IC13 PR3151 UTI Flashcards
What is asymptomatic bacteriuria?
isolation of significant colony counts of bacteria in the urine without UTI symptoms
Difference between asymptomatic bacteriuria VS UTI?
Both have isolation of significant colony count but UTI displays symptoms.
What is the spectrum of UTI
Cystitis
Pyelonephritis
Eventually UTI with bacteremia/sepsis/death.
When is screening for asymptomatic bacteriuria done?
1) pregnant women
2) patients going for urologic procedure where mucosal trauma or bleeding is expected e.g., TURP (transuretal/rectal removal of prostate), cystoscopy w biopsy
Why is screening and treatment for asymptomatic bacteriuria not commonly done?
E.g., elderly in long term care, spinal cord, indwelling catheter use –> treatment did not decrease risk of subsequent UTI in these groups.
Indications for screening and treatment of asymptomatic bacteriuria in pregnant women?
and when to screen?
To prevent pyelonephritis (about 20% chance), preterm labor, infant low birth rate.
Screen at first visits (12-16 wk gestation)
If bacteriuria: treat with active abx based on AST for 4-7 days.
Indications for screening and treatment of asymptomatic bacteriuria in patients undergoing urologic procedure with possible mucosal trauma/bleeding?
and when to screen?
what to do if confirmed bacteriuria
Prevent post-operative bacteremia and urosepsis
Screen prior to procedure.
If bacteriuria: treat as SAP.
THEN
obtain culture and treat based on culture and AST
When to initiate treatment of ASB/UTI during mental status change?
When delirium, falls, confusion symptoms appear in the presence of urinary symptoms + systemic symptoms
What is the anatomical classification of UTI?
Upper:
- pyelonephritis (kidney)
Lower:
- cystitis (bladder)
- urethritis (urethra)
- prostatitis (prostate)
- epididymitis (epididymis)
Catheter associated
What is the epidemiology of UTI (age and prevalence factors)
older age increases prevalence.
0-6 months –> males > females due to higher rate of structural and functional abnormalities
1yo - adult –> females > males because of shorter urethra + abx properties of male prostate
> 65 –> equal risk due to increased comorbidities e.g., BPH, urine incontinence from muscular dysfunction, stroke…
What is the pathogenesis of ascending UTI?
Colonic or fecal flora colonise periurethra area/urethra and ascends to bladder and kidney
What are the risk factors of ascending UTI?
Females due to shorter urethra, use of spermicides, diaphragm contraceptive.
What are the organism examples for ascending UTI?
E K P
e coli
klebsiella
proteus
What is the pathogenesis of descending (hematogenous) UTI?
organ at distant primary site (heart valve, bone) travel through blood stream (bacteremia) to the urinary tract causing UTI
What are the organism examples for descending (hematogenous) UTI?
S. aureus,
Mycobact TB
What are the three factors determining UTI development?
1) Host defence mechanism
2) Size of incolum (bact load)
3) Virulence/pathogenicity of microorganism
What are the methods in host defence mechanism for preventing UTI?
1) antibact properties of urine and prostatic secretion.
2) anti adherence mechanisms of bladder
3) infl response with polymorphonuclear leukocytes (PMNs) –> phagocytosis –> prevent control spread.
4) bacteria in bladder will stimulate micturition and increased diuresis
How does size of inoculum affect UTI dev?
obstruction and urinary retention
What are some virulence/pathogenicity factors increasing dev of UTI (RE: Ecoli)
E.G., E COLI resistant to washout or removal by antiadherent mechanism of bladder.
Risk factors for UTI? (x11)
Females > males
Sexual intercourse
UT abnormality (BPH, kidney stone,
urethral stricture, Vesicoureteral reflux)
Neurologic dysfunction (stroke, diabetes, spinal cord inj)
Anti cholinergic drugs (1st gen antihistamines, atropine)
Catheterisation and other mechanical instrumentation
Diabetes (neuropathy + glycosuria)
Pregnancy
Use of diaphragm/spermicide contraceptive (alter flora)
Genetic association (positve fam hist)
Previous UTI
Non-phx methods to prevent UTI?
1) Drink lots of fluids 6-8cups
2) Urinate frequently
3) Urinate shortly after sex
4) Wipe from front to back for women, esp after bowel movement
5) Cotton underwear and loose fitting clothes to keep area dry.
6) modify birth control if using spermicide or diaphragm
What are the two classifications of UTI?
uncomplicated and complicated.
Classification of uncomplicated UTI?
usually in pre menopausal, non pregnant (healthy) women with no history suggestive of abnormal urinary tract
usually ambulatory women
Classification of complicated UTI?
usually associated w serious outcomes and risk for therapy failure
uti in men, children, pregnant women
presence of complicating factors/risk factors: functional and structural abnormalities of UT, genitourinary instrumentation, DM, immunocompromised host
Clinical spectrum of complicated UTI?
mild cystitis to life threatening urosepsis
subjective symptoms of lower UTI (cystitis)?
dysuria, urgency, frequency, nocturia, suprapubic heaviness or pain, gross hematuria (blood in urine)
subjective symptoms of upper UTI (pyelonephritis)?
fever, rigor, headache, N/V, malaise, flank pain, costovertebral tenderness(renal punch), abdomen pain
note that pyelonephritis more likely to present with systemic symptoms of infection as well.
how to obtain objective parameters for UTI? what are the 3 methods of XX
urinalysis and culture:
3 methods
1) midstream clean catch
2) catheterization
3) suprapubic bladder aspiration
What is in the UFEME report for objective clinical diagnosis?
WBC
- >10 wbcs/mm3 = pyuria (pus in urine)
- presence of inflammation
RBC
- >5/HPF or gross = hematuria
- frequently in uti but non-specific
Microorgs
- bact or yeast w gram stain
WBC casts
- masses of cells/proteins that form in renal tubules indicate upper tract infection
Clinical spectrum of uncomplicated UTI? i.e. problem
Mild cystitis to severe pylonephritis
What does the chemical urinalysis (dipstick) test?
1) nitrite
2) leukocyte esterase
Level of WBC indicating pyuria?
> 10wbc/mm3
Level of RBC indicating hematuria?
microscopic >5/HPF or gross
Level of bacteria to indicate positive nitrite test (dipstick)?
10^5 bacteria/mL
What does the nitrite level test in dipstick test?
gram negative bact
it reduces nitrate to nitrite
How do false negative results appear in nitrite test (dipstick)?
G(+) orgs and pseudomonas
Low urinary pH
frequent voiding
dilute urine
What does the LE level show in dipstick test?
esterase activity of leukocytes in urine, which correlates with pyruia (>10wbc/mm3)
When to and not to obtain urine culture?
Not needed in uncomplicated cystitis
Needed in
pregnancy
recurrent uti
pyelonephritis
catheter associated uti
all men with uti
What are the likely pathogens for uncomplicated or comm acquired UTI?
Ecoli (85%)
Staph Saprophytic (5-15%)
Others:
Enterococcus faecalis
Kleb pneu
proteus
What are the likely pathogens for complicated or hospital acquired UTI?
E coli (50%)
enterococci
proteus, kleb sbb, enterobacter spp
pseudo aeruginosa
what are the other misc pathogens for UTI?
staph aureus (bacteremia associated from other primary site)
yeast/candida (contaminant?)
what are some healthcare associated risk factors that may result in HA-UTI/complicated UTI?
usually recent or frequent exposure to HC settings.
recent hospitalisation, recent ABX use, recent invasive urological procedure, use of long term catheter
what is the first line empiric abx for cystitis in women (uncomplicated)
PO cotrimoxazole 800/160 mg bid x 3d (check crcl > 30ml/min)
PO nitrofurantoin 50mg qid x 5d
(not for pyelonephritis because poor distribution to kidney tissues)
PO fosfomycin 3g single dose
(rarely used unless ESBL/more resistant organisms without oral options)
what is the alternative empiric abx for cystitis in women (uncomplicated)
PO beta lactams 5-7 days
- po cefuroxime 250mg bd
- po amoxiclav 625mg bd
- po cephalexin 250-500mg QDS
PO fluoroquinolones 3 days
- po cipro 250mg bd
- po levo 250mg od
all the doses stated are halved
what are the empiric abx for complicated cystitis in women
same as uncomplicated by treat for 7-14 days instead
ONLY fosfomycin dose changed to PO 3g EOD x 3 doses
what is the first line empiric abx for pyleonephritis in women (community acquired) (uncomplicated)?
PO fluoroquinolones
* PO ciprofloxacin 500 mg BD x 7 days or
* PO levofloxacin 750 mg OD x 5 days
PO co-trimoxazole 160/800 mg BD x 10-14 days
PO Beta-lactam x 10-14 days
* PO cefuroxime 250-500 mg BD
* PO amoxicillin-clavulanate 625 mg TDS
* PO cephalexin 500 mg QDS
(severely ill) what is the first line empiric abx for pyleonephritis in women (community acquired) (uncomplicated)?
Change to IV agents then deescalate to oral once improved or oral okay
IV ciprofloxacin 400mg BD
or
IV cefazolin 1g q8h
or
IV amoxi-clav 1.2g q8h
and/or IV/IM gentamicin 5mg/kg for more severe infection spreading to the blood (to expand spectrum)
what are the empiric abx for (complicated) (community acquired) cystitis in men?
no concern for prostatitis
same as empiric for complicated cystitis for women but longer duration
what are the empiric abx for (complicated) (community acquired) cystitis in men?
with concern for prostatitis
PO ciproflox 500mg BD
or
PO cotrimoxazole 160/800mg BD
for 10-14 days up to 6 weeks if prostatitis confirmed
What are the definitions of nosocomial and healthcare-associated pneumonia
nosocomial
- onset of UTI >48h post hospital admission
healthcare associated
- patients who have been hospitalised or underwent invasive urological procedures in the last 6 months, has an indwelling urine catheter, exposure to abx, etc
what are the empiric abx for (complicated) (healthcare associated) UTI?
USE broader spectrum to cover for pseudomonas and esbl producing ecoli, kleb
Duration of treatment is 7-14 days
IV cefepime 2g q12h +/- IV amikacin 15mg/kg/d or
IV imipenem 500mg q6h or IV meropenem 1g q8h
PO levofloxacin 750mg (for less sick patients)
PO ciprofloxacin 500mg bid (for less sick patients)
what is the definition of catheter associated uti
s/sx of uti with no other source of infection
10^3 cfu of ONE or more bacterial species in a single catheter urine specimen
patient in indwelling urethral, indwelling suprapubic, intermittent catheterization
OR
voided midstream urine sample in patient who just removed catheter in last 48 hours
what are the risk factors for catheter associated uti?
1) duration of catheterisation
2) Colonisation of drainage bag, catheter and periurethral segment
3) DM
4) Female
5) Renal function impairment
6) Poor quality of catheter care, including insertion
what are the causative organisms for catheter associated uti? (short and long term)
short term
<7 days
85% single org
long term
>28 days
95% polymicrobial (2-3)
when and method to initiate treatment for catheter associated uti?
remove catheter, esp if indwelling catheter placed for >2 wks at the onset of CA UTI and is still indicated –> should replace to hasten recovery
initiate abx after urine sample taken.
initiate only when symptomatic.
consider observation if low-grade fever and patient is stable.
what are the empiric abx for catheter associated UTI?
for 7 days (prompt resolution, no fever after 72h) and 10 - 14 days (delayed response)
IV imipenem 500mg q6H or IV meropenem 1g q8h
IV cefepime 2g q12H +/- IV amikacin 15mg/kg (1 dose or daily)
PO/ IV levofloxacin 750mg x 5d (for mild CA-UTI)
PO Co-trimoxazole 960mg bid x 3d
what are the non phx strategies for catheter associated UTI?
Avoid unnecessary catheter use
Use for minimal duration
Long-term indwelling catheters changed before blockage is likely to occur
Use of closed system
Ensure aseptic insertion technique
Topical antiseptic or antibiotics not recommended
Prophylactic antibiotics and antiseptic not recommended
Chronic suppressive antibiotics is not recommended.
What ABX should be avoided for UTI in pregnancy?
Cipro
Cotrimoxazole (1st and 3rd trimester)
Nitrofurantoin (38-42wks)
Aminoglycosides w caution
What is the reason to avoid ciprofloxacin in pregnancy?
Reports of fetal cartilage damage and arthropathies in animal studies (not confirmed in humans)
What is the reason to avoid COTRIMOX in pregnancy?
first sem: folate antagonism of TMP can cause neural tube defects.
third sem: possible risk of kernicterus in newborns from competitive binding between bilirubin and sulfonamides to plasma albumin.
concern for fetus being G6PD def
What is the reason to avoid nitrofurantoin in pregnancy?
concern for fetus being G6PD def
What is the reason to caution aminoglycoside use in pregnancy?
8th cranial nerve toxicity in fetus reported with older aminoglycosides.
What is the first line abx tx of UTI in pregnancy?
beta lactams
what is the dosing for cephalexin in cystitis
po 250-500mg qds x 5-7 days
what is the dosing for cephalexin in pyelonephritis
po 500mg qds x 10-14days
what are the contra/precaution/preg/adr considerations for cephalexin?
Similar R1-side chain as amoxicillin/ampicillin, risk
of cross-sensitivity for penicillin allergy, avoid in
patient with true penicillin allergy. Generally safe in
pregnancy
ADR: GI
what are counselling points for cephalexin?
Take without regards to
food, if GI discomfort,
take with food.
what is the dosing for cotrimox in cystitis (women)
PO 960mg bd
x 3d
what is the dosing for cotrimox in cystitis (men)
PO 960mg bd x
7-14d
what is the dosing for cotrimox in pyelonephritis
PO 960mg bd
x10-14d
what are the contra/precaution/preg/adr considerations for cotrimox?
Avoid in sulpha allergy, G6PD def, 1st & 3rd
trimester pregnancy, CrCl < 15ml/min.
ADR: nausea, vomiting, myelosuppression, SJS,
hyperkalemia, hepatotoxicity, photosensitivity
what are counselling points for cotrimox?
N/V (take after food),
photosensitivity,
adequate hydration to
prevent crystalluria,
Discontinue at first sign
of rash.
what is the dosing for cipro in cystitis (women)
PO 250mg bd
x 3d
what is the dosing for cipro in cystitis (men)
PO 500mg bd x
7-14d
what is the dosing for cipro in pyelonephritis
PO 500mg bd
x 7-14d (7d in women)
what are the contra/precaution/preg/adr considerations for cipro?
Avoid in pregnancy, children, patient with altered
cardiac conduction
Caution in pt at risk of seizures.
ADR: tendon inflammation, hypo/hyperglycemia,
photosensitivity, QTc prologation
what are counselling points for cipro?
GI upset (take w food).
Administration apart
from Ca, Fe. CNS
(headache, dizziness),
photosensitivity. Tendon
inflammation
(discontinue at first sign
of pain, esp in elderly).
what is the dosing for nitrofurantoin in cystitis
PO 50-100mg qds x
5d
what are the contra/precaution/preg/adr considerations for nitro?
Not for pyelonephritis.
Avoid in renal impaired Crcl < 30ml/min,
pregnancy at term (38-42 weeks), G6PD def
ADR: GI, Pulmonary fibrosis (unexplained
malaise, cough, SOB). Tingling extremities
(neuropathy) with dose-accumulation.
what are counselling points for nitro?
Take with food (incr
absorption, reduce GI
upset). Nausea,
headache, dark
coloured urine.
what is the dosing for amoxiclav in cystitis
PO 625mg bd x 5-7d
what is the dosing for amoxiclav in pyelonephritis
PO 625mg tds x
10-14d
what are the contra/precaution/preg/adr considerations for amoxiclav?
Avoid in penicillin allergy, history of hepatic
impairment with Augmentin/penicillin. Generally
safe in pregnancy
ADR: cholestatic jaundice, GI esp diarrhea,
vaginal mycosis
what are counselling points for amoxiclav?
Take with/ without food.
Nausea, vomting,
diarrhoea
what is the dosing for fosfo in cystitis (uncomplicated)
PO 3g single dose
what is the dosing for fosfo in cystitis (complicated)
PO 3g eod x 3 dose
what are the contra/precaution/preg/adr considerations for fosfo?
Not for pyelonephritis; not for CrCl<30ml/min
ADR: headache, diarrhoea, vaginitis
what are counselling points for fosfo?
Take with/ without food.
Headache, diarrhoea
what are some adjunctive therapy for urinary symptoms in uti
Pain and fever – paracetamol or NSAIDs
Vomiting – rehydration
Urinary symptoms
1) Phenazopyridine (Urogesic®):
* Dose: 100-200mg tds
* an azo dye and exerts a topical analgesic effect on the urinary tract
mucosa to provide symptomatic relief
* treatment should be limited to the duration of symptoms
* Do not use in G6PD deficiency
* ADR: nausea, vomiting, orange-red discolouration of urine and stool
2) Urine alkalization: relief discomfort in mild UTI, unproven benefit
what are some non antimicrobial options for uti prevention?
1) Cranberry juice (cranberry proanthocyanidine)
* inhibits adherence of E. coli to urinary tract epithelial cells
* possibly decrease incidence of UTI
2) Intravaginal estrogen cream (remains controversial)
* decrease incidence of UTI’s in postmenopausal women
* restores vaginal flora, prevents colonization with E. coli
3) Lactobacillus probiotics
* restore normal vaginal flora and have a protective effect against E. coli colonization
* recent small controlled trial showed intravaginal lactobacillus reduced recurrence uncomplicated cystitisz`
what are some goal and monitoring parameters(step 4)
1) resolution of symptoms
- should be 24-72hrs after initiation
- if fail to respond in 2-3days/persistently positive blood/urine cultures –> need further investigation to exclude resistance, possible obstruction, renal abscess, or other disease process.
2) bacteriological clearance
- repeat culture only for pregnant women to document clearance of infection
3) no adr or allergies
is altered mental status considered a symptom of UTI?
in the absence of other urinary symptoms, altered mental status is not considered a symptom of UTI.
what are some urological procedures that involve mucosal bleeding/trauma
TURP, cytoscopy w/biopsy
which fluoroquinolone not used in UTI and why?
moxifloxacin because it does not concentrate in the urine compared to levo and ciprofloxacin.
what are the symptoms of CA-UTI
worsening or new onset fever, rigors, costovertebral tenderness, malaise, lethargy without any other cause, flank pain, hematuria, pelvic discomfort
when to initiate empiric cotrimoxazole for CA-UTI
(for women ≤65 years with CA-UTI
without upper urinary tract symptoms after an indwelling catheter has been removed)
adjunctive therapy for pain and fever in uti
paracetamol or NSAIDs
adjunctive therapy for vomiting in uti
Vomiting – rehydration
