Alpha-1-antitrypsin deficiency in childhood.

alpha 1AT deficiency predisposes children to liver injury and adults to emphysema. Pi typing has clarified that the inherited deficiency is codominant. Amniocentesis is unproved as a reliable technique in detecting the homozygous deficient patient (another controversial issue). Even if this procedure were to become diagnostic, present knowledge cannot predict the clinical course of each individual born with homozygous alpha 1AT deficiency, therefore confronting the physician and parents with a moral dilemma that neither of us feels comfortable with in regard to family counseling. Presently, we can only educate the family with the current state of the art summarized in this review. The fundamental steps in evaluating a child and the involved family are outlined in Table 2. Steps 1, 2 and 5 should be readily available. Pi typing can specifically identify susceptible individuals who can be counseled concerning work habits and known toxins such as smoking and alcohol. Liver biopsy is not essential for diagnostic purposes but may prove to be prognostic concerning the child's ultimate outcome. More certain is the evidence that no infant should be explored for a bile duct lesion during the early cholestatic period because no surgical lesion will be found. Therefore, all children with infantile cholestasis should be evaluated for alpha 1AT deficiency prior to a laparotomy. Although medical therapy is only supportive at the present time, further research should eventually provide therapeutic approaches to the basic defect.