Continuation of Over-the-Counter Biotin Supplements in the Inpatient Setting: An Unexpected Source of Laboratory Error

Background Over the past decade, use of high-dose biotin has increased significantly and can lead to erroneous results on some clinical immunoassays. In collaboration with pharmacists at our institution, we discovered that high biotin doses were being administered to inpatients as a continuation of patient-reported home biotin use. Methods This retrospective study evaluated high-dose biotin administration in 226 inpatient encounters from 2009 to 2019 and its potential impact on concurrent immunoassay testing. Results In 96% of cases, biotin was administered in the inpatient setting as a continuation of patient-reported home use. In total, 322 immunoassays capable of biotin interference were performed across 100 inpatient encounters with high-dose biotin administration. Troponin T and TSH were the most commonly performed immunoassays in this cohort. Discussion Even though less than 5% of all high-dose biotin orders at our institution are placed for inpatients, hospitalized patients are still at risk for mismanagement due to erroneous immunoassay results. Immunoassay testing susceptible to biotin interference was performed in approximately 45% of inpatient encounters with biotin administration. Laboratories utilizing biotin-susceptible, sensitive cardiac troponin assays should be particularly cautious. Pharmacokinetic data for biotin clearance is especially lacking for certain populations likely to be hospitalized, such as those with renal failure. Given that medical conditions requiring high-dose biotin therapy are extremely rare, we recommend restricting biotin dosing during inpatient encounters for all other patients.