Pulm VIII - Mechanical lung restriction, Interstitial lung dz, idiopathic pulmonary fibrosis, pneumoconiosis, sarcoidosis

Question 1

PFT for Restrictive DZ

Answer 1

• TLC <80% of expected (low), low FVC
• FEV1/FVC ratio = normal or increased
• DLCO helpful for distinguishing etio for Restrictive
• DEC DLCO in parenchymal dz
• NORMAL DLCO - extrathoracic cx; obesity, chest wall deformity, neuromuscl disorder

Question 2

Restrictive Pulmonary DZ

Answer 2

• inability to completely fill lungs with air
• “restricted” from fully expanding
• character by *RED lung volumes
• unlike Obstruct; assoc DEC Total Lung Capacity (TLC)

Question 3

1. Intrinsic RPD

Answer 3

• Dzs of the lung parenchyma
• Inflammation or scarring of lung tissue
• EX: Idiopathic Fibrotic DZ, Pneumoconioses, + Sarcoidosis

Question 4

2. Extrinsic RPD

Answer 4

• Extra pulmonary diseases involving chest wall, pleura, + respiratory muscles
• EX: Obesity, Myasthenia Gravis, ALS, Kyphoscoliosis

Question 5

3. Medication induced Interstitial LD

Answer 5

1. Amiodarone - classic cx

2. MTX
3. Nitrofurantoin

Question 6

Idiopathic Fibrosing Interstitial Pneumonia (formly, IPF)

Answer 6

**MC dz among patients with interstitial lung dz
- M, >50; poor prognosis
[RFs]
- Smoking, occupational exposure (stone, metal, wood, organic dusts), GERD
[Clinical Feats]
- SX: insidious dry cough, DOE, fatigue, tachypnea
- PE: Clubbing, Inspiratory rales (crackles)
[Dx]
- RED RVC, norm/elev ratio, RED DLCO, impaired 6 min walk
- CXR findings: INC in Reticular Markings (IPF, CHF)
- CT: diffuse patchy fibrosis w/ pleural based honeycombing
- can be made on characteristic presentation; lung biopsy more definitive + help r/o other cx
[TX]
Supportive Care…
- supp O2
- vaccinations (flu, pneumococcal)
- OP Pulmonary Rehab Programs
Meds;
1.Nintedanib: tyrosine kinase inhb 2.Pirfenidone: anti fibrotic*
Surgery - Lung transplantation
REQS
1. <65 yo
2. Free of substance abuse
3. BMI 20-29

Question 7

Pneumoconiosis

Answer 7

• group of interstitial lung dz, caused by inhalation + deposition of inorganic particles and mineral dusts with subsequent reaction of lung
• (3) important types
  1. Coal Worker’s
  2. Silicosis
  3. Asbestosis

Question 8

Coal Worker’s PC

Answer 8

*AKA Black Lung Dz; caused by prolonged exposure to coal dust, which is inert & cannot be removed
> inflammation, fibrosis, + sometimes, necrosis
- milder form kwn as Anthracosis
[Presentation]
- Asym in early stage
- Chronic cough, fever, + DOE; usu 10-15 yrs after exposure
- may show small, rounded nodular opacities w/ preference for upper lobes > dvp into larger opacities w/ progressive massive fibrosis
*this stage is irreversible + progresses despite cessation of exposure; prognosis is poor

Question 9

Silicosis

Answer 9

*Silica is 2nd MC element; major constituent of sand - glass, fiberoptics, porcelin
*Silicosis = spectrum of pulm dz caused by inhalation of crystalline silica
- occupations @ risk = mining, masonry, glass manufacturing, foundry work, + sandblasting
[Presentation]
- Cough, dyspnea, sometimes fever, or pleuritic CP
1. Acute
2. Chronic
3. Accelerated Silicosis - fibrosis kicks up, impairs breathing
[DX]
- H&P; work exposure
- Lab; none, but can test for TB!
- PFTs; DEC FVC & DLCO, norm ratio
- CXR/CT:
bilateral, diffuse, ground glass opacities (acute). small, innumerable rounded densities (chronic).
*Based on (3) elements:
1. HX of Silica exposure
2. Chest img consistent w.
3. DX of exclusion
~ Lung biopsy if needed
[TX]
- NO therapy; avoid further exposure & supportive care
- Steroid T: limited, acute phase
- Lung transplant: die on waiting list
[ASSOC]
#1 - TB infection!!!
- Aspergillosis
- Lung cxner
- CKD

Question 10

Asbestosis

Answer 10

*group of naturally occuring fibrous composed of hydrated magnesium silicates, constriction & insulation purposes
- pneumoc cxd by inhalational abestos fibers
- plumbers, pipefitters, electricians, insulation workers, carpenders
[presentation]
- Asym for @ least 20-30 yrs
- DOE, cough, weight loss
- Inspiratory crackles, clubbing on PE
- PFTs: RED VLC & TLC, low DLCO
- CXR: Thickened pleura & calcified pleural plaques
- CT: coarse honeycombing, hazy ground glass appearance in peripheral pleural surface
[TX]
- No proven T, avoid further exposure, supportive care, vaccinations, SMOKING CESSATION!!!
[Major Complication]
#1 - Malignant mesothelioma**

Question 11

Sarcoidosis

Answer 11

*multisystem granulomatous disorder, unk etio; characterized by presence of NON-caseating granuloma
*LNs, eyes, skin, liver, spleen, heart, NS…90% of pts have Lung involvement!!!
*young black woman & north europe w’s
[Presentation]
- Cough, dry hacking
- DOE, progressive
- Atypical chest discomfort
- Fever/nightsweats/weight loss; (DDX infxt, malignancy, lymphoma)
[DX]
- CXR: bilateral hilar adenopathy
- CT: “SARCOID GALAXY SIGN”, RT paratracheal lymphadenopathy along w/ bilateral diffuse reticular infiltrates
- ET US guided biopsy (EBUS), cervical mediastinoscopy, VATS lung biopsy
[TX]
- Close observation of asym pts
- 90% of pts are responsive to PO steroid taper over 4-6 wks