74794-9
Thyroid hormone binding ratio (THBR) in Serum or Plasma
Active
Part Description
LP183620-6 Thyroid hormone binding ratio
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
Fully-Specified Name
- Component
- Thyroid hormone binding ratio
- Property
- RelRto
- Time
- Pt
- System
- Ser/Plas
- Scale
- Qn
- Method
Additional Names
- Long Common Name
- Thyroid hormone binding ratio (THBR) in Serum or Plasma
- Short Name
- THBR SerPl
- Display Name
- Thyroid hormone binding ratio (THBR) [Relative ratio]
- Consumer Name Alpha Get Info
- Thyroid Hormone Binding Ratio (THBR), Blood
Basic Attributes
- Class
- CHEM
- Type
- Laboratory
- First Released
- Version 2.48
- Last Updated
- Version 2.48 (MIN)
- Order vs. Observation
- Both
Language Variants Get Info
Tag | Language | Translation |
---|---|---|
el-GR | Greek (Greece) | Αναλογία δέσμευσης θυρεοειδικής ορμόνης: Synonyms: RelRto Αναλογία δέσμευσης θυρεοειδικής ορμόνης |
es-ES | Spanish (Spain) | Porcentaje de fijación de hormona tiroidea: Synonyms: Cuantitativo |
es-MX | Spanish (Mexico) | Relación de unión a la hormona tiroidea: |
fr-FR | French (France) | Thyroid hormone binding ratio: |
it-IT | Italian (Italy) | Tiroide, rapporto di legame degli ormoni: Synonyms: Chimica Plasma Punto nel tempo (episodio) Rapporto di legame degli ormoni tiroidei Rapporto Relativo Siero Siero o Plasma |
nl-NL | Dutch (Netherlands) | thyroïdhormoon binding ratio: Synonyms: thyroid hormoon binding ratio |
pt-BR | Portuguese (Brazil) | Hormônio da tiróide ligação relação: |
ru-RU | Russian (Russian Federation) | Тиреоидный гормон связывание отношение: Synonyms: Количественный Относительный показатель; |
tr-TR | Turkish (Turkey) | Tiroid hormonu bağlama oranı: |
zh-CN | Chinese (China) | 甲状腺激素结合率: Synonyms: 化学; |
Example Units
Unit | Source |
---|---|
{ratio} | Example UCUM Units |
LOINC Terminology Service (API) using HL7® FHIR® Get Info
Requests to this service require a free LOINC username and password. Below is a sample of the possible capabilities. See the LOINC Terminology Service documentation for more information.
- CodeSystem lookup
- https:
//fhir.loinc.org/CodeSystem/$lookup?system=http: //loinc.org&code=74794-9
LOINC Copyright
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