Falsely low parathyroid hormone secondary to biotin interference: A case series

Objective: To present a case series on biotin interference in parathyroid hormone (PTH) level measurement.Methods: We revie. The presentation and management of patients at our institution evaluated for unexpectedly low PTH levels while taking biotin supplements i. The setting of high or normal serum calcium.Results: Two patients presented with surprising low parathyroid levels - one during preoperative evaluation for hyperparathyroidism and another during postoperative follow-up after subtotal parathyroidectomy. The patients were found to be taking 1,500 mcg and 5,000 mcg of biotin per day, respectively. The role of biotin interference was confirmed in one o. The patients when she was retested off biotin, and PTH levels responded appropriately. Biotin supplements remain as unbound molecules i. The serum, thus interfering with PTH enzyme-linked immunosorbent assay (ELISA) results and falsely depressin. The PTH level.Conclusion: Biotin supplement use has expanded ove. The years, ranging from medically endorsed therapies to home remedies. Review o. The 2 ELISA systems used at our institution demonstrates that free biotin mimic. The biotinylated antibody used i. The detection process. Screening for biotin use prior to PTH measurement and automatic biotin levels for clinically aberrant PTH levels provid. The clinician with a true PTH level - lowerin. The disease burden of untreated hyperparathyroidism while avoiding unnecessary work-ups for other processes.