respiratory infections

Question 1

what are the common bacteria that cause respiratory infections?

Answer 1

S. pneumoniae
H. influnzae
M. catarrhalis
S. aureus
B. pertussis
S. pyogenes
M. tuberculosis

Question 2

what are the atypical respiratory infection bacteria?

Answer 2

mycoplasma pneumonaie
chlamydia pneumoniae
legionella pneumophila

Question 3

what makes atypical resp infection bacteria atypical?

Answer 3

because they are not susceptible to beta lactam antibiotics

Question 4

why is Mycoplasma pneumoaie atypical?

Answer 4

they dont have a cell wall (which is the target of beta lactams)

Question 5

why is Chlamydia pneumoniae atypical

Answer 5

they dont have bacterial cell wall (no peptidoglycan) which is the target of beta lactams

Question 6

why is legionella pneumophila atypical?

Answer 6

it is intracellular (beta-lactams can’t get into the cell)

Question 7

what is commonly used to culture respiratory infections?

Answer 7

sputum - it is graded off how little epithelial cells are in it (q0 to q3)

Question 8

what are they types of pneumonia?

Answer 8

CAP (community acquired)
HAP (hospital acquired)
VAP (ventilator associated)

Question 9

what does pnuemonia cause?

Answer 9

inflamed lungs - primarly the alveoli)

Question 10

what are the symptoms of penumonia?

Answer 10

chest pain
shortness of breath
fever
dry/productive cough

Question 11

what is pneumonia caused by?

Answer 11

strep pneumo

Question 12

what is the most important virulence factor in strep pneumo?

Answer 12

the capsule

Question 13

are everyone infected with strep pneumo sick?

Answer 13

no - it colonizes the nasopharynx of 5-10% of adults and 20-40% of kids

Question 14

how do we protect against pneumonia?

Answer 14

Pneumovax (old - not well tolerated because it is a carbohydrate vaccine)
PREVNAR (new - protein conjugated vaccine)

Question 15

who do we give pneumonia vaccines to?

Answer 15

give both to older adults
give PREVNAR to children to protect against pneumo meningitis

Question 16

what is COPD?

Answer 16

umbrella term referring to progressive lung disease characterized by progressively worse breathlessness

Question 17

what are some illnesses covered under COPD?

Answer 17

emphysema, chronic bronchitis refractory asmtha

Question 18

what is COPD usually caused by?

Answer 18

H. influenzae

Question 19

what is H. influenzae?

Answer 19

causes COPD
g- bacillli that requires X and V factors to grow
can be encapsulated or not

Question 20

how can you grow H. influenzae?

Answer 20

on chocoalte agar or blood agar with S. aureus to break open RBCs

Question 21

what are the types of H. influenzae?

Answer 21

type b - encapsulated - vaccinated against - most severe illness
non-encapsulated - causes illnesses, not as severe

Question 22

how is COPD treated?

Answer 22

amoxicillin, or ammoxicillin-clavulanate (for the 18% of H. influenza that produce beta-lactams)

Question 22

what is Legionella pneumonphila

Answer 22

g- bacilli that is widespread in the environment and is usually harmless (except for immunocompromised)

Question 23

how does legionella pnuemophila grow?

Answer 23

needs L-cystein - on BYCE agar

Question 24

how do you detect legionella?

Answer 24

urine antigen test or culture on BYCE agar

Question 25

how do you treat legionella?

Answer 25

fluoroquinalones (or macrolides as an alternative)

Question 26

what bacteria do you not need to test susceptibility for?

Answer 26

legionella pneumo

Question 27

what is bordetella pertussis?

Answer 27

g- aerobic fastidious coccibacilli that causes whooping cough

Question 28

how do you grow B. pertussis?

Answer 28

on BG or RL medium

Question 29

how do you diagnose B. pertussis?

Answer 29

nasopharyngeal specimin/swab and PCR (or BG and RL culture)

Question 30

what are the stages of whooping cough?

Answer 30

catarrhal stage paroxysmal stage convalescent stage

Question 31

what is the incubation period of B. pertussis?

Answer 31

4-21 days, usually 7-10

Question 32

what happens in the catarrhal stage of whooping cough?

Answer 32

lasts 1-2 weeks non-specific symptoms (sneezing, mild cough, fever, etc)

Question 33

what happens in the paroxysmal stage of whooping cough?

Answer 33

lasts 1-6 weeks paroxysmal cough (with the whoop sound) posttussive committing, cyanosis, and exhaustion

Question 34

what happens in the convalscent stage of whooping cough?

Answer 34

lasts 2-3 weeks symptoms gradually resolve

Question 35

what is the treatment for whooping cough?

Answer 35

macrolides

Question 36

what is bacterial pharyngitis caused by?

Answer 36

Primarily group A strep (strep. pyogenes)

Question 37

what is the treatment of bacterial pharyngitis?

Answer 37

Penicillin - they are never resistant pen or amoxicillin resistant (beta-hemolytic)

Question 38

what are the complications of bacterial pharyngitis?

Answer 38

rheumatic heart disease (preventable) post-strep glomerulonephritis (not preventable)

Question 39

what does penicillin treatment do in bacterial pharyngitis?

Answer 39

shortens illness by 18-20 hours BUT prevents spread and rheumatic heart disease

Question 40

what is Mycobacterium tuberculosis?

Answer 40

aerobic, very slow to grow, acid fast bacteria

Question 41

why is M. tuberculosis level 3?

Answer 41

because the infective dose is so low (less than 10 cells)

Question 42

how is tb transmitted?

Answer 42

through airborne droplets (talking, coughing, sneezing)

Question 43

what happens to people who come into contact with M. tuberculosis?

Answer 43

5% of people infected develop pulmonary tb 95% have dormant tb in lung tubercules (5% of these people will reactivate tb over their lifetime) ~2% form disseminated tb (from opening tubercle into bronchus or blood vessel erosion)

Question 44

how is tb tested?

Answer 44

2-step skin test where it is injected into skin

Question 45

what is a further test for tb after the skin test?

Answer 45

iferon gamma-release assay (IGRA)