Resp Path 3 - RESTRICTIVE DZ (Fibrosing Dz, Granulomatous Dz), Smoking related interstital dz, Other interstitial dz - Galbraith Flashcards
What characterizes chronic diffuse interstitial diseases?
Inflammation and pulmonary interstitial tissue fibrosis, particularly involving the alveolar walls.
What clinical and functional changes constitute restrictive lung disease due to interstitial fibrosis?
Decreased of diffusion lung capacity, volumes, and compliance without evidence of airway obstruction.
Long term sequelae of restrictive lung disease.
End stage:
Pulmonary HTN and cor pulmonale.
End stage: parenchymal destruction and scarring
What is honey-comb lung?
Indicative of end stage restrictive lung disease. Parenchymal destruction and scarring.
Histological and clinical features of chronic diffuse interstitial diseases.
(1) Fibrosing
(2) Granulomatous
Esoinophilic
(3) Smoking-related
What fibrosing disease is a disorder of unknown cause, but characterized by PROGRESSIVE PULMONARY INTERSTITIAL FIBROSIS?
Idiopathic Pulmonary Fibrosis
Postulated pathogenesis of Idiopathic Pulmonary Fibrosis
REPEATED CYCLES of epithelial activation/injury, causing abnormal “wound healing” resulting in EXCESSIVE FIBROBLAST PROLIFERATION (driven by TGF-B1).
Sources of injury to epithelium in Idiopathic Pulmonary Fibrosis (5)
Tobacco smoke Occupational irritants Viruses Persistent gastric reflux Genetic: telomerase mutations (TERT, TERC)
What three disorders have a pathologic morphologic pattern of fibrosis denoted “Unusual Interstitial Pneumonia” (UIP)?
Connective tissue disorders
Chronic hypersensitivity pneumonia
Asbestosis
Describe UIP morphology
- SUBPLEURAL AND INTERLOBULAR septal fibrotic distribution (around alveolar edges, works inward), as well as lower lobe predominance.
- PATCHY INTERSTITIAL FIBROSIS with VARIABLE AGE
- Honeycomb fibrosis/lung = due to destruction of alveolar architecture.
- NEW FIBROBLASTIC FOCI mixed with more densely fibrotic areas
Characteristics of honeycomb fibrosis
dense fibrosis and cystic spaces lined by hyperplastic type II pneumocytes (tall cells) or bronchiolar epithelium
Fibroblastic Foci are indicative of what stage of what lesion?
EARLY lesion of idiopathic pulmonary fibrosis
Clinical course of Idiopathic Pulmonary Fibrosis.
> 50yo initially presents with DOE, dry cough. Progresses to hypoxemia, cyanosis, clubbing.
Median survival of Idiopathic Pulmonary Fibrosis.
Therapy.
3 years
Lung transplant only definitive tx.
What develops as EITHER interstitial chronic inflammation OR interstitial fibrosis, NO heterogeneity.
Nonspecific interstitial Pneumonia
The 2 common histologic patterns seen in Nonspecific Interstitial Pneumonia (NSIP)
- CELLULAR»_space; Moderate chronic interstitial inflammation.
2. FIBROSING»_space; Interstitial fibrosis - more homogenous in age than UIP.
Demographic and clinical course associated with Nonspecific interstitial Pneumonia.
- Females in 50s.
- No smoking association
- Presents with dyspnea and cough.
Loose fibrous tissue balls that fill terminal bronchioles, alveolar ducts, and alveolar spaces.
Think what?
Cryptogenic Organizing Pneumonia (COP).
Masson bodies
COP presentation and treatment/recovery.
- Present with cough/dyspnea.
- Most require steroid therapy, but can recover spontaneously.
Interstitial fibrosis in COP?
No
Pulmonary involvement patterns in CT diseases (i.e. SLE, RA, scleroderma)
NSIP, UIP, vascular sclerosis, organizing pneumonia, bronchiolitis.
Better prognosis with idiopathic UIP.
What is a group of non-tumor lung diseases in a setting of INHALATION exposure to mineral dusts, inorganic and organic particles, and chemical fumes?
Pneumoconiosis
What four factors determent particle pathogenicity in pneumoconiosis?
- Particle size (**1-5 micrometers most dangerous»_space; can reach terminal alveoli)
- Particle solubility
- Level and duration of exposure/effectiveness of clearance.
- Intensity of immune response (can cause fibroses)
Two types of pneumoconiosis.
- Coal Workers’ Pneumoconiosis (CWP)
- Silicosis
- Asbestosis
Carbon dust causes…
- Anthracosis to
- CWP (w/o significant pulmonary dysfunction) to
- Complicated-CWP to
- Progressive Massive Fibrosis (PMF)
Describe anthracosis. Histo and demographic.
BLACK pigmented lesions formed by inhaled carbon that’s taken up by alveolar and interstitial MACROPHAGES. Accumulate in LYMPHATICS an lymphoid tissues.
- Seen in CWP, smokers, urban dwellers.