Title: Urinary tract infections - AMBOSS
Headings: 
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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: indicates presence of bacteria that convert
nitrates
to
nitrites
, which are most commonly gram-negative bacteria (e.g.,
E.coli
)
Positive
urease
: indicates presence of
urease-producing organisms
(e.g.,
Proteus
,
Klebsiella
,
S. saprophyticus
), which cause the urine to become more alkaline (pH > 7)
Other findings
Leukocyte
casts will likely be absent with lower UTIs. Hematuria
and mild
proteinuria
Urine culture
Diagnostic criteria for UTI
Significant bacteriuria: defined as ≥ 105
CFU
/mL; confirms the diagnosis
The presence of any organisms in a urine specimen obtained by suprapubic
aspiration
of the bladder confirms the diagnosis. 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
: