Microbiology of the Urinary Tract

Question 1

What is Cystitis?

Answer 1

A bladder infection

Question 2

What is Pyelonephritis?

Answer 2

A kidney infection

Question 3

What are the two routes of acquisition for a UTI?

Answer 3

Ascending

Haematogenous

Question 4

Give two examples of lower UTIs

Answer 4

Cystitis

Urethritis

Question 5

What is a nosocomial infection also known as?

Answer 5

Hospital acquired infection

Question 6

What is the most commonest bacteria which causes UTIs?

Answer 6

Escherichia coli

Question 7

Aside from E.Coli, state other common bacteria which cause UTIs

Answer 7

Coagulase-negative staphyloccoci
Proteus mirabilis
Candida
Kiebsella
Enterobacter

Question 8

Which virus is associated with hemorrhagic cystitis?

Answer 8

Adenovirus

Question 9

State 3 viruses which cause UTI

Answer 9

Adenovirus
BK virus
JC virus

Question 10

State 4 host defences against UTIs

Answer 10

1. Urine flow / micturition
2. Urine chemistry
3. Secretory factors i.e. IgA / Lactoferrin
4. Mucosal defences i.e. GAGs

Question 11

Why are females more likely to acquire UTIs than males? 3 reasons

Answer 11

1. Shorter urethra
2. Urethra opens to introitus
3. Anus closer to urethra

Question 12

Why are anatomical abnormalities i.e. congenital / diverticula etc a risk factor factor UTIs?

Answer 12

Risk of urine reflux, stagnant urine or residual urine after incomplete emptying

Question 13

Why is catheterisation a risk factor for UTIs? 3 reasons

Answer 13

• Catheters bypass host defences
• Are a foreign body
• Lead to biofilm formation

Question 14

Why is pregnancy a risk factor for UTIs? 3 reasons

Answer 14

• Dilation of ureters
• Incomplete bladder emptying
• Gestational glycosuria

Question 15

Why are foreign bodies such as stones a risk factor for UTI? 2 reasons

Answer 15

• Mucosal damage

- Host defences are less accessible to bacteria

Question 16

What symptoms could one expect to see in patients with Cystitis?

What about elderly patients?

Answer 16

• Polyuria / dysuria / urgency / fever / suprapubic discomfort

In elderly:

• Patient may be asymptomatic
• Sudden onset of confusion

Question 17

What symptoms could one expect to see in infants?

Answer 17

• Failure to thrive

- Poor feeding

Question 18

What symptoms could one expect to see in patients with Pyelonephritis?

Answer 18

• Symptoms of cystitis
• Loin pain
• Fever
• Rigors
• Renal angle tenderness

Question 19

What is likelihood of bacteruria with catheter use?

Answer 19

5-10% increase with each day catheter is used

Question 20

How can doctors prevent catheter-associated UTIs? 5 examples

Answer 20

1. Do not catheter if unnecessary
2. Limit duration of catheter
3. Aspect insertion
4. Closed drainage system
5. Ag++ bonded catheter use

Question 21

Give 4 examples of anti-microbials to be used for management of an uncomplicated UTI

Answer 21

1. Trimethoprim
2. Nitrofurantoin
3. Ampicillin / Amoxicillin
4. Quinolones