Pathology of respiratory tract infections

Question 1

Define the mechanisms of defence in the respiratory system.

Answer 1

General immune system- humeral and cellular
Respiratory tract secretions
Upper respiratory tract as a filter
macropgae- mucociliary escalator system

Question 2

Describe the pathogenesis of bronchopneumonia and lobar pneumonia and the complications and consequences of lower respiratory tract infection.

Answer 2

Bronchopneumonia- bacterial infection that leads to acute inflammation, Pus and lots of neutrophils fill alveolar
lobar pneumonia- infection occurs in a whole lobe

Question 3

Describe the clinical features of acute bronchitis, pneumonia, and be aware of bronchiectasis, lung abscess and empyema.

Answer 3

bronchiectasis- dilation of bronchi due to bronchial obstruction, recurrent infections, lung parenchymal destruction. Can present as a cough, haemoptysis,

Question 4

be aware of causes of recurrent pneumonia.

Answer 4

if there is a tumour or foreign body, cystic fibrosis or COPD, immunocompromised, pulmonary damage

Question 5

Understand the physiological changes to pulmonary gas exchange in respiratory tract infections.

Answer 5

A reduction in the ratio of ventilation and perfusion and decrease in membrane surface area leading to hypoexemia

Question 6

Complications of pneumonia

Answer 6

Pleurisy, pleural effusion and empyema, lung abscess, bronchiectasis

Question 7

aspiration pneumonia

Answer 7

when food is breathed into the lungs instead of swallowing. vomiting, oesophageal lesion, neuromuscular disorders

Question 8

what does bronchopneumonia look like on a radiograph

Answer 8

bilateral basaal patchy opacification, relating to the focal nature of the consolidation

Question 9

what are opportunistic infections

Answer 9

have a low pathocenicity infections by organism not normally capable of producing disease in patents with intact lung defences