[DOWNLOAD] "Comparable Effects of DIGIBIND and Digifab in Thirteen Digoxin Immunoassays (Technical Briefs)" by Clinical Chemistry " Book PDF Kindle ePub Free
eBook details
- Title: Comparable Effects of DIGIBIND and Digifab in Thirteen Digoxin Immunoassays (Technical Briefs)
- Author : Clinical Chemistry
- Release Date : January 01, 2002
- Genre: Chemistry,Books,Science & Nature,
- Pages : * pages
- Size : 175 KB
Description
Digoxin is widely prescribed for the treatment of cardiac conditions (1). Because of its narrow therapeutic range, digoxin-related toxicity resulting from acute or chronic overdose is common. Metabolites of digoxin as well as related compounds, including digitoxin, tanshinones, bufandienolide, and oleander, can contribute to or independently produce digoxin toxicity (2,3). Digoxin toxicity can be rapidly and safely reversed by administration of anti-dioxin immune fragments (Fab) such as DIGIBIND [R], which has been available in the US since 1986. Therapeutic Fab products act by binding digoxin with high affinity ([10.sup.9]-[10.sup.10] L/mol), favoring movement of digoxin out of tissue and thus promoting elimination. Factors that impact dosing with Fab products include known or suspected digoxin load, patient weight and history, and renal function (4-7). Monitoring the free digoxin concentration after Fab administration may help ensure appropriate dosing, prevent deadly recrudescent toxicity, and determine when digoxin therapy should be resumed (8-10). Monitoring free digoxin in serum is challenged by the positive interference that has been extensively described with DIGIBIND, which interferes with immunoassays by competing with assay capture antibodies. The degree of interference depends on incubation times, washing steps, and the affinity of capture antibody for bound vs free digoxin (11-13). Consequently, monitoring of free digoxin in ultrafiltrates is a popular strategy for managing DIGIBIND-treated patients. Although ultrafiltration eliminates interference produced by large molecules, such as endogenous digoxin-like immunoreactive factors (DLIFs) and DIGIBIND, it does not eliminate interferences produced by small molecules known to interfere with digoxin immunoassays, such as spironolactone (14). In addition, ultrafiltration methods are not standardized, may require matrix-specific calibration, add expense and manual manipulation, and lengthen turnaround time (8,15,16).