LP28551-7
Thyroxine free index
Active
Description
Free thyroxine index (FT4I, FTI) is calculated from total hormone (TT4) and any one of the thyroid hormone uptakes - see LOINCs 3050-2 (Triiodothyronine resin uptake, T3RU), 74794-9 (Thyroid hormone binding ratio, THBR), 74793-1 (Classic T-uptake), and 74795-6 (Total thyroxine binding capacity). It adjusts total hormone levels for the number of binding sites to provide a better picture of thyroid status than total hormone levels. Results may vary depending on which T-uptake is used. If that level of distinction is important, users should look to the associated T-uptake code. However, little reason exists to depend on a Free T4 index today now that Free T4 measures are widely available, accurate and more economical than measuring a T-uptake and a TT4. Source: Regenstrief LOINC
Basic Part Properties
- Part Name
- Thyroxine free index
- Part Display Name
- Thyroxine free index
- Part Type
- Component (Describes the core component or analyte measured)
- Created On
- 2001-09-10
- Construct for LOINC Short Name
- FT4I
LOINC Terminology Service (API) using HL7® FHIR® Get Info
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- CodeSystem lookup
- https:
//fhir.loinc.org/CodeSystem/$lookup?system=http: //loinc.org&code=LP28551-7
Language Variants Get Info
| Tag | Language | Translation |
|---|---|---|
| zh-CN | Chinese (China) | 游离型甲状腺素指数 Synonyms: FT4I; |
| es-ES | Spanish (Spain) | Índice de tiroxina libre |
| it-IT | Italian (Italy) | Tiroxina libera, indice Synonyms: Indice di tiroxina libera |
| tr-TR | Turkish (Turkey) | Tiroksin serb indeksi |
| ru-RU | Russian (Russian Federation) | Тироксин свободный индекс |
| fr-BE | French (Belgium) | Indice de thyroxine libre Synonyms: IT4L |
| fr-CA | French (Canada) | Indice de thyroxine libre |
| nl-NL | Dutch (Netherlands) | thyroxine vrij index |
| pl-PL | Polish (Poland) | Wolna tyroksyna, indeks |
| el-GR | Greek (Greece) | Δείκτης ελεύθερης θυροξίνης Synonyms: Δείκτης ελεύθερης θυροξίνης |
LOINC Copyright
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