LOINCActiveBoth

LOINC Code 56990-5: T. gondii IgG avidity IA (S) [Ratio]

56990-5 is a LOINC code used to identify T. gondii IgG avidity IA (S) [Ratio] in laboratory and clinical observation data. You may see this code in lab systems, lab reports, EHR exports, interoperability feeds, or other structured clinical data exchanges. LOINC codes identify tests, measurements, observations, survey items, and clinical questions in a standardized way. It is associated with the component Toxoplasma gondii Ab.IgG avidity. It is commonly used with the system or sample type Ser.

Reviewed by HealthAssure Clinical TeamUpdated 21 May 2026

What is this code?

LOINC codes identify tests, measurements, observations, survey items, and clinical questions in a standardized way. It is associated with the component Toxoplasma gondii Ab.IgG avidity. It is commonly used with the system or sample type Ser.

When is it used?

  • Used in lab systems, EHRs, and clinical data exchange.
  • May identify a test, observation, survey item, or clinical document request rather than a diagnosis.
  • Status: ACTIVE
  • Order vs observation: Both
  • Method: IA

What it does not mean

  • The code identifies the observation or test, not the actual result.

Key facts

  • Toxoplasma gondii IgG Ab avidity [Ratio] in Serum by Immunoassay
  • Toxoplasma gondii Ab.IgG avidity
  • ABS; Aby; Antby; Anti; Antibodies; Antibody; Autoantibodies; Autoantibody; EIA; ELFA; ELISA; Enzyme immunoassay; IAA; ID; Immune globulin G; Immunoglobulin G; Infectious Disease; InfectiousDisease; MEIA; Microbiology; Point in time; QNT; Quan; Quant; Quantitative; Random; Ratios; Rto; Serum; SR; SUDS; T gondii; Toxo; Toxoplasmosis

Where you may see this code

You may see this code in lab systems, lab reports, EHR exports, interoperability feeds, or other structured clinical data exchanges.

Common synonyms

T. gondii IgG avidity IA (S) [Ratio]Toxoplasma gondii IgG Ab avidity [Ratio] in Serum by ImmunoassayT gondii IgG Avidity Ser IA-RtoToxoplasma gondii Ab.IgG avidityMICROToxoplasma gondii IgG avidity, BloodRatio

Frequently asked questions

Code details

Code56990-5
SystemLOINC
Display nameT. gondii IgG avidity IA (S) [Ratio]
DescriptionToxoplasma gondii Ab.IgG avidity
Short nameT gondii IgG Avidity Ser IA-Rto
ComponentToxoplasma gondii Ab.IgG avidity
PropertyRatio
TimingPt
System (specimen)Ser
ScaleQn
MethodIA
ClassMICRO
Example units%
StatusACTIVE
Order/ObservationBoth

Flags

BillableNo
Valid clinical useNo

Source

SourceLOINC
Version2.82
Releasemain
First released2.29
Last changed2.56

Consumer names

Toxoplasma gondii IgG avidity, Blood

Part names

Toxoplasma gondii Ab.IgG avidityRatioPtSerQnIAToxoplasma gondii IgG AvidityPoint in time (spot)SerumImmunoassay

About this content

This page is prepared by HealthAssure's clinical team using official coding standards from LOINC. AI tools assist with drafting explanations, which are then reviewed and verified by healthcare professionals for accuracy. This content is for informational purposes and does not replace professional medical advice. Meet our team.