Which condition is characterized by a decreased ability to expand the lungs due to stiff lung tissue?

The condition characterized by a decreased ability to expand the lungs due to stiff lung tissue is restrictive lung disease. This category encompasses various disorders that impede lung expansion, leading to reduced lung volumes and difficulty in inhalation. Such conditions may result from intrinsic factors, like lung fibrosis or interstitial lung disease, which directly affect the lung tissue, or from extrinsic factors, such as obesity or neuromuscular disorders, that limit chest wall movement and, consequently, lung expansion. Patients with restrictive lung disease typically have a reduced total lung capacity and may experience symptoms like shortness of breath during exertion due to the insufficient ability of the lungs to take in air.

In contrast, chronic obstructive pulmonary disease (COPD) primarily involves airway obstruction that impeded airflow during expiration, rather than a decrease in lung expansion. Asthma is characterized by reversible airway constriction due to inflammation and bronchospasm, which differs from the stiffness seen in restrictive lung diseases. Pneumonia, while it can lead to impaired lung function due to fluid or infection in the alveoli, does not primarily reflect the ongoing restriction associated with stiff lung tissue. Thus, restrictive lung disease is the most accurate term for a condition where lung expansion is significantly limited due to stiffness in lung tissue