Serum alpha1-antitrypsin level and phenotype associated with familial moyamoya disease.

Background: Obstructive vascular lesions at the terminal portion of the internal carotid arteries are thought to be the primary and essential lesions in moyamoya disease. The etiology remains unknown. To detect possible mediators of the thickened intima of moyamoya disease, we measured serum alpha-1-antitrypsin (alpha1-AT) levels and characterized the phenotype of patients with familial moyamoya disease.

Patients And Methods: Fifty-six individuals were examined, including 29 patients with moyamoya disease from 14 families. Serum alpha1-AT levels were analyzed by electroimmunoassay and genomic phenotype by isoelectric focusing.

Results: All individuals had a normal alpha1-AT phenotype. The average serum alpha1-AT level in moyamoya disease patients was significantly higher than that of normal individuals, although both were within the normal range.

Conclusions: These findings suggest that serum alpha1-AT level may be a marker, rather than an etiologic factor, indicating the progression of moyamoya disease.