Caused by tubercle bacilli that invade lung tissue. Skin test detects immunity developed due to previous exposure. Air is trapped in alveoli which often causes rupturing of alveolar walls. Lack of oxygen to brain causes depression, irritability, etc. Fibrous connective tissue builds up in lungs.
Breathing is impaired, and the development of cancer is common.
Women Catch Up i. Callused cells thicken to block bronchi. Cilia are lost and protection decreases. Cells with atypical nuclei appear. Tumor may grow until bronchus is blocked, lung collapses, fluid is trapped inside, and pneumonia may result.