Urinary Tract Infection Flashcards
Describe the bacterial etiology of UTI.
E coli = most common d/t NOT:
- wiping front to back
- using condoms
- washing after sex
S saprophyticus:
- women with STI’s
Proteus = suspect kidney stone
Klebsiella:
- catheter
- polymicrobial
Describe the non-bacterial pathogenesis/etiology of UTI.
- Intercourse
- Inadequate hydration
- Voiding infrequently (< q 2-3 hours)
What are the guidelines for screening/treating asymptomatic bacteriuria?
Screen & Treat:
- ALL pregnant women with antibiotics x 4 - 7 days
(to prevent pre-term labor)
Do NOT treat:
- children
- older adults
- diabetics
- transplant recipients (especially kidney)
- spinal cord injury
- indwelling catheter
How is uncomplicated UTI classified?
Uncomplicated UTI:
- Cystitis/bladder infection/UTI
- Low patient risk
- NO systemic symptoms
How is complicated UTI classified?
Complicated UTI:
- Kidney involvement (lower or upper)
- High risk patients:
- older age
- pregnancy
- pediatric patients
- Systemic symptoms:
- fever
- malaise, etc.
What are the key signs/symptoms of uncomplicated UTI?
Triad of symptoms:
- dysuria
- urgency
- frequency
What are signs/symptoms of uncomplicated UTI other than the key triad?
- Incomplete emptying sensation
- Suprapubic pain
- Back pain
- Gross hematuria (may also be micro hematuria)
- Foul-smelling urine (if proteus bacteria, suspect stones)
- Scant voiding
If a UTI is suspected, what diagnostic studies should be ordered?
- Urinalysis
- Urine culture ONLY if:
- recurrent infection (clears and returns)
- refractory infection (never clears)
- high risk patients:
- children
- men
- pregnant women
- older adults
What results indicate a positive urine culture?
- Midstream > 100,000 organisms
- Catheter > 1,000 organisms
What urinalysis results indicate infection?
Nitrites = Gram negative bacterial infection
WBC’s = infection
WBC casts = pyelonephritis
Leukocyte esterase: usually = infection
2/3 of the following = infection:
- blood
- nitrites
- leukocytes
Discuss the role of nitrates and nitrites in urinalysis for UTI.
Nitrates:
- normal in urine
- converted to nitrites by gram negative bacteria
Nitrites = gram negative infection
- sensitivity: only 50% d/t only indicates gram negative infection
- specificity: high
Discuss the role of WBC’s/pyuria in urinalysis for UTI.
WBC’s = infection
- most reliable indicator of infection (95% sensitivity)
*WBC casts = pyelonephritis
Discuss the role of leukocyte esterase in urinalysis for UTI.
Leukocyte esterase:
- enzyme produced by WBC’s
- specificity = 60% - 90%
- usually indicates UTI
What is the first-line antibiotic treatment for uncomplicated UTI?
Nitrofurantoin/Macrobid:
- avoid if pyelonephritis suspected
- avoid in 1st trimester of pregnancy
Duration: 3 - 6 days
What are appropriate antibiotics for uncomplicated UTI?
- Nitrofurantoin = FIRST LINE!
- Bactrim
- Cephalosporins
- Ciprofloxacin/Levofloxacin
Avoid any antibiotic taken in the past 3 months!
What is important to remember about Bactrim in conjunction with UTI?
Bactrim:
- mostly inappropriate d/t E. coli resistance > 20% in most US states
- do NOT use for patients < 2 months old
Which groups of patients should receive cephalosporins for uncomplicated UTI and why?
Reserve for use with:
- children
- pregnant women
Why?
- Due to high rates of resistance with E. coli.
Discuss the use of ciprofloxacin/levofloxacin with uncomplicated UTI.
- Low rates of resistance with E. coli but NOT FIRST LINE!
- Cautioned use with QT prolongation
- Not for use with:
- <18 years old
- pregnancy
What medications (other than antibiotics) should be considered for patients with uncomplicated UTI and why?
Antispasmotics: Why?
- Phenazopyridine (pyridium) - for dysuria
- Flavoxate (urispas) - has antiseptic properties
- ** Turns urine orange
Local estrogen - Who?/Why?
- if postmenopausal
- reduces UTI risk d/t E2 receptors in urethra
What instructions (non-pharmaceutical-related) should be given to patients with uncomplicated UTI?
- Treat UTI promptly
- Hydrate with 8 glasses (8 oz each) of water daily
- Avoid bladder irritants:
- caffeine
- alcohol
- carbonated drinks
- fruit juice
- Sexual intercourse:
- avoid during treatment
- void afterward
- use lubrication
- Follow up within 1 month if blood is present on diagnosis
List common features of complicated UTI.
- Can be lower or upper UTI
- Symptomatic or asymptomatic
- Asymptomatic bacteriuria in pregnancy
- Comorbid conditions (DM, immunocompromised, etc.)
- Structural, functional, metabolic, or catheter
- Multi-drug resistance
- Greater risk for sepsis, bacteremia, or death
- Special groups:
- older adults
- pregnancy
- men
- children
What are common signs and symptoms of complicated UTI?
S/S of uncomplicated UTI, especially:
- dysuria
- urgency
- frequency
Systemic S/S:
- fever
- chills
- rigors
- marked fatigue or malaise
What signs and symptoms might be expected in older adults with complicated UTI?
- Fever
- Fatigue
- Falls
- Mental status changes
- Hematuria
- Anorexia
- Nausea/vomiting
- Sepsis
- New or worsening urinary incontinence
Describe treatment duration for complicated UTI.
7 - 14 days for:
- children
- pregnant women
- diabetic patients
- older adults
10 - 14 days for:
- men* d/t complex anatomy
(rare < 50 years old)
*Note: get culture for urine and STD
What assessment findings and diagnostic tests might indicate upper UTI/complicated UTI vs lower UTI/uncomplicated UTI?
Assessment:
- CVA tenderness
U/A:
- WBC casts indicate pyelonephritis
- Blood: if + (or if patient very ill) => REFER (note: get culture with sensitivity before Rx)
CBC:
- Leukocytosis
Sed Rate (ESR)/CRP:
- Positive indicates inflammation => Upper UTI
Discuss the significance of the following casts when found in urinalysis:
Hyaline
Crystals
RBC
WBC
Epithelial
Hyaline:
- most common
- Causes:
- low urine low
- dehydration
- vigorous exercise
Crystals: No clinical significance
RBC:
- ALWAYS pathological => REFER!!!
- Causes:
- possible glomerulonephritis
- lupus
- urinary tract injury
WBC:
- REFER!!!
- Causes:
- inflammation
- infection
- pyelonephritis (not UTI)
Epithelial:
- Causes:
- acute nephrosis
- hepatitis
