Week 3 UTIs Flashcards
(27 cards)
What is a UTI called if it is in the lower urinary tract?
Lower urinary tract -
cystitis
What is a UTI called if it in the upper urinary tract?
Upper urinary tract -
pyelonephritis
What is the difference between an uncomplicated and complicated UTI?
Uncomplicated are typical ones e.g. female, previous UTI, simple course of antibiotics
Complicated occur in patients with factors that compromise the urinary tract (cathetors, enlarged prostate, urinary obstruction, renal trnasplant) or host defence (immunocomprimised, pregnancy)
What are complicated UTIs a risk factor for?
Of note CAUTI are MOST common cause of secondary bloodstream infections
What is the most common bacterial cause of UTIs?
E. coli
What is the rule of thumb for the gram staining of bacteria?
Wet bacteria -> negative
Dry bacteria -> positive
Hint: rain is negative
What gram satinging is E.Coli?
Gram negative
What do UTI causing bacteria use to attach themselves to the walls of the urinary tract?
Pili
Regarding UTIs what does bacterial pili do?
Allows them to adhere to the urinary tract walls so they don’t get peed out
What are some bacterial viralance factors for UTIs?
What are some host defences against UTIs?
How can UTIs present differently in infants/elderly?
In infants (< 2yrs) – vomiting/fever
In elderly - less localised symptoms – confusion/falls
What cautions do you need ot take when using a urine dipstick around UTIs?
It’s very insensitive especially in older patients. ONLY TO BE USED IN PATIENTS < 65
Useful ONLY in presence of clinical UTI symptoms – presence of
nitrites (bacteria) indicate a UTI is a possible diagnosis. As low as 75% sensitivity.
An 73yo patient is drowsy and confused. Dipstick comes back positive for nitrites and hence the presence bacteria.
Do you give antibiotics?
Not necessarily.
Elderly patients can have plenty of harmless bacteria in living in their urine and the presence of bacteria doesn’t always mean an infection.
Without other UTI symptoms you might be giving the patient unnecessary antibiotics and missing the true cause of the drowsyness
What do nitrites signal in a urine dipstick?
Bacteria
What the two main methods of collecting a urine sample?
Mid stream sample
Catheter sample (from port)
In a culture samples, what is the minimum a lab can measure? What is the amount that counts as significant?
Most laboratories will only detect ≥10^4 – 10^5 CFU/mL
Generally significant if >10^5 CFU/mL
When might you treat asymptomatic bacteriuria?
Only in pregnant women
If someone has asymptomatic bacteriuria what else should you test for?
Indicator of active inflammation
specifically in urinary tract
When should you use antibiotics for cystitis?
In culture positive cases or pregnancy
In culture negative cases ibbuprofen actually works better. You should always try conservative management first.
When might you give the antibiotic nitrofurantoin?
Cystitis only.
Innefective for pyelonephritis
Why is it important to do a culture analysis before prescribing antibiotics?
A small ammount of antibiotics can mess up a culture analysis.
But you need to measure for antimicrobial resistant genes in the culture so you know what ones will work.
For community pyelonephritis what antibiotic should be used?
co-amoxiclav
ciprofloxacin
trimethorpin
For hospital pyelonephritis what antibiotic should be used?
IV Gentamicin
(With amoxicillin if sepsis severe)
