82367-4

LOINC code 82367-4 identifies "Peripheral deiodinase activity [Moles/time] in Serum or Plasma by Calculated.SPINA". The sum activity of peripheral deiodinases (GD, also referred to as deiodination capacity or total deiodinase activity) is the maximum amount of triiodothyronine (T3) produced per time-unit by deiodinases outside the central nervous system. The structure parameter inference approach (SPINA) uses Michaelis-Menten functions and pharmakokinetic data to estimate GD under conditions of substrate saturation. One calculation is based on peripheral free T3 and free T4 values, and an alternate calculation uses peripheral total T3 and free T4. GD calculated using the SPINA approach is also known as SPINA-GD. SPINA-GD may be useful in diagnosing thyroid conditions that are difficult to diagnose based on traditional thyroid function studies, such as subclinical forms of thyroid failure, hypothalamic or pituitary dysfunction, and non-thyroidal illness syndrome. [PMID: 27375554] Thyroid secretory function by SPINA, called SPINA-GT, is a related result [LOINC: 82368-2].

This code measures Peripheral deiodinase activity in Ser/Plas. It belongs to the CHEM class in the LOINC classification.

LOINC (Logical Observation Identifiers Names and Codes) is a universal standard for identifying laboratory and clinical observations. It is maintained by the Regenstrief Institute and used worldwide for health data exchange.