Lower respiratory tract infections

Question 1

What groups does pneumonia occur more frequently in

Answer 1

Very old and very young

Question 2

In what % of patients with pneumonia can no cause be identified?

Answer 2

40-60

Question 3

Which nosocomial infection has the highest mortality

Answer 3

Pneumonia

Question 4

Predisposing factors for hospital acquired pneumonia?

Answer 4

Abnormal conscious state
Intubation
Ventilation
Surgery
Immunosuppresion

Question 5

What type of organisms tend to cause pneumonia

Answer 5

Gram neg

Question 6

Name 2 typical bacterial causes of community acquired pneumonia

Answer 6

• Streoptococcus pneumoniae

- Haemophilus influenzae

Question 7

Name 2 atypical bacterial causes of community acquired pneumonia

Answer 7

Mycoplasma pneumoniae

Chylamydia pneumoniae

Question 8

Signs and symptoms of typical community acquired pneumonia

Answer 8

• Sudden onset chills
• Fever
• Pleuritic chest pain
• Productive cost: sputum is thick, purulent and rusty

Question 9

How does white blood cell count differ

Answer 9

Usually very high

Question 10

What is the commonest cause of lobar pneumonia

Answer 10

Streptococcus pneumoniae

Question 11

What would gram stain of sputum show in a person with S. pneumonia

Answer 11

• Catalase neg
• Alpha haemolytic colonies
• Bile soluble
• Susceptible to optochin

Question 12

2 definitions of atypical pneumonia

Answer 12

1) Pneumonia not due to S. pneumoniae

2) Pneumonia not responding to conventional beta lactam therapy

Question 13

Describe clinical presentation of atypical pneumonia

Answer 13

• Usually insidious onset
• Not productive cough
• Fever, headache
• CHEST X-RAY MORE ABNORMAL THAT EXAM WOULD SUGGEST

Question 14

How are mycoplasma pneumoniae acquired

Answer 14

Droplet transmission

Question 15

How does mycoplasma pneumoniae pneumonia present

Answer 15

Fever
Headache
Myalgia
Earache
Dry cough
Haemolytic anaemia

Question 16

How is M. pneumoniae diagnosed

Answer 16

CXR- patchy bilateral bronchopneumonia
Antibodies produced against patients own RBCs
IgM test
PCR

Question 17

What bacteria causes Legionnaires disease?

Gram postive or negative?

Answer 17

Legionella pneumophilia

Gram negative

Question 18

How does legionella pneumophilia grow

Answer 18

On buffered charcoal yeast extract

Question 19

Clinical presentation of Legionellaires disease

Answer 19

• Confusion
• Muscle aches
• Pneumonia
• Renal failure
• (Diarrhoea)

Question 20

Is chlamydia pneumoniae an intracellular or extracellular organism

Answer 20

Intracellular

Question 21

What pathogen that causes atypical pneumonia is also implicated as copathogen in coronary artery disease/ cerebrovascular disease?

Answer 21

Chlamydia pneumoniae

Question 22

What diagnostic tools are used to identify chlamydia pneumoniae?

Answer 22

Immuno-fluoresence
Cell culture
Serology

Question 23

What causes Q fever and how is it transmited

Answer 23

Coxiella burnetti

Via infected animals/ excreta

Question 24

What can Q fever lead to

Answer 24

atypical pneumonia

Question 25

Name a cause of pneumonia in the severely immunocompromised

Answer 25

Pneomocystis

Question 26

How does classic pneymocytis present

Answer 26

Slight fever Dyspnoea Non productive cost

Question 27

What is respiratory syncytiall virus

Answer 27

Common cause of acute bronchitis in infancy which occurs in epidemic form in winter months

Question 28

Treatment of respiratory syncytial virus

Answer 28

``` Mainly supportive (humidification and oxygen) Ribavirin in severe cases ```

Question 29

What percentage of people get pleural effusion following pneumonia

Answer 29

3-5% pleural effusion

Question 30

What are the risk factors for severe pneumococcal disease

Answer 30

Children <2 Adults >65 Underlying medical conditions (splenectomy, unable to clear encapsulated bacteri, chronic cv disease)

Question 31

What organism is beta lactam inactive against

Answer 31

M.pneumoniae as this does not have a cell wall

Question 32

How is tuberculosis primarily contracted

Answer 32

Inhaling infected droplets from a cough or sneeze by infected person

Question 33

Describe myobacterium

Answer 33

- Aerobic - Non-motile - Straight or slightly curved rods - Distinctive cell wall

Question 34

What is the significance of mycobacterium having a waxy cell wall

Answer 34

``` Resistant to drying Hydrophobic Resistant to antibiotics Resustance to acid and alkali Survives in macrophages ```

Question 35

What 2 stains can be used to diagnose TB

Answer 35

Ziehl-Neelsen | Auramine-phenol

Question 36

Define multi drug resistant TB

Answer 36

Resistant to rifampicin and isoniazid