Granulomatous lung disease

Question 1

Granuloma formation

Answer 1

• Compact aggregates of epithelioid cells to confine pathogens
• Form in response to TNFa causing macrophages to differentiate into epithelioid cells
• Epithelioid cells then fuse to form giant cells which may have foreign body inclusions
• Some granulomas will undergo necrosis (TB-> caseous necrosis) and some do not
• Granulomas form from Th1 responses, whereas Th2 responses cause fibrosis

Question 2

Causes of lung granuloma diseases

Answer 2

• Inhaled antigens: coccidiomycosis, TB, beryllium (non necrotizing)
• Drugs: methotrexate, dilantin, talc, bleomycin
• Sarcoidosis (non necrotizing, indistinguishable from beryllium), other autoimmune

Question 3

Hx for granulomatous lung disease

Answer 3

• Travel: bakersfield associated w/ coccidiomycosis
• Occupation: farms usually associated w/ fungi and/or hypersensitivity
• Pigeons: hypersensitivity

Question 4

Sarcoidosis

Answer 4

• Multisystem granulomatous disease w/ no known etiology
• Lofgren syndrome: arthritis, erythema nodosum, bilateral hilar adenopathy
• Heerfordt’s syndrome: uveitis, parotid gland inflammation, +/- facial nerve involvement
• ACE levels may be elevated, there will be hypercalcuria and hypercalcemia

Question 5

Radiographic stages of sarcoidosis

Answer 5

• Stage 1: bilateral hilar adenopathy, mediastinal adenopathy
• Stage 2: adenopathy and parenchymal lung disease
• Stage 3: parenchymal lung disease only
• Stage 4: fibrosis and cystic changes
• Bilateral hilar adenopathy most common finding
• Upper and mid lung shows coarse reticular and cystic changes and volume loss, upward displacement of the hila and main bronchi resulting from fibrosis

Question 6

Rx of sarcoidosis

Answer 6

• Steroids and immunosuppression
• Common spontaneous remission
• Overall good prognosis
• Relapses occur

Question 7

Hypersensitivity pneumonitis (HP)

Answer 7

• Acute: responds to steroids
• Sx include cough, fever, chest tightness, malaise
• Radiography: diffuse nodular changes
• Chronic: progressive dyspnea and weight loss
• Radiography: upper lobe fibrosis, reticular infiltrates, honeycombing

Question 8

Dx of HP

Answer 8

• Immunoprecipitation of IgG toward the Ag
• Histopathology, radiography
• Exposure, occupation, PIGEONS

Question 9

Chronic beryllium disease (berylliosis)

Answer 9

• Disease is indistinguishable from sarcoidosis, thus occupational Hx is key
• Dx made w/ positive beryllium lymphocyte proliferation test
• Steroids are the Rx
• Seen in miners, aerospace engineers, manufacturers of light bulbs

Question 10

ANCA-associated granulomatous vasculitis

Answer 10

• Granulomatosis polyangiitis (GPA AKA wegener’s): granlumatous inflammation w/ no etiology
• Involves URT (sinusitis, saddle nose, epistaxis), lungs (alveolar hemorrhage and hemoptysis), and kidneys (GN and hematuria)
• Dx requires biopsy, c-ANCA should be present but negative result doesn’t rule out GPA
• Immunosuppression and steroids are Rx