IC13 Urinary Tract Infections Flashcards
Who need to be screened and treated for asymptomatic bacteriuria?
1) Pregnant women
2) Patients undergoing urologic procedure, where mucosal bleeding is expected
How does the risk of UTI change from infants to elderly?
0-6 months
Males > Females
More structural and functional abnormalities in males
1yo - Adult
Females > Males
Females have shorter urethra
Males have additional protection of antibacterial substances secreted by prostate
Older than 65
Males = Females
Comorbidities increase risk of UTI
What is ascending UTI?
What are the risk factors? (2 pts)
Most common pathogens?
Colon or Fecal bacteria colonise urethra → Ascend to bladder and kidney
Females > Males
Use of spermicide, diaphragm contraceptive
Gut bacteria
Gram (-) enterobacteriales gut bacteria eg. E.coli, Klebs, Proteus
What is descending UTI?
Risk factor?
Caused by which pathogen?
Bacteria from distant site (eg. heart valve, bone) travel to bloodstream → bacteremia → urinary tract
Patient may already have endocarditis, osteomyelitis, other infections elsewhere
Non-gut Bacteria
Staph Aureus
Mycobacterium TB
Non pharm advice for UTI (6 points, incl after poo and sex, clothing)
Drink more water to flush out bacteria
Urinate frequently, when you feel the urge
Urinate after sex
Wipe from front to back
Wear cotton underwear, loose fitting clothing
Modify contraceptive
Who falls under uncomplicated UTI?
In healthy premenopausal, non-pregnant women, no history of abnormal urinary tract
What are the diagnosis tests needed for uncomplicated UTI?
no need any urinalysis or culture!!
Likely pathogens for Uncomplicated or Community acquired UTI
E. coli (85%)
Staph saprophyticus (5-15%)
Common coloniser
Gut gram (-) (Enterococcus faecalis, Klebs, Proteus)
First line treatment for Uncomplicated cystitis
Usually use Cotrimoxazole and nitrofurantoin
doses will be lower than pyelonephritis
PO Co-trimoxazole 800/160mg BD x 3d
PO Nitrofurantoin 50mg QD x 5d
CI in CrCl < 30 ml/min
Not in Pyelonephritis
PO Fosfomycin 3g single dose
Not used in hospitals
Reserved for ESBL producing E.coli
Not for pyelonephritis
Alternative treatment for uncomplicated cystitis
PO Beta-lactams (5-7 days)
Cefuroxime 250mg BD
Amox-Clav 625mg BD
Benefit of fluoroquinolone in UTI?
Why shouldnt use fluoroquinolones in uncomplicated cystitis? (3 points)
Concentrate well in urinary tract
Many AE
Collateral damage
Ciprofloxacin only oral agent for pseudomonas
Patient population with complicated UTI? (4 points)
Men
Children
Pregnant women
Factors that ↑ risk of getting and recurrent UTI, eg. functional, urinary tract abnormalities, genitourinary instruments, DM, immunocompromised
Diagnostic test needed for complicated UTI
UFEME
Dipstick
Urine culture
Likely pathogen in Complicated or HA-UTI (4 points)
E.coli (50%)
Enterococci
Pseudomonas (HAI)
Drug resistant strains
ESBL producing Ecoli, Proteus, Klebs
Treatment for complicated cystitis in women
Same drugs as Uncomplicated Cystitis in women
Cotrimox, Nitrofurantoin
Treat for longer duration 7-14 days
treatment for UTI in men, cystitis with no concern for prostatitis
Same as complicated cystitis
7-14 days
Treatment for UTI in men, cystitis with concern for prostatitis, pyelonephritis
PO Ciprofloxacin 500mg BD
PO Co-trimoxazole 800/160mg BD
10-14 days
How long should prostatitis be treated for?
6 weeks
Symptoms of Cystitis
More localised symptoms
Dysuria, urgency, frequency, nocturia, blood in urine (gross hematuria), suprapubic pain
Symptoms of Pyelonephritis
More systemic symptoms
Fever, rigors, headache, N/V, malaise, flank pain, renal punch, abdominal pain
What are some markers to test for UFEME? (5 points)
Which can confirm presence of UTI?
> 10 WBC /mm3 = Pyuria, inflammation
Must have pyuria to be UTI
Red Blood cells
Hematuria
Occurs frequently, nonspecific
Could be due to menses, trauma
Gram stain
Identify microbes or yeast
WBC casts
Cells or proteins formed in renal tubules
Indicate Upper UTI
Squamous Epithelial
Indicates contamination
What is tested in urine dipstick?
Nitrite
Test for gram (-) bacteria
Reduce nitrate to nitrite
Requires 10^5 bacterial per ml
False positive results can occur
Gram (+)
Pseudomonas Aeruginosa
Low urinary pH
Dilute urine
Frequent urination
Leukocyte esterase (LE)
Occurs with significant pyuria
First line treatment for Pyelonephritis (3 points)
principle: high dose, for long duration (14 days), except for fluoroquinolones cos can concentrate well in urine (7 days)
PO Fluoroquinolones
Ciprofloxacin 500mg BD x 7d
Levofloxacin 750mg OD x 5d
PO Co-trimoxazole
800/160mg BD X 14d
PO Beta lactam (10-14d)
Cefuroxime 250-500mg BD
Amox-Clav 625mg TDS
Treatment for severely ill patient who require hospitalisation with pyelonephritis (cover what)
Use aminoglycosides to cover ESBL producing strains
IV Ciprofloxacin 400mg BD + IV Gentamicin 5mg/kg
others + gentamicin
IV Cefazolin 1g TD
IV Amox-Clav 1.2g TD
Risk factor for Nosocomial / Healthcare associated UTI (3 points)
Hospitalised or Invasive urological procedures in the last 6 months
Indwelling catheter
Exposure to antibiotics
Possible pathogens in Healthcare Associated-UTI (2 points)
Pseudomonas
ESBL producing E.coli, Klebs
What to cover for HA-UTI?
Empiric treatment for HA-UTI (more sick, less sick, duration of therapy)
Pseudomonas, ESBL producing gram (-)
More sick = More broad spectrum
IV Cefepime 2g BD + IV Amikacin 15mg/kg/d
Cefepime cover pseudomonas, Amikacin cover ESBL, resistant pseudomonas
IV Imipenem 500mg QD
IV Meropenem 1g TD
Less sick = Narrow spectrum
PO Levofloxacin 750mg
PO Ciprofloxacin 500mg BD
7-14 days
How to obtain urine sample for patients with CA-UTI?
Remove old catheter, so that pathogen found will not be from biofilm but from patient
When to give antibiotics for CA-UTI?
Only when patient is symptomatic
Systematic symptoms: New onset or worsening fever, rigors, altered mental status, pelvic discomfort
Empiric treatment for CA-UTI
Duration of treatment
similar to HA-UTI for serious patients on IV
7 days for prompt resolution and deferverse in 3 days, 10-14 days for those with delayed response
What is the requirement for patient to be on PO Cotrimoxazole with CA-UTI, and no pseudomonas coverage (2 points)
Younger than 65, no upper urinary tract symptoms after catheter removed
Antibiotics contraindicated in pregnancy and why (4 points)
Ciprofloxacin
Fetal cartilage damage
Arthropathies
Cotrimoxazole (in 1st and 3rd trimester)
1st trimester: Folate deficiency
3rd trimester: Kernicterus
G6PD deficiency
Nitrofurantoin (at term, 38 week onwards)
Cotrimox
Aminoglycosides
What should we give to pregnant patients
beta lactams eg. Cefuroxime, Amoxicillin clavulanate
treat for 7 days for ASB and cystitis, 14 days for pyelonephritis
How long should symptoms resolve
1-3 days
Trace blood and urine cultures, streamline according to AST
Repeat culture for pregnant women
Diagnosis of Pyuria
> 10 WBC /mm3 during EFEME analysis
Dipstick should show (+) Leukocyte esterase also
