Microbiology of UTIs

Question 1

Define UTI.

Answer 1

Presence of microorgansims in the urinary tract that are causing clinical infection

Question 2

Define lower UTI.

Answer 2

Infection of the bladder

Cystitis

Question 3

Define upper UTI.

Answer 3

Infection involving the ureters +/- the kidneys

pyelonephritis

Question 4

Define complicated UTI.

Answer 4

UTI ccimplicated by systemic sepsis or urinary structura abnormalities or stones.
Requires a longer course of antibiotics

Question 5

What is bacteriruria?

Answer 5

Bacteria in the urine

Question 6

Who is predisposed to UTI?

Answer 6

Female (short wide urethra, proximity of anus to urethra)
Catheterised patient
Abnormality of the urinary tract (congenital posterior urtheral valves, double ureter, horseshoe kidney etc)
Post general anaesthetic
Rena calculi

Question 7

What are the 2 routes of infection of a UTI?

Answer 7

Ascending infection

From the bloodstream

Question 8

What organisms may cause UTI?

Answer 8

E. coli 
Klebsiella sp. 
Enterobacter sp. 
Proteus sp.
Staphylococcus saphrophyticus 
Staphlococcus aureus - uncommon 
Pseudomonas aeruginosa

Question 9

A UTI caused by proteus causes what and is associated with what?

Answer 9

Causes foul smelling urine

Assocciated with stone formation

Question 10

What 2 species of Enterobacter cause UTI? Which one is harder to eradicate?

Answer 10

Enterococcus faecalis

Enterococcus faecium - more resistant to AB so harder to treat

Question 11

A UTI caused by Staphylococcus saphrophyticus usually affects what group of people?

Answer 11

Women of child bearing age

Question 12

A UTI caused by Pseudomonas aeruginosa is associated with what commonly?

Answer 12

Catheters

UT instrumentation

Question 13

Which AB would be use to treat a UTI caused by Pseudomonas aeruginosa?

Answer 13

Ciprofloxacin

Question 14

What are the symptoms and signs of a UTI?

Answer 14

Dysuria 
Increased frequency 
Nocturia 
Haematuria 
Fever 
Loin pain - groin pain 
Rigours 
Vomiting

Question 15

What is the ideal urine specimen?

Answer 15

Mid-stream specimen of urine (MSSU)

Question 16

Which container should be used for urine samples?

Answer 16

Boricon container (red top) 
Contain boric acid which is a preservative

Question 17

A genuine UTI in a non-catheterised patient will usually e caused by how many organisms?

Answer 17

1

Question 18

What does ESBL stand for?

Answer 18

Extended spectrum beta-lactamase

Question 19

If a bacteria produced ESBL then how does this change the management?

Answer 19

Bacteria is resistant to all cepahlosporins and almost all penicillins

Question 20

What AB may be used for ESBL producing bacteria?

Answer 20

Ntrofurantoin
Pivemcillinam
Temocillin
Meropenem

Question 21

What is considered the last choice AB?

Answer 21

Meropenem

Question 22

A carbopenemase-producing enterobacteriacae is resistant to what antibiotic?

Answer 22

Meropenem

Question 23

What is the empirical AB treatment for a female lower UTI?

Answer 23

Trimethoprim or Nitrofurantoin orally

3 days

Question 24

What is the empirical AB treatment for a male lower UTI?

Answer 24

Trimethoprim or Nitrofurantoin orally

7 days

Question 25

What is the empirical AB treatment for a complicated UTI or pyelonephritis in the GP?

Answer 25

Co-amoxiclav or co-trimoxazole | 14 days

Question 26

What is the empirical AB treatment for a complicated UTI or pyelonephritis in the hospital?

Answer 26

Amoxicillin and Gentamicin IV | 3 days

Question 27

What is the empirical AB treatment for a complicated UTI or pyelonephritis in the hospital in a penicillin allergic patient?

Answer 27

Co-trimoxazole and gentamicin IV | 3 days

Question 28

What is asymptomatic bacteriuria? Does it require antibiotics?

Answer 28

Significant bacteriuria >10tothe5 orgs/mL Pateint is asymptomatic NO AB given

Question 29

If asymptomatic bacteriuria occursin pregnancy are AB given?

Answer 29

Yes

Question 30

If aysmptomatic bacteriuria in pregancy is not treated what may occur?

Answer 30

20-30% progress to pyelonephritis | May lead to intra-uterine growth retardation or premature labour

Question 31

When should AB be given in a UTI of a catheterised pateint? Why?

Answer 31

If they are symptomatic | Giving unnecessary AB results in more resistant organisms colonising the catheter

Question 32

What can cause abacterial cystitis?

Answer 32

Early phase of UTI Urethral trauma ("honeymoon cyctitis") Urethritis caused by chlamydia, gonorrhoea

Question 33

What maya help in abacterial cystitis?

Answer 33

Alkalanising the urine with sodium bicarbonate