LRTI

Question 1

What are the main diagnostic techniques for LRTI’s?

Answer 1

Microscopy, culture of sputum and blood, antigen detection, PCR (NAAT - nucleic acid amplification test), serology (ELISA), latex agglutination etc.

Question 2

Describe a bronchioalveolar lavage (BAL).

Answer 2

Local airway sample collected at bronchoscopy or catheter aspirate in a ventilated patient. Can quantitate culture in CFU/ml. Less liable to contamination and so more accurate diagnosis.

Question 3

Name some common respiratory viruses.

Answer 3

IAV, IBV, PIV, adenovirus, rhinovirus, metapneumovirus, coronavirus, RSV etc.

In children: RSV, PIV3, IAV, IBV and adenovirus.

Question 4

When would antibody detection be used?

Answer 4

When it is difficult to culture or detect an organism directly. Mostly now replaced by PCR. IgM is a marker of current infection. IgG is a marker of past infection. Rising titres now used to measure response to vaccination.

Question 5

Name 3 difficult to diagnose bacterial infections.

Answer 5

Legionella pneumophila, Chlamydia psittaci, Chlamydia pneumoniae and Coxiella burnetti (Q fever).

Question 6

Which stain must be used when culturing Mycoplasma?

Answer 6

ZN stain.

Question 7

Name common bacterial causes of LRTI’s.

Answer 7

Strep pneumoniae, HiB, Moraxella catarrhalis, Mycoplasma pneumoniae and Chlamydia pneumoniae.

Question 8

What are the 5 main illnesses caused by LRTI’s in children?

Answer 8

Pneumonia (will have very > temp), bronchitis, bronchiolitis, empyema and tracheitis.

Question 9

Describe tracheitis.

Answer 9

Prolonged croup with fever and biphasic stridor. It is between croup and epiglottitis. Can be caused by Staph, Strep or augmentin use.

Question 10

Describe bronchitis.

Answer 10

Very common. Endobronchial infection that causes a loose rattly cough and vomiting. Caused by Haemophilus or Pneumococcus. Self-limiting. Caused by bacterial disturbance of mucociliary clearance. First winter bad, second better, third fine.

Question 11

What are the criteria for persistent bacteria bronchitis?

Answer 11

Wet cough, over 1 month and goes with antibiotics.

Question 12

Describe bronchiolotis.

Answer 12

Affects 30-40% of infants and is usually caused by RSV. Nasal stuffiness, poor feeding, tachypnea, crackles etc. Not recurrent and only occurs

Question 13

What is recommended for management of LRTI’s?

Answer 13

Nothing if symptoms are mild. Oral amoxicillin first line and oral macrolide second choice. Only given IV if child is vomiting.

Question 14

Can pertussis still infect those who are vaccinated?

Answer 14

Yes, just means they cannot pass it on.

Question 15

What is an empyema?

Answer 15

A complication of pneumonia in which the infection extends into the pleural space. Causes chest pain and patient will be very unwell. Use antibiotics and drain. Better prognosis in children than in adults.

Question 16

What are the symptoms of pneumonia?

Answer 16

Malaise, fever, pleuritic chest pain (inspiration), cough, purulent sputum and SOB.

Question 17

What are the clinical signs of pneumonia?

Answer 17

Pyrexia, tachypnea, central cyanosis, dullness on percussion of affected lobes, bronchial breath sounds, inspiratory crepitations and increased vocal resonance.

Question 18

Which organisms most commonly cause pneumonia?

Answer 18

Strep pneumoniae, Haemophilus influenzae or viruses.

Question 19

How is the severity of pneumonia scored?

Answer 19

CURB 65. Confusion, Blood urea over 7, RR over 30, Diastolic BP under 60 and > age 65.

0: low risk, treated at home with amoxicillin/clarithromycin/doxycycline. 1-2: hospital, amoxicillin/clarithromycin/levofloxacin. 3-5: > risk death and need for ITU, co-amoxiclav and clarithromycin/levofloxacin.

Question 20

What additional treatment can be given to penumonia patients?

Answer 20

O2, IV fluids, CPAP, intubation and ventilation.

Question 21

What are the complications of pneumonia?

Answer 21

Septicaemia, acute kidney injury, empyema, lung abscess, haemopytic anaemia and ARDS.

Question 22

What are the differential diagnoses for pneumonia?

Answer 22

LC, PE, cardiac failure and pulmonary vasculitis (Wegners granulomatosis).

Question 23

Define bronchiectasis.

Answer 23

Abnormal widening of the bronchi or their branches which causes a risk of infection.

Question 24

What are the causes of bronchiectasis?

Answer 24

Idiopathic, CF, childhood infections such as measles, immotile cilia syndrome, hypogammaglobulinaemia and allergic bronchopulmonary aspergillosis (ABPA)

Question 25

What are the symptoms and signs of bronchiectasis?

Answer 25

SYMPTOMS: chronic cough, daily copious sputum production. SIGNS: finger clubbing, coarse inspiratory crepitations on auscultation.

Question 26

Which organisms commonly cause bronchiectasis?

Answer 26

Haemophilus influenzae, S.aureus and Pseudomonas aeuriginosa.

Question 27

What are the investigations for bronchiectasis:

Answer 27

HRCT thorax, sputum culture, serum immunoglobulins, total IgE and aspergillus precipitins and CF genotyping.

Question 28

What are the treatment options available for bronchiectasis?

Answer 28

Chest physio, treatment of infections with antibiotics and may require inhaled therapy (ICS/B2 agonists).