Investigation of possible interference by digoxin-like immunoreactive substances on the Architect iDigoxin CMIA in serum samples from pregnant women, and patients with liver disease, renal insufficiency, critical illness, and kidney and liver transplant.

Background: Although the possible interference of digoxin-like immunoreactive substances (DLIS) on the Architect iDigoxin chemiluminiscent microparticle immunoassay (CMIA) has been emphasized by the manufacturer, a specific study about this subject has still not been carried out.

Methods: Apparent serum digoxin concentrations were determined using the Architect iDigoxin CMIA from Abbott Laboratories in digoxin-free pregnant women (n = 50), and patients with liver disease (n = 50), renal insufficiency (n = 50), kidney (n = 25) or liver (n = 25) transplant, and critical illness (n = 50).

Results: In all of the patients included in this study, apparent serum digoxin concentrations were lower than the correspondent quantification limit (< 0.30 microg/L).

Conclusions: The Architect iDigoxin CMIA assay would be relatively free from endogenous DLIS positive interferences.