Recurrent urinary tract infection
By Dr Vaishini
By definition, it has 2 episodes with acute bacterial cystitis, along with associated symptoms within the last 6 months or 3 episodes within a year. Recurrent UTIs are more common in females.
Traditionally, UTI has been defined as >100,000 colony forming units (CFU)/ml of urine associated with typical acute symptoms of dysuria, urgency, increased frequency, or suprapubic pain. However, more than 100 CFU of E. coli with typical acute urinary symptoms has a positive predictive value of about 90%, suggesting that a lower CFU threshold may be more appropriate in diagnosing simple and recurrent UTIs.
There are several conditions that may predispose to an increased risk of UTIs in both genders.
|Anatomical defects that lead to stasis, obstruction, urinary reflux all result in an increased predisposition to recurrent urinary tract infections.
|Vesicoureteric reflux (VUR) is identified in up to 40% of children being investigated for a first UTI.
|Cystoceles and pelvic organ prolapse are important risk factors for recurrent UTIs in women
|Functional defects, like overactive bladder and urinary incontinence
|Sexually active women without any identifiable structural abnormality or another predisposing condition.
|Older men can often develop urinary tract infections due to outflow obstruction or neurogenic bladder resulting in urinary stasis and an increased risk of recurrent infection.
|Several other lesions may predispose to recurrent UTIs, including intraluminal (bladder stones, neoplasms, indwelling catheters, stents, foreign bodies), intramural (ureteral stenosis/strictures), and extramural lesions (inflammatory mass, fibrosis, extrinsic mass effect, or neoplasm).
However, immunodeficiency typically does not lead to isolated recurrent UTIs.
Risk Factors for Recurrent Infections include:
- Any spermicide use within the previous year, especially if used with a diaphragm
- Atrophic vaginitis
- Chronic diarrhea
- First UTI when young (prior to 16 years of age)
- Genetic predisposition (usually through bacterial/vaginal mucosal adherence factors)
- Higher frequency of sexual intercourse
- Increased post-void residual urine (incomplete bladder emptying)
- Inadequate fluid intake (low urinary volumes)
- New or multiple sexual partners
- Mother with a history of frequent or multiple UTIs
- Urinary incontinence
- Use of spermicide coated condoms
Personal Hygiene Factors:
|Not washing hands before wiping vaginal area after voiding
|Taking baths instead of showers
|Wiping and washing the vaginal area (incorrectly) from back to front
|Not using clean, soft washcloths to clean the vaginal area when washing
|Not cleaning bladder opening area first when washing
|Vulva atrophic, not using vaginal estrogen, when appropriate, in postmenopausal women
How to manage UTI ?
The typical patient with recurrent UTIs does not require either cystoscopy or any urological imaging.
In women with a history of recurrent UTI who present with typical symptoms, no further urological evaluation is necessary other than a urine culture and sensitivity, even though the diagnosis of recurrent cystitis can be made clinically.
Urine cultures should be performed in the setting of a severe infection or high risk of antibiotic resistance (multidrug-resistant isolate; recent inpatient admission; recent antibiotic use; a history of travel to India, Israel, Spain, or Mexico). Urine cultures are also necessary to differentiate recurrent infections (repeat infections with different organisms) from relapsing (identical organisms on culture). Relapsing infections suggest a persistent source of bacterial inoculation, such as an abscess, chronic bacterial prostatitis, or an infected stone.
Urological imaging is advised for only a select group of women. Indications for urological imaging include relapsing infections, persistent hematuria after treatment; a history of stone passage; or repeated isolation of Proteus from the urine, which is often associated with renal stones. Preferred imaging modalities include renal ultrasonography or, ideally, a CT scan of the abdomen and pelvis.
Treatment for Recurrent UTI:
- Maximizing personal hygiene factors, avoiding spermicides, wiping correctly, using vaginal estrogens if appropriate, etc.
- Cranberries are thought to work by providing proanthocyanidins which decrease bacterial adherence to the urothelium.
- Prophylactic methenamine has been suggested, along with vitamin C, to help acidify the urine.
- Antibiotic prophylaxis has been quite successful in controlling recurrent UTIs, but using alternative means first is preferable. However, prophylaxis is never appropriate in patients who have permanent catheters or nephrostomies as this will rapidly lead to highly resistant organisms.
- Post-coital prophylaxis is appropriate for women with frequent episodes of cystitis that are clearly associated with sexual activity.
- Continuous prophylaxis with long term and low dose. Initial evaluation of the effectiveness of prophylaxis is suggested at three months. If effective, a six to twelve-month duration is typical.