Lung B39 Pulmonary hypertenstion, plueral lesions Flashcards
What are 5 main categories that cause pulmonary hypertension?
Primary lung disease: COPD disorders or interstitial lung disease
Recurrent pulmonary embolii
Upstream/antecedent heart disease (Mitral stenosis -> Increased Left atrial pressure -> increased pulm venous pressure)
Congenital Left to Right shunts
Primary idiopathic pulmonary hypertension
What signalling pathway is often altered in familial primary pulmonary hypertension?
The BMP2R of the TGF-beta pathway.
It causes excessive proliferation of pulmonary vascular smooth muscle.
What signalling pathway is often altered in sporadic cases of primary pulmonary hypertension?
The Serotonin transporter.
Increases serotonin export by smooth muscles and increased vascular smooth muscle proliferation.
What are the common characteristic vascular features of Primary and Secondary Pulmonary Hypertension?
What are their distinctive features?
In both forms:
- Large elastic arteries: atherosclerotic plaques
- In medium arteries: proliferation of smooth muscle cells -> intma and media thickening.
- small arterioles: intima, media theckening, reduplication of both elastic membranes, narrowed lumen.
In Primary (idiopathic) pulm. hyp.
- Plexiform lesions develop in chronic stage, which are a hallmark.
- Hugely thickened walls of small arterioles with multiple reduplications of membrane, and multiple lumens.
What is the usual onset and prognosis of primary pulmonary hypertension?
It is usually diagnosed in young adults, more common in women.
Diagnosed because of dyspnea, fatigue, and fainting.
Leads to respiratory insufficiency and decompensated cor pulmonale in 2-5 years and is fatal without lung transplant.
Mechanisms pulm hypertension causes respiratory insuff:
- Edema of lung
- Endothelial injury -> micro thrombii -> thrombotic pulmonary arteriopathy
- Diffuse pulmonary endothelial injury -> ARDS
What are the COPD causes of secondary pulmonary hypertension?
COPDs
- Emphysema
- Brochiectasis
- Chronic Bronchitis
What are the classes of pulmonary interstitial disease that cause secondary hypertension?
What are some specific examples?
- Fibrosing
- Granulomatous
- Eosinophilic
- Smoking-Related
Fibrosing
- Specific Pneumonias
- Non-specific Interstitial Pneumonia (chroinc bilateral lung disease of unkown cause. that specifically causes septal/stroma fibrosis, but to a lower degree than Idiopathic Pulm Fibrosis, and there is temproal homogeneity in NSIP, whereas in Idopatich pumlonary fibrosis aka Usual Intserstiail Pneumonia there is temporoal homogeneity of the lesions-the patches of fibrosis are not all at the same stage)
- Cryptogenic Organizing Pneumonia (unknown cause, previously called Bronchiolitis Obliterans Organizing Pneumonia, the alvioli and respiratory bronchioles get filled with inflammatory cellular plugs, but causing agent is unseen/unknown. Similar to organizing pneumonias of known cause that fill the alvioli.
- Pneumoconioses
- Idiopathic pulmonary fibrosis
- Organizing/Consolidated stage of Diffuse Alveolar Damage (post ARDS).
Granulomatous:
- Sarcoidosis
- Hypersensitivity pneumonitis- aka Allergic Alveolitis aka Farmer’s lung like bronchial asthma, but instead of the allergen affecting the bronchii, it causes inflammation and damage at the alveoli. It causes a restrictive type disease. It is common due to allergies to mold and moldy grains.
Eosinophilic:
- Loeffler syndrome
- Drug allergy related
- Idiopathic chronic eosinphilic pneumonia
Smoking related
- Desquamated interstitial pneumonia
- Respiratory bronchiolitis
What are the causes of Fibrosing Interstitial Lung disease?
Fibrosing
- Specific Pneumonias
- Non-specific Interstitial Pneumonia (chroinc bilateral lung disease of unkown cause. that specifically causes septal/stroma fibrosis, but to a lower degree than Idiopathic Pulm Fibrosis, and there is temproal homogeneity in NSIP, whereas in IPF the patches of fibrosis are not all at the same stage)
- Cryptogenic Organizing Pneumonia (unknown cause, previously called Bronchiolitis Obliterans Organizing Pneumonia, the alvioli and respiratory bronchioles get filled with inflammatory cellular plugs, but causing agent is unseen/unknown. Similar to organizing pneumonias of known cause that fill the alvioli.
- Pneumoconioses
- Idiopathic pulmonary fibrosis
- Organizing/Consolidated stage of Diffuse Alveolar Damage (post ARDS).
What are the causes of Granulomatous Interstitial Lung Disease?
-
Sarcoidosis:
- Multi-organ, idiopathic disease. Non-caseating granulomas. Core is compact, concentric epetheloid macrophages, with a rim of T cells, and some giant cells, and a outer rim of fibroblasts.
- The cellular granulomas become acellular hyalinized collagenous scars chronically.
- Schaumann bodies: Laminated calicified concretions
- Asteroid bodies: Stellate inclusions inside the giant cells
- Bronchoalveolar washing/lavage will contain CD4+ cells in the fluid.
- Hypersensitivity pneumonitis- aka Allergic Alveolitis aka Farmer’s lung. Like bronchial asthma, but instead of the allergen affecting the bronchii, it causes inflammation and damage at the alveoli. It causes a restrictive type disease. It is common due to allergies to mold and moldy grains.
What does sarcoidosis cause outside of the lung?
The lungs are involved in 90% of cases at some point
Hilar and paratracheal lymph node enlargement in 75-90%
Skin lesions, typically erythema nodosum, on the legs in 25%
Eye and Lacrimal gland inflammation in 25-50% Which can eventually lead to glaucomas, eye dryness like sicca syndrome, and blindness
Parotitis, with painful inflammation of the parotid glands.
Splenic Granulomas in 75% but only causes noticeable splenomegaly in 10% of cases
Hepatic Granulomas in 1/3 of cases these will cause hepatomegaly or disrupt liver function.
Bone marrow granulomas/fibrosis is very common, but not usually clinically severe.
Hypercalcemia due to excessive Vitamin D production by the excessive granulomatous macrophages
What are the characteristics and causes of Eosinophilic Interstitial Lung Disease?
Eosinophil infiltration and/due to elevated levels of IL-5 in the alveoli
These disorders are immunologic disorders but their specific causes are not understood.
-
Acute eosinophilic pneumonia with respiratory failure
- Rapid onset fever, dyspnea, hypoxia, and diffuse lung infiltrate on x-ray
- bronchoalveolar lavage has >25% eosinophils
- Good response to corticosteroids
-
Loeffler syndrome aka Simple pulmonary eosinophilia
- transient eosinophilic lung lesions
- blood eosinophilia
- mostly innocuous condition
- thickened alveolar septa with eosinophils and a few giant cells
-
Secondary eosinophilia
- caused by asthma,
- drug allergies
- some types of vasculitis
-
Idiopathic chronic eosinophilic pneumonia
- aggregated lymphocytes and eosinophils
- in the septa
- in the alveoli
- fever, night sweating
- dyspnea
- diagnosis of exclusion
What are the characteristics of Smoking-Related Interstitial Diseases of the lung?
Aside from the obstructive diseases it causes (emphysema and chronic bronchitis), it causes restrictive diseases as well.
Desquamative Interstitial Pneumonia (DIP)
- Lots of Macrophages in the alveoli, filled with brown pigment (not hemosiderin though), called smoker’s macrophages
- Minimal thickening of the septa, and mild interstitial fibrosis.
Respiratory bronchiolitis
- Just like DIP, with the smoker’s macrophages, but instead of being in the alveoli, they are inside of the respiratory bronchioles mostly
- mild peribronchiolar fibrosis.
- Dyspnea, dry cough
What are the Primary Pleural Lesions?
What are some Secondary Pleural Lesions?
Primary pleural lesions are much less common than secondary
Primary lesions:
- Primary intrapleural bacterial infections - exudative, purulent, cellular fluid
- Primary pleural neoplasm: only one, Malignant mesothelioma
Secondary lesions
-
Pneumothorax -
- Spontaneous due to ruptured bullae, paraseptal emphysema.
- Penetrating injuries
- Rib fractures
- Lung absecesses
- Tuberculosis
- Carcinomas penetrating pleura
-
Hemothorax
- __Just blood, (not bloody effusion)
- Due to ruptured intrathoracic aortic aneurysm.
- Almost 100% fatal, very rapidly
- Hemothorax blood clots in the pleural cavity, while bloody hydrothorax/effusion does not
-
Chylothorax
- Pleural collection of lymphatic fluid, milky and contains lipids
- It is usually only a small amount
- is very significant finding,
- because it means there is obstrucion of a major lymph duct
- strongly indicates an intrathoracic cancer.
What can cause Plueral Effusions?
What are the various types?
Pleural effusions can be caused by primary or secondary pleural lesions, and can be transudates or exudates
Transudates (<2.9mg/dL protein)
- Congestive heart failure is the main cause
Exudates
- Primary viral or bacterial plueritis
- Cancers: Lung cancer, metastatic pleural cancer, or primary mesothelioma all cause exudate effusions.
- They often cause bloody effusions
- Pulmonary infarcts
- SLE, Rheumatoid Arthritis uncommon causes
- Uremia also uncommonly causes it.
What are the causes of pneumothorax? (6)
What are its potential consequences?
Causes
- Spontaneous due to ruptured bullae, paraseptal emphysema.
- Penetrating injuries
- Rib fractures
- Lung absecesses
- Tuberculosis
- Carcinomas penetrating pleura
Consequences
- Tension pneumothorax, shifts mediastinum to opposite side, causes large increase in pulmonary blood pressure
- Acute cor pulmonale.
If it is not resolved for a long period:
- Severe lung scarring preculding any possible re-expansion
- Serous hydrothorax.
- High vulnerability to infection once collapsed
- Leading to empyema and pyothorax/empyema
