Factitious thyrotoxicosis: how to find it
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Pakaworn Vorasart
Abstract
Background
Although the most common cause of thyrotoxicosis is Graves’ disease, the determination of the cause of thyrotoxicosis is important for establishing appropriate management. Diagnosis of surreptitious ingestion of thyroid hormones or factitious thyrotoxicosis often presents a difficult challenge especially in a patient with previously diagnosed Graves’ disease. The objective of this report was to demonstrate various approaches to support the diagnosis of factitious thyrotoxicosis.
Case presentation
We describe a patient with underlying Graves’ disease who underwent definitive therapy and needed long-term levothyroxine (LT4) replacement therapy. Later she developed thyrotoxicosis. Although factitious thyrotoxicosis was suspected because of very low thyroid uptake and low thyroglobulin (Tg) levels with the absence of thyroglobulin antibodies (TgAbs), she still refused any medication or substance use. After the administration of bile acid sequestrant, the thyroid hormone levels rapidly returned to normal within 1 month.
Conclusions
The diagnosis of factitious thyrotoxicosis is based upon the absence of goiter, suppressed serum Tg level, decreased radioactive iodine (RAI) uptake, and excellent response after cholestyramine treatment.
Acknowledgments
The abstract was presented at the 87th Annual Meeting of the American Thyroid Association (ATA) in Victoria, BC, Canada, October 18–22, 2017.
Author contributions: All the authors have accepted responsibility for the entire content of this submitted manuscript and approved the submission.
Research funding: None declared.
Employment or leadership: None declared.
Honorarium: None declared.
Competing interests: None declared.
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©2020 Walter de Gruyter GmbH, Berlin/Boston
Artikel in diesem Heft
- Frontmatter
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- COVID Blindness
- Opinion Paper
- Health risks and potential remedies during prolonged lockdowns for coronavirus disease 2019 (COVID-19)
- Original Articles
- Clinical features, laboratory characteristics, and outcomes of patients hospitalized with coronavirus disease 2019 (COVID-19): Early report from the United States
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- Diagnostic error in an ophthalmic emergency department
- Evaluation of the usefulness of the simultaneous assay of fecal hemoglobin (Hb) and transferrin (Tf) in colorectal cancer screening – for the establishment of the Hb and Tf two-step cutoff assay (HTTC assay)
- Case Report
- Factitious thyrotoxicosis: how to find it
- Letters to the Editors
- Letter to the Editor re Olson et al. “Competencies for improving diagnosis: an interprofessional framework for education and training in healthcare”
- Molecular diagnostics at the times of SARS-CoV-2 outbreak
Artikel in diesem Heft
- Frontmatter
- Editorials
- The novel coronavirus (2019-nCoV) outbreak: think the unthinkable and be prepared to face the challenge
- COVID Blindness
- Opinion Paper
- Health risks and potential remedies during prolonged lockdowns for coronavirus disease 2019 (COVID-19)
- Original Articles
- Clinical features, laboratory characteristics, and outcomes of patients hospitalized with coronavirus disease 2019 (COVID-19): Early report from the United States
- Patient perceptions of misdiagnosis of endometriosis: results from an online national survey
- A survey of outpatient Internal Medicine clinician perceptions of diagnostic error
- Thresholds, rules and defensive strategies: how physicians learn from their prior diagnosis-related experiences
- Updates to referring clinicians regarding critically ill children admitted to the pediatric intensive care unit: a state-wide survey
- Diagnostic error in an ophthalmic emergency department
- Evaluation of the usefulness of the simultaneous assay of fecal hemoglobin (Hb) and transferrin (Tf) in colorectal cancer screening – for the establishment of the Hb and Tf two-step cutoff assay (HTTC assay)
- Case Report
- Factitious thyrotoxicosis: how to find it
- Letters to the Editors
- Letter to the Editor re Olson et al. “Competencies for improving diagnosis: an interprofessional framework for education and training in healthcare”
- Molecular diagnostics at the times of SARS-CoV-2 outbreak
