EXAM 3 UTIs Flashcards
what is bacteriuria?
- bacteria in urine
- often colonization, not infection
what is a UTI?
bacterial infection of lower or upper urinary tract
what is acute cystitis?
- bacterial infection of the bladder
- infection (and symptoms) confied to lower urinary tract
what is acute pyelonephritis?
bacterial infection of upper urinary tract (ureters, renal pelvis, kidney parenchyma)
what are criteria of uncomplicated UTIs?
- not pregnant
- normal urinary anatomy
- no co-morbitities (healthy, outpatient)
- *patients with uncomplicated UTIs should meet ALL of these criteria
what are the criteria for complicated UTIs?
- pregnant
- abnormal urological anatomy or function
- diabetes melitis
- immune compromise
- indwelling bladder catheter
- male gender
- *patients should be diagnosed with complicated UTI if they meet ANY of these criteria
by age ___, half of women have had at least one UTI
32
cystitis (lower UTI) is more common than pyelonephritis (upper UTI)
UTI develops in >___% of patients with indwelling urinary catheters
10
in healthy individuals in the absence of infection, which bacteria typically colonizes the lower urinary tract?
A. s. aureus
B. proteus species
C. eschericia coli
D. none of the above
D. none of the above
in young healthy individuals, the urinary tract should be sterile
T or F
the urinary tract is normally sterile in young, healthy patients
true
85% of bacteria that cause UTIs are ___ colonizers of the GI tract
gram negative
what are the main bacteria that cause UTIs that are gram negative colonizers of the GI tract
- e. coli (predominant pathogen in UTIs: 75-95%)
- proteus mirabilis
- klebsiella pneumoniae
- staphylococcus saprophyticus
describe the pathogenesis of UTIs
- GI pathogens colonize peri-urethral mucosa
- ascend through urethra to bladder
- urethra is shorter in women than men
- prostatic fluid has anti-bacterial properties
- continue to ascend to ureters/kidney
- less clear how this occurs
- most untreated lower UTI will not progress to pyelonephritis
uropathogenic e. coli have multiple virulence factors. what are they?
- pili
- flagella
- adhesins
- siderophores
- toxins
- polysaccharide coating
the following symptoms are suggestive of what type of UTI?
pain or burning with urination (dysuria)
increased frequency of urination
increased urgency of urination
suprapubic pain
cystitis (lower UTI)
the following symptoms are suggestive of what type of UTI?
fever (>38.3*C)/ chills
flank or costo-vertebral angle pain
nausea/vomiting
pyelonephritis
can also have +/- symptoms of cystitis
what is the gold standard for diagnosis of UTIs?
- symptoms + urine culture demonstrating >105 colony-forming units of uropathogenic bacteria per mL
a positive culture without symptoms = ___?
asymptomatic bactereuria
important distinction to make as this changes management (no antibiotics for asymptomatic bacteriuria)
describe a normal urinalysis
- specific gravity = urine density/ density of water
- nitrite negative = metabolic byproduct of some uropathogenic bacteria
- RBCs and WBCs in urine should be less than 5 per high power field
- some labs also report leukocyte esterase - a surrogate for presence of WBCs
describe an abnormal urinalysis
- cloudy urine with increased specific gravity
- presence of nitrites suggest nitrogen-metabolizing organisms are present
- hematuria and pyuria present
what is the purpose of UA (urinalysis) / microscopy utility for UTI diagnosis?
to rule out UTI based on absence of pyuria (<10 WBC/hpf or negative leukocyte esterase)
when is obtaining UA or microscopy not necessary for UTI diagnosis?
when specific UTI signs or symptoms are clearly present or absent
___ alone is not an indication for antibiotics.
pyuria
it is not specific to UTI or sufficient to differentiate symptomatic UTI from asymptomatic bacteriuria
pyuria is common in patients with ___
asymptomatic bacteriuria
UTI symptoms are highly predictive of disease in what population?
young healthy patients
not every patient needs urine evaluation
T or F:
lower bacterial colony counts are insignificant
false
they may be significant in a few instances
diagnostic work up should depend on ___
- illness severity and likelihood of other diagnoses
- recurrent UTI (resistant organism?)
- vaginal symptoms (is there a possibility of sexually transmitted infection?)
- do not send urine cultures in patients without clinical symptoms
can uncomplicated cystitis resolve itself without the use of antibiotics?
- yes, it generally does
- antibiotics are used to provide symptom relief
what are 3 antibiotics that can be given for uncomplicated cystitis?
- nitrofurantoin
- trimethoprim-sulfa methoxazole (TMP/SMX)
- fosfomycin
- remember, these are used to provide symptom relief only and actually have minimum “ecologic effects”
what are 3 drugs that can be given for uncomplicated pyelonephritis?
- fluoroquinolones (ciprofloxacin or levofloxacin)
- trimethoprim-sulfa methoxazole (TMP/SMX)
- beta lactams (ceftriaxone, cefepime)
if a patient with uncomplicated pyelonephritis is unstable (hemodynamic instability, cannot take PO, severe symptoms), what should be done?
they should be admitted to the hospital for IV antibiotics
e. coli resistance to ___ is not >20% worldwide
amoxicillin
___ resistance is 20% and rising quickly
fluoroquinolone
___ antibiotics will have major ecologic effect by killing normal GI flora (collateral damage)
broad spectrum
this has lead to a trend toward prescribing narrower spectrum antibiotics
is there a need for antibiotics in asymptomatic bacteriuria?
- no, unless:
- patient is pregnant
- pre-urology procedure
- renal transplant
- neutropenic
- antibiotics do not decrease asymptomatic bacteriuria or prevent subsequent development of UTI
what is the prevalence of asymptomatic bacteriuria in healthy pre-menopausal women?
1-5%
what is the prevalence of asymptomatic bacteriuria in post-menopausal women?
2.8-8.6%
what is the prevalence of asymptomatic bacteriuria in diabetic women?
9-27%
what is the prevalence of asymptomatic bacteriuria in female long term care residents?
25-50%
what is the prevalence of asymptomatic bacteriuria in male long term care residents?
15-40%
describe the cost of unnecessary Rx and missed diagnosis
- drug-drug interactions
- renal and other complications
- drug allergies
- c. difficile infection
- missing the real diagnosis
- no improvement in UTIs
- increased risk of developing resistant organisms in your patient
a patient is admitted with an indwelling bladder catheter. urine culture reveals >105 Cfu e. coli. there are no urinary symptoms and the patient feels well. what is the best management?
A. remove catheter if possible, no other treatment
B. initial broad spectrum antibiotic
C. change the catheter and re-culture
D. start a low-dose long-term antibiotic while catheter is in place
A. remove catheter if possible, no other treatment
what are the symptoms of catether-associated UTIs?
- usually lack typical UTI symptoms
- new fever with no other source
- CVA tenderness, flank pain, pelvic discomfort
describe the diagnosis of catheter-associated UTI
- presence of inflammation on urinalysis (pyuria) doesn’t correlate with infection
- absence of pyuria rules out CA-UTI
- urine culture with >/= 105 cfu bacteria
- UA/culture must be interpreted based on clinical scenario
what is the treatment for CA-UTI?
- remove catheter whenever possible
- replace catheters that have been in >/= 2 weeks if still indicated
- antibiotic duration
- 7 days if prompt response
- 3 days if catheter removed in female patient with no evidence of associated pyelonephritis
what is the relationship of bacteriuria to asymptomatic bacteriuria and catheter-associated UTI?
- bacteriuria
- patient without urinary catheter
- ASB or UTI
- patient with urinary catheter
- ASB or CA-UTI
- patient without urinary catheter
- bacteriuria means a positive urine culture
