Department of Pathology and Laboratory Medicine, University of Texas-Houston Medical School and Laboratory Services, Memorial-Hermann Hospital at Texas Medical Center, Houston, Texas 77030, USA.
J Clin Lab Anal. 2010;24(6):413-7. doi: 10.1002/jcla.20421.
Spironolactone, a potassium sparing diuretic metabolized to canrenone, is often used with digoxin to treat various conditions including congestive heart failure. Potassium canrenoate is a similar drug that is also metabolized to canrenone. Due to reported interference of spironolactone, potassium canrenoate, and their common metabolite canrenone with digoxin immunoassays, we investigated potential interference of these compounds with Dimension Vista Digoxin immunoassay using Flex reagent cartridge. Aliquots of a drug-free serum pool were supplemented with various amounts of spironolactone, potassium canrenoate, or canrenone and apparent digoxin values were measured using Dimension Vista digoxin assay, we observed none-detected value except when aliquots were supplemented with higher amounts of spironolactone or canrenone. Similarly, when aliquots of a serum digoxin pool (prepared by pooling specimens from patients receiving digoxin) where further supplemented with various amounts of spironolactone, potassium canrenoate, or canrenone, we observed moderately falsely elevated digoxin values only in specimens containing higher amounts of spironolactone or canrenone. We conclude that spironolactone and canrenone but not potassium canrenoate may cause modest interference with Dimension Vista digoxin assay but such interferences may not be clinically significant except with very high amounts of canrenone.
螺内酯，一种保钾利尿剂，代谢为坎利酮，常与地高辛一起用于治疗充血性心力衰竭等各种病症。坎利酮酸钾也是一种类似的药物，也代谢为坎利酮。由于报道螺内酯、坎利酮酸钾及其共同代谢产物坎利酮会干扰地高辛免疫测定，我们使用 Flex 试剂卡研究了这些化合物对 Dimension Vista 地高辛免疫测定的潜在干扰。将无药物血清池的等分试样分别补充不同量的螺内酯、坎利酮酸钾或坎利酮，并用 Dimension Vista 地高辛测定法测量表观地高辛值，除了补充高剂量的螺内酯或坎利酮时，我们观察到无检测值。同样，当进一步用不同量的螺内酯、坎利酮酸钾或坎利酮补充从接受地高辛治疗的患者中汇集的血清地高辛池的等分试样时，我们仅在含有高剂量螺内酯或坎利酮的标本中观察到中度假性升高的地高辛值。我们得出结论，螺内酯和坎利酮但不是坎利酮酸钾可能会对地高辛测定法造成适度干扰，但这种干扰可能不具有临床意义，除非坎利酮的含量非常高。
