Digoxin-like substance in the serum of uremic patients before and after hemodialysis

Digoxin concentrations in serum samples were measured before and after hemodialysis of 31 uremic patients (pts) who either never took digoxin or who had not taken digoxin for at least 1 year. False positive digoxin was found in 22 of 31 patients (71%) before hemodialysis and in 14 of 31 patients (45%) after hemodialysis. The concentrations ranged from 0.1 to 0.5 nmol/L, mean value was 0.20 +/- 0.16 before hemodialysis and after hemodialysis ranged 0.1 to 0.4 nmol/L mean value was 0.11 +/- 0.14 nmol/L. The difference before and after hemodialysis is statistically significant. Some of the patients had a constant value before and after hemodialysis. None had a higher value after hemodialysis than they did before. Eight patients, who had positive serum digoxin before hemodialysis with concentrations up to 0.5 nmol/L, became negative after hemodialysis. Our results indicate that a digoxinlike substance in uremic serum could be at least partly dialyzable.