In cases where simultaneous treatment with aldosterone inhibitors is reported or known, ultrafiltration of the sample can only partly remove the inhibition and does not lead to a correct result.
Another clinically important finding of this study is the negative interference from compounds other than aldosterone inhibitors. Despite the fact that most immunoassays routinely used to measure digoxin have reasonably low cross-reactivities with the known physiologic hormones (<1%) (2), positive interference has been reported with therapeutically given steroids such as hydrocortisone (33), prednisolone, and other synthetic steroids (34).
* Interference from aldosterone inhibitors is a potential problem in an alarmingly high number of patients, in particular intensive care patients, and is not confined to single, difficult cases (38)
* Low cardiologic doses of aldosterone inhibitors produce limited inhibition only
Assessment of aldosterone inhibitors on digoxin immunoassay performance [Abstract].