Title: Urinary tract infections - AMBOSS
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Urinary tract infections
Summary
Etiology
Pathogens
Bacteria
Viruses
Other pathogens
Predisposing factors
Host-dependent factors
Other factors
Classification
According to anatomic location
[7]
[8]
According to predisposing factors
[9]
[10]
[11]
According to source of infection
Clinical features
Diagnostics
Approach
Laboratory tests
[14]
[17]
Urinalysis
Urine culture
Diagnostic imaging
Differential diagnoses
Interstitial cystitis (
painful bladder syndrome
)
[19]
[20]
Asymptomatic bacteriuria
[26]
[27]
Other differential diagnoses
Treatment
Antibiotic therapy for uncomplicated UTIs
Principles of therapy
[14]
[30]
Treatment of acute uncomplicated lower UTIs
Treatment of uncomplicated upper UTIs
Antibiotic therapy for complicated UTIs
Antibiotic therapy for recurrent infections
[26]
[27]
Complications
Prevention
Special patient groups
UTI during pregnancy
UTI in children and adolescents
[40]
[41]
References

Content: Indications
Complicated UTI
Age ≥ 65 years
Diaphragm use
Recent use of antibiotics
Suspected lower UTI with the following characteristics
Duration of symptoms > 7 days
Recurrent lower UTI history
A nondiagnostic
urinalysis
Suspicion of
pyelonephritis
or
urosepsis
Typical colony findings
E. coli
: intensely pink on
MacConkey agar
Klebsiella pneumoniae
: viscous colonies
Serratia marcescens
: often red appearance
Proteus mirabilis
: swarming motility pattern
Pseudomonas aeruginosa
: blue-green pigment
Other pathogens
Enterobacter
spp. Enterococcus
Ureaplasma urealyticum
S. saprophyticus
Diagnostic imaging
Indications
Persistent symptoms (after > 48–72 hours of appropriate antibiotic therapy)
Recurrent symptoms (within a few weeks of appropriate treatment)
Suspected
urinary tract obstruction
Severe illness (e.g.,
septic shock
)
CT scan without contrast
[11]
First choice for initial imaging
Indicated in cases of
recurrent UTIs
,
complicated UTIs
, and in patients who do not respond to treatment
Assessment of potential conditions of the urinary tract (e.g.,
urinary stones
, obstruction, tumors, cysts, trauma)
Ultrasound
Assessment of potential
urinary obstruction
Can help diagnose
pyelonephritis
(see “
Pyelonephritis
”)
Indications
UTIs in children < 24 months (to rule out anatomical abnormalities of the urinary tract)
Contraindi