Lecture 12

Question 1

What is the major cause of Hospital Acquired urinary tract infections?

Answer 1

Catheters

Question 2

What are the causes of community acquired urinary tract infections?

Answer 2

Prostate problems in males and the proximity effect in females

Question 3

What is the proximity effect?

Answer 3

Females have a higher incidence rates of UTIs than males as the urethra is closer to faecal origin

Question 4

What is the major pathogen causing urinary tract infections?

Answer 4

Escherichia Coli

Question 5

What are the risk factors for a urinary tract infection?

Answer 5

Sexually active women, Previous infection, Underlying disease leading to stasis of urine

Question 6

What are the key virulence factors of E.Coli?

Answer 6

Pili, Iron acquisition, Lipid A, Toxins for cell death, Intracellular bacterial comunity (strands), Quiescent intracellular reservoir

Question 7

What are the pili of E.Coli used for?

Answer 7

P-Pili are used to adhere to the kidney,
Type 1 pili are used to adhere to the bladder,
both types of pili help the microorgansim avoid getting washed away

Question 8

What is the shape of E.Coli?

Answer 8

E.coli is a gram negative rod

Question 9

What is cystisis?

Answer 9

A relatively less serious condition, but may progress up the urinary tract to cause the more serious pyelonephritis

Question 10

What is pyelonephritis?

Answer 10

Inflammation of the kidneys

Question 11

How can E.Coli be diagnosed?

Answer 11

Dipstick test, Cysteine-Lactose-Electrolyte deficient agar

Question 12

How does the dipstick test work?

Answer 12

Tests for nitrites, Leukocyte esterase, pH, Red blood cells, Protien and glucose levels

Question 13

What can be learned from the cysteine lactose electrolyte deficient agar?

Answer 13

As E.Coli is a lactose fermenter it will appear yellow, BUT Klebsiella also turns positive

Question 14

What microorganisms that cause urinary tract infections test negative for the CLED agar?

Answer 14

Pseudomonas, Proteus

Question 15

What is the purpose of the ImViC test?

Answer 15

To distinguish between E.Coli and Klebsiella

Question 16

What does the ImViC test use?

Answer 16

Indole (break down of tryptophan)
Methyl Red (fermentation of glucose)
Vogues Proskauer (Butenyl glycol production from glucose)
Citrate

Question 17

What are the ImViC test results for E.Coli?

Answer 17

Positive for Indole and methyl Red, negative for Vogues Proskauer and Citrate
(Pink, Red Light Brown, Green)

Question 18

What are the ImViC test results for Klebsiella?

Answer 18

Negative for Indole and methyl red, positive for Vogues Proskauer and Citrate
(Pale with yellow upper layer, yellow, brown precipitate, blue)

Question 19

What are the treatment options for E.Coli that do not involve antibiotics?

Answer 19

Fluids and pain relief, good hygiene practices may need to be reinforced, cranberry juice, and yoghurt can help promote the growth of good bacteria to crowd out the infection while mannose tablets may inhibit the pathogen in some cases

Question 20

When should antibiotics be considered with urinary tract infections?

Answer 20

If the disease is prolonged or progresses to more severe symptoms
This can also be identified by enumeration of more than 10^8CFU/L

Question 21

What antibiotics can be used against E.Coli?

Answer 21

Amoxicillin (Penecillin Based), Trimethoprim (Inhibits folic acid synthesis), Ciprofloxacin (inhibits DNA replication)

Question 22

What is ESBL E.Coli?

Answer 22

E.Coli that have resistance to all penicillin based antibiotics due to a beta lactamase enzyme

Question 23

How can ESBL E.Coli be treated?

Answer 23

Use of polymyxin B or E or cationic polypeptide antibiotic used as a last resort as these antibiotics can be damaging but maybe the only thing that works