Mycoplasma & Ureaplasma

Question 1

What are the main structural feature that is unique to mycoplasma/ureaplasma families?
- What are the 3 different types of mycoplasma to know?

Answer 1

• Lack a cell wall and are therefore resistant to penicllins and cephalosporins.
• M. pneumoniae, M. hominus, M. genitalium

Question 2

What makes M. pneumoniae stand out from the rest?

- What is the histologic appearance of M. pneumoniae compared to the the other mycoplasmas?

Answer 2

• it is a strict aerobe as opposed to the rest which are facultative anaerobes.
• m. pneumoniae has a “mulberry” appearnce compared to the rest that have a “fried egg appearance.

Question 3

• What is the virulence factor that allows mycoplasma pneumoniae to attach?
• What is the percentage of US pneumonia cases that M. pneumoniae is responsible for?

Answer 3

• P1 adhesion: interaction with cilia leading to ciliostasis that interferes with normal airway clearance (persistant cough)
• 20%

Question 4

How is M. pneumoniae spread?

What is the most common age of infected individuals?

Answer 4

• via droplets and nasal secretions

- children between 5-15

Question 5

• Which is the more severe pneumoniae atypical or walking pneumonia?
• How does pneumonia appear on xray?

Answer 5

Walking pneumonia

- unilateral

Question 6

What is the classical vingerrette that presents with M. pneumoniae?
What will appear in a gram stain for M. pneumoniae?

Answer 6

• nonpurulent otitis media and lower repiratory tract illness in a teenager should indicate M. pneumoniae.
• Does not gram stain but shows some mononuclear cells

Question 7

What is are unique features of other mycoplasmas?

- When is there an increase in the incidence of M. hominis and M. genitalium?

Answer 7

• M. hominis an M. genitalium have a fired egg appearance on agar and are facultative anaerobe.
• After puberty with the rise in sexual activity

Question 8

What clinical diseases is M. genitalium present with?

What does M. hominis present with?

Answer 8

• M. genitalium: non-gonococcal urethritis

- M. hominis: fever or another non-gonococcal urethritis, pyleonephritis, and pelvic inflammatory disease.

Question 9

What are classic diagnostic signs of M. genitalium and M. hominis?
How are these two spread?

Answer 9

• Fried egg appearance, metabolize arginine but not glucose

- Sexual contact

Question 10

What makes ureaplasma urealyticum different from mycoplasma?

What is its main reservoir?

Answer 10

• urease activity, on agar colonies are small, circular, and grow downward.
• Main reservoir is the genital tract of sexually active men and women

Question 11

What are the symptoms of U. urealyticum?

What is the main diagnostic criteria for U. urealyticum?

Answer 11

• NGC, in women - chorioamnionitis and postpartum fever.

- requires urea for growth, inhibitied by alkalinity resulting from metabolism of urea.