Pulmonary Pathology Part 3 - Witrak Flashcards
What is Idiopathic Pulmonary Fibrosis?
most lethal common ILD with 70-80% mortality at 5 years post Dx = slowly progressive pulmonary fibrosis with gradually worsening dyspnea and associated non-productive cough.
- age typically >40 years, most commonly
males, and majority (70%) are smokers or
former smokers.
(Witrak says it is worse than cancer)
What do the PFT’s show in Idiopathic Pulmonary Fibrosis?
restrictive pattern with decreased TLV
and decreased FVC.
What does the CXR show in Idiopathic Pulmonary Fibrosis?
diffuse interstitial opacities.
What does the high resoluation CT show in Idiopathic Pulmonary Fibrosis?
characteristic peripheral/subpleural and bibasilar reticulonodular opacities and architectural/cystic distortion – may be sufficient for Dx (50%).
What does the histology show in Idiopathic Pulmonary Fibrosis?
usual interstitial pneumonia (UIP): patchy interstitial fibrosis alternating with normal/near-normal lung parenchyma: both old (fibrotic) and young (fibroblastic) areas of scarring – with honeycomb change.
NOTE: inflammation not a significant feature.
What is the theory of cause of Idiopathic Pulmonary Fibrosis?
abnormal alveolar healing response (fibrogenesis) to miscellaneous toxic/injurious stimuli (exogenous/endogenous) – TGF beta-related?; association with GERD
What is the clinical course of Idiopathic Pulmonary Fibrosis?
Usually relentlessly progressive with periodic acute exacerbations: can have DAD-like flare.
- typically death with hypoxemia, cyanosis,
digital clubbing - associated with
pulmonary hypertension/cor pulmonale.
- minority of patients develop bronchogenic
carcinoma: typically adenocarcinoma.
- heart failure/ischemic heart disease causes
death in 1/3 of patients.
- may co-exist with emphysema
What is the treatment for Idiopathic Pulmonary Fibrosis?
oxygen supplementation, newer medications inhibiting fibrogenesis, and lung transplant
What is the most common causes of Classic Inorganic Pneumoconioses?
Silicosis: due to inhalation of silica (silicon
dioxide) = most abundant mineral on earth.
- typically chronic lung injury from usually
long-standing (10-30 years) inhalational
exposure: esp. mining/sandblasting
workers.
- progressive respiratory insufficiency with
CXR showing multiple small (
Occupational/environmental ILD can develop from what types of inhaled organic/antigenic dusts?
hypersensitivity pneumonitis due to:
- thermophilic actinomycetes: Farmer’s
lung, grain handler’s lung, humidifier/air
conditioner lung
- bacteria (humidifier lung)
- true fungi (aspergillus)
- animal proteins (e.g. bird fancier’s lung)
What are the histological findings in Silicosis?
can see cavitary necrosis and hilar adenopathy with calcification.
- increased risk of tuberculosis.
- acute silicosis: following a massive inhalational exposure.
- histology shows fibrocellular parenchymal nodules; bronchoalveolar lavage – silica in macrophages as per energy-dispersive x-ray analysis; acute silicosis can resemble alveolar proteinosis.
How is Silicosis diagnosed?
usually a clinical one = history of exposure sufficient to cause degree of illness present, compatible chest imaging, and absence of another diagnosis to explain pulmonary findings
What is Asbestos-related lung disease due to?
- due to inhalation of naturally-occurring mineral fibers (hydrated magnesium silicates).
- USA: typically due to exposure to asbestos insulation products.
- two main asbestos fiber types: serpentine (90%:less toxic) and amphibole (more toxic).
- direct toxic effects to: pulmonary
parenchyma and pleura.
What is Asbestosis?
pulmonary interstitial lung disease beginning in lower lobes with asbestos bodies
= subtype of ferruginous body.
Benign pleural disease: parietal pleural calcified plaques (50%), pleural effusions, diffuse visceral pleural fibrosis.
Malignant pleural disease – mesothelioma: may be delayed several decades post exposure.
Lung cancer risk: increased (without smoking) and very increased (with smoking).
What are the key CXR findings in Asbestosis?
calcified pleural plaques (over dome of diaphragm or pleural lining over the rib cage)
How is Asbestosis diagnosed?
If exposure history fits symptoms and chest
imaging studies: especially calcified pleural
plaques – lung biopsy not needed.
If Bx needed for confirmation: look for
asbestos bodies and confirm with scanning
electron microscopy/x-ray analysis.
What is Coal worker’s pneumoconiosis?
- blackening of lungs = anthracosis: due to
coal dust pigment in lymphatics - formation of
small nodules/macules: esp. upper lung fields. - 90% of cases relatively benign: little to no
effect on pulmonary function. - 10% affected with progressive massive
fibrosis: likely secondary to co-existent silica
inhalation during mining process. - some association with chronic
bronchitis/emphysema.
What is hypersensitivity pneumonitis?
Immunologically mediated lung disease with mixed interstitial/alveolar features.
- due to antibody reaction to inhaled
antigen (usually organic).
- over 300 etiologies reported.
- if offending agent not removed from the
patient’s environment: can have eventual
severe pulmonary fibrosis.
What are the clinical features of hypersensitivity pneumonitis?
*Acute attacks 4-6 hours post exposure with
fever, dyspnea, cough, leukocytosis.
HRCT: characteristic mid/upper zone ground glass or nodular opacities.
PFT: can be restrictive, obstructive, or mixed patterns.
What are some common etiologies of hypersensitivity pneumonitis?
Farmer’s lung: up to 7% of farming population.
Pigeon-breeder’s lung: 6-21% of breeders.
Humidifier lung
What does the pathology show in hypersensitivity pneumonitis?
typically bronchiole-centric pattern with interstitial pneumonitis, poorly formed granulomas in 2/3; late stage disease – interstitial fibrosis with honeycombing, obliterative bronchiolitis.
How is hypersensitivity pneumonitis diagnosed?
- inhalation history
- characteristic clinical and imaging features
- BAL with lymphocytosis
- transbronchial Bx.
What is the treatment for hypersensitivity pneumonitis?
Avoid antigen exposure.
- course of corticosteroids for more severely
symptomatic patients.
- early disease reversible
What is the classical presentation of Sarcoidosis?
presenting Sx: cough, dyspnea, chest pain.
- additional Sx: fatigue, malaise, fever, weight
loss ± skin, joint, eye, other organ disease.
- majority of patients: 10-40 years old.
- USA: 3-4 times more common in African
Americans: 2% lifetime risk.
What does CXR show in Sarcoidosis?
bilateral hilar adenopathy ± reticular pulmonary opacities with mid to upper zone predominance:
-Stages I (mild) to IV (severe)
What are the pathologic features of Sarcoidosis?
non-caseating granulomas along bronchovascular lymphatics and involving alveoli - with parenchymal fibrosis in advanced cases;
hilar lymph nodes: granulomatous lymphadenitis
What does the BronchoAlveolar Lavage (BAL) show in Sarcoidosis?
increased lymphocytes with CD4/CD8 >4:1
- with typical transbronchial Bx findings = 80+%
predictive of sarcoidosis
What is the clinical course of Sarcoidosis?
- majority of patients recover with minimal to no residual symptoms (± corticosteroid Rx).
- can be incidental CXR discovery: bilateral hilar adenopathy.
- minority of patients: progressive pulmonary
fibrosis, restrictive lung function, and cor pulmonale
How is Sarcoidosis diagnosed?
By exclusion - always first rule out granulomatous infection
- may be associated with hypercalcemia (enzymatic production of active Vitamin D which leads to increased calcium absorption)
- **Biopsy to confirm.
What are the forms of Pulmonary Vascular Disease?
THROMBOEMBOLISM, pulmonary hypertension, diffuse pulmonary hemorrhage syndromes/vasculitis
Where do fat embolisms come from?
Bone fractures or orthopedic surgeries
What are the types of acquired hypercoagulability?
- immobilization/post-surgical.
- pregnancy/contraceptive hormones.
- obesity.
- cardiac disease.
- cancer*
- anti-phospholipid antibody syndromes.
- heparin-induced thrombocytopenia (HIT).
- multiple additional disease states
What are the types of congenital hypercoagulability?
Factor V Leiden, Prothrombin gene mutation, deficiencies of factors C, S or antithrombin III, fibrinolytic system deficiency.
What does the EKG show in pulmonary embolism?
may show right heart strain (acute
cor pulmonale) or electromechanical
dissociation: NSR but without pulse.
How is pulmonary hypertension defined?
mean pulmonary artery pressure > 25 mmHg at rest (normal 8-20)
What are the causes of pulmonary hypertension?
1) Chronic hypoxemic vasoconstriction: chronic lung disease (COPD/ILD), obstructive sleep apnea syndrome.
2) Acquired left heart disease: e.g. mitral stenosis: increased L atrial pressure then increased pulmonary venous pressure then increased pulmonary arterial pressure.
3) Recurrent thromboemboli
4) Primary pulmonary arterial hypertension – PCWP (pulmonary venous pressure)
What is the pathology of pulmonary hypertension?
- Arterioles/small arteries with medial hypertrophy/intimal fibrosis: some patients have significant vasospastic component
- PVOD: venule sclerosis
- R ventricular hypertrophy
- If organizing thrombi present: suggests chronic recurrent pulmonary emboli
What are the clinical features of pulmonary hypertension?
- associated underlying disease may be
dominant clinically (COPD, ILD).- cardiac exam: increased intensity of pulmonic
component of 2nd heart sound. - exertional dyspnea, lethargy, fatigue
- inability to increase cardiac output.
- RV hypertrophy with RV failure/cor
pulmonale: angina, syncope, peripheral
edema, passive hepatic congestion/abdominal
pain, elevated JVP
- cardiac exam: increased intensity of pulmonic
What are the most common causes of Pulmonary Hemorrhage resulting in hemoptysis?
Commonest causes (70%):
*Bronchogenic carcinoma
*Bronchiectasis
Bronchitis
Bacterial pneumonia
*Tuberculosis
* = can cause massive hemoptysis
Less commonly: pulmonary embolism
L ventricular failure
Mycetoma (fungus ball)
Pulmonary abscess
Rare causes of hemoptysis: miscellaneous diseases to
include: alveolar hemorrhage syndromes.
What are diffuse pulmonary hemorrhage syndrome due to?
bleeding into alveolar spaces: diffuse alveolar hemorrhage (DAH)
What are the symptoms of pulmonary hemorrhage syndrome?
usually abrupt/rapidly evolving symptom
onset with: cough, hemoptysis (may be
delayed), fever, dyspnea/hypoxemia.
What are the chest imaging findings in pulmonary hemorrhage syndrome?
CXR/CT: diffuse alveolar opacities.
What etiologies are associated with Diffuse Alveolar Hemorrhage?
Associations:
- drug/toxic injury to alveolar capillaries/wall - e.g. amiodarone, crack cocaine.
- ARDS/DAD.
- anticoagulation.
- mitral stenosis: now rare.
- pulmonary capillaritis (autoimmune).
- pulmonary infection/bone marrow
transplantation.
Mortality rates: up to 50%.
Long term risk: recurrent hemorrhage with pulmonary fibrosis.
What are some diseases that may result with Diffuse Alveolar Hemorrhage?
- ) Goodpasture’s Syndrome
- ) Wegener’s granulomatosis
- ) Systemic lupus erythematosus
- ) Idiopathic pulmonary hemosiderosis/hemorrhage
99% of lung tumors are what type?
carcinoma (ordinary lung cancer)
What are the Clinicopathologic Lung Tumor classifications?
Non-small cell carcinomas (85%):
Adenocarcinoma (40-50%) - female dominant.
- a subset of cases have a weak to no
apparent relationship to smoking.
Squamous carcinoma (20-30%).
Large cell undifferentiated carcinoma (5-15%).
Misc. non-small cell types: sarcomatoid,
pleomorphic, adenosquamous, combined
histologies.
Small cell carcinoma (15%)
