Clin Chem Lab Med 2015; aop
Letter to the Editor Lucas Peltier, Catherine Massart*, Marie-Pierre Moineau, Anne Delhostal and Nathalie Roudaut
Anti-streptavidin interferences in Roche thyroid immunoassays: a case report DOI 10.1515/cclm-2015-0350 Received April 14, 2015; accepted June 10, 2015
Keywords: anti-streptavidin antibody; thyroid immuno assays; thyroid interferences.
To the Editor, Commonly, thyroid function tests (TFTs) include measurement of thyrotropin (TSH), free thyroxine (FT4) and sometimes free triiodothyronine (FT3) or thyroid autoantibodies (Ab) against thyroperoxidase (anti-TPO), thyroglobulin (anti-Tg), TSH-receptor (anti-TSHR). In the past 20 years, several reports of interferences in TFTs including non-specific binding of heterophile antibodies [1], rheumatoid factors [2], thyroid hormone autoantibodies (THAA) [3, 4] or ruthenium [5] have been published. In April 2013, a 17-year-old woman presented a secondary amenorrhea after stopping oral contraceptives. Hormonal dysfunction including TFTs was investigated. *Corresponding author: Catherine Massart, Unité d’Hormonologie, Service de Biochimie, CHU Pontchaillou, Rue H. Le Guilloux Rennes Cedex 35043, France, Phone: +33 2 99289627, Fax: +33 2 99284145, E-mail: [email protected]; Centre d’Investigation Clinique, INSERM 1414, Université Rennes 1, Rennes, France; and Groupe de Biologie Spécialisée, Société Française de Médecine Nucléaire, Centre Antoine Béclère, Paris, France Lucas Peltier: Unité d’Hormonologie, Service de Biochimie, CHU Pontchaillou, Rennes, France; and INSERM UMR 991, Iron and the Liver Team, Rennes, France Marie-Pierre Moineau: Groupe de Biologie Spécialisée, Société Française de Médecine Nucléaire, Centre Antoine Béclère, Paris, France; and Département de Biochimie et Pharmaco-Toxicologie, Hôpital de la Cavale Blanche, CHRU, Brest, France Anne Delhostal: Laboratoire d’Analyses Médicales LABAZUR, Chateaulin, France Nathalie Roudaut: Service d’Endocrinologie, Hôpital de la Cavale Blanche, CHRU, Brest, France
Initially TSH was measured on the Cobas e602® (Roche Diagnostics). The slight decrease in TSH levels (0.26 mIU/L; reference range: 0.27–4.2) led to a second TFT investigation including FT4 measurement (Table 1). The hormonal results showed a TSH result at the lower limit of the normal range (0.39 mIU/L) with an increase in FT4 (25.8 pmol/L: reference range 12–21.9). On examination, the patient had heart palpitations and insomnia. The aim of this study is to exclude or confirm the presence of a possible interference in a patient sample because thyroid hormone concentrations measured using Roche immunoassays did not seem to correlate with the clinical status of the patient. Therefore, total TFTs were explored including FT3 and thyroid autoantibodies against anti-TSHR, anti-TPO and anti-Tg. All the parameters were measured on the automated Cobas e602®. Once more, high FT4 concentration (26.7 pmol/L) was found associated with increased levels of FT3 (9.8 pmol/L; reference range 3.5–7.7), anti-TSHR (14.1 IU/L; reference range
Letter to the Editor Lucas Peltier, Catherine Massart*, Marie-Pierre Moineau, Anne Delhostal and Nathalie Roudaut
Anti-streptavidin interferences in Roche thyroid immunoassays: a case report DOI 10.1515/cclm-2015-0350 Received April 14, 2015; accepted June 10, 2015
Keywords: anti-streptavidin antibody; thyroid immuno assays; thyroid interferences.
To the Editor, Commonly, thyroid function tests (TFTs) include measurement of thyrotropin (TSH), free thyroxine (FT4) and sometimes free triiodothyronine (FT3) or thyroid autoantibodies (Ab) against thyroperoxidase (anti-TPO), thyroglobulin (anti-Tg), TSH-receptor (anti-TSHR). In the past 20 years, several reports of interferences in TFTs including non-specific binding of heterophile antibodies [1], rheumatoid factors [2], thyroid hormone autoantibodies (THAA) [3, 4] or ruthenium [5] have been published. In April 2013, a 17-year-old woman presented a secondary amenorrhea after stopping oral contraceptives. Hormonal dysfunction including TFTs was investigated. *Corresponding author: Catherine Massart, Unité d’Hormonologie, Service de Biochimie, CHU Pontchaillou, Rue H. Le Guilloux Rennes Cedex 35043, France, Phone: +33 2 99289627, Fax: +33 2 99284145, E-mail: [email protected]; Centre d’Investigation Clinique, INSERM 1414, Université Rennes 1, Rennes, France; and Groupe de Biologie Spécialisée, Société Française de Médecine Nucléaire, Centre Antoine Béclère, Paris, France Lucas Peltier: Unité d’Hormonologie, Service de Biochimie, CHU Pontchaillou, Rennes, France; and INSERM UMR 991, Iron and the Liver Team, Rennes, France Marie-Pierre Moineau: Groupe de Biologie Spécialisée, Société Française de Médecine Nucléaire, Centre Antoine Béclère, Paris, France; and Département de Biochimie et Pharmaco-Toxicologie, Hôpital de la Cavale Blanche, CHRU, Brest, France Anne Delhostal: Laboratoire d’Analyses Médicales LABAZUR, Chateaulin, France Nathalie Roudaut: Service d’Endocrinologie, Hôpital de la Cavale Blanche, CHRU, Brest, France
Initially TSH was measured on the Cobas e602® (Roche Diagnostics). The slight decrease in TSH levels (0.26 mIU/L; reference range: 0.27–4.2) led to a second TFT investigation including FT4 measurement (Table 1). The hormonal results showed a TSH result at the lower limit of the normal range (0.39 mIU/L) with an increase in FT4 (25.8 pmol/L: reference range 12–21.9). On examination, the patient had heart palpitations and insomnia. The aim of this study is to exclude or confirm the presence of a possible interference in a patient sample because thyroid hormone concentrations measured using Roche immunoassays did not seem to correlate with the clinical status of the patient. Therefore, total TFTs were explored including FT3 and thyroid autoantibodies against anti-TSHR, anti-TPO and anti-Tg. All the parameters were measured on the automated Cobas e602®. Once more, high FT4 concentration (26.7 pmol/L) was found associated with increased levels of FT3 (9.8 pmol/L; reference range 3.5–7.7), anti-TSHR (14.1 IU/L; reference range
