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Flashcards in Microbiology Deck (56)
1

The presence of micro-organisms in the urinary tract that are causing clinical infection

UTI

2

Lower UTI

infection confined to the bladder (cystitis)

3

Upper UTI

Kidneys +/- ureters

4

Complicated UTI

UTI complicated by systemic sepsis or urinary structural abnormality or stones

5

Bacteruria and antibiotics?

Doesn't always require antibiotics

6

Normal bacteria found in the lower end of the urethra?

Coliforms and enterococci

7

Gram negative bacillus but not a coliform
Associated with catheters and UT instrumentation

Pseudomonas aureginose

8

Antibiotic that can be used to treat pseudomonas aeruginosa?

Ciprofloxacin

9

CSU

Catheter specimen urine

10

Which container should you use for urine?

Boricon container
(red top and contains boric acid to stop bacteria from multiplying)

11

White top container?

Sterile universal container
-must reach lab within 2 hours of collection and so not used that routinely

12

What does leukocyte esterase indicate?

Indicates the presence of leukocytes (WBC) in the urine

13

Nitrites in the urine?

Nitrites indicate the presence of bacteria in the urine
Some bacteria can reduce nitrates to nitrites – mainly coliforms – Enterococcus spp. do NOT give positive test

14

Which bacteria can reduce nitrites to nitrates and therefore give a negative nitrite test?

Mainly coliforms - enterococcus

15

Significance of ESBL?

Extended - spectrum beta-lactamse
-Makes bacteria resistant to ALL cephalopsorins and to almost all penicillins

16

ESBL makes bacteria resistant to what?

All cephalosporins and almost all penicillins

17

Antibiotics that may be useful ofr antibiotic resistant ESBL-producing bacteria

Nitrofurantoin (oral), pivmecillinam (oral) fosfomycin (oral), temocillin (IV), meropenem(IV), ertapenem (IV)

18

To whom do Kass's criteria apply to?

Women of child bearing age

19

Where do they think ESBL-producing bacteria might come from?

Chickens, lol

20

CPE

Carbapenemase-producing Enterobacteriaceae

21

Which gram negative (coliform) bacilli are resistant to meopenem?

CPE

22

Some strains are associated with travel to the Indian sub-continent

CPE

23

How many days usually needed to treat uncomplicated lower UTI in women?

3 day course

24

1st line antibiotics for UTI?

Amoxicillin
Trimethoprim
Nitrofurantoin
Gentamicin

25

2nd line antibiotics for UTI?

Pivmecillinam
Temocillin
Cefalexin
Co-amoxiclav
Ciprofloxacin

26

Is amoxicillin safe in pregnancy?

Yes

27

Antibiotic that could treat Enterococcus faecalis and some coliforms?

Amoxicillin

28

How does trimethoprim work?

Inhibits folic acid synthesis

29

Trimethoprim is usually given oral, how would you give it IV?

Co-trimoxazole

30

Risk of what from sulphonamide?

Stevens-Johnson syndrome

31

What is Stevens-Johnson syndrome?

Its a form of toxic epidermal necrolysis

32

Range of organisms treated by trimethoprim?

Most coliforms, including staph aureus but not psuedomonas

33

Which type of UTI is Nitrofurantoin used in?

Nitrofurantoin only useful in lower uncomplicated UTIs as only reaches effective concentrations in bladder urine

34

When should you avoid Nitrofurantoin in pregnancy?

Avoid in late pregnancy (can cause neonatal haemolysis), breast feeding and children <3 months old

35

Why should you avoid nitrofurantoin in late pregnancy?

Can cause neonatal jaundice

36

How many days can you prescribe gentamicin for?

Can only prescribe for 3 days

37

Gentamicin and pregnancy?

AVOID!

38

Gentamicin will not treat what?

Enterococcus

39

Dosage and measuring gentamicin?

Given once daily – 7mg/kg (ideal body weight) then measure a blood level 6-14 hours later.

40

Side effects of gentamicin?

Renal and VIIIth nerve damage

41

Pivemecillinam uses and pregnancy

Good for ESBL bacteria
Not recommended in pregnancy

42

When might you use Temocillin?

Useful for treating complicated UTI/urosepsis in patients whose renal function is too poor for gentamicin, but is NOT as effective as gentamicin clinically
NO activity against Staphs/Streps/Enterococci or Pseudomonas sp.

43

Is cefalexin safe in pregnancy?

Yes

44

Why might you not give cefalexin?

It is a cephalosporin --> risk of C. difficile infection

Cefalexin is a broad spectrum and not really used unless organism is amoxicillin and trimethoprim resistant

45

Inhibits bacterial DNA gyrase, which prevents "supercoiling" of bacteria

Ciprofloxacin

46

Only oral antibiotic used to treat Pseudomonas?

Ciprofloxacin

47

Empirical treatment for Female lower UTI

Trimethoprim or nitrofurantoin orally (3 days)

48

Empirical treatment for Uncatheterised male UTI

Trimethoprim or nitrofurantoin orally (7 days)

49

Empirical treatment for Complicated UTI or pyelonephritis (GP)

Co-amoxiclav or co-trimoxazole (14 days)

50

Empirical treatment for Complicated UTI or pyelonephritis (Hospital)

Amoxicillin and gentamicin IV for 3 days (cotrimoxazole and gentamicin if penicillin allergy), stepdown as guided by antibiotic sensitivities

51

Asymptomatic bacteruria in pregnancy?

-All women screened at 1st antenatal visit
-Usually treated with antibiotics in pregnancy

(if left untreated:
-20-30% progress to pyelonephritis
-May lead to intra-uterine growth retardation or premature labour)

52

Pregnancy risks associated with asymptomatic bacteruria?

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

53

Abacterial cystitis/urethral syndrome?

Patient has symptoms of UTI
Pus cells present in urine, but no significant growth on culture
May be an early phase of UTI
May be due to urethral trauma - “honeymoon cystitis”
May be due to urethritis caused by chlamydia, gonorrhoea
Alkalinising the urine may help (symptomatic relief)

54

Gram negative bacillus but not a coliform
Associated with catheters and UT instrumentation
resistant to most oral antibiotics except ciprofloxacin

Psuedomonas aeruginosa

55

Staphylococcus saphrophyticus is associated with who?

Women of child bearing age

(Its a type of coagulase negative staph)

56

Associated with the formation of stones (calculi)
Foul smelling
Produces urease which breaks down urea to form ammonia, which increases urinary pH - precipitation of salts

Proteus