Assessment of Histamine and Diamine Oxidase Levels in Patients with Hashimoto’s Thyroiditis: A Cross-Sectional Study

Objective: Chronic inflammation in Hashimoto’s thyroiditis (HT) might influence histamine metabolism and DAO activity and limited data exists about this condition.

Methods: Data were obtained from 25 HT patients and 38 healthy controls who visited the outpatient clinic between December 2023 and March 2024. Demographic, clinical, and laboratory information were extracted from patient records. Thyroid-stimulating hormone, free T4, free triiodothyronine, anti-TPO, and anti-thyroglobulin antibodies levels were retrieved from the files, while histamine, serotonin and tryptophan levels were detected using the LC-MS/MS method.

Results: The mean ages of HT and control groups were 40.52 ± 11.60 and 36.61 ± 11.04 years, respectively. Notable statistical differences were identified among the groups concerning anti-thyroglobulin antibodies, anti-thyroid peroxidase antibodies, high-density lipoprotein, and triglyceride concentrations. The levels of histamine, serotonin, and tryptophan were not statistically different between the 2 groups, however, a statistically significant elevation in DAO levels was assessed in the HT group relative to the control group.

Conclusion: The data figured out borderline significant changes in DAO levels in the serum of HT compared to control group, and serum levels of DAO were higher in HT. This is the initial investigation to assess DAO levels in HT and compared histamine and DAO levels in HT.

Cite this article as: Ozisik H, Yelpaze M, Şeren N, et al. Assessment of histamine and diamine oxidase levels in patients with Hashimoto’s thyroiditis: A cross-sectional study. Endocrinol Res Pract. 2025;29(3):211-215.