Acute Lower Respiratory Track Infections

Front 1

What is the definition of Acute bronchitis?

Back 1

Inflammatory condition of tracheobronchial tree

Front 2

When does most acute bronchitis occur?

Back 2

Winter

Front 3

What are the main symptoms of acute bronchitis?

Back 3

Persistant cough in the absence of lower repiratory tract infections

Front 4

What disease is characterized by acute onset of wheezing, hyperaeration, cough, rhinorrhea, tachypnea and respiratory distress within the fist 2 years of life?

Back 4

Brochiolitis

Front 5

What is the most 2 most common cause of bronchiolitis?

Back 5

RSV and Parainfluenza

Front 6

What class of virus is RSV part of?

Back 6

Paramyxoviridae

Front 7

What type of virus is RSV?

Back 7

Enveloped, ssRNA, negative sense

Front 8

What RSV surface proteins are involved in infection and pathogenesis?

Back 8

F (Fusion protein) and G (viral attachment protein)

Front 9

How is RSV diagnosised?

Back 9

Nasal wash, direct atigen test, tissue culture

Front 10

What children are affected by RSV?

Back 10

Virtually all by ages 2-3

Front 11

How is RSV spread?

Back 11

Inoculation of virus occur nose or eye

Front 12

RSV is most severe in young infants, despite materal antibody. What does this suggest?

Back 12

Immunologic mechanisms may contribute to pathogenesis

Front 13

What does RSV infection look like in adults with normal immune function?

Back 13

Severe cold-like illness, bronchitis, or bronchitis and otitis

Front 14

What does RSV look like in immunocompromised adults/ elderly people?

Back 14

severe and mimics the disease seen in children

Front 15

What treatment is used for RSV?

Back 15

Supportive care
Aerosol Ribivarin in hospitalized infants
Passive immunizaton

Front 16

What two type passive immunization for RSV are available for high risk children?

Back 16

RSVIG (immunoglobulin)
Palivizumab (antibody reactive to F protein)

Front 17

What type of virus is Parainfluenza?

Back 17

Paramxyovirus, Single strand, negative RNA

Front 18

What distiquishes Parainfluenza from other paramxyoviruses?

Back 18

Presence of envelope glycoprotein neuraminidase and hemagglutinating properties

Front 19

How does Parainfluenza bind to sialic acid receptors?

Back 19

Hemagglutinin-neuraminidase (HN) protein

Front 20

How is Parainfluenza diagnosised?

Back 20

Nasal wash with DFA for rapid diagnosis
Cell culture gold standard

Front 21

What is laryngotracheobronchitis?

Back 21

croup

Front 22

What is the leading cause of croup?

Back 22

croup

Front 23

What range of symptoms can parainfluenza cause?

Back 23

From common cold to otitis media to URT

Front 24

What disease is characterized by hoarseness and eepening cough, non productive cough with a striking brass tone?

Back 24

Croup

Front 25

How long does croup last?

Back 25

3-4 days but cough may be longer

Front 26

What is used to treat croup?

Back 26

Supportive

Front 27

What type of virus is Human metapneumovirus?

Back 27

Paramyxovirus

Front 28

What is the clinical manifestation of Human metapneumovirus?

Back 28

Similar to RSV
ranges from asymptomatic to bronchiolitis to pneumonia

Front 29

What maybe causing severe disease in RSV patients?

Back 29

Coinfections of RSV and HMPV

Front 30

How is HMPV diagnosised?

Back 30

PCR but not routine because genome owned by company

Does not grow on commonly used cell lines

Front 31

What illness is caused by infection of the lung parenchyma involving the alveoli or interstitium?

Back 31

Pneumonia

Front 32

What is lobar pneumonia?

Back 32

Distinct region of lung involved with the most invovement within the alveoli

Front 33

What is bronchopneumonia?

Back 33

Pneumonia involving small airways and nearby areas of the lung

Front 34

What pneumonia involves lung interstitium?

Back 34

Interstitial pneumonia

Front 35

How is acute pneumonia diagnosised?

Back 35

Clinically: patients signs and symptoms and x-ray

Front 36

Why is it difficult to determine etiologic agent involved in pneumonia?

Back 36

lots of different agents with different growth requirements and difficult to get specimen

Front 37

What are common causes of community-acquired pneumonia?

Back 37

Streptococcus pneumoniae, Haemophilus influenzae, staphlococcus aureus, moraxella catarrhalis, mycoplasma pneumoniae, chlamydophila pneumoniae, Legionella pneumophila, Klebsiella pneumoniae

Front 38

What are common causes of hospital-acquired pneumonia?

Back 38

aerobic gram negative bacilli (E. coli, Serratia, Enterobacter, Klebsiella, Pseudomonas aeruginosa) and Staphylococcus aureus

Front 39

What is the general route of infection for pneumonia?

Back 39

reach lung, avoid host defenses, multiplication and host response, cleared or patient dies

Front 40

What is structure of strep. pneumoniae?

Back 40

Gram postive cocci, catalase negative, pairs or short chains

Front 41

Why does strep. pneumoniae frequently appear gram negative?

Back 41

Presence of autolysins

Front 42

What is the leading cause of community-acquired pneumonia especially in the elderly and immunocomprimised patients?

Back 42

Strep. pneumoniae

Front 43

How is strep. pneumoniae spread?

Back 43

person-to-person via close contact

Front 44

What does strep. pneumoniae bind to prevent it from being trapped in mucous?

Back 44

secretory portion of IgA

Front 45

What two thing allow strep. pneumoniae to avoid phagocytosis?

Back 45

Capsule and pneumolysin

Front 46

How does the capsule of strep. pneumoniae aid avoidance of phagocytosis?

Back 46

high antigenic variablility, binds protein H which then degrades C3b, prevents phagosome from encountering antibody or complement

Front 47

How does pneumolysin prevent phagocytosis of strep. pneumoniae?

Back 47

Decrease oxidative burst therefore PMN are not as affective

Front 48

What mediates the inflammatory response caused by strep. pneumoniae?

Back 48

Teichoic acid

Front 49

How does teichoic acid work?

Back 49

binds to TLR2 which stimulates cytokine release

Front 50

What organ is critical for recovering for strep. pneumoniae?

Back 50

Spleen

Front 51

What 3 groups of people are at great risk for infection with strep. pneumoniae?

Back 51

1)loss of splenic function
2)decreased responsiveness to polysaccharide antigens
3)increased rate of decline in serum antibody concentrations

Front 52

What is the leading cause of bacterial meningitis in US?

Back 52

Strep. pneumoniae

Front 53

What complications can arise from strep. pneumoniae?

Back 53

empyema, bacteremia, meningitis, otitis media and sinusitis

Front 54

What are the clinical features of strep. pneumoniae?

Back 54

abrupt onset of fever, shaking chills, chest pain, cough with purulent (and often bloody) sputum, tachypnea and tachycardia

Front 55

What drug is used to treat strep. pneumoniae?

Back 55

Penicillin but lots of resistance

Front 56

What type of hemolytisis does strep. pneumoniae exhibit?

Back 56

alpha

Front 57

What are the two types of strep. pneumoniae vaccines?

Back 57

adult (23 capsular polysaccharide types) and child (7 capsular types conjugated to proteins)

Front 58

What type of bacteria is Haemophilus influenzae?

Back 58

extracellular, gram negative coccobacilli

Front 59

What allows haemophilus influenzae to adhere to mucosal epithelial cells?

Back 59

Pili

Front 60

What is the basis of the Haemophilus influenzae B vaccine?

Back 60

capsule

Front 61

What does H. influenzae colonize?

Back 61

pharynx, occ. conjunctiva or genital mucosa

Front 62

How is H. influenzae spread?

Back 62

airborne droplets or direct contagion

Front 63

What is the clinical presentation of non-encapsulated strains of h. influenzae?

Back 63

exacerbations of chronic bronchitis, otitis media, sinusitis, occasionally pneumonia

Front 64

What is the clinical presentation of encapsulated strains of h. influenzae?

Back 64

Pneumonia, epiglottitis, miningitis, cellulitis, septic arthritis

Front 65

What drugs are used to treat H. influenzae?

Back 65

third generation cephalosporins

Front 66

How is H. influenzae diagnosised?

Back 66

grown on chocolate agar,
gram stain tiny, pleomorphic, gram negative bacilli/coccobacilli

Front 67

What type of bacteria is Klebsiella pneumoniae?

Back 67

Extracellular, Gram negative bacilli

Front 68

Where is Klebsiella pneumoniae normaly found

Back 68

GI tract

Front 69

What family is Klebsiela pneumoniae part of?

Back 69

Enterobacteriaciae

Front 70

What subgroup of patients is Klebiella pneumoniae normally found?

Back 70

Alcoholics and other compromised hosts

Front 71

What can be used to treat Klebiella pneumoniae?

Back 71

Pretty much nothing... most is drug resistant

Front 72

Describe Pseudomonas aeruginosa bacterial characteristics?

Back 72

Gram negative, oxidase-positive, motile, aerobic organism

Front 73

Where does Pseudomonas aeruginosa grow?

Back 73

Water

Front 74

Name some of the virulence factors used by Pseudomonas aeruginosa.

Back 74

Fimbriae, Slime, Pyocyanin, proteases, elastases, phospholipase, exoenzymes, hemolysins, Exotoxin A, Endotoxin, Multiple antibiotic resistance

Front 75

How do fimbriae aid in Pseudomonas aeruginosa virulence?

Back 75

involved in adherence but do not adhere well to fibronectin

Front 76

How does slime aid in Pseudomonas aeruginosa virulence?

Back 76

Acts like capsule and helps make biofilm

Front 77

Why are patients with cystic fibrosis more succeptible to Pseudomonas aeruginosa?

Back 77

conditions may switch on gene to make slime

Front 78

How does the blue green pigment pyocyanin aid in Pseudomonas aeruginosa virulence?

Back 78

Catalyzes formation of toxic radicals, stimulates IL-8 release

Front 79

What enzymes produced by Pseudomonas aeruginosa cause tissue damage?

Back 79

Proteases, elastases, phospholipase, exoenzymes, hemolysins

Front 80

What kind of heymolysis is seen with Psuedomonas aeruginosa?

Back 80

Beta

Front 81

How does Exotoxin A aid in Pseudomonas aeruginosa virulence?

Back 81

functions identical to diptheria exotoxin but less potent

Front 82

What 5 groups of patients are most suceptible to Pseudomonas aeruginosa?

Back 82

Burn patients, cystic fibrosis patients, agranulocytic patients, patients with malignancy or prolonged immunosuppressive therapy, patients on repiratory equipment

Front 83

What does Pseudomonas aeruginosa cause in normal hosts?

Back 83

Swimmer's ear or folliculitis