UTI

Question 1

What is the most common infecting organism in acute infection?

Answer 1

E. coli, 95% of UTI are caused by single bacterial species

O1,O2,O4,O6,O7, O8,O75,O150, O18ab

Question 2

What other for organisms are responsible for UTI?

Answer 2

Proteus mirabilis -renal stones
Klebsiella aerogenes
Enterococcus faecalis 
Staph sapro- virulence factors, common in young women 
Staph epi

Question 3

What are the antibacterial host defences?

Answer 3

Urine - osmality, ph, organic acids
Urine flow and micturtion
Urinary tract mucosa- bacteriacidal activity, cytokines

Question 4

Where do the organisms for UTI come from?

Answer 4

Contamination from perianal and vulvar area- vaginal introitus, periturethal area

Question 5

Where do the bacteria go once in the bladder?

Answer 5

Ureter, then to renal pelvis and parenchyma, especially with reflux

Question 6

How does obstruction affect susceptibility to UTI?

Answer 6

Mechanical
Extra renal- valves, stenosis, bands, calculi, extrinsic urethral compression, bph
Intra renal- nephrocalconis, uric acid nephropathy, analgesic nephropathy, PKD, hypokalaemic nephropathy,

Question 7

How can neurological problems affect obstruction?

Answer 7

Poliomyelitis, tabes dorsalis, diabetic nephropathy, spinal cord injuries

Question 8

What is the haematogenous route?

Answer 8

Haematologist- kidney frequently site of abcesses in patients with s aureus bacteraeima or endocarditis
Rarely gram neg

Question 9

What are upper UTI symptoms?

Answer 9

Fever, rigors (gram neg)
Flank pain
Luts before upper occasionally

Question 10

How can UTI present in older patients?

Answer 10

Asymptomatic, not diagnostic, atypical, eg abdo pain and change in mental status

Question 11

What the ix for UTI?

Answer 11

Dipstick, msu for microscopy, culture, sensitivities
Bloods for upper
Renal uss
Intravenous urography

Question 12

What does a complicated UTI refer to?

Answer 12

Infection with functional or structural abnormalities including indwelling catheter and calculi
Men, pregnant women, children, patients. Treat asymptomatic pregnant women.

Question 13

How do you interpret culture?

Answer 13

White blood cells- more than 10^4, inflammation. Absent in childhood
Sterile pyuria- chlamydia, vaginal infection, renal pathology

Question 14

What are the methods of sampling?

Answer 14

Msu, Catheterisation, supra public aspiration

Question 15

What is sterile pyuria due to?

Answer 15

Prior abx 
Calculi 
Catherisstion 
Bladder neoplasm 
TB
STI

Question 16

What is the cut off for bacteria in culture for infection?

Answer 16

Greater than 30 colonies. 10 to the 5 colony forming units.

Sterile less than 10 to 4

Question 17

How is nitrofurantoin effective?

Answer 17

Urinary antiseptic, broad spectrum

Doesn’t have systemic absorption, so take after you’ve gone to the loo so fresh urine has abx

Question 18

What is recommend in urosepsis?

Answer 18

Aminoglycosides

Question 19

What causes fungal infection?

Answer 19

Candida, indwelling catheter, abx can affect normal flora. Treat for thrush
Remove catheter
Immunocompromised- treat

Question 20

What part of the kidney is more likely to be infected?

Answer 20

Few needed to infect the medulla, 10000 times more needed for cortex
Sepsis, septicaemia, aggressive tx, broad spectrum
Give co amox and or gentamicin
Imaging

Question 21

What are the complications of upper uti?

Answer 21

Perinephric abcess
Chronic pyelonephritis, scarring and renal impairment
Septic shock
Acute papillary necrosis