LTR infections

Question 1

What is the virulencce of LTR pathogens partl dependent on? Name a virulence factor associated with this

Answer 1

Evase of phagocytosis, capsule

Question 2

Infectious agents enter LTR by?

Answer 2

• Inhaling aerosolised material
• Aspiration of UTR commensals (content of stomach inhaled)
• Haematogenous spread (descending infection, but can be seeded from the blood, usually it’s the other way round)

Question 3

Community-aquire pneuomonia is split in two types

Answer 3

• Acute lobar pneumonia
• Atypical pneumonia

Question 4

What is hospital-aquired pneumonia?

Answer 4

• Pneumonia occurring in patients hospitalised for >72 hours

Question 5

Ventillator-associated pneumonia

Answer 5

• Pneumonia occurring in patients mechanically ventilated for >48 hours

Question 6

Community aquired bacterial pneumonia in neonates: bacterial causative agents

Answer 6

Group B strep
L. monocytogenes

Question 7

Community aquired bacterial pneumonia in infants: bacterial causative agents

Answer 7

Encapsulation bacteria (S. pneumoniae, M. pneumoniae, C. pneumoniae

Question 8

Community aquired bacterial pneumonia in children to young adults: bacterial causative agents

Answer 8

Encapsulation bacteria (S. pneumoniae, M. pneumoniae, C. pneumoniae

Question 9

Community aquired bacterial pneumonia in older adults: bacterial causative agents

Answer 9

S. pneumoniae.
Legionella spp.

Question 10

Causative agents of hospital-aquired pneumonia

Answer 10

• P. aeurginosa, other Gram-negative bacilli

Question 11

Institulionalised pneumonia causative agent

Answer 11

G-ve bacilli, S.aureus MRSA

Question 12

Pneumonia in CF patients is caused by (3)

Answer 12

P. aeruginosa, Burkholderia cepacia complex, S.aureus

Question 13

Pneumonia in AIDS pateitns is caused by

Answer 13

Pneumocystis jiiroveci

Question 14

Lobar pneumonia meaning

Answer 14

Pneumonia affecting the discrete lobe in the lung

Question 15

Lobar pneumonia is almost always caused by…

Answer 15

Strep. pneumoniae

Question 16

Why is lobar pneumonia sputum sample difficult?

Answer 16

Goes through mouth

Question 17

Strep. pneumonia morphology

Answer 17

Gram+ve coccus (lanceolate)

Question 18

Strep. pneumoniae type haemolysis

Answer 18

Alpha

Question 19

What is Strep. pneumoniae sensitive to

Answer 19

Optochin

Question 20

Pathogenicity of Strep. pneumoniae depends on?

Answer 20

Capsule

Question 21

Brochnopneumonia

Answer 21

Diffuse lung infection

Question 22

What causes brochnopneuomia

Answer 22

S. aureus

Question 23

Bronchopneumonia is what degree of infection

Answer 23

Secondary, follows viral infection

Question 24

Bronchopneumonia sputum looks like ____ and _____

Answer 24

plums and custard

Question 25

Other bacterial causes of bronchopneumonia

Answer 25

K. pneumoniae, Coliforms and P. aeruginosa.

Question 26

Necrotising pneumonia is caused by S.arueus producing what

Answer 26

Elaborating Panton-Valentine leukocidin, destroying leukocytes

Question 27

Legionarraies disease is regarded to as atypical or typical pneumoniae

Answer 27

Atypical

Question 28

What bacterium caused Legionarraire's disease, gram stain, shape

Answer 28

Legionella pneumophilia, g-ve, bacillus (poor stain)

Question 29

Legionarraire's disease on an x-ray is visualised as what

Answer 29

White out, lung filled with infiltrate

Question 30

Where is Legionella pneumophilia found, spread through what

Answer 30

Lake, river, ponds, stagnant water. Aerosilation

Question 31

Symptoms of Legionarraire's disease

Answer 31

Initially like flu, progress to systemic

Question 32

Other names for atypical pneumonia

Answer 32

Walking pneumonia, non-cultivable pneumonia

Question 33

Patients with atypical pneumonia present with what type of cough, symptoms and x-ray visualisation

Answer 33

* Patients present with dry, unproductive coughs * Fever, myalgia, headache * Little to no evidence of consolidation on X-ray

Question 34

Why can't we use penicillin against atypical pneumoniae

Answer 34

Most bacteria lack cell wall

Question 35

Bacteria that can cause atypical pneumonia

Answer 35

* Mycoplasma pneumoniae * Chlamydophila pnemoniae * Coxiella burnetii (Q fever) * Chlamydophila psittaci (psittacosis)

Question 36

What antibiotic is used to treat atypical pneumonia

Answer 36

Erythromycin

Question 37

How is pneumonia diagnosed in the clinic

Answer 37

* “CURB65” score of severity in CAP: o Confusion o Urea >7mmol/L o Respiratory rate >30/min o Blood pressure <90mmHg systolic o Age >65 years * Score 0-1 = Discharge, oral antibiotics, 2 = Observe in hospital ,3-5 = Admission to hospital * X-ray * Ultrasound (? Empyema, pus in a cavity, pulmonary empyema, collapse)

Question 38

Labratory diagnosis of pneumonia

Answer 38

MC&S

Question 39

Types of sputum to sample

Answer 39

 Induced sputum, saline used  Expectorated sputum, wait till patients coughs it up  Contamination, very prone at is travels via UTR

Question 40

Other choices of sample apart from sputum

Answer 40

* Broncho-alveolar lavage – collect washing * Blood culture * Urine (antigen detection)

Question 41

What bacteria causes Whooping cough: give shape and gram stain

Answer 41

Bordetella pertussis, small G-ve cocco-bacili

Question 42

How does B. pertussis cause whooping cough

Answer 42

Adheres to trachea and interferes with mucociliary escalator- accumulation of mucus and toxin mediated (PT and AC). Restriction of the airway, narrow.

Question 43

Key symptom of whooping cough

Answer 43

paroxysmal coughing usually ends in a high-pitched inspiration

Question 44

Is there a vaccine for whooping cough

Answer 44

yes

Question 45

Why is B. pertussis difficult to cultivate

Answer 45

Due to inhibitory factors in the lung

Question 46

What type of toxin is pertussis

Answer 46

AB5 toxin

Question 47

MOA of pertussis toxin

Answer 47

Causes mass production of cAMP, inhibits inflammatory processes and recruitment of immune system. Evade immune defences.

Question 48

How many domains does pertussis toxin have

Answer 48

Two. AC domain induces large amounts of cAMP, RTX is a pore former and more toxin inside --> cell death

Question 49

Wat is pertussis toxin production controlled by

Answer 49

BvgAS, environmental swithc

Question 50

Respiratory tuberculosis is caused by bacterial species:

Answer 50

* Mycobacterium tuberculosis * M. bovis * M. avium-intracellulare complex * (MAC) * M. kansasii * Obligate aerobes (= upper lobe disease)

Question 51

What LTR is a granultmatous disease

Answer 51

TB

Question 52

TB is resistant to what type of killing through what

Answer 52

Resistant intracellular killing resisting phagosome/lysosome fusion:

Question 53

How is TB spread

Answer 53

Infectious droplets

Question 54

Where does latent TB reside

Answer 54

Survives in macrophages, resides in granulomas

Question 55

Diagnosis of TB

Answer 55

Direct observation in sputum/BAL Culture MGIT NAAT Interferon gamma release assay

Question 56

TB symptom that isn't very diagnosist

Answer 56

Caseous necrosis