Urinary Tract Infections

Question 1

What is acute cystitis?

Answer 1

infection of the bladder

Question 2

What is pyelonephritis?

Answer 2

infection of the kidney and renal pelvis

Question 3

What is sterile pyruria?

Answer 3

puss in urine without bacterial growth

Question 4

At what point does the urinary tract become sterile?

Answer 4

the bladder sphincter

Question 5

What is the most common aetiological agent of UTIs?

Answer 5

E. coli

Question 6

What is the most common gram positive cause of UTIs?

Answer 6

staph saprophyticus

Question 7

What bacteria in the same family as E. coli is a cause of UTIs?

Answer 7

proteus species

Question 8

What other bacteria cause UTIs (usually in hospitals)?

Answer 8

klebsiella, enterobacter, serratia, pseudomonas, enterococcus, staphylococcus

Question 9

Do viral pathogens cause classical UTIs?

Answer 9

no

Question 10

Which viruses shed asymptomatically in the urine?

Answer 10

CMV, rubella, polyomavirus (in immunocompromised patients)

Question 11

Which virus causes haemorrhagic cystitis?

Answer 11

adenovirus

Question 12

Which virus causes renal disease?

Answer 12

hantavirus

Question 13

How do bacteria usually access the urinary tract?

Answer 13

ascending from the urethra via contamination from the anus

Question 14

Which bacteria can infect the urinary tract from the blood?

Answer 14

staph aureus, salmonella typhi, TB

Question 15

What are the features that give the urinary tract innate immunity?

Answer 15

epithelium is resistant, some bacteria dont like growing in urine, constant flushing effect or regular bladder emptying

Question 16

Why do women get more UTIs than men?

Answer 16

because the urethra is shorter and straighter and closer to the anus

Question 17

What will increase the risk of UTIs in infant males?

Answer 17

no circumcision

Question 18

What else will increase the risk of UTIs?

Answer 18

heavily colonised distal urethra

Question 19

What abnormalities will cause an increase risk of UTIs?

Answer 19

structural abnormalities and functional abnormalities which prevent bladder emptying e.g. horse shoe kidney, tumour, stones, enlarged prostate, neurological, vesico-ureteric reflux

Question 20

What common foreign body will cause an increased risk of UTIs?

Answer 20

catheter

Question 21

What feature do most E. coli have that helps them adhere and cause UTIs?

Answer 21

type 1 fimbria

Question 22

What feature do some E. coli have that is specific for UTIs?

Answer 22

pylonephritis associated pili (PAP pili)

Question 23

Is there one specific virulence factor that all uropathogenic E. coli share?

Answer 23

no

Question 24

What enzyme does proteus have?

Answer 24

urease - to get energy from urea - ammonia as an end product

Question 25

What features helps E. coli swim up ureters?

Answer 25

flagella

Question 26

What are the symptoms of a UTI?

Answer 26

increase frequency of micturition with burning, possible fever, possible tenderness over bladder or kidneys

Question 27

If you found the pathogen of a UTI in the blood what would it indicate?

Answer 27

pylonephritis

Question 28

Why do you need to take a midstream urine sample?

Answer 28

the first part of the urine may have normal microbiota and the last part may have prostatic secretions

Question 29

What is the significance of a pathogen in a bag sample of urine?

Answer 29

no significance- may be from the urine or may be from the skin or the gut - only significant if it is sterile

Question 30

What is the significance of a pathogen in a supra pubic aspirate?

Answer 30

definitely the cause of the UTI

Question 31

Why dont you collect from the bag of the catheter?

Answer 31

because the bacteria will have replicated

Question 32

What number of white blood cells in the urine indicates infection?

Answer 32

>10^5

Question 33

Does a raised white cell count always mean infection?

Answer 33

no - could mean stones or tumours or other things - sterile pyuria

Question 34

What does the presence of squamous epithelial cells indicate?

Answer 34

a poorly collected sample

Question 35

What number of bacteria in a midstream sample indicates infection?

Answer 35

>10^5 CFU

Question 36

What does nitrites in the urine indicate?

Answer 36

there are bacteria - but not all bacteria will produced nitrites so if negative it is not definitive

Question 37

Why should you check the pH of urine before giving treatment to alkalinise urine?

Answer 37

because if the urine is alkaline there are ammonia forming bacteria (proteus) and there is a risk of forming struvite stones

Question 38

What antibiotic treatment is given for UTIs?

Answer 38

cephalexin or co-amoxyclav or trimethoprim

Question 39

What antibiotic treatment is given for sepsis caused by pyelonephritis?

Answer 39

amoxycillin and gentamicin

Question 40

When is asymptomatic bacteriuria significant?

Answer 40

in pregnancy - can be associated with premature

Question 41

What defines recurrent UTIs?

Answer 41

more than 2 in 6 months