SM 181 Respiratory Bacterial Pathogens

Question 1

What 4 bacteria cause pharyngitis?

Answer 1

Strep pyogenes, Chlamyidiea pneumoniae, Mycoplasma pneumoniae, C. diptheriae

Question 2

Is there a vaccine for C. diptheriae?

Answer 2

Yes, the Diptheria toxoid

Question 3

What 4 bacteria are enterobacteria?

Answer 3

E. coli, Klebsiella, Serratia, Enterobacter

Question 4

Describe the shape and stain of C. diptheriae?

Answer 4

Club shaped Gram positive bacilli

Question 5

Which respiratory pathogen lacks cell walls?

Answer 5

Mycoplasma pneumoniae

Question 6

Describe the shape and staining of Strep pneumo?

Answer 6

Gram positive lancet shaped diplococci

Question 7

What is the effect of diptheria toxin?

Answer 7

Inhibits protein synthesis in pharyngeal epithelial cells, leading to necrosis

Question 8

Where does H. influenzae colonize?

Answer 8

H. influenzae infects the upper respiratory tract of healthy individuals

Question 9

How does C. diptheriae present?

Answer 9

C. diptheriae presents with pseudomembranes in the airways, sore throat, fever

Question 10

What are nocosomial pneumonias?

Answer 10

HAP’s and VAP’s

Question 11

What is the treatment for Mycoplasma pneumoniae?

Answer 11

Macrolides (-mycin), tetracycline, and fluorquinolones

Question 12

Describe the shape and stain of H. influenzae?

Answer 12

Small Gram negative coccobacilli

Question 13

What is the life threatening manifestation of H. influenzae?

Answer 13

Epiglotitis

Question 14

Where does Strep pneuomo colonize?

Answer 14

Oropharynx and nasopharynx

Question 15

What are treatments for Legionella?

Answer 15

Azithromycin or ciprofloxacin

Question 16

What is a community acquired pneumonia?

Answer 16

CAP = pneumonia acquired while in the community

Question 17

How can H. influenzae be diagnosed in ab?

Answer 17

Growth on chocolate agar but not sheep blood, because it requires Hemin and NAD to grow

Question 18

What is the purpose of pneumolysin in Strep pneumo?

Answer 18

Degrades Hemoglobin, forms pores in RBC = alpha hemolysis

Question 19

What are 8 common causes of acute CAP?

Answer 19

Strep pneumo, H. flu, Mycoplasma, Chlamydia Pneumo, S. aureus, Legionella, M. catarrhalis, aspiration pneumonia

Question 20

What disease does Legionella cause?

Answer 20

Legionella causes Legionairre’s Disease

Question 21

How does Strep pneumo show up on culture?

Answer 21

Gram positive diplococci in pairs and chains

Question 22

How does diptheria toxin work?

Answer 22

ADP ribosylation of EF-2

Question 23

How does peptidoglycan contribute to inflammation?

Answer 23

Peptidoglycan activates the complement cascade leading to inflammation and tissue damage

Question 24

Is Strep pneumo optochin susceptible or optochin resistant?

Answer 24

Strep pneumo is optochin susceptible

Question 25

What does aspiration pneumonia look like on CXR?

Answer 25

Consolidation in dependent lung fields

Question 26

What can Mycoplasma pneumoniae cause?

Answer 26

Pharyngitis, CAP

Question 27

What laboratory test can detect Strep pneumo?

Answer 27

Urinary antigen test

Question 28

How does Strep pneumo show up on CXR?

Answer 28

Lobar infiltrate, and may cause empyema

Question 29

What are 4 causes of Ventilator Associated Pneumonia?

Answer 29

S. aureus, Legionella, Pseudomonas, Acinetobacter

Question 30

Which strain of H. influenzae can be prevented and how?

Answer 30

Type B, via capsular conjugate vaccine (Hib)

Question 31

What is Pseudomonas Aeroginosa?

Answer 31

Gram negative aerobic bacilli that frequently causes HAP and VAP, with many antibiotic resistances

Question 32

What type of pneumonia does Legionella cause?

Answer 32

Atypical community acquired or nocosomial pneumonia with very high fever, associated with water towers

Question 33

What are 3 common causes of chronic CAP?

Answer 33

TB, Nocardia, Actinomycines Israelii

Question 34

Describe the shape and stain of Legionella pneumophila?

Answer 34

Legionella is an aerobic Gram negative-like bacillus, but does not take up Gram stain

Question 35

What can H. influenzae cause in adults?

Answer 35

Bronchitis, CAP

Question 36

How can H. influenzae be treated?

Answer 36

Ampicillin if Beta-Lactamase Negative, Cephaolsporins if Beta-lactamase Positive

Question 37

What 5 bacteria can cause acute bronchitis?

Answer 37

Strep pneumo, H. influenzae, Mycoplasma Pneumoniae, Chlamydia pneumoniae, Bordatella Pertussis

Question 38

What are predisposing conditions for a Strep pneumo infection?

Answer 38

Antecedent viral infection like Influenza, HIV, COPD

Question 39

Describe the shape and stain of Staph Aureus?

Answer 39

Gram positive cocci that may have gold appearance

Question 40

Describe the shape and stain of Mycoplasma pneumoniae?

Answer 40

Mycoplasma pneumoniae is an extracellular pathogen that lacks cell walls and is therefore pleimorphic in shape

Question 41

What can cause typical pneumonia?

Answer 41

Strep pneumo, H influenza,

Question 42

What is a ventilator associated pneumonia?

Answer 42

VAP = pneumonia that occurs 48+ hours after mechanical ventilation

Question 43

What bacteria causes aspiration pneumonia?

Answer 43

Fusobacterium

Question 44

Does Mycoplasma pneumoniae cause a typical or an atypical pneumonia?

Answer 44

Atypical pneumonia = gradual onset and cough without sputum, "walking pneumonia" is less severe

Question 45

What is the dot locus?

Answer 45

Defect in organelle trafficking, specific to Legionella, that is used to prevent phagolysosome fusion in host cells

Question 46

Describe the shape of Chlamydia pneumoniae?

Answer 46

Closely related to the STD, causes atypical CAP

Question 47

What is Acinetobacter baumannii?

Answer 47

Gram negative aerobic bacillus or coccobaciluus that causes HAP and VAP, with many antibiotic resistances

Question 48

How is Mycoplasma pneumoniae diagnosed?

Answer 48

Radiographic findings >> clinical findings; CXR shows essentially any pattern; also, via specific antibody titers in the blood

Question 49

What is the treatment of choice for Strep pneumo?

Answer 49

Historically, Penicillin, but resistance has lead to the use of other antibiotics such as vancomycin and cephalosporin

Question 50

What kind of pneumonias do Staph Aureus cause?

Answer 50

CAP and Nocosomial pneumonia

Question 51

How does Strep pneumo present in clinic?

Answer 51

Strep pneumo presents with fever, cough with rusty sputum, and diminished respiration/splinting on the affected side

Question 52

How does aspiration pneumonia present?

Answer 52

Cough, fever, or foul sputum

Question 53

What causes whooping cough?

Answer 53

Bordtatella Pertussis via pertussis toxin

Question 54

How is C. diptheriae treated?

Answer 54

Macrolides like Erythromycin, Penicillin

Question 55

What can H. influenzae cause in children?

Answer 55

Otitus media, sinusitis, meningitis, and pneumonia

Question 56

What are the determinants of pathogenicity for Step pneumo?

Answer 56

Capsule (evade Macrophages), pneumolysin (degrades Hgb), peptidoglycan (Gram+), and IgA protease (cleaves IgA)

Question 57

What is the purpose of the capsule of Strep pneumo?

Answer 57

Evades macrophages, but a target for antibodies

Question 58

Does Strep pneumo only affect healthy or previously ill people?

Answer 58

Both, and can cause pneumonia in both groups

Question 59

What is aspiration pneumonia?

Answer 59

A form of pneumonia seen in patients with depressed gag reflex, such as elderly patients and alcoholics actively blacking out

Question 60

How does Strep pneumo spread?

Answer 60

Person to person via aerosols, and only affects humans

Question 61

What are the treatments for Chlamydia pneumoniae?

Answer 61

Erythromycin and Tetracycline

Question 62

Why is Mycoplasma pneumoniae resistant to penicillins?

Answer 62

It lacks a cell wall, so penicillins can't impair cell wall synthesis

Question 63

How is non-MRSA treated?

Answer 63

Nafcillin

Question 64

Is Strep pneumo catalase positive or catalase negative?

Answer 64

Strep pneumo is catalase negative

Question 65

How does Legionella spread?

Answer 65

Infection may spread via aspiration or inhalation of aerosol

Question 66

How does H. influenzae spread?

Answer 66

Airborne droplets and direct contact with secretions

Question 67

What is a hospital acquired pneumonia?

Answer 67

HAP = pneumonia that occurs 48+ hours after hospitalization

Question 68

What are the two vaccines for Strep pneumo and how are they different?

Answer 68

Pneumococcal polysaccharide vaccine as well as pneumococcoal polysaccharide-protein conjugate vaccine; the polysaccharide-protein conjugate produces specialized T cells and lasting immunity

Question 69

What is the significance of the capsule of H. influenzae?

Answer 69

6 types of a polysaccharide capsule, which is antiphagocytic but susceptible to antibodies; capsulated strains of H. influenzae tend to infect children because they have not yet formed antibodies to the capsule

Question 70

What 3 bacteria cause acute sinusitis?

Answer 70

Strep pneumo, H. flu, M. catarrhalis

Question 71

What protein is important for Mycoplasma pneumoniae pathogenicity?

Answer 71

P1, which allows for extracellular adherence to host cells

Question 72

What distinguishes typical and atypical pneumonia?

Answer 72

Typical pneumonia is abrupt, produces sputum, and makes people very ill; atypical pneumonia is gradual in onset, does not produce sputum, and usually mild

Question 73

How is MRSA treated?

Answer 73

Vancomycin or Linezolid

Question 74

How does Mycoplasma pneumoniae spread?

Answer 74

Person to person via aerosols