Serum Proteins, Amyloid and Alzheimer's Disease*

A bstract Serum protein analysis in 60 patients with histologically confirmed Alzheimer's disease (Group A) and in 60 others with clinical dementia and radiographic evidence of diffuse cerebral atrophy compatible with Alzheimer's disease (Group B) revealed a decrease in albumin and an increase in alpha‐1 antitrypsin, alpha‐2 macroglobulin and haptoglobin fractions. These abnormalities occurred in 66 per cent of these two groups, but in only 13 per cent of a third group of patients with dementia of the non‐Alzheimer type. In addition, the highest values for alpha‐2 macroglobulin were found in Groups A and B. The possible relationships of these findings to amyloidosis of the central nervous system is discussed. The significance of these data may lie in their value as an aid in making the diagnosis of Alzheimer's disease in vivo, in the absence of a brain biopsy. Further study is needed to confirm these observations.