Transcript URINARY TRACT INFECTION

In the name of
GOD
1
Dr.Hedayati
2

1. Acute uncomplicated cystitis and pyelonephritis
in women
2. Acute uncomplicated cystitis, pyelonephritis, and
asymptomatic bacteriuria in men
3. Acute complicated cystitis and pyelonephritis
4. Approach to the adult with asymptomatic
bacteriuria
5. Urinary tract infections and asymptomatic
bacteriuria in pregnancy
3
Acute uncomplicated cystitis
and pyelonephritis in women

4

Most episodes of cystitis and pyelonephritis
are generally considered to be
uncomplicated in otherwise healthy
nonpregnant adult women.
A complicated urinary tract infection,
whether localized to the lower or upper tract,
is associated with an underlying condition
that increases the risk of failing therapy.
5

Common
Risk factors :
recent sexual intercourse
recent spermicide use
history of urinary tract infection
6
MICROBIOLOGY

1.
2.
3.
4.
Escherichia coli
75 to 95%
Enterobacteriaceae: Proteus mirabilis
Klebsiella pneumoniae
Staphylococcus saprophyticus
7
Antimicrobial resistance

 Resistance rates >20 % : ampicillin & trimethoprim
use of TMP-SMX in the preceding 3 to 6 months was an
independent risk factor for TMP-SMX resistance in women
with acute uncomplicated cystitis.
 Fluoroquinolone resistance rates were <10 %.
 Resistance rates for first and second generation oral
cephalosporins and amoxicillin-clavulanic acid are :
<10 %.
 Nitrofurantoin : good in vitro activity.
8
CLINICAL
MANIFESTATIONS

Dysuria may also be a manifestation of
vaginitis or urethritis.
9
DIAGNOSIS

 A pelvic examination is indicated if factors
suggesting vaginitis or urethritis are present.
Pregnancy testing is also appropriate.
 Urinalysis in the absence of urine culture is
sufficient for diagnosis of uncomplicated cystitis
if symptoms are consistent with UTI.
 Imaging studies are not routinely required for
diagnosis of acute uncomplicated pyelonephritis.
10
Urinalysis

 Pyuria : almost all women with acute cystitis or
pyelonephritis
Its absence : alternative diagnosis or
in a patient with pyelonephritis, the
presence of an obstructing lesion .
 Pyuria : ≥10 leukocytes/microL .
 White blood cell casts in the urine are diagnostic of
upper tract infection.
11
…Urinalysis

The presence of hematuria is helpful since it
is common in the setting of UTI but not in
urethritis or vaginitis.
Hematuria is not a predictor for complicated
infection and does not warrant extended
therapy.
12
…Urinalysis

 Dipsticks :
1. leukocyte esterase (reflecting pyuria)
2. nitrite (reflecting the presence of Enterobacteriaceae, which
convert urinary nitrate to nitrite)
 Leukocyte esterase : detect >10 leukocytes per HPF(sensitivity of
75 to 96 percent; specificity of 94 to 98 percent)
 The nitrite test is fairly sensitive and specific for detecting ≥10(5)
CFU
negative results should be interpreted with caution
False positive nitrite tests can occur with substances that turn
the urine red, such as phenazopyridine or ingestion of beets.
13
Urine culture

Urine culture and antimicrobial susceptibility
testing of uropathogens should be performed
in all women with acute pyelonephritis.
14
TREATMENT

Cystitis
1. Nitrofurantoin :100 mg orally twice daily for 5 days
early clinical efficacy rate with 5 to 7 day regimen 90
to 95 %
Nitrofurantoin should be avoided :
if there is suspicion for early pyelonephritis,
is contraindicated when GFR<60 mL/minute.
15
TREATMENT

…Cystitis
2.
Cotrimoxazole : 160/800 mg twice daily for 3 days
early clinical efficacy rate with 3 to 7 day regimen 86 to
100 %
Empiric TMP-SMX should be avoided :
if the prevalence of resistance is known to exceed 20 %
if the patient has taken TMP-SMX for cystitis in the
preceding 3 months
***Trimethoprim (100 mg twice daily for three days) is used
in place of TMP-SMX and is considered equivalent
16
TREATMENT

…Cystitis
 Fluoroquinolones (ciprofloxacin, levofloxacin,
ofloxacin in 3-day regimens) are reasonable
alternative agents.
very effective for treatment of acute cystitis.
17
TREATMENT

…Cystitis
 Amoxicillin-clavulanate : for duration of 7 days
 Other beta lactams, such as cephalexin, are less well
studied but may be acceptable in certain settings.
 Ampicillin or amoxicillin should NOT be used for
empiric treatment.
18
TREATMENT

Pyelonephritis:
 Outpatient management is acceptable for patients
with mild to moderate illness who can be
stabilized with rehydration and antibiotics in an
outpatient facility and discharged on oral
antibiotics under close supervision.
 Inpatient management is warranted in the setting
of severe illness with high fever, pain, and marked
debility, inability to maintain oral hydration or
take oral medications, pregnancy, or concerns
about patient compliance.
19
TREATMENT

…Pyelonephritis/Outpatient:
1.
Ciprofloxacin (500 mg orally twice daily
for 7 days or levofloxacin (750 mg orally
once daily for 5 to 7 days)
Fluoroquinolone resistance > 10 %, an
initial intravenous dose of a long acting
parenteral antimicrobial such as ceftriaxone
(1 gram), should be administered.
20
TREATMENT

…Pyelonephritis/Outpatient:
2.
Cotrimoxazole (160/800 mg twice-daily).
 If these agents is used in the absence of susceptibility data, an
initial intravenous dose of a long-acting parenteral
antimicrobial should be administered
 Ciprofloxacin or levofloxacin can be used in 5 to 7 day regimens
in most patients with mild to moderate disease who have a
rapid response to treatment. The duration of treatment with
cotrimoxazole is 14 days, but clinical experience suggests that 7
to 10 days is effective in women who have a rapid response to
treatment.
3. Oral beta lactam agents are less effective than other agents for
treatment of pyelonephritis .If the pathogen is susceptible and
an oral beta lactam agent is continued, it should be
administered for at least 14 days.
21
TREATMENT

 …Pyelonephritis/Inpatient:
 initially with an intravenous antimicrobial regimen
suc:
fluoroquinolone
aminoglycoside
extended-spectrum cephalosporin,
extended-spectrum penicillin,
carbapenem.
22
Follow-up

 Follow-up urine cultures are not needed in patients
with acute cystitis or pyelonephritis whose
symptoms resolve on antibiotics
23
Symptomatic therapy

 Clinical manifestations should respond to
antimicrobial therapy within 48 hours.
 In the interim, for some patients a urinary analgesic
such as oral phenazopyridine (200 mg three times
daily) may be useful to relieve discomfort due to
severe dysuria. A two day course is usually sufficient
to allow time for symptomatic response to
antimicrobial therapy and minimize inflammation.
 This agent should not be used chronically since it
may mask clinical symptoms requiring clinical
evaluation
24
Acute uncomplicated cystitis,
pyelonephritis, and
asymptomatic bacteriuria in men

25

 It has been conventional to consider all UTIs (and
presumably asymptomatic bacteriuria) in men as
complicated, since the majority occur in infants or
the elderly in association with urologic
abnormalities, such as bladder outlet obstruction
(eg, due to prostatic hyperplasia) or instrumentation.
 Acute uncomplicated UTIs occur in a small number
of men between 15 and 50 years of age.
26
ASYMPTOMATIC BACTERIURIA

 Positive urine culture in the absence of symptoms.
 Asymptomatic bacteriuria in young healthy men is
rare .
 Among the elderly, the prevalence of asymptomatic
bacteriuria is lower in men than in women.
27
…ASYMPTOMATIC BACTERIURIA

 Screening for asymptomatic bacteriuria is warranted
prior to transurethral resection of the prostate or
other urologic procedures for which mucosal
bleeding is anticipated .
 It is appropriate to perform urinalysis prior to hip
arthroplasty if a urinary catheter is expected to be in
place postoperatively. An abnormal urinalysis
should prompt urine culture, and the presence of
urinary tract infection (eg, ≥10(4) CFU/mL) warrants
treatment with three days of antibiotic therapy prior
to surgery.
28
ACUTE CYSTITIS AND
PYELONEPHRITIS
Diagnosis

 A urine culture should be performed in all men with
symptoms suggestive of cystitis.
 An evaluation for causative factors should be pursued .If
an underlying risk factor is not obvious, further
evaluation should be considered.
 Men with recurrent cystitis should undergo evaluation
for prostatitis.
 Urologic evaluation is probably not necessary in young
healthy men with no obvious complicating factors who
have a single episode of cystitis that responds promptly to
antimicrobial treatment.
 Imaging studies are not routinely required for diagnosis
of acute uncomplicated pyelonephritis.
29
ACUTE CYSTITIS AND
PYELONEPHRITIS
Diagnosis

 The presence of hematuria is helpful since it
is common in the setting of UTI but not in
urethritis.
Hematuria is not a predictor for complicated
infection and does not warrant extended
therapy.
30
Urine culture

A midstream urine culture is recommended
to confirm the diagnosis of urinary tract
infection in men, using colony count criteria
of ≥10(4) CFU/mL .
The spectrum of isolates causing
uncomplicated cystitis in men is similar to
that in women.
31
Differential diagnosis

Chronic prostatitis should be considered in
men with cystitis, particularly in those men
who have recurrent UTIs.
Urethritis must be considered in sexually
active men.
32
Treatment
Cystitis

Treatment duration of 7 to 14 days given
the possibility of associated prostatitis,
which may be difficult to discern clinically.
Nitrofurantoin and beta-lactams should
usually not be used in men with cystitis,
since they do not achieve reliable tissue
concentrations and would be less effective
for occult prostatitis.
33
Follow up

Persistent symptoms after 48 to 72 hours of
appropriate antimicrobial therapy or
recurrent symptoms within a few weeks of
treatment should have evaluation for
complicated infection .
34
Acute complicated cystitis and
pyelonephritis

35
Diabetes
Pregnancy
History of acute pyelonephritis in the past year
Symptoms for seven or more days before seeking
care
Antimicrobial resistant uropathogen
Hospital acquired infection
Renal failure
Urinary tract obstruction
Presence of an indwelling urethral catheter, stent,
nephrostomy tube or urinary diversion
Recent urinary tract instrumentation
Functional or anatomic abnormality of the urinary
tract
History of urinary tract infection in childhood
Renal transplantation
Immunosuppression
36

Acute complicated pyelonephritis is
progression of upper urinary tract infection
to emphysematous pyelonephritis, renal
corticomedullary abscess, perinephric
abscess, or papillary necrosis.
37
MICROBIOLOGY

 The microbial spectrum of complicated UTI is
broader and includes the above organisms as well as
Pseudomonas, Serratia, and Providencia species, in
addition to enterococci, staphylococci, and fungi .
 In addition, organisms causing complicated cystitis
are more likely to be resistant to commonly used
oral antimicrobials recommended for uncomplicated
cystitis
38

 Chronic pyelonephritis is an uncommon cause of
chronic tubulointerstitial disease due to recurrent
infection, such as infection in association with a
chronically obstructing kidney stone or
vesicoureteral reflux.
 Affected patients can present with weeks to months
of insidious symptoms.
39
Radiographic imaging

 Persistent clinical symptoms after 48 to 72 hours of
appropriate antibiotic therapy for acute
uncomplicated urinary tract infection
 pyelonephritis who also have symptoms of renal
colic or history of renal stones, diabetes, infection
with a particularly virulent organism, history of
prior urologic surgery, immunosuppression,
repeated episodes of pyelonephritis, or urosepsis .
40
…Radiographic imaging

 CT : study of choice to detect complicated urinary tract
infection
 CT : more sensitive than IVPor renal ultrasound
 CT without contrast has become the standard
radiographic study for demonstrating calculi, gasforming infections, hemorrhage, obstruction, and
abscesses.
 Contrast is needed to demonstrate alterations in renal
perfusion.
41
…Radiographic imaging

 CT findings may include localized hypodense lesions
due to ischemia induced by marked neutrophilic
infiltration and edema
 Resolution of radiographic hypodensities may lag
behind clinical improvement by up to three months .
42
…Radiographic imaging

 Renal ultrasound is appropriate in patients for
whom exposure to contrast or radiation is
undesirable .
 MRI is not advantageous over CT except when
avoidance of contrast dye or ionizing radiation is
warranted .
43
TREATMENT

Cystitis
 Oral fluoroquinolone such as ciprofloxacin
(500 mg orally twice daily) or levofloxacin
(750 mg orally once daily) for 5 to 14 days.
Short regimens are appropriate in patients
with mild to moderate symptoms and rapid
clinical response.
Fluoroquinolones are comparable or superior
to other broad spectrum antibiotics,
including parenteral regimens
44
…TREATMENT

…Cystitis
 Nitrofurantoin, cotrimoxazole and oral beta-lactams
are poor choices for empiric oral therapy in
complicated cystitis.
45
…TREATMENT

…Cystitis
 Parenteral therapy :patients who cannot tolerate oral therapy
patients with infection due to resistant
organisms.
 levofloxacin ,ceftriaxone ,an aminoglycoside ,an extendedspectrum beta-lactam, or a carbapenem.
 The presence of gram-positive cocci is suggestive of
enterococci and requires treatment with ampicillin or
amoxicillin .
 After clinical improvement is observed, parenteral therapy
can be switched to oral therapy.
 The duration of treatment for acute complicated cystitis is 5
to 14 days.
46
…TREATMENT

Pyelonephritis
 Initially as inpatients.
 Broad-spectrum parenteral antibiotics
 Underlying urinary tract anatomic or functional abnormalities
Antibiotics alone may not be successful unless such underlying
conditions are corrected.
 Antibiotics should be administered for at least 10 to 14 days;
 Treatment may be completed with oral therapy
 Acceptable agents include levofloxacin, ciprofloxacin, or
trimethoprim-sulfamethoxazole
47
Follow-up

 not needed in patients with acute cystitis or
pyelonephritis whose symptoms resolve on
antibiotics.
 Patients with persistent or recurrent symptoms
within a few weeks of treatment for acute
complicated urinary tract infection should have a
reevaluation
48
Approach to the adult with
asymptomatic bacteriuria

49
CLINICAL DEFINITIONS

 The presence of pyuria (≥10 leukocytes/mm3 of
uncentrifuged urine) is not sufficient for diagnosis
of bacteriuria
50
Women

 Two consecutive clean-catch voided urine specimens
with isolation of the same organism in quantitative
counts of ≥10(4) cfu/mL.
 A single positive urine specimen with ≥10(5) cfu/m.
51
Men

 single clean-catch voided urine specimen with
isolation of a single organism in quantitative counts
of ≥10(5) cfu/mL .
 In general, external contamination during voiding
among men is an extremely unlikely cause of
significant bacteriuria.
52
Catheterized specimens

 single catheterized specimen with isolation of a
single organism in quantitative counts of ≥10(2)
cfu/mL.
 There have been no comparisons of culture yields
from urethral catheterized specimens and
suprapubic aspiration specimens
53
EPIDEMIOLOGY

 Women :Pregnant and non-pregnant women have a
similar prevalence.
 Diabetic women :correlated with duration and
presence of long term complications of diabetes,
rather than with metabolic parameters of diabetes
control .
 Men :Diabetic men do not appear to have a higher
prevalence of bacteriuria than nondiabetic men
54
WHOM TO TREAT

1. pregnant women
2. patients undergoing urologic procedures in
which mucosal bleeding is anticipated
55
WHOM NOT TO TREAT

Diabetic patients
Patients with spinal cord injury
 Indwelling urethral catheters.
56

Avoiding treatment of asymptomatic
bacteriuria is important for reducing
development of antibiotic resistance, and a
hospital and ambulatory performance
measure for not treating asymptomatic
bacteriuria in adults has been proposed
57
Urinary tract infections and
asymptomatic bacteriuria in
pregnancy

58
Diagnosis

 Isolation of Lactobacillus warrants treatment if it is
the only organism isolated in consecutive urine
cultures with high colony counts, although the
significance in pregnancy is not known.
59
…Diagnosis

 Screening for asymptomatic bacteriuria should be
performed at 12 to 16 weeks gestation
 Rescreening is generally not performed in low risk
women, but can be considered in women at high risk
for infection (eg, presence of urinary tract anomalies,
hemoglobin S, or preterm labor)
60
Treatment

 Penicillins and cephalosporins are safe in pregnancy.
 ceftriaxone, may be inappropriate the day before parturition
because of the possibility of bilirubin displacement and subsequent
kernicterus.
 Nitrofurantoin and sulfonamides : birth defects .The safest course is
to avoid using nitrofurantoin in the first trimester.
 Nitrofurantoin : hemolytic anemia in the mother and fetus with G6PD deficiency
 Sulfonamides should be avoided in the last days before delivery
because they can increase the level of unbound bilirubin in the
neonate.
 Trimethoprim is generally avoided in the first trimester because it
is a folic acid antagonist .
 Fluoroquinolones and tetracyclines are contraindicated during
pregnancy.
61

 Nitrofurantoin (100 mg orally every 12 hours for five
to seven days)
 Amoxicillin (500 mg orally every 12 hours for three
to seven days)
 Amoxicillin-clavulanate (500 mg orally every 12
hours for three to seven days)
 Cephalexin (500 mg orally every 12 hours for three to
seven days)
62
Follow-up

 a week after completion of therapy
 repeated monthly until the completion of the
pregnancy.

63
Follow-up

 If the follow-up culture is positive [≥10(5) cfu/mL]
with the same species of bacteria (persistent
bacteriuria), another course of antimicrobial based
on susceptibility data should be administered - either
the same antimicrobial in a longer course (eg, seven
days, if a three-day regimen was used previously) or
a different antimicrobial in a standard regimen.
64
Follow-up

 If the follow-up culture is positive with a different
species or if the follow-up culture is not positive
[<10(5) cfu/mL], but then a subsequent follow-up
culture is positive (with the same or different
species), both scenarios imply recurrent bacteriuria
and treatment should be administered with one of
the recommended regimens based on antimicrobial
susceptibility testing. True persistent bacteriuria
implies initial therapy was inadequate and thus
requires modification different therapeutic approach
than in women who develop recurrent bacteriuria.
65
Suppressive therapy

 persists after two or more courses of therapy.
Nitrofurantoin (50 to 100 mg orally at bedtime) for the
duration of the pregnancy may be used if the organism is
susceptible.
 Monthly cultures are not necessary if suppressive therapy
is administered; however, breakthrough bacteriuria can
occur during suppressive therapy, so at least one later
culture, such as at the start of the third trimester, should
be performed to ensure suppression is working.
 If a follow-up culture is positive [≥10(5) cfu/mL], another
course of antimicrobial based on susceptibility data
should be administered. The suppressive regimen should
be reassessed and adjusted if needed.
66
ACUTE CYSTITIS

 It is reasonable to use a quantitative count ≥10(3)
cfu/mL in a symptomatic pregnant woman as an
indicator of symptomatic UTI.
67
Treatment

 Nitrofurantoin (100 mg orally every 12 hours for five
to seven days)
 Cefpodoxime (100 mg twice daily for three to seven
days)
 Amoxicillin-clavulanate (500 mg orally every 12
hours for three to seven days)
 TMP-SMX (one double strength twice daily for three
days) in the second trimester
 Amoxicillin (for treatment of enterococcus; 500 mg
twice daily every 12 hours seven days).
68
Follow-up

 As asymptomatic bacteriuria
69
Suppressive therapy

 As asymptomatic bacteriuria
70
Recurrent infection

 antimicrobial prophylaxis for the duration of pregnancy.
 It is reasonable to use postcoital prophylaxis if the UTI is
thought to be sexually related, which is common.
 If the woman has other conditions that potentially
increase the risk of urinary complications during episodes
of UTI (eg, diabetes or sickle cell trait), prophylaxis
should be considered after the first UTI during pregnancy
 .The choice of antimicrobial should be based on the
susceptibility profile of the cystitis strains. Ideally, daily
or postcoital prophylaxis with low dose nitrofurantoin (50
to 100 mg PO postcoitally or at bedtime) or cephalexin
(250 to 500 mg PO postcoitally or at bedtime) can be used.
71
Prior recurrent UTI

 As a result, we recommend postcoital prophylaxis in
pregnant women who have recurrent UTIs that
appear to be temporally related to sexual intercourse.
The preferred regimen is a single postcoital dose of
either cephalexin (250 mg) or nitrofurantoin (50 mg).
72
ACUTE
PYELONEPHRITIS

 Parenteral beta-lactams are the preferred antibiotics.
 Carbapenems are usually effective in the treatment of
serious extended-spectrum beta lactamase (ESBL)producing strains causing infections
 pregnant women should have definite improvement
within 24 to 48 hours. Once afebrile for 48 hours, patients
can be switched to oral therapy and discharged to
complete 10 to 14 days of treatment .
 If symptoms and fever persist beyond the first 24 to 48
hours of treatment, a repeat urine culture and urinary
tract imaging studies should be performed to rule out
persistent infection and urinary tract pathology.
73
Preventing recurrence

 low dose antimicrobial prophylaxis with an agent to
which the organism is susceptible is warranted for
the remainder of the pregnancy; reasonable options
include nitrofurantoin (50 to 100 mg orally at
bedtime) or cephalexin (250 to 500 mg orally at
bedtime) .
74
Failure of outpatient
therapy

 Outpatient therapy of pregnant women with
pyelonephritis does not recommend initiating
therapy of pyelonephritis to pregnant women in the
outpatient setting.
75
Thank you
76