Download Urinary Tract Infections

Urinary Tract Infections
PWM OLLY INDRAJANI
2013
Prevalence of UTIs
• Urinary Tract Infection (UTI) is the most common
bacterial infection affecting humans
• UTI is a serious health problem affecting millions of
people each year
• Over 8 million Americans seek medical attention for
urinary tract infections annually.
• Women are especially susceptible:
one in five women will have at least one urinary
tract infection during her life.
Pathophysiology
• The urinary system
consists of the kidneys,
ureters, bladder, and
urethra.
• The kidneys remove liquid
waste from the blood in
the form of urine
• Keep a stable balance of
salts & substances in the
blood, and produce a
hormone that aids the
formation of RBCs.
Pathophysiology: continued
• The ureters carry urine from the kidneys to the
bladder located in the lower abdomen.
• Urine is stored in the bladder and emptied through
the urethra.
• The ureters and bladder normally prevent urine
from backing up toward the kidneys, and the flow
of urine from the bladder helps wash bacteria out
of the body
• Normal urine is sterile.
• It contains fluids, salts, and waste products.
• It is free of bacteria, viruses, and fungi.
Pathophysiology: Routes of Infection
• Three well recognized routes of infection:
• Ascending Transurethral Infection: fecal
microorganisms colonizing the periurethral area
and enter the bladder via the urethra
• Hematogenous: spread as in staphylococcal
bacteremia or renal cortex resulting in abscess
formation
• Direct Extension: enterovesical fistula
Pathophysiology:
Ascending Transurethral Infection
• Is most common route
• Short female urethra allows bacteria quick access to
the bladder.
• Sexual intercourse forces bacteria into bladder
• Presence of foreskin, fecal incontinence, and poor
toilet habits promote colonization by the fecal
bacteria and contribute to the higher prevalence of
infection seen in uncircumcised infants, young
sexually active men and elderly men with poor anal
sphincter control
Pathophysiology:
Hematogenous Spread
• Hematogenous
spread of bacteria,
fungi, and
mycobacteria from
distant focus of
infection may invade
the kidney, bladder
or prostate
Pathophysiology:
Direct Extension
• Direct extension of bacteria from the gut into
the bladder may occur via a COLOVESICAL,
RECTOVESICAL fistula secondary to
diverticulitis or colon cancer, Crohn’s disease
Classification of Urinary Tract Infections
• Lower UTI: cystitis, urethritis, prostatitis
• Upper UTI: acute or chronic pyelonephritis,
renal or perirenal abscess
• Uncomplicated and Complicated lower or
upper UTI
Classification of Urinary Tract Infections
Complicated Lower or Upper UTI:
– Risk of renal damage,
urosepsis,
abscess formation
Due to
• Presence of functional or anatomic abnormalities,
obstruction, calculi/catheter/stent, pregnancy,
hospitalization, immunosuppression, diabetes
mellitus, sickle cell disease, analgesic/NSAID abuse
Classification of Urinary Tract Infections
• Acute urethral syndrome:
dysuria/frequency with less than 105
colonies/ml of urine
• Asymptomatic bacteriuria: asymptomatic
with more than 105 colonies of the same
bacteria per ml of clean-catch mid-stream
urine
Presenting Signs & Symptoms
Uncomplicated lower UTI
Acute Bacterial Cystitis:
• Dysuria
• Frequency
• Urgency
• Nocturia
• Voiding of small urine volumes
• Incontinence
• Suprapubic or pelvic pain
Associated Signs & Symptoms
•
•
•
•
•
Hematuria
Foul smelling cloudy urine
Men experience a fullness in the rectum
Fever
Flank tenderness
Acute pyelonephritis
• Signs & Symptoms:
– Flank or low back pain, chills, fever,
sweats, nausea, vomiting, headache and
malaise
• Associated Signs & Symptoms:
– May have symptoms of cystitis
– Hematuria, dysuria, polyuria
Signs & Symptoms in the Elderly
•
•
•
•
Less obvious signs:
Loss of appetite or a change in eating habits.
The sudden onset of confusion
Urinary incontinence
Complicated UTI: S/S
• Clinical manifestations can range from
asymptomatic bacteriuria to a severe gram-negative
sepsis with shock
• Can also present with signs and symptoms of acute
cystitis or acute pyelonephritis
• Hospitalized patients who suddenly develop signs
and symptoms of septic shock or urosepsis should
be considered even in the absence of urinary
symptoms, particularly after a recent
instrumentation of catherization.
Physical Findings
• Acute Cystitis:
– Suprapubic tenderness and distension
• Acute Pyelonephritis:
– Fever 104 F
– Abdominal distension, hypotonic bowel sounds,
severe tenderness in lumbar region
Physical Examination
• PE in men should include:
• Inspection and palpation of the genitals for
evidence of urethral discharge, meatal erythema,
inflammation of the glans penis, penile lesions,
enlarged or tender epididymis or testicle, and
inguinal lymphadenopathy.
• A rectal examination with palpation of the prostate
gland should be a standard part of the PE in all men
with UTI symptoms
Diagnostic studies:
• Urinalysis "clean catch“ (midstream)
• Urine Culture & Sensitivity
• When an infection does not clear up with treatment
and is traced to the same strain of bacteria further
tests may be ordered:
• Computed Tomography (CT)
• Ultrasound
• Intravenous Pyelogram (IVP)
• Cystoscope
Diagnostics
• Urinalysis test: urine is examined for white and red
blood cells and bacteria.
• Urine Culture & Sensitivity: bacteria are grown in a
culture and tested against different antibiotics to
see which drug best destroys the bacteria.
• Some microbes, like Chlamydia and Mycoplasma,
can be detected only with special bacterial cultures.
• One of these infections are suspected when there
are symptoms of a UTI and pus in the urine, but a
standard culture fails to grow any bacteria.
Differential Diagnosis
• Acute Bacterial Cystitis should be differentiated
from vulvovaginitis caused by yeast, trichomoniasis
species or bacterial infections
• STDs involving the urethra and cervix such as those
caused by C. trachomatis, N. Gonorrhoeae and
herpes simplex virus.
• Between 10% to 30% of women with STDs or other
forms of vaginitis have frequency and dysuria
Clinical Decision Making:
Differential Diagnosis
Vulvovaginitis: external dysuria, soreness of the vulva,
malodorous vaginal discharge, pruritus and
dyspareunia
• Pyuria and hematuria is rare
• Urine culture reveals less than 10/2 colonies/ml
Urethritis: caused by sexually transmitted pathogensgradual onset of dysuria without other urinary
symptoms, vaginal discharge or bleeding or lower
abdominal pain.
• Pyuria with urine culture showing less than 10/2
colonies/ml
• No hematuria
Clinical Decision Making based on
Laboratory Findings
• Urine Dip Stick:
– bacterial counts >10/5 Enterobacteriaceae/ml of
urine with concomitant pyuria can be detected by
this method
• Microscopic examination of centrifuged urine
can detect the presence of:
significant pyuria (>4 WBCs per high power field),
hematuria (>4 RBCs per high-power field)
or both.
• This provides further support for the diagnosis of
UTI
Clinical Decision Making based on
Laboratory Findings
• Leukocyte casts: strongly support the
diagnosis of pyelonephritis
• Urine culture: identifies pathogenic
microorganism
• 1st a.m. Urine: presence of >1 bacterium per
high-power field on a gram-stained film of
uncentrifuged urine correlates with >10/5
bacterial colonies/ml in 90% of pts
Clinical Decision Making:
Differential Diagnosis
• Presence of pyuria does not differentiate upper
from lower UTIs
• Pyuria in the absence of bacteriuria should raise the
possibility of renal tuberculosis or allergic
interstitial nephritis
• Postmenopausal Women: atrophic changes in
mucosa of the vulvovagina and urethra caused by
hormone deficiency may result in persistent or
recurrent frequency and dysuria
• Renal and genitourinary neoplasms need to be
ruled out
Differential Diagnosis
• Acute Pyelonephritis
– Young female patient should be differentiated
from:
– Pelvic inflammatory disease
– Appendicitis
– Atopic pregnancy
– Ruptured ovarian cyst
Etiology: Risk Factors
• Any abnormality of the urinary tract that obstructs
the flow of urine such as a kidney stone, sets the
stage for an infection.
• An enlarged prostate gland can slow the flow of
urine - raising the risk of infection
• A common source of infection is catheters, or tubes,
placed in the bladder.
• The elderly or those with nervous system disorders
who lose bladder control, may need a catheter for
life
Etiology: Risk Factors
• People with diabetes have a higher risk of a UTI
because of changes in the immune system.
• Immunosuppressed patients are at risk of a urinary
infection.
• For many women, sexual intercourse seems to
trigger an infection
• Women who use a diaphragm are more likely to
develop a UTI than women who use other forms of
birth control.
• Women whose partners use a condom with
spermicidal foam also tend to have growth of E. coli
bacteria in the vagina
Recurrent UTI infections
• Nearly 20% of women who have a UTI will have
another
• 30% of those will have yet another.
• Of the last group, 80 percent will have recurrences.
• Usually, the latest infection stems from a strain or
type of bacteria that is different from the infection
before it, indicating a separate infection.
• Even when several UTIs in a row are due to E. coli,
slight differences in the bacteria indicate distinct
infections.
Uncomplicated UTIs
Organisms Commonly Antibacterial of
Found:
Choice:
Escherichia coli
TMP-SMZ or 1st generation
cephalosporin
Proteus mirabilis
Amoxicillin or TMPSMZ
Klebsiella pneumoniae TMP-SMZ or 1st generation
cephalosporin
Enterococcus faecalis
Amoxicillin
Staphylococcus
saprophyticus
TMP-SMZ or 1st generation
cephalosporin
Complicated UTIs
E-coli, Proteus & Klebsiella 1st, 2nd, or 3rd generation
cephalosporin
Enterococcus faecalis
Ampicillin or vancomycin +
aminoglycoside
Pseudomonas
Antipseudomonal penicillin +
aminoglycoside; ceftazidime;
fluoroquinolone
Enterobacter
Fluoroquinolone; TMPSMZ; Imipenem
Indole-+ Proteus &
Serratia
Acinetobacter
3rd generation
cephalosporin; TMP-SMZ
Staphylococcus
Penicillinase-resistant penicillin
or vancomycin
Imipenem; TMP-SMZ
Clinical Decision Making:
Upper vs. Lower UTI
• Clinical signs and symptoms may not always
be accurate for distinguishing between Upper
and Lower UTIs
• Distinction between them is best assessed by
the response to treatment
Clinical Decision Making:
• UTIs are treated with antibacterial drugs.
• The choice of drug and length of treatment
depend on the patient's history and the urine
tests that identify the offending bacteria.
• The sensitivity test is especially useful in
helping to select the most effective drug.
Acute Uncomplicated Cystitis: Single Dose Treatment
Young
woman, first
episode
•TMP-SMZ
Single Dose
320/1600 mg, 2
double strength
tabs
•Amoxicillin 3gm
•Cephaloridine
2gm
•Gentamicin
5 mg/kg
•Doxycycline
300 mg
Acute Uncomplicated Cystitis:
Short Course Treatment
Young woman, •Trimethoprim
100-200mg q 12 hrs
first episode
•TMP-SMZ 160/800
mg q 12 hrs
•Nitrofurantoin
100 mg q 8 or 6 hrs
•Amoxicillin 250
mg q 8 hrs
•Ciprofloxacin
250-500 mg q 12 hrs
•Norfloxacin 400
mg q 12 hrs
Short course
3 to 5 days
Acute Uncomplicated Cystitis:
•Diabetes
Mellitus
•Symptoms
>7 days
•Age >65 yrs
•Diaphragm
•Trimethoprim
100-200mg q 12 hrs
•TMP-SMZ 160/800
mg q 12 hrs
•Nitrofurantoin
100 mg q 8 or 6 hrs
•Amoxicillin 250
mg q 8 hrs
•Ciprofloxacin
250-500 mg q 12 hrs
•Norfloxacin 400
mg q 12 hrs
7 to 10 days
Acute Uncomplicated Cystitis
Young healthy •Trimethoprim
100-200mg q 12 hrs
man
•TMP-SMZ 160/800
mg q 12 hrs
•Ciprofloxacin
250-500 mg q 12 hrs
•Norfloxacin 400
mg q 12 hrs
7 to 10 days
Recurrent Cystitis
•TX based on
sensitivity results
•R/O renal stones,
Scars, cysts,
Chronic Bacterial
Prostatitis
14 days
<2 episodes/yr
TX as 1st episode in
young woman
Single dose or 3-5
days
>3 episodes/yr
TMP+SMZ,
amoxicillin,
Nitrofurantoin,
ciprofloxacin or
Norfloxacin,
followed by lowdose antibiotic
prophylaxis
3-5 days, then 1 yr of
prophylaxis
Relapses
Reinfection:
Recurrent Cystitis
Temporally
related to
coitus
Postmenopause
TMP+SMZ,
Postcoital
Nitrofurantoin prophylaxis
cephalexin;
voiding after
intercourse
Topical
estradiol
cream+lowdose antibiotic
prophylaxis
Asymptomatic Bacteriuria
With/without
catheter
No TX unless
Pregnancy
Amoxicillin/Ampicillin,
Nitrofurantoin oral
cephalosporin
10 – 14 days
symptomatic,
neutropenic, renal
transplant, urea
splitting bacteria,
obstruction, diabetes
mellitus, sickle cell
disease/trait,
NSAID/analgesic abuse
3 – 5 days
Acute Uncomplicated Pyelonephritis
Very sick or
septic
Parenteral: TMP-SMZ,
ciprofloxacin,
ceftriaxone, or
gentamicin+ampicillin
until afebrile, then
oral regimen
14 days; if
relapse,
6 weeks
Not very sick
Oral: TMP+SMZ,
amoxicillin,
ciprofloxacin,
Norfloxacin
14 days; if
relapse,
6 weeks
Pregnancy
Parenteral:
ceftriaxone,
gentamicin+ampicillin
, aztreonam, or TMPSMZ until afebrile,
then oral regimen
14 days
Symptomatic Complicated Upper UTI
Very sick or
septic
Parenteral:
gentamicin+ampicilli
n, ceftriaxone,
aztreonam,
imipenem-cilastatin,
ciprofloxacin,
ticarcillinclavulanate
2 – 3 week; if
relapse,
6 weeks
Not very sick
Oral: ciprofloxacin,
Norfloxacin, or
TMP-SMZ (if
sensitive)
2 – 3 week; if
relapse,
6 weeks
Patient Education
• Teach proper hygiene: Women wipe from front to
back to prevent bacteria around the anus from
entering the vagina or urethra.
• Take showers instead of tub baths
• Encourage patient to increase fluid intake and avoid
of bladder irritants such as caffeine, smoking and
alcohol.
• Recommend cranberry juice that may decrease
bladder colonization
• Encourage patient to urinate when he/she feels the
need
Patient Education: Continue
• Advise voiding before and after sex
• Cleanse the genital area before and after sexual
intercourse.
• Recommend alternative methods of contraception
for women using diaphragms if recurrent infections
exist
• Avoid using feminine hygiene sprays and scented
douches, which may irritate the urethra.
• Discuss the need to complete entire course of
medication
Follow-up & Referrals
Follow-up:
• Repeat U/C after completion of medication
• Advise pt to return if s/s increase in severity or fail to
improve after 3 days of therapy.
Consultation/Referral if:
• Renal Calculi are suspected
• Infection persists after two courses of appropriate
treatment
• If pyelonephritis is suspected
• If patient has insulin dependent diabetes
• When patient has existing renal disease
• History of 3 UTIs in one year