L22-Urinary tract infection [2013.09.11]

Question 1

What are the potential consequences of UTI?

Answer 1

Chronic renal failure, bacteremia and urinary stones

Question 2

What are the host defense against UTI?

Answer 2

*** flushing effect of urine
Humoral immunity
Cell mediated immunity

Question 3

What are the virulence factors of UTI?

Answer 3

Lipopolysaccharide capsular
Polysaccharide
Toxins : (1)hemolysin (2)aerobactin protease

Question 4

What are the usual bacteria involved in UTI?

Answer 4

E.coli, group B streptococcus, enterococcus

Most caused by enteric or skin bacteria

Question 5

What are the host factors that cause UTI?

Answer 5

Length of the urethra 
Mechanical factors:
(1)sexual intercourse
(2)trauma
(3)contraceptive diaphragm 
(4)catheter
Density of bacterial receptors 
Hormonal effect on mucosa 
Underlying disease

Question 6

What is the pathway of spreading of UTI?

Answer 6

Bladder -> Kidney -> Blood

Question 7

What is the cause of urinary reflux?

Answer 7

Incompetent of ureterovesical valves

Question 8

What is the cause of poor emptying?

Answer 8

Neurogenic bladder

Question 9

What is the cause of dilation and decreased peristalsis of ureter

Answer 9

Pregnancy

Question 10

What is the cause of obstruction

Answer 10

Stones

Question 11

What is the cause of immune incompetence?

Answer 11

Diabetes mellitus

Question 12

What is the cause of nidus of persistence?

Answer 12

Catheter

Question 13

What kind of damage will polysaccharide bring?

Answer 13

Inhibit phagocytosis

Question 14

What kind of damage will lipopolysaccharide bring?

Answer 14

Inflammation

Question 15

What kind of damage will hemolysin of E. coli bring?

Answer 15

Tissue damage

Question 16

What kind of damage will urease bring?

Answer 16

Stone formation

Question 17

Give an account to uncomplicated UTI

Answer 17

Without structural abonomality

E. coli (80%) or S saprophyticus

Question 18

Give an account to complicated UTI

Answer 18

With structural abnormalities
High likelihood of complications
Klebsiella, enterobacter, pseudomonas, Serratia

Question 19

What is the most common uropathogen causing UTI in patient aged between 15 and 50 years old?

Answer 19

E. coli (72%)

Question 20

What is the most common uropathogen causing UTI in patietn aged above 50 years old?

Answer 20

E. coli (53%)
Klebsiella (12%)
Enterococcus (12%)

Question 21

What are the symdromes of UTI?

Answer 21

Acute pyelonephritis 
Perinephric abscess 
Cystitis 
Asymptomatic bacteriuria 
Prostatitis

Question 22

What are the criteria in diagnosing UTI?

Answer 22

Both pyuria (WBC in urine) and 
bacteriuria

Question 23

What are the other microbiological tests that we could carry out to diagnose UTI?

Answer 23

Esterase

Nitrite detection

Question 24

What are the possible errors in using esterase as an indicator?

Answer 24

Some drugs may lead to false positve results

Positive results may occur from contamination of specimen by vaginal discharge

Question 25

What are the possible errors in using Nitrite detection?

Answer 25

Negative test may not rule out UTI - Some bacteria do not have that enzyme - may not retain in the baldder long enough

Question 26

What bacteria can be detected with nitrite detection method?

Answer 26

Lactose positive Enterobactericeae, Staphylococcus, Proteus, Salmonella and pseudomonas

Question 27

What is the use of quantitative or semi-quantitative culture in making a diagnosis for UTI?

Answer 27

To differentiate contamination or genuine bacteriuria

Question 28

What are the methods used in making the culture?

Answer 28

Standard loop | Paper strip, dip slide

Question 29

What is the medium used in making a diagnosis for UTI?

Answer 29

CLED agar; inhibit swarming, colony morphology

Question 30

Give an account for the use of Standard loop method

Answer 30

Quantitative way | Spread evenly on agar surface, to differentiate between lactose fermentor or non-lactose fermenter

Question 31

What can be interpretated from the culture results

Answer 31

For mid-stream or clean-catch urine specimens, More than or equal to 10^5 cfu per ml = significant growth

Question 32

Some patients who have UTI do not have elevated counts, who are they?

Answer 32

Pregnant women | Men

Question 33

What should be practised during specimen collection?

Answer 33

Avoid cleaning with antiseptic, which may contaminate urine (false negative) Whip in backward direction

Question 34

What are the possible reasons for false positive results?

Answer 34

Heavy colonisation of vagina | Delay transport of urine sample (more than two hours)

Question 35

Name five complications of UTI

Answer 35

``` Asymptomatic bacteriuria Recurrent UTI Catheter related UTI Acute bacterial prostatitis Chronic bacterial prostatitis ```

Question 36

Most of the cases of bacteriuria, no treatment is required for asymptomatic patient, however, what are the patient that require treatment?

Answer 36

Pregnant Found before urological operation Children under age of 5 yr when associated with vesico-urethro reflux

Question 37

What is the overall comments on urological evaluation in young women

Answer 37

Not cost effective

Question 38

When is urological evaluation in young women indicated?

Answer 38

``` Haematuria Pyelonephritis Obstructive symptoms Urea-splitting bacteria Urinary calculi Severe diabetes ```

Question 39

How is catheter related UTI prevented?

Answer 39

Avoid/ removal of catheter Hand washing Maintain closed system

Question 40

What is biofilm?

Answer 40

Biofilm is when bacteria attach to foreign surface (urinary catheter material) to form biofilm

Question 41

What are the symptoms of acute bacterial prostatitis?

Answer 41

Dysuria, frequency High fever -> common Urinary retention -> common Per rectal examination - very tender prostate

Question 42

What are the infectious agents of chronic bacterial prostatitis?

Answer 42

E. coli Enterobacteriaceae Pseudomonas aeruginosa Enterococci

Question 43

What are the associated conditions of chronic bacterial prostatitis?

Answer 43

Retrograde spread of bacteria into prostatic ducts Dysfunctional voiding Previous instrumentation

Question 44

Give an account to the four glass test for chronic bacterial prostatitis.

Answer 44

First 10ml voided Midstream (bladder) Prostatic massage EPS Prostatic secretion/ First 10 ml voided after massage