What would be the primary consequence of injury to Type II pneumocytes?

Type II pneumocytes, also known as Type II alveolar cells, are critical for maintaining the structure and function of the alveoli, the tiny air sacs in the lungs where gas exchange occurs. One of their primary roles is the secretion of pulmonary surfactant, a substance that reduces surface tension within the alveoli. This reduction in surface tension is vital for preventing alveolar collapse, or atelectasis, especially during expiration when the alveoli are at their smallest volume.

Injury to Type II pneumocytes would impair the secretion of surfactant, resulting in increased surface tension within the alveoli. When surface tension is elevated, the risk of alveolar collapse increases, leading to difficulties in breathing and reduced efficiency of gas exchange. Therefore, the primary consequence of injury to these cells would indeed be alveolar collapse, as the alveoli would struggle to remain open due to the lack of sufficient surfactant.

Since the role of Type II pneumocytes is specifically tied to maintaining alveolar stability and function through surfactant production, any damage to these cells directly compromises the integrity of the alveoli and their ability to facilitate gas exchange effectively.