LP183619-8
Thyroid hormone uptake
Active
Description
Thyroid hormone uptake ("T-uptake") assays provide information on the number of thyroid hormone binding sites, consisting primarily of thyroid binding globulin, thyroxine binding prealbumin and albumin. Since both T4 and T3 bind to these proteins, different assay formats have used either labeled T3 or T4 (the classic T3 resin uptake uses T3). Various T-uptake assays can differ in the units reported (and even the phenomena being measured), requiring mindfulness when selecting LOINC codes. Being used in the calculation of free T3 and free T4 index (FTI), the T-uptake variants also proliferate into variants of FTI. The classic T-uptake reported as % represents the proportion of labeled thyroid hormone (either T3 or T4) added to a sample that remains unbound (modern assays: use LOINC 74793-1; T3 resin uptake method: 3050-2). T-uptake reported as ratio of patient /control is known as thyroid hormone binding ratio, or THBR or T-uptake ratio (use LOINC 74794-9). T-uptake % and THBR generally are inversely proportional to the number of unoccupied thyroid hormone binding sites present. Alternative assay methods that report T-uptake as "T-uptake units" are described as being directly proportional to the total binding capacity (use LOINC 74795-6).
However, the major rationale for measuring the T-Uptake was to obtain a factor for estimating the free T4 (the biologically relevant fraction). Now that Free T4 measures are widely available, accurate and more economical than measuring a T-uptake AND a TT4 , use of the uptake has been discouraged by most experts. Canada has taken the position of not paying for T-uptake measures.
Source: Regenstrief LOINC
Basic Part Properties
- Part Name
- Thyroid hormone uptake
- Part Display Name
- Thyroid hormone uptake (T-uptake)
- Part Type
- Component (Describes the core component or analyte measured)
- Created On
- 2014-04-17
- Construct for LOINC Short Name
- T-uptake
LOINC Terminology Service (API) using HL7® FHIR® Get Info
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- CodeSystem lookup
- https:
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Language Variants Get Info
| Tag | Language | Translation |
|---|---|---|
| zh-CN | Chinese (China) | 甲状腺激素摄取 Synonyms: 甲状腺荷尔蒙摄取 |
| ru-RU | Russian (Russian Federation) | Тиреоидный гормон захват |
| es-ES | Spanish (Spain) | Captación de hormona tiroidea |
| it-IT | Italian (Italy) | Tiroide, asoorbimento ormone Synonyms: Assorbimento dell''ormone tiroideo |
| tr-TR | Turkish (Turkey) | Tiroid hormon uptake Synonyms: Tiroid hormon kullanımı |
| nl-NL | Dutch (Netherlands) | thyroïdhormoon opname Synonyms: thyroid hormoon opname |
| el-GR | Greek (Greece) | Πρόσληψη θυρεοειδικής ορμόνης Synonyms: Πρόσληψη θυρεοειδικής ορμόνης |
LOINC Copyright
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