What is a UTI?
Urinary Tract Infection (UTI) is presence of microorganisms in the urinary tract that are not attributed to contamination
What is a LOWER UTI?
CYSTITIS
"bladder infection" - usually not associated with systemic symptoms. They are more localized.
What is a UPPER UTI?
PYELONEPHRITIS
"kidney infection" - could result in sepsis or septic shock.
______ is an infection in the prostate.
Prostatitis
Can be acute or chronic
What is the most common causative pathogen of UTI?
E. Coli.
What qualifications allow for a UTI to be considered uncomplicated?
No structural abnormalities
No instrumentation or catheters
Healthy women
Not pregnant = pregnancy automatically classifies as complicated.
What qualifications allow for a UTI to be considered complicated?
Presence of structural abnormalities
Catheterization
(Foley catheter
Suprapubic catheter)
Men
Immunocompromised
Pregnant women
NOTES on UTI:
Most commonly occurring bacterial infections
60% of females will get at least one UTI during their lifetime
20-25% will have recurrence within one year
UTIs are less common in men until they reach age > 65 years
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What are the protective properties of urine (that keep urine sterile)?
Acidic pH
High osmolality
High concentration of urea
Bacteria in the bladder induce the need to _____.
VOID
Prostate secretions contain an antibacterial factor that is _______ to most pathogens
bactericidal
Low vaginal pH reduces _____ _____.
Bacterial colonization
_____ infection is where the bacteria enters from the urethra and move into the bladder or kidney.
Ascending
Women at higher risk due to short urethra and proximity of urethra to vagina and anus
______ infection is when the bacteria enters the kidney or bladder from the bloodstream. EX: S. aureus
Hematogenous
T/F Staph aureus is NOT a typical urinary tract pathogen, BUT if you have bacteremia with staph aureus, you can sometimes see it in the urine.
True
What are the risk factors of UTI?
Sexually active
Unable to void (obstruction)
Urinary catheterization
Instrumentation
Pregnancy
Nephrolithiasis (kidney stone).
E. Coli is a _____ ____ that is a gram negative rod.
Lactose fermenter
Other than E. Coli, what other gram negative rods could cause UTI?
Klebsiella pneumoniae
Proteus mirabilis
Pseudomonas aeruginosa
STAPH saprophyticus could also cause
What are the signs and symptoms of cystitis?
Dysuria
Frequency
Urgency
What are the signs and symptoms of pyelonephritis?
Dysuria
Frequency
Urgency
Flank pain
Fever/ chills
systemic signs of infection
Costovertebral tenderness MD will tap on flanks where kidneys are patient is jumpy.
How are urine specimens collected, and which is the most frequently used?
Clean catch - collect urine midstream. Examine within 2 hours
Catheterized specimen - do not take urine from the bag. May need to straight catheterize a patient.
Suprapubic specimen
Clean catch is the most frequently used.
What would a urinalysis show for patients with a UTI?
Clarity - CLOUDY
Blood - POSITIVE
Nitrite - POSITIVE
Leukocyte esterase - POSITIVE
What is the most specific in the urinalysis and what is the most sensitive.
Most specific = nitrites
Most sensitive = Leukocyte enterase
KNOW: Nitrites - if positive it is associated with infection. Bacterial involvement, it is specific but not sensitivity. If you have it, it is likely that you have bacteria in your urine if posi
____ ____ is how concentrated the urine is.
Specific gravity
T/F Most UTIs affect the urine's pH.
False
The only one that does is proteus mirabilis and it increases the pH
What is the threshold for WBCs on a urine microscopy?
WBC > 5-10
Put urine on slide and look at it under the microscope
Positive leukocyte esterase should have more than 10 WBCs when you look at urine under a microscope.
Blood on the UA expect to see it under the microscope. Likely talking about myoglobin
Urine microscopy in UTI. May see:
WBC
Positive RBC?
Few epithelial cells
Triple phosphate crystals- proteus species
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T/F A urine culture is required to make a diagnosis of a UTI.
False
Usually urine culture is reserved for patients that are hospitalized or do not respond to initial therapy. Urine culture is NOT required to make a diagnosis.
Urine culture:
Greater than 100,000 organisms
Gram stain
Definitive organism
Susceptibility report
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Host factors related to agent selection for UTI:
Site of infection (bladder, kidney, bacteremia?)
Primary pathogens
Allergies
Age
Sex
Renal impairment
Pregnant (Y/N)
Drug factors related to agent selection for UTI:
Tissue penetration (bladder concentration vs. kidney)
PK/PD
Concentration in the urine?
Dosing interval
Toxicity
Cost
Drug/drug interactions
What is the primary treatment for uncomplicated cystitis in women? This is for young, healthy, non-pregnant women that are outpatient.
Drugs of choice:
Nitrofurantoin monohydrate/macrocrystals (Macrobid): 100 mg po BID x 5 days
SMX/TMP 800mg/160mg (Bactrim DS): 1 tablet po BID x 3 days
Avoid use if resistance is >20% in local areas or if used in the past 3 months for a UTI
Alternative
Fo
What is the treatment for uncomplicated pyelonephritis in women? This is EVIDENCE of kidney involvement but WITHOUT clinical decompensation.
Drug of choice
Ciprofloxacin 500 mg po BID x 7 days (AI)
Levofloxacin 750 mg po QD x 5 days (BII)
Avoid if community EColi resistance is > 10%
Alternatives
Ceftriaxone 1g IV every 24 hours x 10-14 days
SMX/TMP 800mg/160 mg po BID x 14 days
T/F Empiric amoxicillin and augmentin are ideal treatments for UTI.
FALSE
Empiric amoxicillin and amoxicillin/clavulanate should be avoided due to high resistance
What is the preferred treatment of UTI?
Nitrofurantoin preferred due to minimal resistance and decreased "collateral damage
T/F Moxifloxacin is a good choice for a UTI.
FALSE
_______ are effective but should be reserved for pyelonephritis due to high risk for "collateral damage". Name two drugs.
Fluoroquinolones (levofloxacin & ciprofloxacin)
T/F Ampicillin susceptible strain will also be susceptible to amoxicillin.
True
NOTES:
What about phenazopyridine hydrochloride?
OTC or Rx (Pyridium)?
Azo dye used as urinary antiseptic, analgesic
100-200 mg PO TID with food x 2 days
Does not kill bacteria
Discolors urine red or orange
Not in patients with CrCl < 50 ml/min
Risk of me
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What color does Pyridium change the urine?
Red or orange
What about cranberry for UTI?
Can decrease the ability of the bacteria to stick to the bladder wall.
NOTE: Warfarin interacts -
reports of significantly elevated INR. Concentrated capsules can produce this D-D interaction, no so much the concentration in the juice.
Will not stop the U
Patient education:
Empty bladder frequently
Drink 6-8 glasses of water daily
Avoid bubble bath, feminine hygiene sprays, douching,
Empty your bladder after intercourse
Minimize use of spermicides
Wipe from front to back after toileting
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