What is a common feature of intrapulmonary restrictive disorders?

• A. Chronic infections
• B. Granuloma formation
• C. Increased airway resistance
• D. Reduced lung volumes

Answer: (D)

Intrapulmonary restrictive disorders are characterized by a limitation in lung expansion, which results in decreased lung volumes. This means that the total capacity of the lungs to hold air is reduced, affecting both inhalation (the volume of air taken in) and exhalation (the volume of air expelled). Conditions such as pulmonary fibrosis, sarcoidosis, and interstitial lung disease exemplify intrapulmonary restrictive disorders, where lung tissue becomes stiff or less compliant, inhibiting the normal lung function and leading to decreased lung volumes.

Understanding lung volumes is crucial in diagnosing and managing respiratory conditions. In contrast to restrictive disorders, obstructive disorders, such as asthma or COPD, are associated with increased airway resistance. Therefore, the hallmark of intrapulmonary restrictive disorders is indeed the reduction in lung volumes, which is vital for differentiating these disorders from obstructive diseases.