My Clinical Notes

• A chronic necrotising infection of the bronchi and bronchioles leading to abnormal permanent dilation of these airways
• Clinical features include cough, fever and the production of copious amounts of purulent sputum
• It develops in association with a variety of conditions including;
  • Congenital or hereditary conditions;
    • e.g. CF, immunodeficiency states and primary ciliary dyskinesia
  • Post-infectious conditions
    • e.g. necrotising bacterial, viral or fungal pneumonia
  • Bronchial obstruction
    • e.g. tumour or foreign body
  • Other conditions
    • e.g. RA. SLE, IBD, chronic graft versus host disease

 

Aetiology and Pathogenesis

• Obstruction and infection are the major causes
• After bronchial obstruction the normal clearing mechanisms are impaired distal to the obstruction and there is inflammation of the airway
• Severe infection leads to inflammation often with necrosis and fibrosis which can dilate the airway
• Bronchiolitis obliterans occurs when the bronchioles become obliterated due to fibrosis

 

• Allergic bronchopulmonary aspergillosus (ABPA) is a hypersensitivity reaction to Aspergillus fumigatus
• It can complicate asthma and CF
• It is characterised by intense eosinophilic inflammation and the formation of mucus plugs

 

Morphology

• Usually affects the lower lobes bilaterally and is more severe in the distal bronchi and bronchioles
• The airways are dilated up to 4 times the normal size – dilations may be cylindrical, saccular or fusiform
• Generally bronchi and bronchioles are so dilated they can be followed out to the pleural surfaces
• The bronchi are filled with mucopurulent secretions
• Histology varies depending on the activity and chronicity of disease, in an active case there may be acute and chronic inflammation of the bronchi and bronchioles, desquamation of the epithelium and necrotising ulceration
• In more chronic cases fibrosis of the bronchial and bronchiolar walls leading to varying degrees of luminal obstruction
• Generally a mixed flora can be cultured from the affected bronchi with aerobes e.g. staphs and streps to anaerobes

Clinical

• Severe and persistent cough with foul smelling sputum, breathlessness, orthopneoa and haemoptysis
• There may be a fever
• Symptoms are often episodic and are precipitated by URT infections
• Obstructive ventilatory insufficiency can lead to marked dyspneoa and cyanosis
• Rare severe complications are cor pulmonale, metastic brain abscesses and amyloidosis

This entry was posted on Monday, February 18th, 2008 at 4:36 pm and is filed under Respiratory. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.