This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Genetic and genetic disorders, Subject name: Pediatrics
Alpha -1 antitrypsin deficiency presents as ? 
Select and explain. 
A. Emphysema, B. Bronchitectasis, C. Empyema, D. Bronchogenic carcinoma
A: Emphysema
Answer: A: Emphysema 
Explanation: Alpha-1 antitrypsin deficiency-associated lung disease is characterized by progressive degenerative and destructive changes in the lungs (emphysema, commonly of the panacinar type). Emphysema is a chronic, usually slowly progressive illness, which most commonly causes shoness of breath. Other symptoms may include chronic cough, phlegm production, and wheezing. Emphysema is caused due to alpha 1 antitrypsin deficiency. Reference: GHAI Essential pediatrics, 8th edition