Thyroid function testing
Summary
Details
- Thyroid hormone production
- Thyroid hormone-binding proteins
- Indications for TFTs: general considerations
- Known thyroid dysfunction and preconception
- Screening for thyroid dysfunction during pregnancy
- Screening for congenital hypothyroidism
- TFTs
- Low TSH - associated with a high FT4 and/or FT3
- Low TSH - associated with a low FT4 and/or FT3
- Low TSH - associated with a normal FT4 and/or FT3
- High TSH - associated with a high FT4 and/or FT3
- High TSH - associated with a low FT4 and/or FT3
- High TSH - associated with a normal FT4 and/or FT3
- Normal TSH - associated with a low FT4 and/or FT3
- Drug effects
Contributors
Authors
Joel Ehrenkranz, MD
Associate Professor
Division of Chemistry and Chemical Engineering
California Institute of Technology
Pasadena
CA
Disclosures
JE declares that he has served on a writing group for the American Thyroid Association which drafted an article on thyroid function testing and was submitted for publication to the journal Thyroid.
Acknowledgements
Dr Joel Ehrenkranz would like to gratefully acknowledge Dr Mae Sheikh-Ali, Dr Harshit Shah, Dr Melanie Thomas, Dr Anna Szafran-Swietlik, Dr Sandra Mesliniene, Dr Emad Naem, and Dr Abdul-Razzak Alamir, previous contributors to this topic. HS, MT, AS-S, SM, EN, and A-RA declare that they have no competing interests. MS-A declares she is a speaker for IBSA and AbbVie. Both have brand names for levothyroxine (LT4) medication.
Peer reviewers
Ronald Merrell, MD
Professor of Surgery
Virginia Commonwealth University
Richmond
VA
Disclosures
RM declares that he has no competing interests.
Georg Hennemann, MD
Professor of Medicine and Endocrinology
Medical Center Spijkenisse
The Hague
The Netherlands
Disclosures
Not disclosed.
Simon Pearce, MD
Professor of Endocrinology
Newcastle University
Endocrine Unit
Royal Victoria Infirmary
Newcastle upon Tyne
UK
Disclosures
SP declares that he has no competing interests.
V.S. Schneider, MD
Clinical Associate Professor of Medicine
Uniformed Services University of the Health Sciences
Bethesda
MD
MA and Senior Medical Advisor
NASA Headquarters
Washington
DC
Disclosures
VSS declares that he has no competing interests.
Patient information
Underactive thyroid
More Patient information
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