Transcript Urinary Tract Infections

Urinary Tract Infections
Meral Sönmezoğlu
Division of Infectious Diseases
Yeditepe University Hospital
Learning objectives UTI’s
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Epidemiology
Pathogenesis
Risk Factors
Types of cystitis
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Evaluation
Therapy
Epidemiology UTI’s
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UTIs are the second most common cause for prescription
of antibiotics
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Most infections are limited to the lower urinary tract
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30 times more likely
in young women than
young men
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Incidence in men rises
dramatically after age 50
Relative frequency of nosocomial
(hospital-acquired) infections
Site
% of total
Urinary tract
34
Surgical site
17
Bloodstream
14
Pneumonia
13
Other
21
Pathogenesis UTI’s
Bacteria travel:
 Ascending route via the
urethra 95%
 Hematogenous (kidney->
bladder)
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Endocarditis
Tuberculosis
Direct (connection bowelbladder)
Bacterial factors
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Inoculum size
Virulence
Adherence
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E. coli adhere to
urothelial cells
Proteus, Providencia
adhere to lumen of
catheter material
Virulence
Host factors
Infection
No infection
Host defense mechanisms
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Mechanical
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Interference
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Normal bacteria flora (meatus)
Chemical
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Dilution and flow of urine
Length of urethra
Osmolality and pH of urine
Prostatic fluid
Anti-adherence mechanisms in bladder
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Urinary immunoglobulins
Mucosal antibacterial activity
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Risk factors UTI’s (I)
Alteration/introduction of bacteria
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Antibiotics
Spermicides
Vaginal atrophy (age)
Sex
Insertive rectal sex
Inserting toys
Patient education:
Void after intercourse,
Proper wiping, front to back
once
Risk factors UTI’s (II)
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Urinary stasis
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Neurologic bladder
Reflux into the ureters (pregnancy)
Obstruction
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Diabetes mellitus
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Congenital anatomical abnormalities
Prostate hypertrophy (age)
Stones, tumor
Glycosuria
Foreign materials
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Stones
Stents
Catheters
Pathogenesis of cystitis
Types of urinary tract problems
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Asymptomatic bacteriuria
Dysuria
Cystitis
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Complicated UTI
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Acute uncomplicated cystitis
Recurrent cystitis
Pyelonephritis
UTI’s in men, pregnant women, children
Prostatitis
Other
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Catheter associated UTI
Candida in urine
Sterile pyuria
Definitions (I)
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Asymptomatic bacteriuria:
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isolation of a specified quantitative count of
bacteria
in an appropriately collected urine specimen
obtained from a person without symptoms or
signs referable to urinary infection
Acute uncomplicated UTI (cystitis):
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symptomatic bladder infection
characterized by frequency, urgency, dysuria or
suprapubic pain
in a woman with a normal genitourinary tract
Definitions (II)
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Acute nonobstructive pyelonephritis:
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renal infection
characterized by costovertebral angle pain
often with fever
sometimes with bacteraemia
Complicated urinary tract infection:
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may involve the bladder or kidneys
symptomatic urinary infection
in individuals with functional or structural
abnormalities of the urinary tract
What can the laboratory do with a
sample of urine?
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Urinalysis
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Microscopy
Dipstick
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Quantitative culture
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Specialized cultures (TB, fungi)
Urine dipstick
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Leukocyte esterase: rapid
screening test for detecting
pyuria
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Patients with symptoms and
negative LE should have a
urine microscopic
examination for pyuria
Urinary nitrite
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Nitrite is formed when
bacteria reduce the nitrate
that is normally found in the
urine
False negatives common, but
false positives are rare
Urinary tract organism
quantification
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Bladder urine is sterile
Distal urethra is not sterile
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How can we differentiate:
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bladder bacteria (pathogens) from
urethral bacteria (contaminants)?
What is a positive culture?
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Classic definition:
> 105 cfu/ml
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With symptoms:
> 103 cfu/ml
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90% chance of
actual infection
Microscopy
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A true UTI is accompanied by
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Pyuria
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Lack of epithelial cells
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>5/ mm³ indicates contamination
Only one bacterial species (monoculture)
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>10 leukocytes/mm³ of uncentrifuged urine
unless catheter in place
>105 cfu
Do not culture urine unless
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Indicated AND
Abnormal UA
Dysuria
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Dysuria can be caused by
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Vaginitis -no pyuria and <102 cfu/ml)
Candida
 Trichomonas
 atrophy of vaginal tissues
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Urethritis –pyuria and <102 cfu/ml, gradual
Chlamydia
 Neisseria gonorrhoeae
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Cystitis – pyuria and >103 cfu/ml, onset abrupt
Asymptomatic bacteriuria why screen?
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Screening of asymptomatic people for
bacteriuria is only appropriate to prevent
adverse events
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In pregnancy (Gp B strep)
Prior to urologic surgery
Undesirable outcomes associated with therapy:
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Antimicrobial resistance
Adverse drug effects
Costs
C. difficile associated disease
Asymptomatic bacteriuriaHealthy, premenopausal women
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Bacteriuria increases risk for symptomatic UTI
Not associated adverse outcomes
Treatment of asymptomatic bacteriuria
neither decreases frequency of symptomatic
infection
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bacteriuria
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Screening for and treatment of asymptomatic
bacteriuria is not indicated
Asymptomatic bacteriuria - Pregnant
women
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20-30 fold increased risk of pyelonephritis
during pregnancy
More likely to experience premature delivery
and to have low birthweight infants
Treatment of bacteriuria decreases above
risks
Screen for bacteriuria by urine culture at
least once in early pregnancy and treat for
3-7 days if positive
Asymptomatic bacteriuria Elderly institutionalized subjects
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No decrease in rate of
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symptomatic infection
improvement in survival
chronic GU symptoms with Abx therapy
Screening and treatment of asymptomatic
bacteriuria in elderly institutionalized
residents of long-term care facilities not
recommended
Asymptomatic bacteriuria –
Patients with indwelling catheters
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Antimicrobial therapy not associated with
decrease in rate of symptomatic infection
High incidence of recurrence, usually with
more resistant organisms
Asymptomatic bacteriuria or funguria
should not be screened for or treated in
patients with indwelling urethral catheter
Acute uncomplicated UTI
(cystitis)
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Symptoms
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Dysuria, frequency,
urgency
Initial and terminal
hematuria
Suprapubic discomfort
Low-grade fever may
occur
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Diagnosis
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Dipstick or microscopy
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Culture
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Exclude other causes
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STD
Vaginitis
Nitrite positive
Positive LE/WBC
(>10 WBC’s)
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Not routinely necessary
Carefully obtained
clean catch
104-5 cfu/ml
1 bacterial species only
Acute uncomplicated UTI
(cystitis)
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Bacteria
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E. coli in 80-90%
Staph. saprophyticus in 5-15%
Proteus and Klebsiella species
Adult female
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No anatomic/functional/immunologic
abnormalities
Non-pregnant
Acute uncomplicated UTI Therapy
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Resistance varies
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30% resistant to amoxicillin
1-20% to nitrofurantoin
5-15% to TMP-SMX
Recommend: course of
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TMP-SMX as first choice (3 days)
Fluoroquinolone as second (3 days)
Nitrofurantoin (7 days)
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Does not penetrate in kidney
IDSA guideline
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TMP-SMX (160/800 mg tablet twice daily for 3
days)
Nitrofurantoin monohydrate/macrocrystals (100
mg twice daily for 5 days);
Fosfomycin trometamol (3 g powder single dose
Pivmecillinam (400 mg bid for 3–7 days
Fluoroquinolones are highly effective in 3-day
regimens
Other treatment – non antimicrobial
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Acidification
Acid urine is antibacterial
 Cranberry juice has precursors to hippuric
acid and so acidifies urine
BUT
 Have to avoid diet that alkalizes urine – milk,
fruit juice
 Acid can precipitate stones in the urine (oxalic
acid stones from ascorbic acid intake)
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Recurrent Cystitis
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Relapse: same organism in <2 weeks
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Suggests uneradicated focus
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Abx resistance
Non compliance
Reinfection - may be same or different
organism: Interval >2 weeks
Hygiene/wiping
 Post-coital
 Vaginal atrophy
 Post-void residual (prolapse)
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Complicated UTI
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Child, male, pregnant female
Kidney involvement, 2nd bacteraemia
Abnormality
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Anatomy, function, immunology
Urologic procedure
Catheterization
Unusual or resistant organisms
Acute pyelonephritis
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Usually E. coli
Obtain urine culture
 If hospitalized obtain blood cultures
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Mostly an ascending infection
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Disease severity
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Mild
Life threatening urosepsis
Acute pyelonephritis -Therapy
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Mild to moderately ill patients
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Severely ill patients
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TMP-SMX (bactrim) amox/clav, cefuroxime or fluoroquinolone
Patients usually improve in 48-72 hours
Treat for 1-2 weeks
Ampicillin + aminoglycoside
IV therapy until patient afebrile for 48-72 hours
Treat for 2 weeks
If fever persists and all children and men:
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Renal US, CT or MR ± IVP
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Look for perinephric abscess
Exclude urinary obstruction
Management: UTI in Pregnancy
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Nitrofurantoin 50-100mg QID X 7- 10 days
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Amok/klav 250mg QID X 7- 10 days
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Sefaleksin 250 mg BID-QID X 7- 10 days
Complicated UTI:
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> 2 UTI’s / year
Antibiotic resistance
Any UTI in a male.
Cystitis in males
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Young men (rare in men under 50)
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Older men
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Calculi
Enlarged prostate (obstruction)
Chronic prostatitis
Organisms differ
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Anatomic abnormalities
Anal insertive sex, toys
E. coli accounts for 40-50%
Proteus and Providencia species accounting for next most
frequent cause
Most common cause of relapsing UTI is chronic bacterial
prostatitis
UTI’s in males
(other than pyelonephritis)
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Urethritis (STI’s)
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Gonorrhea
Chlamydia
Ureoplasma
Prostatitis
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Same organisms as above
For older males (in addition to above):
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Gram negative rods
Enterococci
Acute prostatitis
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Fever, chills
Dysuria, pain
Marked local tenderness
Excellent penetration by most antibiotic
classes-easily cured
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Complications
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Prostatic abscess
Chronic prostatitis
Chronic prostatitis
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Chronic pain
Dysuria
Recurrent “UTI’s” – same organism
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Poor antibiotic penetration-difficult to treat
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Biofilm
Calculi
Preferred agents
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Fluoroquinolones
TMP-SMX
Role of the catheter in UTI
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Conduit
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Internal lumen
Migration of bacteria along
external surface
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Foreign body
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Biofilm formation
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Protects from host defense
Protects from antibiotics
Incomplete emptying
Situations When a Urinary Catheter is
Used
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A urinary catheter is used in many different
situations:
 A urinary catheter may be inserted to drain
the bladder before or during a surgical
procedure, during recovery from a serious
illness or injury, or to collect urine for testing
 A urinary catheter may be used for a person
who is incontinent of urine, if the person has
wounds or pressure ulcers that would be
made worse by contact with urine
 A urinary catheter is necessary when a
person is unable to urinate because of an
obstruction in the urethra
Types of catheters
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A condom catheter, consists of a soft plastic or rubber sheath,
tubing, and a collection bag for the urine. The sheath is placed
over the penis and the collection bag is attached to the leg.
Collects urine when there is no need for catheter insertion.
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A straight catheter, is used when the catheter is to be inserted
and removed immediately.
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An indwelling catheter, also known as Foley catheter, is left
inside the bladder to provide continuous urine drainage.
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A suprapubic catheter is a type of indwelling catheter. The
suprapubic catheter is inserted into the bladder through a surgical
incision made in the abdominal wall, right above the pubic bone.
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A 3-way catheter for continuous bladder irrigation (CBI) is a
type of indwelling catheter. It is inserted to irrigate the bladder to
prevent obstruction (i.e bleeding)
Catheters
Straight
Condom
Suprapubic
Indwelling
Genitourinary tuberculosis
From:
Johnson and Feehally,
Comprehensive Clinical
Nephrology, 2000, Elsevier
Genitourinary tuberculosis
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Hematogenous seeding can occur in
cortex and forms granuloma
Seeding in the medulla
In both sites
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Granulomas form
Caseation
Erosion into collecting system
Further spread to ureters, bladder,
prostate…
Genitourinary tuberculosis
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Requires high index of suspicion
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Clinical disease insidious
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Key finding is sterile pyuria
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Dysuria, renal functional defects
PPD skin testing
Culture M. tuberculosis from urine
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Early AM sample (urine concentrated)
Multiple urine samples
Imaging
Community-Acquired UTI
E.coli
S.epi &
gm - enterics
Enterococcus
Proteus
K.pneumoniae S.saprophyticus
National data
Turkish study
TUS 2010
Aşağıdakilerden hangisi idrar yolu
enfeksiyonlarının gelişiminde risk
faktörü değildir?
A) İşeme disfonksiyonu
B) Kabızlık
C) Nörojenik mesane
D) Hamilelik
E) Hipertansiyon
TUS 2010
Aşağıdakilerden hangisi idrar yolu
enfeksiyonlarının gelişiminde risk
faktörü değildir?
A) İşeme disfonksiyonu
B) Kabızlık
C) Nörojenik mesane
D) Hamilelik
E) Hipertansiyon
TUS 2010

İdrar yolu enfeksiyonlarında piyüri tanısı
koyabilmek için orta akım idrarında
mm3’de en az kaç lökosit olmalıdır?

A) 10
B) 100
C) 1000
D) 10.000
E) 100.000
TUS 2010

İdrar yolu enfeksiyonlarında piyüri tanısı
koyabilmek için orta akım idrarında
mm3’de en az kaç lökosit olmalıdır?

A) 10
B) 100
C) 1000
D) 10.000
E) 100.000
TUS 2013
Böbrek tubullerinde latent kalan DNA virusu
a) BK virüsü
b) Poxvirüs
c) Herpes virüs
d) Poliovirüs
TUS 2013
Böbrek tubullerinde latent kalan DNA virusu
a) BK virüsü
b) Poxvirüs
c) Herpes virüs
d) Poliovirüs
TUS 2015
TUS 2015