Urinary tract infections
Last updated: 2013-04-04 © Duodecim Medical Publications Ltd
Quick Reference 
Urinary tract infection in a child 
- Symptoms reveal the level of the urinary tract infection (UTI).
- Cystitis: urinary frequency, urinary urgency, burning on urination
- Pyelonephritis: fever, back or flank pain, CRP > 40 mg/l
- In a basically healthy woman aged 18 to 65 years, an occasional cystitis can be diagnosed on grounds of typical symptoms (using e.g. a structured telephone interview) without any laboratory tests provided that history, symptoms or signs do not suggest a sexually transmitted disease or other gynaecological infection.
In other patients with suspected cystitis and in all patients with suspected pyelonephritis, the diagnosis must be based on symptoms and bacterial culture of the urine
- If the symptoms are atypical, chemical dipstick screening or standard particle counting can be used to support the diagnostics.
- Post-treatment follow-up cultures are only needed if symptoms do not resolve and always during pregnancy.
- A UTI is treated according to the level of infection.
- Cystitis is treated with an antimicrobial drug for 3 days in women and 7 days in men.
- Pyelonephritis is treated for 7 to 10 days with an antimicrobial drug that has high penetration into renal tissue.
- Dysuria, increased urinary frequency and urgency in the absence of bacteriuria
- If the urine tests positive for white blood cells but the bacterial culture is negative, testing for chlamydia should be considered, particularly in young patients.
- If no infection is diagnosed, a gynaecological examination should be carried out or the patient referred to a urologist (cystoscopy; urethral dilation may be helpful; interstitial cystitis  ).
- In postmenopausal women, topical oestrogens may be of benefit.
- In some patients, oxybutynin or tolterodine may be helpful in the treatment of recurrent symptoms.
- 85% will recover spontaneously with time.
Other diseases to be taken into account
- Sexually transmitted diseases
- Gynaecological infections 
- Prostatitis  
- Syndroma pelvis spastica 
- Only in pregnant women should asymptomatic bacteriuria be screened for and treated [B] .
- Advancing age, diseases and functional disability increase the prevalence of asymptomatic bacteriuria.
- Affects up to 0.5% of men, 1–4% of girls and 5–10% of women.
- In long-term care facilities it affects 30% of men and 50% of women.
Cystitis in female patient
- It is not necessary to collect a urine specimen
in occasional acute cystitis of a woman aged 18 to 65 years if the clinical picture is unambiguous.
- Point of care tests can be used to confirm the diagnosis in clinically unclear cases.
- Narrow-spectrum antimicrobial drugs (trimethoprim, nitrofurantoin, pivmecillinam) are the primary choice
. Duration of treatment is 3 days
- Single-dose treatment with a fluoroquinolone (levofloxacin 250 mg, ofloxacin 400 mg, ciprofloxacin 500 mg) is effective, but these drugs are recommended to be spared for the treatment of more serious infections.
- After single-dose treatment, symptoms start to subside in a few days similarly to longer courses 1.
- If the patient's urine flow is abnormal due to functional or structural defects or if the patient has renal failure, longer antimicrobial courses (5–14 days) may be necessary.
|Drug||Daily dose||Treatment duration|
|Trimethoprim||160 mg × 2 or 300 mg × 1||3 days|
|Nitrofurantoin||75 mg × 2||3 days|
|Pivmecillinam||200 mg × 3 or 400 mg × 2||3 days|
- Infection at the renal level should be suspected if the patient presents with fever, flank or back pain, and CRP concentration is > 40 mg/l. Urinary symptoms may be absent.
- A patient with pyelonephritis who is in good general condition can be treated at home with oral fluoroquinolones. Treatment duration is 7 days with fluoroquinolones 2 and 10 days with other antimicrobial agents (table  )
|Drug||Daily dose||Treatment duration|
|Cefuroxime1||750–1 500 mg × 3 i.v.||10 days|
|Sulpha-trimethoprim2||160/800 mg × 2 p.o.||10 days|
UTI in a male patient
- Prostatic hyperplasia predisposes the patient to infections.
- The prostate should be palpated and the amount of residual urine determined  . If indicated, serum PSA and creatinine should also be determined.
- In cystitis, the treatment duration is 7–14 days. Suitable antimicrobials are e.g. trimethoprim or fluoroquinolones (dosage: see tables
- Effective concentrations will not be achieved in the prostate with nitrofurantoin or pivmecillinam.
- In a febrile UTI, a fluoroquinolone is the drug of choice. Treatment duration is 14 days.
- UTI in men is often associated with prostatitis or epididymitis.
- Palpation of the prostate and the scrotal organs is indicated.
- A urologist should be consulted after a febrile infection.
- Acute bacterial prostatitis  is a rare infection with severe symptoms; most cases are sequelae of a recent prostate biopsy. Treatment duration is 2–4 weeks.
- Chronic bacterial prostatitis
should be suspected if the UTI recurs after treatment (same causative agent).
- The recommended treatment duration is 4–6 weeks according to the speed of response.
- If the patient is diagnosed with a recurring symptomatic chronic bacterial prostatitis (recurrent UTIs and calcifications in the prostate), a 2–3-month course of an oral fluoroquinolone is recommended, followed by prophylactic drug therapy.
- If bacterial culture remains negative, the condition in question may be chronic pelvic pain syndrome  .
UTI during pregnancy
- The eradication of infection must be confirmed by urine culture.
- Asymptomatic bacteriuria should be treated and monitored as cystitis due to the increased risk of pyelonephritis and premature delivery [B] .
- The recommended treatment duration in cystitis and asymptomatic bacteriuria is 5 days [C] ; see table 
- Treatment for pyelonephritis during pregnancy is initiated at a hospital.
- Cefuroxime 0.75–1.5 g × 3 i.v.
- Ceftriaxone is effective also when administered intramuscularly and it can be chosen as the initial drug, if dosage once per 24 h or intramuscular administration are of benefit.
- Further treatment with oral first generation cephalosporins, e.g. cephalexin 500 mg × 4 for 10 days
- Nitrofurantoin prophylaxis should be considered in recurrent UTIs during pregnancy.
- , see above.
|Nitrofurantoin 75 mg × 2|
|Pivmecillinam 200 mg × 3||Repeated courses of mecillinam should be avoided during pregnancy, because pivmecillinam lowers the serum carnitine concentration.|
|First generation cephalosporins||Cephalexin 500 mg × 3|
|Amoxicillin 500 mg × 3||Can only be used if the sensitivity of the causative agent has been confirmed|
UTI among residents in long-term care facilities
- Asymptomatic bacteriuria is common among these patients, and urine cultures are taken and empirical treatment started only after other possible diseases and infections that may affect the patient's general condition have been excluded and a decision, based on clinical signs and symptoms, has been made to treat the UTI with antibiotics.
- Due to the variety of causative agents and their changing sensitivity to antimicrobials, a urine specimen for culture should always be obtained when UTI in an institutionalized patient is treated with antimicrobials.
- The antimicrobial drug is chosen individually according to the epidemiological situation in the institution and the patient’s clinical condition; the aim should be to use antimicrobials with the narrowest possible spectrum.
- The same strain: recurrence within 2 weeks after treatment (relapse)
- A new strain, or recurrence more than 2 weeks after treatment (reinfection)
- Prevention of recurrent cystitis without antimicrobials
- There is no research evidence on the benefits of the following preventive measures: excessive drinking (> 2 l per 24 h) of low-calorie drinks, frequent bladder emptying (every 3 hours during the day), management of constipation, avoidance of exposure to cold, use of vitamin C to increase the acidity of the urine, postcoital bladder emptying, avoidance of spermicide use and of wearing a pessary.
- Antimicrobial treatment for the prevention of recurrent cystitis
|Trimethoprim 100 mg in the evening||Methenamine hippurate 1 g × 2|
|Nitrofurantoin 50–75 mg in the evening||Norfloxacin 200 mg × 1 or at 3 nights per week|
- Nitrofurantoin should not be chosen if GFR is < 50 ml/min (calculator ).
- Nitrofurantoin use is associated with the risk of a chronic severe pulmonary reaction.
- Methenamine hippurate is more effective than placebo but less effective than antibiotics in the prevention of UTIs [C]
- Quinolones are only recommended if other prophylactic drugs have proven ineffective or are ill-tolerated.
- In renal failure, beta-lactam antibiotics (e.g. cephalexin 250 mg × 1) can be used for prohpylaxis.
|Trimethoprim 100–300 mg in a single dose||Norfloxacin 200 mg|
|Nitrofurantoin 50–75 mg in a single dose||Ofloxacin 100 mg or ciprofloxacin 100–250 mg|
|Sulpha-trimethoprim (1 single-strength tablet)|
UTI caused by ESBL bacteria
- Gram-negative ESBL bacteria produce extended spectrum beta-lactamases and are thus resistant to penicillins and cephalosporins.
- Cystitis caused by an ESBL positive bacterium may be treated with nitrofurantoin. Clinical cure is also possible with a larger-than-normal dose of pivmesillinam (400 × 3) 3.
- Carbapenem is the recommended drug for empirical treatment of pyelonephritis with severe symptoms in an ESBL positive patient 4.
- Imaging studies or urological investigations of the urinary tract are not necessary in women who have recurrent cystitides or a pyelonephritis.
- Consultation with a urologist is recommended in a febrile UTI of a male patient.
Investigations are warranted if
- an acute pyelonephritis recurs or there is no response to appropriate treatment within a few days
- there are signs of an obstruction to the urine flow or other clearly complicating factors.
- Abdominal pains in conjunction with pyelonephritis or an atypical causative agent (e.g proteus or candida) also indicate further investigations.
- The first-line additional investigation is renal ultrasonography.
- Auquer F, Cordón F, Gorina E, Caballero JC, Adalid C, Batlle J, Urinary Tract Infection Study Group. Single-dose ciprofloxacin versus 3 days of norfloxacin in uncomplicated urinary tract infections in women. Clin Microbiol Infect 2002 Jan;8(1):50-4.
- Sandberg T, Skoog G, Hermansson AB et al. Ciprofloxacin for 7 days versus 14 days in women with acute pyelonephritis: a randomised, open-label and double-blind, placebo-controlled, non-inferiority trial. Lancet 2012;380(9840):484-90.
- Auer S, Wojna A, Hell M. Oral treatment options for ambulatory patients with urinary tract infections caused by extended-spectrum-beta-lactamase-producing Escherichia coli. Antimicrob Agents Chemother 2010;54(9):4006-8.
- Rottier WC, Ammerlaan HS, Bonten MJ. Effects of confounders and intermediates on the association of bacteraemia caused by extended-spectrum ß-lactamase-producing Enterobacteriaceae and patient outcome: a meta-analysis. J Antimicrob Chemother 2012;67(6):1311-20.