10⁶ WBC/L) indicating urinary tract inflammation. The prevalence is 5-6% in Caucasian women and 15-18% in Maori/Polynesian women. These women are at risk of developing acute pyelonephritis in the last trimester or puerperium. E. coli is the commonest pathogen followed by Staphylococcus saprophyticus (more prevalent in the spring and summer months) and Proteus mirabilis.

Diagnosis

• The diagnosis is confirmed by culturing a mid-stream urine (MSU) specimen.
• When interpreting the number of bacterial colony forming units/L of urine (cfu/L) of any uropathogen, you will need to take into account the presence/absence of pyuria (epithelial cells indicate contamination) and symptoms, regardless of the patient's gender.

Investigations

• Always consider the question - "Is this infection a pointer to some underlying abnormality in the urinary tract?"
• In general the indications for investigations in adult men with urinary tract infection are no different from those for women. A urine flow rate measurement may be appropriate in males with any prostatic symptoms.
• Adults with a UTI only require organ imaging of the urinary tract (usually urinary tract ultrasonography) if:
  • They had urinary tract infections/symptoms prior to the commencement of sexual activity.
  • They have acute pyelonephritis that has an atypical clinical course.
  • The infections have become closely-spaced.
  • Proteus species or an unusual organism is present.
  • Microscopic haematuria or pyuria persists, or
  • Therapy has failed.
  • They have a history of kidney stones or symptoms suggesting renal colic.

Management of Lower Urinary Tract Infections

• For treatment of a lower urinary tract infection a single dose of an appropriate antimicrobial agent is as effective as a conventional 3 day course of the same drug. Because of the increasing incidence of bacterial resistance, trimethoprim may no longer be appropriate.

  Suggested regimens are:

Drug Guidelines for Cystitis

• Follow-up - all patients should have a urine specimen taken for culture 7-14 days after completing treatment.

Prophylactic Treatment for Patients with Recurrent Urinary Tract Infections

• Patients with recurrent UTIs (e.g., >3 in 6 months) with normal renal function and a normal urinary tract merit consideration for prophylactic antimicrobial therapy.
• Try simple measures - increase fluid intake, increase frequency of micturition. In women, also consider treatment of cervical erosion or vaginitis, post coital voiding, application of an antiseptic cream to the periurethral area prior to intercourse.
• Drugs which have been shown to be effective in prophylactic regimens include:
  • Nitrofurantoin 50 mg or trimethoprim 150 mg (preferred agents), or norfloxacin 200 mg nocte.

  The above drugs should be taken after emptying bladder and before retiring. If patients have renal insufficiency, cefaclor 250 mg can be used for prophylaxis.

• Prophylactic treatment should be started only after a UTI has been treated with a curative course of therapy and the post-treatment culture is sterile. Prophylactic treatment should be continued for at least 3 and preferably for 6-12 months, although the patient may wish to continue for longer.
• Nitrofurantoin prophylaxis - 0.5% of patients treated will get a pulmonary reaction. Warn the patient to report any new respiratory symptoms.
• A prophylactic antibiotic on alternate nights, 3 nights a week or after intercourse may be equally efficacious.
• In post menopausal women, atrophic vaginitis should be considered and treated appropriately, e.g., intravaginal oestrogens.

Topic Code: 2742