[Estimating concentrations of serum total digoxin and digoxin-like immunoreactive substances in patients of cardiac failure with renal insufficiency].
Measurement of serum digoxin concentration is recommended as a routine in patients undergoing digoxin therapy because its therapeutic range is narrow. The presence of a high concentration of digoxin-like immunoreactive substances(DLIS) in human serum have been reported in a number of pathophysiological conditions. DLIS which cross-react with anti-digoxin antibodies, can falsely elevate the total digoxin concentration and is troublesome in the therapeutic monitoring of digoxin. The concentrations of serum total digoxin and DLIS in twelve patients of cardiac failure with renal insufficiency were estimated after determination of free digoxin by ultrafiltration with fluorescence polarization immunoassay. In these patients, the free digoxin concentration in serum determined was 0.79 +/- 0.48 (0.46-2.10) nmol.L-1. The total digoxin determined(1.31 +/- 0.80 nmol.L-1) was significantly higher than the calculated total digoxin(1.05 +/- 0.64 nmol.L-1) (P < 0.01), suggesting the presence of elevated DLIS in serum for these patients. The calculated DLIS concentration was 0.27 +/- 0.19(0.07-0.76) nmol.L-1. The results were well consistent with that obtained by recently published method of Dasgupta et al. In conclusion, the approach presented in this paper can estimate the true serum concentrations of digoxin and DLIS in patients of chronic cardiac failure with renal insufficiency.
Li
J H
JH
Department of Clinical Pharmacology, General Hospital of Nanjing Armed Forces, Nanjing 210002.
Wu
Z G
ZG
Xu
J Q
JQ
Zhou
Y
Y
D002298:Cardenolides; D002303:Cardiac Output, Low / Q000097:blood* / Q000150:complications; D004077:Digoxin / Q000097:blood*; D016231:Fluorescence Polarization Immunoassay; D006801:Humans; D007676:Kidney Failure, Chronic / Q000097:blood* / Q000150:complications; D012503:Saponins / Q000097:blood*; D014462:Ultrafiltration
D002298:Cardenolides; D012503:Saponins; C034504:digoxin-like factors; D004077:Digoxin