Skin Findings In Pulmonary Disease

Differentiate histologic findings: sarcoidosis vs tuberculosis in skin

Sarcoidosis shows non‑caseating granulomas without necrosis. TB has caseating

Classic skin finding of sarcoidosis involving the nose and ears

Lupus pernio.

Classic sarcoidosis-associated panniculitis(inflammation of subcutaneous fat in skin)

Erythema nodosum.

Cutaneous sarcoidosis lesion that look like ringworm without scale

Annular sarcoid plaques.

Why do annular sarcoid plaques lack scale?

The process is dermal, not epidermal, so no scale is produced.

What systemic evaluations are needed for suspected sarcoidosis with skin lesions?

Ophthalmology for uveitis

What is erythema nodosum?

Tender inflammatory panniculitis of subcutaneous fat causing painful nodules on anterior legs.

What syndrome includes erythema nodosum + fever + hilar adenopathy + uveitis?

Lofgren syndrome.

Cutaneous TB histology

Caseating granulomas with central necrosis and mixed inflammatory infiltrate.

Cutaneous TB lesion with violaceous plaque and scale

Lupus vulgaris.

Cutaneous TB from direct extension of infected lymph node

Scrofuloderma.

Cutaneous TB from direct inoculation

Warty TB lesion at sites of trauma.

Why is erythema nodosum associated with TB?

Immune reaction to TB antigens

Classic skin findings associated with tobacco use

Nicotine staining, premature wrinkles, impaired wound healing, cyanosis in chronic bronchitis, digital clubbing.

Why does smoking cause premature wrinkles?

Nicotine-induced vasoconstriction and toxin-induced collagen breakdown.

Why does chronic bronchitis cause cyanosis?

Chronic hypercapnia leads to deoxygenated hemoglobin and bluish skin tone.

What causes nicotine staining?

Chronic exposure to tobacco smoke causing yellow‑brown discoloration of nails and fingers.

What is digital clubbing?

Bulbous enlargement of distal digits with increased nail‑fold angle

Cutaneous manifestation: systemic sclerosis—puffy fingers

Early diffuse swelling of digits before skin tightening.

Cutaneous manifestation: systemic sclerosis—sclerodactyly

Taut, shiny skin over fingers causing flexion contractures.

Cutaneous manifestation: systemic sclerosis—Raynaud’s phenomenon

Vasospastic episodes causing white/blue painful digits with possible fingertip ulcers.

Cutaneous manifestation: systemic sclerosis—telangiectasias

Blanching red macules on face, chest, palms.

Cutaneous manifestation: systemic sclerosis—salt and pepper skin

Mixed hyperpigmentation and depigmentation with perifollicular sparing.

Which pulmonary disease is associated with clubbing?

Chronic hypoxic lung diseases including lung cancer, interstitial lung disease, bronchiectasis.

Which pulmonary disease is associated with lupus pernio?

Sarcoidosis with sinus and lung involvement.

Which pulmonary disease is associated with erythema nodosum?

Sarcoidosis or tuberculosis.

Why does systemic sclerosis cause tight facial skin?

Excess collagen deposition causing dermal fibrosis.

What skin finding suggests chronic hypoxia?

Digital clubbing.

What skin finding suggests panniculitis?

Tender erythematous nodules on anterior legs (erythema nodosum).

What skin finding suggests granulomatous disease?

Annular plaques without scale (sarcoidosis) or violaceous plaques with scale (cutaneous TB).