Sarcoid

General

·       Widespread formation of non-caseating granulomas

·       3:1 female:male and 14:1 black:white predominance

·       ACE (angiotensin converting enzyme) elevated in 70%

·       Kveim skin test

·       Positive in (70%) but rarely used today

·       Lofgren Syndrome:

·       Acute bilateral hilar adenopathy, fever, erythema nodosum and arthralgia

·       Intrathoracic disease (90%)

Stage I

·       Adenopathy alone (43%)-Stage 1

·       Intrathoracic adenopathy in 80%

·       Location

·        Bilateral hilar and (R) paratracheal

·       Most common (75-90%)

·        “1-2-3 sign”, “Pawn-broker’s sign”, “Garland sign”

·       Unilateral hilar nodes rare (3-8%)

·       Egg-shell calcification hilar nodes in long-standing sarcoid

·       Rare

·       DDX: Silicosis

Stage II

·       Adenopathy and parenchymal disease (41%)-Stage 2

·       Adenopathy usually decreases as parenchymal disease increases

·       About 1/3 of patients with adenopathy develop parenchymal disease

Stage III

·       Parenchymal disease alone (30%)

·       Adenopathy does not develop subsequent to parenchymal disease

·       If adenopathy develops, think of lymphoma or TB

Patterns of lung disease

·       Reticulonodular (46%)

·       Acinar pattern (20%)

·       Larger nodules

·       “Alveolar sarcoid” (2%)

·      Coalescence of numerous interstitial granulomas

·       Air bronchograms present

·       DDX: Alveolar cell ca, alveolar proteinosis, lymphoma

Stage IV

·       End-stage lung disease-Stage 4

·       Diffuse fibrosis

·       Bronchiectasis-honeycomb lung

·       Multiple cysts

Uncommon manifestations

·       Associated with TB (13%)

·       Pleural effusion (2%)

·       Usually exudate with lymphocytic predominance

·       Cavitation of nodules (<1%)

·       Fungus ball formation in chronic sarcoid cavities (usually TB)

·       Focal pleural thickening

Uncommon manifestations

·       Bronchostenosis with lobar atelectasis

·       Pulmonary arterial hypertension

·       Cor pulmonale

·       Pneumothorax 2° chronic lung disease

Extrathoracic disease

·       Peripheral adenopathy (30%)

·       Liver

·       Hepatomegaly

·       Spleen

·        Splenomegaly

·       Bone-especially hands

·       Skin

·       Erythema nodosum

·       Lupus pernio (raised purplish nodules)

·       Muscle

·        Myopathy

·       Eyes

·       Uveitis

·       Uveoparotid fever

·       CNS

·       Granulomatous meningitis

·       Facial nerve palsy

·       Myocardium

·       Arrhythmias

·       Heart block

·       Cardiomyopathy

·       Salivary gland

·       Parotid enlargement

Prognosis

·       3/4 show complete resolution of hilar adenopathy

·       1/3 show complete resolution of parenchymal disease

·       20% have irreversible pulmonary fibrosis

Sarcoid. There is bilateral hilar (white arrows) and right paratracheal (yellow arrow) adenopathy, the classical triad of adenopathy in pulmonary sarcoid. Notice how adenopathy produces a lobulated, lumpy contour.

Sarcoid. There is bilateral hilar (red arrows) and right paratracheal (white arrow) adenopathy, again the classical triad of adenopathy in pulmonary sarcoid. Notice again how adenopathy produces a lobulated, lumpy contour.

Sarcoid. There are bilaterally enlarged hilar lymph nodes (white arrows) with a clear-space noted between the nodes and the cardiac contours.