UTI's Flashcards
List some common uropathogens
- Enterobacteriaceae (E. coli, Klebsiella spp., Proteus spp.)
- Enterococcus spp.
- CNS
- GBS
How do bacteria get into the urinary tract?
- Urethra -> Bladder -> Kidneys -> Blood
2. Bacteremia can result in seeding of the kidney
What mechanisms does the healthy human host have to eliminate microbes from the urinary tract?
- Normal flushing mechanism
- pH
- Chemical content of urine
What are some things that predispose someone to UTIs?
- Kidney stones
- Vesicourethral reflux
- Neurologic problems (DM, spinal cord injury)
- Prostate hypertrophy
- Short urethra (women)
- Urinary catheters
What is a major cause of nosocomial UTIs?
URINARY CATHETERS. Risk of UTI increases about 3% for each day of catheterization.
Guidelines for urinary catheters
- Avoid it unless necessary
- Remove it ASAP
- Hand hygiene
- Maintain drainage by gravity
- IN and OUT is better than continuous
3 basic components taken together for the Dx of a UTI
- Hx/physical
- Urinalysis
- Urine C/S
Signs and symptoms of a UTI
- Frequency of urination
- Dysuria
- Urgency
- Hesitation
- New onset of incontinence (elderly)
- Fever
- Costovertebral angle tenderness (pyelonephritis)
Malodorous or cloudy urine is a definite sign of a UTI, T or F?
FALSE
List various methods of urine collection
- Midstream
- Foley catheter
- Suprapubic aspiration
- Ileal conduit
- Nephrostomy tube
- Cystoscopy
Midstream urine collection
- Clean periurethral area prior to providing sample
- Difficult to collect from: bedridden pt’s, the elderly, infants
- Midstream urine allows for the initial stream to washout contaminating bacteria from lower urethra
Foley catheter collection
- Foley’s in for > 24 hours are probably colonized
- Try to collect from a newly inserted catheter (port)
- NEVER collect from the bag
What 2 types of patients are likely to undergo suprapubic aspiration for a urine sample?
- Pediatrics
2. Pt’s with spinal cord injuries
Urine collected from an ileal conduit is also going to grow bacteria, T or F?
TRUE
When should a urine sample be transported to the lab?
Within 2 hours to avoid overgrowth. Can refrigerate for up to 18 hours.
What 2 macroscopic variables are assessed using a urine dipstick?
- Leukocyte esterase - suggests WBCs are present
2. Nitrite - +ve if nitrate reducing bacteria are present
What can the presence of WBCs in the urine indicate?
Indicates inflammation from:
- Infection
- Cancer
- Catheters
What may the presence of RBCs in the urine indicate?
- Infection
- Kidney disease
- Renal stone
- Urinary tract cancers
- Bleeding disorders
- Contamination from menstrual blood
When is it ideal to collect urine cultures?
Before antibiotics are started
How soon might you receive the results from a urine culture?
18-24 hours. Susceptibility will come shortly after for pt’s in hospital
Quantitative urine cultures apply to what type of sample?
Midstream urine
Quantitatively, what does significant bacteremia mean?
There is > 100,000 CFU/ml (pay attention to units)
What are some factors that may influence urine culture results?
- Improper collection = contamination
- Improper storage = overgrowth
- Antibiotic Tx = decreased burden of susceptible bacteria
- Fluid intake affects quantitative results
What is required to Dx a UTI?
- Signs and symptoms present
- +ve urinalysis
- +ve urine culture
When would it be appropriate to draw blood cultures in a pt with a suspected UTI?
- Fever
- Pyelonephritis
- UTI in immunocompromised
- ALL pediatric pt’s with fever
- Sepsis
List some general principles for the Tx of a UTI
- Look at local antibiogram
- Use shortest duration possible
- Change from IV to PO, ASAP
- Reevaluate drug choice based on susceptibility report
- Remove catheter if no absolute indication
- Hydrate!
What 2 agents should no longer be used empirically for UTIs?
- Ciprofloxacin
2. TMP/SMX
What antibiotics are still good empiric choices for cystitis?
- Nitrofurantoin
- Fosfomycin
- For 1 and 2 - drug levels do not get high enough to treat pyelonephritis at the site of infection
- Amoxicillin-clavulanate
What antibiotics should be avoided for the Tx of UTI in pregnant women?
- TMP/SMX in 1st and 3rd trimester
- Nitrofurantoin > 36 weeks (hemolytic anemic in neonate)
- Quinolones
What Tx can be given for a pt that is septic from a UTI?
- IV antibiotics
2. Piperacillin-tazobactam + gentimicin
Acute cystitis
- May resolve spontaneously
- Recurrence can be common in sexually active females
- 1st episode in females -> screen for pyuria is adequate. Cultures not necessary if symptoms typical and respond to Tx
- Recurrent cystitis in men -> investigate for prostatitis, prostate hypertrophy
- Response to Tx should be seen by 48 hours
Tx for acute cystitis
- Empiric = Nitrofurantoin or fosfomycin
2. Alternatives = Cefixime OR TMP/SMX, Ciprofloxacin
Pyelonephritis
- Kidney infection
- Lower UT symptoms + fever and CVA tenderness
- Recurrence can cause loss of renal function
- May result in 2ndary bacteremia
- Lasts 7-14 days
Tx for pyelonephritis
- Not all pt’s need hospitalization
- Empiric outpatient Tx = Cefixime. Alt. = amoxicillin-clavulanate, ciprofloxacin, or TMP/SMX
- In hospital Tx = Ceftriaxone IV or Gentamicin IV
Asymptomatic bacteriurea
- Bacteria detected in urine +/- pyuria, but no symptoms
- DOES NOT require antibiotics unless pt is pregnant or undergoing cystoscopy
- This is common
Pregnancy and UTI
- Asymptomatic bacteriuria needs Tx to prevent pyelonephritis, preterm labour, and low birthweight
- Screen for bacteriuria at 12-16 weeks
- Do post-Tx cultures and monthly cultures for remainder of pregnancy
Catheter-associated UTI (CAUTI)
- Typical symptoms are absent
- Look for: fever, rigors, CVA tenderness
- In pt’s with spinal cord injury -> increased spasticity and autonomic dysreflexia
- In addition to antibiotics, change or remove catheter
- Tx for 3-14 days
