Chlamydia, Mycoplasma, Rickettsia, Erlichia, Bartonella

Question 1

What do mycoplasma lack?

Answer 1

> lack cell wall - resistance to antibiotic (beta lactams = targeting cell wall synthesis)

> NO gram stain reaction - no cell wall

Question 2

Why are mycoplasma resistant to antibiotics like beta lactams?

Answer 2

> beta lactams antibiotics affect cell wall synthesis
doesn’t work for mycoplasma
no cell wall

Question 3

Why is there no gram stain reaction for mycoplasma?

Answer 3

no cell wall - no peptidoglycan

Question 4

Outline species of mycoplasma?

Answer 4

> mycoplasma pneumoniae
mycoplasma hominis
mycoplasma genitalium

Question 5

Outline species of ureaplasma?

Answer 5

> ureaplasma urealyticum

Question 6

Area mycoplasma eukaryotes or prokaryotes?

Answer 6

prokaryotes

Question 7

What is special about mycoplasma?

Answer 7

> smallest free living self-replicating microorganism

> no cell wall

Question 8

What do mycoplasma have in their cell membrane?

Answer 8

> sterols

> helps with membrane fluidity

Question 9

How many layers in cell membranes of mycoplasma?

Answer 9

3 layers

Question 10

What organelle do mycoplasma have at the tip?

Answer 10

attachment organelle

Question 11

What do these attachment organelles have?

Answer 11

adhesion protein

Question 12

What is a growth requirement for mycoplasma? what does this mean?

Answer 12

fastidious - specific requirements needed for growth

Question 13

Is mycoplasma fast growing or slow growing?

Answer 13

slow growing

Question 14

What type of anaerobes are mycoplasma? What does this mean?

Answer 14

factulatitve anaerobes

> survive in oxygen present and no oxygen conditions

Question 15

Mycoplasma are saprophytic, what does this mean?

Answer 15

> present mainly in skin + mouth

Question 16

What growth medium is used for mycoplasma?

Answer 16

> enriched media

> PPLO (pleuropneumonia like organisms) agar + broth

Question 17

What does PPLO broth contain?

Answer 17

> beef heart infusion
peptone
yeast extract
20% horse/ heart serum

Question 18

What is a special requirement for ureaplasma for their growth?

Answer 18

> urea

Question 19

What unique colonies doe mycoplasma form in agar?

Answer 19

> fried eggs colonies

Question 20

Outline how mycoplasma are different to normal bacterium?

Answer 20

> no genetic inheritance from parent bacteria (each bacteria is different)
require cholesterol for growth (cell membrane)
grow slowly + v.small size
low turbidity in liquid medium

Question 21

What shape do mycoplasma have?

Answer 21

> polymorphic

Question 22

Is mycoplasma a virus?

Answer 22

> no - similar but not virus

> living organism

Question 23

Pathogenic factors of mycoplasma?

Answer 23

> ATTACHMENT organelle (no cell wall)

> ADHERENCE = adhesion P1 (protein) > adhere to cilia

> H2O2 > destroy cilia

> endotoxins

> COLD AGGLUTININS produced by immune system in response to infection > these agglutinins Ab react + attach own body RBC

Question 24

Where are mycoplasma most commonly found on? What type of disease does this cause?

Answer 24

surface of mucous membranes
> respiratory tract
> urogenital tract
> joints

Question 25

Outline common disease of mycoplasma?

Answer 25

> chronic inflammation of respiratory tract > chronic inflammation of urogenital tract > chronic inflammation of joints

Question 26

Most common disease is due to which mycoplasma species?

Answer 26

mycoplasma pneumonia

Question 27

What is incubation period of mycoplasma pneumonia?

Answer 27

1-3 weeks

Question 28

How is m.pneumonia transmitted?

Answer 28

> airbrone dropplets > nasopharyngeal secretions > close contact

Question 29

Onset symptoms of m.pneumonia?

Answer 29

``` > fever > malaise > headache > otitis media (ear inflammation) > blood sputum > pleural effusion (fluid in pleural space) > long covalences (recovery period) ```

Question 30

What specimens are taken for diagnosis of mycoplasma?

Answer 30

> throat swabs > respirsotyr secretions > sputum

Question 31

Why is mycoplasma diagnosis difficult to establish?

Answer 31

> cannot be stained in sputum > require specific mediums PPLO agar or broth > clinical symptoms not specific

Question 32

What are the complications with mycoplasma?

Answer 32

``` > arthritis > due to deposition of complexes > encephalitis > common infants > aseptic meningitis > CNS > Guillain-Barre syndrom > pericarditis > pancreatitis > haemolytic anaemia (cold agglutinins) ```

Question 33

Which type of immunity if involved in mycoplasma ?

Answer 33

> humoral immunity

Question 34

Outline specific response of the humeral immunity for mycoplasma?

Answer 34

> secretory IgA > complement fixing IgG > cold agglutinins

Question 35

How can mycoplasma be identified in agar?

Answer 35

> form fried eggs like colonies

Question 36

What stain is used to identify colonies of mycoplasma?

Answer 36

Diene's stain

Question 37

What tests can be used for mycoplasma?

Answer 37

> growth inhibition test (adding antisera) > immunofluorescence on colonies > DNA test

Question 38

Outline species of ureaplasma?

Answer 38

> Ureaplasma urealyticum | > Ureaplasma paramu

Question 39

How do ureaplasma differ from mycoplasma?

Answer 39

> DO NOT FERMENT > don't ferment carbs + amino acids (mycoplasma do ferment) > depends on hydrolysis of urea