Bacterial Respiratory Infections

Question 1

what protective mechanisms do the lungs and bronchi have against infection?

Answer 1

cilia

Question 2

how does the cilia in smokers increase the risk of infection?

Answer 2

slower cilia movement = more time for bacteria to reproduce

Question 3

what does the upper respiratory tract consist of?

Answer 3

• nasal cavity
• throat (pharynx)
• nostrils
• mouth
• voicebox (larynx)

Question 4

what does the lower respiratory tract consist of?

Answer 4

• trachae
• lungs
• bronchi

Question 5

what is the strategy of pathogens when infecting the respiratory system?

Answer 5

• avoid mucus
• resist phagocytosis by alveolar macrophages
• survive and multiply in macrophages

Question 6

what are the most common upper respiratory tract infections?

Answer 6

viruses, e.g. cold

Question 7

what are the most common lower respiratory tract infections?

Answer 7

flu, pneumonia, bronchitis

Question 8

give 6 examples of bacteria that affect the lower respiratory tract

Answer 8

Legionella pneumophila
Strep pneumoniae
Mycoplasma
Haemophilus influenzae
Bordetella pertussis
Hospital acquired Gram negatives

Question 9

give 3 examples of viruses that affect the lower respiratory tract

Answer 9

Parainfluenza
Adenovirus
Influenza virus

Question 10

what kinds of fungi infect the lower respiratory tract and in which patients?

Answer 10

Pneumocystis - people with AIDS

Aspergillosis

HIV positive patients

Question 11

name a gram positive organism that causes nosocomial pneumonia

Answer 11

staph aureus

Question 12

name a gram negative organism that causes nosocomial pneumonia

Answer 12

Pseudomonas aeruginosa

Question 13

how long after admission to hospital does a patient get nosocomial pneumonia?

Answer 13

48 hrs

Question 14

how does someone acquire nosocomial pnemonia?

Answer 14

inhaled own flora

Question 15

is nosocomial pneumonia resistant or sensitive to antibiotics?

Answer 15

resistant

Question 16

what are the symptoms of community acquired pneumonia?

Answer 16

fever
chest pain
purulent sputum

Question 17

what is atypical pneumonia?

Answer 17

coughing without production of sputum

Question 18

what 4 organisms cause community acquired pneumonia?

Answer 18

strep pneumoniae
Mycoplasma
Chlamydia pneumoniae
Legionella

Question 19

which mycoplasma causes pneumonia?

Answer 19

Mycoplasma pneumoniae

Question 20

how long does a Mycoplasma pneumoniae outbreak last?

Answer 20

12 - 15 months

Question 21

how often do Mycoplasma pneumoniae outbreaks occur?

Answer 21

every 4 years

Question 22

why is Mycoplasma pneumoniae difficult to gram stain?

Answer 22

no cell wall

Question 23

why cant mycoplasma be treated with some antibiotics?

Answer 23

no cell wall

Question 24

where does Mycoplasma pneumoniae live?

Answer 24

mucosa with some strains in the genital tract

Question 25

how does Mycoplasma pneumoniae cause infection?

Answer 25

attaches to receptors on epithelial cell surface, inhibits cilia movement to allow it to multiply and cause infection

Question 26

what are the symptoms of pneumonia caused by Mycoplasma pneumoniae?

Answer 26

``` Fever malaise headache sore throat rash ```

Question 27

what is the most common form of pneumonia in 5-15 year olds?

Answer 27

mycoplasma pneumoniae

Question 28

what is the treatment of mycoplasma pneumoniae?

Answer 28

erythromycin, tetracycline

Question 29

why is mycoplasma pneumoniae resistant to penicillin?

Answer 29

no cell wall

Question 30

why is mycoplasma pneumoniae hard to grow?

Answer 30

no cell wall

Question 31

how can you diagnose mycoplasma pneumoniae if you cant grow it?

Answer 31

``` Specialised media Fluorescent antibodies CFT IgM latex ELISA ```

Question 32

is Haemophilus influenzae gram positive or gram negative?

Answer 32

gram negative

Question 33

is Haemophilus influenzae a coccus or a bacillus?

Answer 33

bacillus

Question 34

what 3 things can Haemophilus influenzae cause?

Answer 34

pneumonia, meningitis, arthritis

Question 35

what are the symptoms of Haemophilus influenzae infection?

Answer 35

Low grade fever, wheezy cough which may persist for weeks May produce a rash

Question 36

what do you use to treat Haemophilus influenzae?

Answer 36

cephalosporins

Question 37

can you treat Haemophilus influenzae with penicillin?

Answer 37

no -resistant

Question 38

what plates can/can't Haemophilus influenzae grow on?

Answer 38

can- choc | can't- blood

Question 39

how can you identify Haemophilus influenzae?

Answer 39

V and X growth factors

Question 40

how can you diagnose Haemophilus influenzae?

Answer 40

PCR | latex agglutination

Question 41

what 2 types of chlamydia cause respiratory infection?

Answer 41

pneumoniae and psittaci

Question 42

what is the difference between chlamydia pneumoniae and psittaci?

Answer 42

pneumoniae causes mild pneumonia or bronchitis in adolescents and young adults. Older adults may experience more severe disease and repeated infections psittaci causes psittacosis or ornithosis after exposure to infected birds- originally parrots

Question 43

how does chlamydia cause infection?

Answer 43

Attaches to epithelial cells | Taken in to host cells and commences complicated 2 stage life cycle

Question 44

how is chlamydia spread?

Answer 44

Transmission through respiratory secretions or droplets and aerosols

Question 45

what is the incubation period for chlamydia?

Answer 45

Incubation period can be 1-4 weeks

Question 46

what are the symptoms of chlamydia pneumoniae?

Answer 46

``` fever chills headache muscle aches dry cough ```

Question 47

can you see chlamydia pneumoniae on an x-ray?

Answer 47

yes

Question 48

can you grow chlamydia?

Answer 48

no because they are intracellular

Question 49

what special set up do you need to grow chlamydia pneumoniae?

Answer 49

McCoy cells

Question 50

how can you diagnose chlamydia pneumoniae?

Answer 50

Immunofluorescence PCR Also rise in antibody titres

Question 51

how do you treat chlamydia pneumoniae?

Answer 51

tetracyclines

Question 52

what kind of legionella causes pneumonia?

Answer 52

Legionella pneumophila

Question 53

where is Legionella pneumophila found?

Answer 53

air conditioning and water cooling systems

Question 54

how is Legionella pneumophila spread?

Answer 54

aerosol transmission

Question 55

how do you diagnose Legionella pneumophila?

Answer 55

immunofluorescence

Question 56

who is affected by whooping cough?

Answer 56

children under 5

Question 57

how does whooping cough cause infection? (2 stages)

Answer 57

1. bacillus binding to mucociliary escalator - Stops it working so bacteria can multiply 2. pertussis toxin

Question 58

how is whooping cough spread?

Answer 58

respiratory droplets, coughing, sneezing

Question 59

is whooping cough gram negative or positive?

Answer 59

negative

Question 60

what shape is whooping cough?

Answer 60

short rods

Question 61

what agar does whooping cough grow on?

Answer 61

Charcoal with horse blood | Bordet- Genou

Question 62

who does pneumocystis infect?

Answer 62

immunocompromised patients

Question 63

how do you diagnose pneumocystis?

Answer 63

microscopy as doesnt grow on media | immunofluorescence

Question 64

who does Aspergillosis infect?

Answer 64

immunocompromised patients

Question 65

what is aspergilloma?

Answer 65

non-invasive aspergillus

Question 66

what is aspergillosis?

Answer 66

invasive aspergillus

Question 67

how do you diagnose aspergillus?

Answer 67

Xrays symptoms Culture from sputum on Sabouraud’s agar