Which histological finding in pulmonary emphysema differentiates centriacinar (centrilobular) type from panacinar (panlobular) type?

• A Centriacinar: destruction limited to respiratory bronchioles (central acinus); panacinar: uniform destruction of the entire acinus including alveolar ducts and sacs ✓
• B Centriacinar: affects lower lobes; panacinar: affects upper lobes
• C Centriacinar: associated with alpha-1 antitrypsin deficiency; panacinar: associated with smoking
• D Centriacinar: shows fibrosis; panacinar: shows inflammatory infiltrates

Explanation

Centriacinar emphysema destroys the respiratory bronchioles (proximal part of the acinus) while sparing distal alveoli, predominates in the upper lobes, and is strongly associated with cigarette smoking. Panacinar emphysema involves uniform destruction of the entire acinus from respiratory bronchiole to terminal alveoli, predominates in the lower lobes, and is the pattern associated with alpha-1 antitrypsin deficiency. Recognizing upper vs. lower lobe predominance is a secondary feature; the primary distinction is acinar distribution. Neither type is primarily fibrotic.

Reference: Robbins & Cotran Pathologic Basis of Disease, 10th ed.

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Written and medically reviewed by the StethoPrep medical team.