Orthostatic hypotension as a clue to primary systemic amyloidosis.

Methods We reviewed the records of 138 patients with primary systemic amyloidosis seen at the Mayo Clinic from 1935 through 1964. In all instances, the presence of amyloidosis was proved by tissue biopsy or postmortem examination. The criteria for the diagnosis of orthostatic hypotension included a decrease in the standing blood pressure from the recumbent blood pressure of 30 mm Hg systolic and 20 mm Hg diastolic and the presence of light-headedness or syncope. Our patients were not taking drugs associated with hypotension, had not had surgical sympathectomy, and had no known diabetes mellitus or any other conditions reported to cause orthostatic hypotension. Amyloidosis was considered to be the cause of the orthostatic hypotension in all cases. Results (Table 1) Eleven of the 138 patients with primary systemic amyloidosis fulfill the criteria of orthostatic hypotension and constitute the material for this report. In addition, 26 other patients had systolic blood pressures of less than 100 mm Hg, but either there was no evidence of orthostatic hypotension or the information was insufficient to make an unequivocal diagnosis of orthostatic hypotension. Nine of the 11 patients were males,