(mostly) Respiratory Diseases

Question 1

How do mycobacterium stain?

Answer 1

acid-fast

Question 2

What is the primary virulence factor of mycobacterium?

Answer 2

cord factor

Question 3

What is the treatment for M. tuberculosis?

Answer 3

HERZ:

isoniazid
ethambutol
rifampin
pyrazinamide

Question 4

How do M. tuberculosis live in macrophages?

Answer 4

prevent phagolysosome fusion

Question 5

What Mycobacterium causes TB-like symptoms in immunocompromised?

Answer 5

M. kansasii

Question 6

Where would you see a case of M. avium, and what is the treatment?

Answer 6

nosocomial infection in AIDS

treat with clarithromycin + ethambutol for life

Question 7

What are the two clinical presentations of M. leprae

Answer 7

tuberculoid leprosy

lepromatous leprosy

Question 8

What is the treatment for M. leprae?

Answer 8

sulfone + rifampin for 6-9 months

Question 9

What is the clinical presentation of Mycoplasm pneumoniae?

Answer 9

“walking” pneumonia (20%)
tracheobronchitis (70%)

insidious onset over 3 weeks; non-productive cough, mild fever, myringitis

Question 10

What does Mycoplasma pneumoniae look like in a culture?

Answer 10

very small “fried-egg” appearance

Question 11

What nutrient does Mycoplasma pneumonia scavenge from it’s host?

Answer 11

sterols (for it’s cell membrane)

Question 12

Why is penicillin uneffective against Mycoplasma pneumoniae?

Answer 12

no cell wall

Question 13

What is the treatment for Mycoplasma pneumoniae?

Answer 13

don’t treat if mild; can use tetracycline or erythromycin

Question 14

What is the clinical presentation of Mycoplasma genitalium, and how is it transmitted?

Answer 14

presents as urethral and genital infections

STD

Question 15

What is the clinical presentation of Mycoplasma hominis?

Answer 15

1 cause of postpartum fever

causes 10% of salpingitis (pelvic inflammatory disease)

Question 16

What is the clinical presentation of Ureaplasma urealyticum, and what is the treatment?

Answer 16

non-gonococcal urethritis and bladder stones

treated with doxycycline

Question 17

What does Corynebacterium diptheriae look like, and how is it cultured?

Answer 17

G+ rod (Chinese character appearance)

grown on tellurite blood agar

Question 18

What is the clinical presentation of C. diptheriae?

Answer 18

sore throat and fever –> pseudomembrane forms at back of throat –> toxin spreads through blood to heart, liver, kidney

Question 19

What virulance factors are found in C. diptheriae, and what test is used to detect toxic strains?

Answer 19

AB toxin (ADP-ribosylates EF-2)

Elek Immunodiffusion test identifies toxic strains

Question 20

What is the treatment/control of C. diptheriae?

Answer 20

control: vaccine (DTaP with Tdap booster every 10 years)
treatment: large doses of equine antitoxin + penicillin/erythromycin to keep bacterial numbers low

Question 21

How does Bordetella pertussis stain?

Answer 21

G- coccobacilli

Question 22

Clinical presentation of B. pertussis?

Answer 22

1-2 wk incubation
Catarrhal stage- low fever, runny nose, cough
Paroxysmal stage- whooping cough
Convalescent stage- less severe cough for ~45 days

Question 23

Virulance factors of B. pertussis?

Answer 23

Fha- binds to ciliated epithelial cells

AB5- ADP-ribosylates inhibitory G protein causing excess cAMP

calmodulin dependent adenyl cyclase

LPS

Question 24

Control and treatment for B. pertussis?

Answer 24

DTaP vaccine

control with erythromycin if in catarrhal stage

Question 25

Why is B. parapertussis less severe than B. pertussis?

Answer 25

no AB5 toxin

Question 26

What does Haemaphilus influenza look like, and how is it cultured?

Answer 26

G- coccobacillus, some have capsule (typable) grown on chocolate blood agar

Question 27

How does H. influenza present in children?

Answer 27

meningitis acute otitis media (#1 cause) bacteremia--> DIC pharyngitis, bronchitis, epiglottidis

Question 28

How does H. influenza present in adults?

Answer 28

pneumonia, sinusitis, epiglottitis most adults are immune

Question 29

What is the control of H. influenza?

Answer 29

DTap + Hib vaccine at 15mo 80% resolves untreated amoxicillin or 3rd gen. cephalosporins rifampin for prophylaxis

Question 30

How does H. ducreyi present and how does it spread?

Answer 30

chancroid (genital ulcers) | STD

Question 31

How is H. ducreyi treated?

Answer 31

macrolides or SxT

Question 32

How is Legionella pneumophilia cultured, and what does it look like?

Answer 32

cultured on charcoal yeast extract agar pleomorphic G- rod

Question 33

What is the clinical presentation of L. pneumophilia?

Answer 33

``` Pontiac fever (1 day flu) Legionnaires disease (acute pneumonia, high fever, fibrin in lower lung) ```

Question 34

How is L. pneumophilia spread and how is it detected?

Answer 34

mechanically aerosolized droplets (grows biofilms in standing water); not transmitted person to person detected with urine antigen test

Question 35

How is Legionnaires' disease treated?

Answer 35

macrolides (usually erythromycin) sometimes quinolones