Abnormal Staining Organisms

Question 1

__________________________________ manifests with atypical pneumonia, a cold agglutinin reaction, and a rash. The cold agglutinin reaction is due to IgM antibodies produced in response to the microbe cross-reacting with an antigen on the host RBC, which causes hemolytic anemia and Raynaud phenomenon.

Answer 1

Mycoplasma pneumonia

Question 2

In a patient with suspected cold agglutinin disease, lower respiratory symptoms and erythema multiforme (annular lesions with a dusky central area) indicate infection by a specific pathogen.

Answer 2

Mycoplasma pneumoniae

Question 3

Mycoplasma pneumoniae infection is most common in what individuals ?

Answer 3

Mycoplasma pneumoniae infection is most common in individuals living in crowded environments (e.g., prisons, military barracks) and those < 30 years of age.

Question 4

Mycoplasma pneumoniae does not appear on Gram staining because it lacks a cell wall, but it can be cultured on __________________

Answer 4

Eaton agar

Question 5

What 3 major groups of bacteria stain abnormally on gram?

Answer 5

Mycobacteria, mycoplasma, and Gardnerella

Question 6

Löwenstein-Jensen agar

Answer 6

A growth medium used to culture Mycobacterium species. Includes components that inhibit the growth of gram-negative and gram-positive bacteria. Evidence of mycobacterial growth can take as long as 8 weeks.

Question 7

A growth medium used to culture Mycobacterium species. Includes components that inhibit the growth of gram-negative and gram-positive bacteria. Evidence of mycobacterial growth can take as long as 8 weeks.

Answer 7

Löwenstein-Jensen agar

Question 8

A cell wall component and virulence factor of M. tuberculosis that stimulates the release of TNF-α and induces granuloma formation by activating macrophages.

Answer 8

Cord factor

Trehalose dimycolate

Question 9

What virulence factor allows TB to evade lysosomal degradation?

Answer 9

Surface glycolipids: (sulfatides) inhibit phagolysosomal fusion

Question 10

Mianstay of treatment for TB

Answer 10

Isoniazid PLUS rifampicin PLUS ethambutol PLUS pyrazinamide

Question 11

This organism can cause all of the following:
(atypical pneumonia)
Cold antibody hemolytic anemia (IgM)
Erythema multiforme
Acute interstitial nephritis
Stevens-Johnson syndrome (affects mostly children and adolescents)

Answer 11

Mycoplasma pneumoniae

Question 12

What virulence factors allow gardernella to cause bacterial vaginosis?

Answer 12

Pili
Capsule
Phospholipase C
Protease
Vaginolysin, cytolysin
Biofilm formation