1. A new syndrome, idiopathic familial dysproteinemia, is described in 4 adult members of one generation, in 2 of their paternal uncles and in 4 members of the second generation. The syndrome is characterized by hypoproteinemia and/or abnormalities in the electrophoretic patterns of the blood plasma (dysproteinemia). These are accompanied in the adult by peripheral vascular changes (ulcers of the legs in the men, low oscillometric indices in the women) and edema. There are also malformations of the thoracic cage and of the occipital hair distribution in some of the cases.
2. The idiopathic nature of the disease was ascertained in some of the patients by study of the nutritional history, of the renal, hepatic and adrenal functions, and of the response to a high-protein diet under controlled conditions.
3. In one case detailed studies of the mechanisms of plasma protein regulation resulted in findings that indicate a disturbance in the production of certain protein components. The disappearance rate of injected albumin and the rate of replacement of acutely withdrawn plasma protein were normal.
4. The clinical and physio-pathologic significance of this syndrome and the possible role of genetic factors are discussed.
ACKNOWLEDGEMENTS We wish to acknowledge the courtesy of Dr. E. Shorr and Dr. E. A. Burkhardt, who referred to us the first patient of this group. Several members of the staff of Memorial Cancer Center have helped in this study. The authors wish to thank Drs. E. McCabe and J. B. Trunnell for assistance in the clinical management of the patients; Dr. Aurelia Potor, for performing the renal and adrenal function studies; Dr. N. F. Young, who supervised laboratory procedures; Dr. H. J. Tagnon, who performed the liver function tests, assisted by Miss P. Nichols; Dr. C. G. Child, III, for performing the biopsies; Dr. S. Spitz, for the pathological interpretations and Dr. E. C. Reifenstein, Jr., for advice in preparing the graphs and manuscript.