12 - UTI Flashcards
What is the most common pathogen in acute cystitis ?
E. coli >80%
What are some other less likely pathogens?
Staphylococcus saprophiticus
Klebsiella spp
Proteus mirabilis
What are some urinary tract defences?
- low pH
- osmolality
- urea
- organic acids
- epithelial glycosaminoglycin
- immunoglobulins
What are the risk factors for acute cystitis ?
- female - previous UTIs, sexually active (condom or spermicide use), pregnancy, post-menopausal
- obstruction (benign prostatic hyperplasia), urinary reflux, incontinence, urinary catheter
- diabetes, immunocompromised
What are the typical clinical signs and symptoms of a UTI in the elderly?
- Dysuria (pain), frequency, urgency (90% probability with 2 out of 3*), hematuria
- without fever or flank pain, vaginal discharge, or new sexual partner
- Atypical presentation in elderly such as confusion, GI symptoms, loss of appetite
Sensitivity
- positive when disease present
- low false negatives
SNOUT
-negative test rules it out
Specificity
- negative when absent
- low false positives
SPIN
-positive test rules it in
What is 1st line for mild-moderate cystitis (UTI) ?
2 options for 1st line
- Nitrofurantoin (MacroBID) for 5 days
- TMP-SMX for 3 days
Is nitrofurantoin effective against systemic infections such as kidney infection?
NO - it concentrates in the urine, not effective against pyelonephritis
Side effects of nitrofurantoin?
Rare but serious adverse effects:
-hematological, pulmonary and hepatic toxicity (especially elderly, those with renal dysfunction or prolonged use)
Nitrofurantoin:
Not recommended if CrCl < _____
30 mL/min
Nitrofurantoin:
Ok in pregnancy?
CI in pregnancy women at term > 36 weeks
Nitrofurantoin:
Ok in kids?
CI in neonates < 1 month old
Who else is Nitrofurantoin CI in?
G6PD deficiency (hemolytic anemia)
Nitrofurantoin:
____% clinical efficacy
80-90%
TMP-SMX:
-Increasing resistance in _____
E. coli
TMP-SMX:
Has high rate of potentially serious adverse effects including ?
particularly rashes and hypersensitivities
TMP-SMX:
not recommended if CrCl < ____
10-15 mL/min
TMP-SMX:
Ok in pregnancy?
NO
TMP-SMX:
Who else is it CI in?
G6PD deficiency (hemolytic anemia)
TMP-SMX:
_____% clinical and bacterial efficacy, 10% lower with single dose (well studied)
90%
List 3 alternatives for UTI
1) Amox-clav 875/125 q12h x 7 days
2) Cephalexin 500 mg q6h x 7 days
3) Fosfomycin tromethamine 3 g x 1 dose
Why does amox-clav or cephalexin need 7 days to work instead of 3 or 5 like the previous agents?
B-lactams need at least 7 days to work for a UTI bc they don’t work as fast in the urine (takes a longer period of time)
Describe Fosfomycin Tromethamine 3 g x 1 dose
- phosphoric acid derivative, inhibits early peptidoglycan synthesis
- mild-moderate cystitis associated with E. coli or E. faecalis
- rare resistance and collateral resistance
- similar clinical efficacy, potentially lower bacterial efficacy than comparators (can be more relapses)
- higher cost (about $35)
What is saved for reserve use?
Flouroquinolones (excluding Moxi) x 3 days
-all at low dose (on the chart !)
Fluoroquinolones are saved for what type of infections?
moderate-severe or complicated infections including pyelonephritis or suspected resistance
Flouroquinolones:
___% clinical and bacterial efficacy
> 90%
Flouroquinolones:
Who is it CI in?
- pregnancy
- children
What are the options for treating UTI in pregnant women?
3
1) Nitrofurantoin x 7 days
2) Amox-clav x 7 days
3) Cephalexin [Cefixime] x 7 days
UTI in pregnancy:
When is nitrofurantoin not recommended?
> 36 weeks
UTI in pregnancy:
When is TMP-SMX not recommended?
in 1st and 3rd trimesters
*just to be safe, prob wouldn’t ever recommend this in pregnancy
UTI in children:
Incidence 2-8% by __ years of age
7
UTI in children:
more common in _____
females (4x)
UTI in children:
How are they diagnosed ?
- urine culture (80% E. coli) and confirm treatment success with follow-up culture
- work-up for pyelonephritis, underlying medical condition or anatomical abnormality (vesicoureteral reflux)
What are the 4 options for treating a UTI in children?
- Amox-clav
- Cephalexin [Cefixime]
- Nitrofurantoin
- TMP-SMX
-Gent +/- Amp/ Ceftriaxone (iv and for pyelonephritis)
What makes children more susceptible to UTI ?
the anatomy of ureters and urinary tract - they should grow out of it
What is the essential patient counselling information for acute uncomplicated cystitis ?
-Adherence, analgesics for symptom relief, follow-up if symptoms exceed 2-3 days or relapse
What is the role of cranberry juice?
- active compounds such as proanthocyanidins inhibit bacterial adherence to uroepithelium
- significant variability among products (juices, tablets, capsules)
- not effective for treating infection, and limited data for preventing recurrences
- NOT FOR TREATMENT
- may be beneficial for prevention
Define a Relapse
Initial organism within 2 weeks
How do we treat a Relapse ?
- Urine culture to identify potentially resistant pathogen and work-up for pyelonephritis
- Re-treat, consider longer duration x 10-14 days
Define a Recurrence
2 infections within 6 months of > 3 infections within 12 months
How do we treat a Recurrence ?
- Treat as described for acute uncomplicated cystitis
- For frequent recurrences, urine culture and work-up for underlying medical conditions
What are approaches to managing frequent recurrences ?
1) Prophylaxis post-coital or continuous with Nitrofurantoin 50mg or 100mg HS, TMP-SMX 40/200mg HS 3 times/week or TMP 100 mg HS
* increasing resistance with continuous prophylaxis
2) patient-intitiated antimicrobial therapy for symptoms, providing urine sample
3) topical estrogen for post-menopausal women
(as estrogen decreases, the incidence of UTI’s increase)
What is the #1 risk factor for pyelonephritis ?
leaving an untreated, symptomatic UTI
Why do we always treat pregnant women with bacteriuria even if asymptomatic ?
Even asymptomatic bacteria in urine can have detrimental effects on fetus and mom (lower birth rates and premature births). At time of delivering, if there is bacteria present, it can spread and cause infection elsewhere.
Duration of treatment for asymptomatic bacteriuria in pregnancy ?
3 - 7 days
Who is antimicrobial therapy not indicated for asymptomatic bacteriuria?
- diabetics
- advanced age
- nursing home residency
- spinal cord injury
- urinary catheter
What is the relevance of catheter-associated UTI ?
- Bacteriuria rate of 3-10% in catheterization, 10-25% develop UTI
- Often polymicrobial involving atypical and MDR organisms
- Signs of infection are the same (fever, pyuria, flank pain, catheter obstruction, new-onset confusion)
- Remove or replace catheter, and antimicrobial therapy x > 7 days as per culture/susceptibilities
____ days is usually limit for a urinary catheter before it needs to be changed
7-10
A male UTI is automatically considered _______
complicated
What other factors make a UTI complicated?
- male
- lesions
- obstructions or neurological/muscular disease
- diabetes
- immunocompromised
What are the most common pathogens in acute pyelonephritis ?
- E. coli (>75%)
- P. mirabilis (urinary stones)
- S. aura s(hematogenous)
- Enterococcus (HCA, catheter-associated)
What are the risk factors for acute pyelonephritis?
- acute uncomplicated cystitis (UTI), previous pyelonephritis
- elderly, pregnancy, diabetes, immunocompromised
- anatomical abnormalities, lesions or obstruction or neurological/muscular disease
Clinical signs of pyelonephritis ?
Fever > 38.3 Chills Leukocytosis Flank Back and/or abdominal pain GI symptoms
What factors constitute complicated pyelonephritis ?
- children, pregnant women (and those listed for complicated cystitis)
- urosepsis with significant systemic signs of infection
What is the treatment for mild-moderate pyelonephritis?
Cipro HD x 7 days
Levo mid dose x 7 days or HD x 5 days
*doses are higher bc we need to get systemic levels
Alternatives for the treatment for mild-moderate pyelonephritis?
(2)
- TMP/SMX x 14 days
- Amox-clav x 14 days
What is the treatment for moderate-severe pyelonephritis?
Cipro 400mg q12h
Levo HD x 7-14 days
What are the options for severe or hospital-acquired pyelonephritis (IV) ?
- Gent +/- Ampicillin (enterococcal coverage)
- Ceftriaxone
- Pip-tazo
- Meropenem/Ertapenem
Expected response for treating pyelonephritis?
clinical improvement within 1-2 days and resolution within 3 days
Read the case on page 8
okay
What is acute prostatitis ?
- sudden onset fever, tenderness and urinary symptoms
- good response to antimicrobial treatment
- Cipro/Levo or TMP-SMX as per culture/susceptibilities x 4 weeks, severe infection may require initial iv therapy, confirm treatment success with follow-up culture
What is chronic prosthesis ?
- complication of recurrent infections
- urinary symptoms including lower back pain or pressure
- poor treatment response due to low antimicrobial penetration into prostatic fluid
- Cipro/Levo x >4-6 weeks as per culture/susceptibilities, may also require chronic suppressive therapy or surgery