Chapter 13: Bronchiectasis and Chronic Interstitial Lung Diseases Flashcards
What is bronchiectasis?
Bronchiectasis is the permanent dilation of bronchi and bronchioles caused by destruction of smooth muscle and the supporting elastic tissue; it typically results from or is associated with chronic necrotizing infections
Is bronchiectasis primary or secondary?
Secondary (to persistent infection or obstruction caused by a variety of conditions)
What conditions most commonly predispose bronchiectasis?
- bronchial obstruction - congenital or hereditary conditions (cystic fibrosis, immunodeficiency states and primary ciliary dyskinesia) - necrotizing/suppurative pneumonia
Which two intertwined processes contribute to bronchiectasis?
Obstruction and chronic infection (either may be the initiator)
Bronchiectasis usually affects the lower lobes unilaterally/bilaterally
Bilaterally
Is in bronchiectasis the airway dilated or compressed?
Dilated (up to 4x!)
What are the clinical features of bronchiectasis?
Bronchiectasis is characterized by severe, persistent cough associated with expectoration of mucopurulent, sometimes fetid, sputum. Other common symptoms include dyspnea, rhinosinusitis, and hemoptysis. Symptoms often are episodic and are precipitated by upper-respiratory tract infections or the introduction of new pathogenic agents
What are chronic interstitial (restrictive, infiltrative) lung diseases?
Chronic interstitial diseases are a heterogeneous group of disorders characterized by bilateral, often patchy, pulmonary fibrosis mainly affecting the walls of the alveoli
True/false: Many of the entities of chronic interstitial lung disease are of unknown cause and pathogenesis
True
What is the hallmark of chronic interstitial (restrictive, infiltrative) lung diseases?
reduced compliance (stiff lungs), which in turn necessitates increased effort to breathe (dyspnea)
What are the major categories of chronic interstitial lung diseases?
- Fibrosing - Granulomatous - Eosinophilic - Smoking-related
What are other symptoms, besides reduced compliance and dyspnea of chronic interstitial lung diseases?
Damage to the alveolar epithelium and interstitial vasculature produces abnormalities in the ventilation–perfusion ratio, leading to hypoxia. Chest radiographs show small nodules, irregular lines, or “ground-glass shadows.” With progression, patients may develop respiratory failure, pulmonary hypertension, and cor pulmonale
Explain the steps that lead to fibrosis
Environmental factors (smoking/irritatns/infection) -> epithelium (might be at risk because of age/genetics) -> persistent epithelial injury/activation -> innate/adaptive immune response -> pro-fibrogenic factors -> abnormal intracellular signaling -> proliferation, collagen production -> fibrosis
What is idiopathic pulmomary fibrosis (IPF)?
Idiopathic pulmonary fibrosis (IPF) refers to a pulmonary disorder of unknown etiology that is characterized by patchy (!), progressive bilateral interstitial fibrosis
What are clinical features of IPF?
IPF usually presents with the gradual onset of a nonproductive cough and progressive dyspnea. On physical examination, most patients have characteristic “dry” or “Velcrolike” crackles during inspiration. Cyanosis, cor pulmonale, and peripheral edema may develop in later stages of the disease