رجل عمره ٣٨ سنة غير مدخن، يشتكي ضيق نفس متزايد منذ سنة. الأشعة المقطعية تظهر انتفاخاً رئوياً في القواعد السفلى، وأخوه الأكبر عنده تليف كبد بدون سبب واضح. التشبع ٩٣٪. أي فحص قد يطلبه الطبيب؟

A 38-year-old non-smoker has had increasing breathlessness for a year. CT shows lower-lobe emphysema, and his older brother has unexplained cirrhosis. SpO2 93%. Which test might the doctor order?

1. Sweat chloride test
2. Alpha-1 antitrypsin level
3. Morning cortisol
4. Iron studies and ferritin alone

Answer: B) Alpha-1 antitrypsin level. Inherited alpha-1 antitrypsin deficiency causes early basal emphysema and liver disease, even in non-smokers. The level is measured, smoking avoided and relatives screened.