What does this LOINC code represent?

This LOINC code identifies a lab observation, measurement, question, or clinical concept in a standardized format.

Is this enough to understand my test result?

No. The code identifies the test or observation, but the interpretation depends on the actual result, reference range, and clinical context.

LOINCActiveObservation

LOINC Code 77640-1: HLA class I and II IgG IA Nar [Interp]

Name: LOINC Code 77640-1: HLA class I and II IgG IA Nar [Interp]
Creator: HealthAssure Clinical Team
Published: 2026-05-21T08:59:58.754Z

77640-1 is a LOINC code used to identify HLA class I and II IgG IA Nar [Interp] 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 HLA class I & II Ab.IgG. It is commonly used with the system or sample type Ser/Plas.

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 HLA class I & II Ab.IgG. It is commonly used with the system or sample type Ser/Plas.

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: Observation
Method: IA

What it does not mean

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

Key facts

HLA class I and II IgG Ab in Serum or Plasma by Immunoassay [interpretation] Narrative
HLA class I & II Ab.IgG
Interpretation term for an HLA assay that identifies specific HLA class I (A, B and C) and class II (DP, DQ and DR) antibodies.
2; ABS; Aby; Antby; Anti; Antibodies; Antibody; Autoantibodies; Autoantibody; EIA; ELFA; ELISA; Enzyme immunoassay; HLA ANTIGEN; HLA class I + II; Human Leukocyte Antigen; IAA; Immune globulin G; Immunoglobulin G; Impression; Impression/interpretation of study; Impressions; Interp; Interpretation; MEIA; Narrative; Pl; Plasma; Plsm; Point in time; Random; Report; SerP; SerPl; SerPlas; Serum; Serum or plasma; SR; SUDS

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

HLA class I and II IgG IA Nar [Interp]HLA class I and II IgG Ab in Serum or Plasma by Immunoassay [interpretation] NarrativeHLA class I + II IgG SerPl IA-ImpHLA class I & II Ab.IgGHLAInterpretation of HLA Class I and II IgG antibody test result, BloodImp

Frequently asked questions

Code details

Code77640-1

SystemLOINC

Display nameHLA class I and II IgG IA Nar [Interp]

DescriptionHLA class I & II Ab.IgG

Short nameHLA class I + II IgG SerPl IA-Imp

ComponentHLA class I & II Ab.IgG

PropertyImp

TimingPt

System (specimen)Ser/Plas

ScaleNar

MethodIA

ClassHLA

StatusACTIVE

Order/ObservationObservation

Flags

BillableNo

Valid clinical useNo

Source

SourceLOINC

Version2.82

Releasemain

First released2.52

Last changed2.56

Consumer names

Interpretation of HLA Class I and II IgG antibody test result, Blood

Part names

HLA class I & II Ab.IgGImpPtSer/PlasNarIAHLA class I and II IgGImpression/interpretation of studyPoint in time (spot)Serum or PlasmaImmunoassay

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.