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Flashcards in UTI Deck (21):
1

What is the most common infecting organism in acute infection?

E. coli, 95% of UTI are caused by single bacterial species
O1,O2,O4,O6,O7, O8,O75,O150, O18ab

2

What other for organisms are responsible for UTI?

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

3

What are the antibacterial host defences?

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

4

Where do the organisms for UTI come from?

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

5

Where do the bacteria go once in the bladder?

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

6

How does obstruction affect susceptibility to UTI?

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

7

How can neurological problems affect obstruction?

Poliomyelitis, tabes dorsalis, diabetic nephropathy, spinal cord injuries

8

What is the haematogenous route?

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

9

What are upper UTI symptoms?

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

10

How can UTI present in older patients?

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

11

What the ix for UTI?

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

12

What does a complicated UTI refer to?

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

13

How do you interpret culture?

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

14

What are the methods of sampling?

Msu, Catheterisation, supra public aspiration

15

What is sterile pyuria due to?

Prior abx
Calculi
Catherisstion
Bladder neoplasm
TB
STI

16

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

Greater than 30 colonies. 10 to the 5 colony forming units.
Sterile less than 10 to 4

17

How is nitrofurantoin effective?

Urinary antiseptic, broad spectrum
Doesn't have systemic absorption, so take after you've gone to the loo so fresh urine has abx

18

What is recommend in urosepsis?

Aminoglycosides

19

What causes fungal infection?

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

20

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

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

21

What are the complications of upper uti?

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