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Background: Measurement of antithyroglobulin antibodies (TgAb) is important in patients with differentiated thyroid carcinoma (DTC) with total thyroidectomy. These patients are monitored based on serum thyroglobulin (Tg) levels. TgAb is known to interfere with the measurement of Tg by immunoassay. This study evaluates a new methodology for the measurement of TgAb Alinity Abbott® and the concordance with other methods (first and second generation Advia Centaur Systems Siemens® and Phadia 250 Thermofisher®)., Methods: The technical characteristics of Alinity TgAb measurement methodology were analysed, with imprecision and repeatable studies. In order to assess concordance, a minimum of 69 and a maximum of 76 samples from patients with DTC and total thyroidectomy were processed in parallel by several TgAb measurement methodologies. Agreement rates were determined using kappa statistics. The correlation between the four methods was examined pairwise using McNemar test analysis., Results: The coefficients of variation (standard deviation as a percentage of the mean % CV) for the Alinity Abbott kit reagent TgAb were within 10% included the functional sensitivity. On the other hand, the concordance analysis with the kappa index concluded substantial agreement. The McNemar test showed a significant difference between Alinity versus Centaur second generation (difference 8.33%, CI 95% 0.68-8.33, p = .0313)., Conclusion: The new methodology for the measurement of TgAb meets the imprecision standards while presenting an adequate concordance agreement with other methodologies available in laboratories. It is important to define the functional sensitivity when reporting results so that they are as reliable as possible.

Background and Purpose: To analyse the causes of hyperprolactinaemia in patients with symptoms compatible with hyperprolactinaemia evaluated in a primary care setting., Patients and Methods: A retrospective study of all patients tested for serum prolactin levels between 2019 and 2020 in 20 primary care centres at the Hospital Ramón y Cajal in Madrid. Hyperprolactinaemia is defined as a serum prolactin>19.4ng/ml in men and >26.5ng/ml in women. Aetiology is grouped into physiological (pregnancy, lactation, inadequate venipuncture, macroprolactinaemia), pharmacological, pathological (hypothalamic and/or pituitary diseases, chronic renal failure, primary hypothyroidism), and idiopathic., Results: In 1630 patients tested for serum prolactin, 30.7% (n=501) had hyperprolactinaemia. Of these 501 patients, 89.6% were females. 149 patients were referred to the Endocrinology Department and 164 to the Gynaecology Department. Aetiological diagnosis of hyperprolactinaemia was achieved in 411 out of 501 cases. The most frequent cause of hyperprolactinaemia was pharmacological, in 39.1%. The second more frequent cause was idiopathic (29%) and less common were inadequate venipuncture extraction (13.4%), tumour (8.5%) and macroprolactinaemia (3.9%). Patients with tumoural hyperprolactinaemia presented higher serum prolactin levels (87.0±80.19 vs 49.7±39.62ng/ml, P=0.010). In addition, symptoms, such as galactorrhoea (33.3% vs 16.5%, P=0.018), and headache (25.7% vs 13.3%, P=0.045), were more frequent than in patients of the other aetiological groups., Conclusion: Hyperprolactinaemia is common among patients evaluated in a primary care setting with symptoms of hyperprolactinaemia, but more than 50% of cases are due to pharmacological treatments or improper sample extraction. It is necessary to establish referral protocols to specialised medicine to optimise healthcare resources and avoid unnecessary studies., (Copyright © 2022 SEEN and SED. Published by Elsevier España, S.L.U. All rights reserved.)