Interstitual Lung Diseases

Question 1

How are Diffuse Parenchymal Lung Diseases (DPLD) characterized?

Answer 1

• inflammation and fibrosis of pulmonary interstitium
• about 200 diseases
• about 30% of pts have a specific diagnosis, about 70% are idiopathic interstitial pneumonias

Question 2

DPLD known causes:

Answer 2

Drugs- Amiodarone, Bleomycin, Methotrexate
Conective tissues diseases- Systemic lupus erythematosis, Scleroderma
Environmental exposures- Bird Fanciers lung, farmers lung
Occupational exposures- asbestosis, silicosis, coal workers pneumoconiosis

Question 3

DPLD w/ granulomatosis:

Answer 3

• Sarcoidosis
• Wegners Granulomatosis
• Rheumatoid Arthritis

Question 4

Rare causes of DPLD:

Answer 4

• Lymphoangioleiomyomatosis (LAM)
• Pulmonary Langerhans Cell Histiocytosis X
• Esoinopilic Pneumonia

Question 5

Separating DPLD and Idiopathic interstitial pneumonia:

Answer 5

• clinical, radiologic, pathologic features

- IPF (idiopathic pulmonary fibrosis) is common and can be fatal

Question 6

Idiopathic Pulmonary Fibrosis (IPF):

Answer 6

• defined as a specific form of chronic fibrosing interstitial pneumonia that is limited to the lung and associated with the histological appearance of Usual Interstitial Pneumonia (UIP) on surgical lung biopsy
• Characterized by progressive interstitial fibrosis resulting in severe restrictive lung disease and death from respiratory failure within 5 years of diagnosis (70% mortality)

Question 7

IPF

Answer 7

• Hamman-Rich syndrome
• fibrosing alveolitis and cryptogenic fibrosing alveolitis.
• Typically occurs in individuals over 50 years old. Males are more commonly affected. No race or ethnicity predilection.
• Risk factors include smoking, environmental exposure to particulate materials, virus infections and family history (less than 5 – 10 % of cases are familial – AD with variable penetrance)

Question 8

What is the most common presenting symptom is exertional dyspnea and a nonproductive cough

Answer 8

IPF

Question 9

Diagnosing IPF:

Answer 9

Patients typically have symptoms for many months before the diagnosis is made
Some patients may have weight loss, low grade fever, fatigue
Often treated for “bronchitis”, “asthma”, “CHF”
Physical exam shows fine inspiratory crackles (Velcro rales) at the bases.
Oxygen sats may be normal early in the disease

Question 10

IPF Lab testing:

Answer 10

• Routine laboratory testing is nonspecific
• PFTs reveal a restrictive pattern with a low TLC, FEV1 and DLCO
• Chest Xray shows lower lung zone reticular opacities that progress over time
• High Resolution Computed Tomography (HRCT) is the single most important diagnostic modality showing patchy, peripheral subpleural reticular opacities and “honeycombing”

Question 11

IPF Lab testing:

Answer 11

• Routine laboratory testing is nonspecific
• PFTs reveal a restrictive pattern with a low TLC, FEV1 and DLCO
• Chest Xray shows lower lung zone reticular opacities that progress over time
• High Resolution Computed Tomography (HRCT) is the single most important diagnostic modality showing patchy, peripheral subpleural reticular opacities and “honeycombing”
• -HRCT in experienced hands, in conjunction with the appropriate clinical history, has about a 90 % specificity for IPF
• If the radiologist is not “confident” about the diagnosis then a more invasive testing modality is indicated
• Bronchoalveolar lavage (BAL) and Transbronchial lung biopsy is of limited diagnostic benefit though it may identify other causative disorders

Question 12

What is the gold standard test for IPF?

Answer 12

• Surgical lung biopsy

- usually performed with VATS technique or rarely with a thoracotomy

Question 13

If surgical biopsy is not available then the diagnosis can be made on the basis of the following:

Answer 13

see slide 34***

Question 14

If surgical biopsy is not available then the diagnosis can be made on the basis of the following:

Answer 14

see slide 34-35***

Question 15

Tx of IPF

Answer 15

• lung transplant is only proven benefit
  -There is no evidence that any drug confers either survival benefit, physiological improvement or quality of life benefit
  The current recommendation is for treatment with steroids and an immunosuppressant such as azathioprine or cyclophosphamide, oxygen if needed and pulmonary rehab
  Lung transplantation is the only therapeutic intervention of proven benefit
  Clinical drug trials - nintedanib and pirfenidone

Question 16

Sarcoid Lung Disease:

Answer 16

Sarcoidosis is multisystem disease of uncertain etiology characterized by the presence of noncaseating granulomas
The lungs are the most frequent site of organ involvement though the skin, eye, heart and brain can also be affected
Occurs in males and females of all ages but appears more common in young adults
More common and severe in African Americans

Question 17

Sarcoid Lung disease symptoms and lab tests

Answer 17

Respiratory symptoms such as dyspnea and cough are present in 50 % of patients although many patients are diagnosed by incidental imaging studies for other problems
HRCT shows characteristic lung nodules, typically 1 – 5 mm seen along bronchovasuclar bundles and subpleurally
PFTs can show a restrictive or obstructive pattern
-a biopsy must be done
Biopsy is performed by brochoscopy or by thoracoscopy/thoracotomy
Pathology reveals noncaseating granulomas which have been demonstrated to secrete serum angiotensin converting enzyme (ACE) which may be elevated in some patients

Question 18

Sarcoid Lung disease clinical course/ TX:

Answer 18

Most patients will have a stable and self-limiting illness
Some will have progressive pulmonary disease
Treatment with steroids is indicated in patients with progressive lung disease or important extrapulmonary disease with risk of end organ dysfunction though there is little definitive data to support
-lung transplant only chance for long term survival with end stage lung disease

Question 19

LYMPHANGIOLEIOMYOMATOSIS

Answer 19

Rare, idiopathic, diffuse, progressive interstitial lung disease that affects young women of child bearing age
It occurs as a sporadic disease or in association with tuberous sclerosis
Characterized by a proliferation of interstitial smooth muscles leading to cyst formation, dyspnea and pneumothorax
The thoracic duct may also be affected leading to obstruction and chylothorax

Question 20

LYMPHANGIOLEIOMYOMATOSIS cont.

Answer 20

Half of the patients may also have renal angiomyolipomas
Diagnosis is strongly suspected in a young woman with emphysema, recurrent pneumothorax or chylothorax, typical HRCT and confirmed with lung biopsy
Natural history of the disease is thought to be progressive with a median survival of 8 to 10 years after diagnosis

Question 21

LYMPHANGIOLEIOMYOMATOSIS Tx:

Answer 21

Pregnancy and supplemental estrogen accelerate the disease process
Treatment has consisted of oophorectomy, progesterone and tomoxifen
Only lung transplantation offers any hope for cure although the disease has been reported to recur in the donor lung

Question 22

Diagnosing ILD:

Answer 22

Clinical
Radiographic (CT scanning)
Bronchoscopy
Surgical Lung Biopsy (gold standard)

Question 23

Gold standard test for diagnosing ILD?

Answer 23

Surgical Lung Biopsy

Question 24

PNEUMOCONIOSES

Answer 24

An occupational lung disease caused by the inhalation of particulate particles (dust) most often in the mining and agricultural industries
Causes an inflammatory reaction in the lung leading to fibrosis and lung dysfunction
In 2013 it was responsible for over 250,000 deaths (46,000 silicosis, 24,ooo asbestosis and 25,000 due to coal worker’s pneumoconiosis)

Question 25

Different kinds of pneumoconiosis:

Answer 25

Coal Worker’s Pneumoconiosis (black lung, anthracosis) – Coal or Carbon
Asbestosis – Asbestos
Silicosis – Silica (Silicon Dioxide) is the most abundant mineral on earth.
Siderosis – Iron
Berylliosis – Beryllium
Byssinosis – Cotton

Sometimes, it may be a combination of the above.

Question 26

Dx of pneumoconiosis

Answer 26

Careful history and physical examination
Work history and exposure history
Smoking history
Family history
Work history of spouse (most important for asbestos exposure)
Remember the latent period can be long before the patient presents for treatment

Question 27

Diagnosis of pneumoconiosis (symptoms and tests):

Answer 27

Symptoms are very similar to other diffuse parenchymal lung diseases with dyspnea and cough predominating
Chest Xray is usually abnormal
CT scan of the chest may be highly suggestive of pneumoconiosis
Pulmonary Function Tests
Bronchoscopy and BAL and lung biopsy may be performed
Surgical lung biopsy is usually definitive

Question 28

Tx of pneumoconiosis:

Answer 28

Remove the causative agent.
Oxygen
Bronchodilators
Immunosuppression
Best supportive care (treat any lung infections, vaccinations up to date, monitor oxygen saturations and spirometry)
*Lung transplantation is the only real option for severely symptomatic patients

Question 29

Summary of pneumoconiosis:

Answer 29

The pneumoconioses are a diverse group of lung diseases due to occupational exposure of particulate matter, usually minerals.
The vast majority of patients will present with dyspnea and cough
A careful history and physical, CXRay and CT scan can differentiate in some cases
Treatment is to remove the offending or causative agent and “best supportive care”