Alpha-1 antitrypsin deficiency is a condition which predisposes to emphysema and liver disease. It is inherited in an autosomal co-dominant fashion.
Alpha-1 antitrypsin itself is a protease inhibitor produced in the liver. In the lungs this protects alveolar tissue from damage by neutrophil elastase. Its lack in the liver can result in cirrhosis.
A deficiency makes it likely COPD will develop in the third or fourth decade in smokers or fifth or sixth decade in non-smokers. The classical pattern of lung damage is panlobular emphysema in the lower lobes.
The severity of the deficiency depends on the alleles – ‘normal’ levels of alpha-1 antitrypsin occur with MM, with lower levels with SS and lower levels still with ZZ.
Management involves avoidance of cigarette smoke and possibly lung/liver transplantation in end-stage disease.
Small print gem: Panniculitis is associated with the ZZ form of alpha-1 antitrypsin deficiency. It is inflammation of fat under the skin and presents as a tender, ‘woody’ feeling area with nodules or lumps under the skin.
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