UTIs Flashcards
Is the threshold for indicating an infection lower or higher in catheter sample?
Lower (>10^2)
Are recurrent UTIs in women caused by relapse or reinfections most commonly?
Reinfections
Which bacteria can cause UTIs via haematogenous spread?
Staph aureus
TB
Salmonella Typhi
What is the problem with females having short urethras?
Shorter distance for bac to travel to infected
Opening is closer to the anus
How does sexual intercourse predispose one to a UTI?
Bac are pushed up the urethra
Type I fimbriae are important because…
Most host cells have receptors for them
What concentration of bac in the urine suggests an infection?
>10^5/ml CFU
Where are commensal bacteria expected to be found in the UT?
Below the spincter of the bladder
What is asymptomatic bacteriuria?
Bacteria in the urine without symptoms
What antibiotics do you use for UTIs?
Co-amoxyclav
Cephalexin
Trimethoprin
Which virus causes haemorrhagic cystitis?
Adenovirus
When does the bladder usually hold *Salmonella *Typhi asymptomatically?
When there is unlying damage eg by after Schistomiasis
What result from a bag sample is significant?
Sterile: no UTI
T/F Rised WBC in urine means infection.
False could be stones or tumours as well
What is the most likely *Staph *species to cause UTIs?
saprophyticus
What are some innate defences of the bladder?
Urine flushing
Bac don’t like to grow in urine
Epithelium is hard to colonise
Transitional epithelium resists colonisation
Which viruses are sometime shed in urine?
CMV
Rubella
Polyomaviruses
What is sterile pyuria?
Pus in the urine without bacteria
What are the symptoms of UTIs?
Burning on urination
Fever
Chills
Tenderness to palpation
Why alkalinise urine in UTIs?
Prevent acidification caused by bac
What is the vesico-ureteric reflux?
When contraction of the bladder pushes urine up the ureters
Which has greater affinity for Fe transferrin or siderophore?
Siderophore
When does not being circumcised cause more UTIs?
In boys
What does bacteraemia in UTIs indicate?
Pyelonephritis
Which bacteria uses urease?
Proteus
When is asymptomatic bacteriuria bad?
In pregnant women
Which organ does Salmonella Typhi inhabit in carriers?
The gall bladder
What result from a suprapubic aspirate is significant?
Any bacteria as bladder should be sterile
What can cause sterile pyuria?
Non-infectious condition
Partial treatment
Difficult to growth bacteria (eg TB)
What is an infection of the kidneys called?
Pyelonephritis
What is a siderophore?
Complex bacteria produce to acquire Fe
What is haemolysin?
A bacterial toxin that breaks down RBCs
What should you do when one gets pyeonephritis?
Check for anatomical abnormality
What are the 4 type of urine sampling techniques?
MSU
Bag sample
Catheter sample
Suprapubic aspirate
What is the most common aetological cause of community acquired of UTIs?
E. coli
What level of WBCs in the urine is significant?
>10^5/ml
How often do sexually active women get UTIs?
Once every two years
How do you confirm a UTI when a patients CFU is borderline?
Take multiple samples
What clinical syndromes can viral UTIs caused?
Usually asymptomatic shedding however
Rarely: Haemorrhagic cystitis
Renal disease
How many squamous cells are there in a normal urine sample?
None, having them indicates a poorly collected sample
Which are more suspectible to relapse, men or women?
Men
What can recurrent UTIs in women mean?
Genetic predisposition
Anatomical abnormality
Intercourse, spermicide, incontinence
Why use a bag sample for babies?
Don’t want to catheterise as might introduce microbes
Can’t take a MSU sample with babies
How do you collect a sample from a catheter?
Directly from stream in the collecting tube - not from the bag!
What is an infection of the bladder called?
Cystitis
