Version 2.80

Term Description

Thyroid secretory capacity (also called thyroid output or GT) is the maximum secretion rate of the thyroid gland under stimulated conditions. The structure parameter inference approach (SPINA) uses Michaelis-Menten functions and pharmakokinetic data to estimate GT under conditions of substrate saturation. One calculation is based on peripheral TSH, free T4, thyroid binding globulin and thyroid binding prealbumin values, and an alternate calculation uses peripheral TSH and total T4. GT calculated using the SPINA approach is also known as SPINA-GT. SPINA-GT may be useful in diagnosing secondary or tertiary thyroid conditions and has also been shown to be able to clearly differentiate between euthyroidism and functional thyroid disorders of primary origin. PMID: 27375554 Peripheral deiodinase activity by SPINA, called SPINA-GD, is a related result [LOINC: 82367-4].

Part Description

LP182359-2   Thyroid secretory capacity
Thyroid's secretory capacity, also referred to as thyroid output or thyroid capacity provides an estimate for the maximum secretion rate of the thyroid gland under stimulated conditions. Thyroid secrectory capacity is elevated in hyperthyroidism and reduced in hypothyroidism. PMID: 27375554

Estimated maximum stimulated amount of thyroxine that the thyroid can produce in one second. SPINA-GT is calculated with GT = BetaT * (DT + [TSH]) * (1 + K41 [TBG] + K42 [TBPA]) * [FT4] / (AlphaT * [TSH]) or GT = BetaT * (DT + [TSH]) * [TT4] / (AlphaT * [TSH]) from serum or plasma concentrations of thyrotropin (TSH) and free (FT4) or total (TT4) thyroxine and some constants (AlphaT = Dilution factor for T4: 0.1 l-1; BetaT = Clearance exponent for T4: 1.1e-6 sec-1; K41 = Dissociation constant T4-TBG: 2e10 l/mol; K42 = Dissociation constant T4-TBPA: 2e8 l/mol, DT = EC50 for TSH: 2.75 mU/l) Source: Regenstrief LOINC

Fully-Specified Name

Component
Thyroid secretory capacity
Property
SRat
Time
Pt
System
Ser/Plas
Scale
Qn
Method
Calculated.SPINA

Additional Names

Long Common Name
Thyroid secretory capacity [Moles/time] in Serum or Plasma by Calculated.SPINA
Short Name
Thyr secr cap SerPl Calc SPINA-sRate
Display Name
Thyroid secretory capacity Calculated by SPINA [Moles/Time]
Consumer Name Alpha Get Info
Thyroid secretory capacity, Blood

Basic Attributes

Class
CHEM
Type
Laboratory
First Released
Version 2.58
Last Updated
Version 2.58 (ADD)
Order vs. Observation
Both

Formula (Readable)

GT = BetaT * (DT + [TSH]) * (1 + K41 [TBG] + K42 [TBPA]) * [FT4] / (AlphaT * [TSH]) or GT = BetaT * (DT + [TSH]) * [TT4] / (AlphaT * [TSH]) Please see [PMID: 27375554] for more information about the constants, AlphaT, BetaT, K41, K42, TBPA, and DT.

Language Variants Get Info

Tag Language Translation
el-GR Greek (Greece) Εκκριτική ικανότητα του θυρεοειδούς:SRat:Pt:Ορός/Πλάσμα:Qn:Υπολογιζόμενο.SPINA
Synonyms: SRat Εκκριτική ικανότητα του θυρεοειδούς
es-ES Spanish (Spain) Capacidad secretora del tiroides:Indice de susbtancia:Punto temporal:Suero o Plasma:Qn:SPINA calculado
Synonyms: Cuantitativo
es-MX Spanish (Mexico) Capacidad secretora tiroidea:Tasa de sustancia:Punto temporal:Suero o Plasma:Cuantitativo:Calculado.SPINA
fr-FR French (France) Capacité secrétoire de la thyroïde:Moles/Temps:Ponctuel:Sérum/Plasma:Numérique:SPINA calculé
it-IT Italian (Italy) Tiroide, capacità secretiva:SRat:Pt:Siero/Plasma:Qn:Calcolato.SPINA
Synonyms: Calcolato mediante SPINA Capacità secretiva della tiroide Chimica Plasma Punto nel tempo (episodio) Siero Siero o Plasma Tasso di sostanza
zh-CN Chinese (China) 甲状腺分泌能力:物质的量速率:时间点:血清/血浆:定量型:计算法.SPINA
Synonyms: Thyroid secretory capacity;TSC;甲状腺输出（分泌、排出、产出）速度（速率）;thyroid output;GT 克分子速率;克分子速率(单位时间);摩尔速率;摩尔速率(单位时间);物质的量速率(单位时间) 化学;化学检验项目;化学检验项目类;化学类;化学试验;非刺激耐受型化学检验项目;非刺激耐受型化学检验项目类;非刺激耐受型化学试验;非刺激耐受型化学试验类 可用数量表示的;定量性;数值型;数量型;连续数值型标尺 时刻;随机;随意;瞬间 甲状腺特异性 甲状腺的 结构参数推理法;structure parameter inference approach;SPINA 血清或血浆 计算;计算型方法

Example Units

Unit Source
pmol/s Example UCUM Units

LOINC Terminology Service (API) using HL7® FHIR® Get Info

CodeSystem lookup
https://fhir.loinc.org/CodeSystem/$lookup?system=http://loinc.org&code=82368-2