Uncomplicated Urinary Tract
Infection
Jayme Bristow
PharmD Candidate
UGA COP
UTI
UTI is the most common bacterial infection
in the ambulatory care setting in the US
8.6 million visits in 2007
84% of those were women
Causes
 UTIs typically occur when bacteria outside the body enter the
urinary tract through the urethra and begin to multiply
 The bladder secretes a protective coating that prevents
bacteria from attaching to its wall
 Urine also has antibacterial properties that inhibit the growth
of bacteria
 Bacterial bladder infections may occur in women as a result of
sexual intercourse. During sexual activity, bacteria may be
introduced into the bladder through the urethra
 Women are susceptible to lower urinary tract infections
because the female genital area often harbors bacteria that
can cause cystitis
 Most cases of cystitis are caused by Escherichia coli (E. coli),
a species of bacteria commonly found in the genital area
Risk Factors
 Are sexually active: sexual intercourse can result in bacteria being
pushed into the urethra
 Use certain types of birth control: women who use diaphragms
are at increased risk of a UTI. Diaphragms that contain spermicidal
agents further increase your risk
 Are pregnant: Hormonal changes during pregnancy may increase
the risk of a bladder infection
 Interference with the flow of urine: this can occur in conditions
such as a stone in the bladder or, in men, an enlarged prostate
 Changes in the immune system: this can occur with conditions
such as diabetes, HIV infection and cancer treatment
 Prolonged use of bladder catheters: prolonged use can result in
increased vulnerability to bacterial infections as well as bladder
tissue damage
Non-Risk Factors
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Precoital or postcoital voiding patterns
Daily beverage consumption
Frequency of urination
Delayed voiding habits
Wiping patterns
Tampon use
Douching
Use of hot tubs
Type of underwear
Body mass index
Cystitis vs Pyelonephritis
Cystitis is the medical term for
inflammation of the bladder
Most of the time the inflammation is
caused by a bacterial infection
In which case it may be referred to as a urinary
tract infection
Cystitis vs Pyelonephritis
Symptoms of cystitis include:
A strong, persistent urge to urinate
A burning sensation when urinating
Passing frequent, small amounts of urine
Blood in the urine (hematuria)
Passing cloudy or strong-smelling urine
Discomfort in the pelvic area
A feeling of pressure in the lower abdomen
Low-grade fever
Cystitis vs Pyelonephritis
Kidney infection (pyelonephritis) is a
specific type of urinary tract infection (UTI)
that generally begins in your urethra or
bladder and travels up into your kidneys
Kidney infection can permanently damage
your kidneys or the bacteria can spread to
your bloodstream and cause a lifethreatening infection
Cystitis vs Pyelonephritis
Symptoms of pyelonephritis include;
Fever
Nausea/Vomitting
Back, side (flank) or groin pain
Abdominal pain
Frequent urination
Strong, persistent urge to urinate
Burning sensation or pain when urinating
Pus or blood in your urine (hematuria)
With or without symptoms of cystitis
Microbiology
E. coli causes 75 to 95% of episodes of
uncomplicated cystitis and pyelonephritis
The remaining cases are caused by other
Enterobacteriaceae ( Klebsiella
pneumoniae) or grampositive bacteria:
Staphylococcus saprophyticus
Enterococcus faecalis
Streptococcus agalactiae (group B
streptococcus)
Diagnosis
 Assessment for pyuria and bacteriuria is often
performed with the use of commercially
available dipsticks
 Test for leukocyte esterase:
Enzyme released by leukocytes
 Test for nitrites:
Some bacteria reduce urinary nitrates to nitrites
 Urine culture is performed to confirm the
presence of bacteriuria and antimicrobial
susceptibility of the infecting uropathogen
Management – Cystitis
 Antimicrobial drugs are routinely prescribed, the
primary goal being the rapid resolution of
symptoms
 Choice of regimen has become more
complicated as resistance among the
uropathogenic strains of E. coli has increased
worldwide
 Rates of resistance to amoxicillin of 20% or
higher in all regions and similar rates of
resistance to trimethoprim– sulfamethoxazole in
many regions
Management – Cystitis
The choice of an antimicrobial agent
should be individualized on the basis of:
The patient’s allergy and compliance history
Local practice patterns
The prevalence of resistance in the local
community (if known)
Availability
Patient and provider threshold for failure
Management – Cystitis
If a first-line antimicrobial agent is not a
good choice on the basis of one or more of
the previously mentioned factors,
fluoroquinolones or beta lactams are
reasonable alternatives
It is preferable to minimize their use
because of concerns about ecologic
adverse effects and, with respect to betalactams, efficacy
Management – Pyelonephritis
 Most episodes of acute uncomplicated
pyelonephritis are treated as outpatients
 Culture and susceptibility test should be
performed to guide treatment
 Women should be admitted if:
Pyelonephritis is severe
Hemodynamic instability
Any complicating factor
Oral medications are not tolerated
There is concern regarding potential nonadherence
Recurrence – Cystitis
Urinary symptoms that persist or recur
within a week or two of treatment for
uncomplicated cystitis suggest infection
with an antimicrobial-resistant strain or,
rarely, relapse
Urine culture should be performed and
treatment should be initiated with a
broader-spectrum antimicrobial agent,
such as a fluoroquinolone
Recurrence – Cystitis
 The vast majority of episodes of recurrent
cystitis in healthy women, up to two thirds of
which are recurrences involving the same strain
of bacteria that caused the initial infection, are
thought to be reinfections
 Uropathogenic strains can persist in the fecal
flora for years after elimination from the urinary
tract and can cause recurrent urinary tract
infections
Follow Up
 Urine culture is unnecessary if symptoms have resolved,
except in pregnant women for whom treatment of
persistent asymptomatic bacteriuria is recommended
 Women with pyelonephritis who have;
Severe or worsening illness
Persistent fever 48 to 72 hours after the initiation of
appropriate antimicrobial treatment
Symptoms suggestive of a stone, abscess, or
obstruction
 Urologic evaluation should be performed to rule out
these latter abnormalities
References
 “Uncomplicated Urinary Tract Infections.” N Eng
J Med 2012;366:1028-37.
 “Cystitis.” MayoClinic. Accessed 6 May 2012.
http://www.mayoclinic.com/health/cystitis/DS002
85/DSECTION=complications
 “Pyelonephritis.” MayoClinic. Accessed 6 May
2012. http://www.mayoclinic.com/health/kidneyinfection/DS00593