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 20634-2: Alpha aminobutyrate [Moles/Vol]

Name: LOINC Code 20634-2: Alpha aminobutyrate [Moles/Vol]
Creator: HealthAssure Clinical Team
Published: 2026-05-25T17:13:11.347Z

20634-2 is a LOINC code used to identify Alpha aminobutyrate [Moles/Vol] 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 Alpha aminobutyrate. It is commonly used with the system or sample type Ser/Plas.

Reviewed by HealthAssure Clinical TeamUpdated 25 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 Alpha aminobutyrate. 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

What it does not mean

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

Key facts

Alpha aminobutyrate [Moles/volume] in Serum or Plasma
Alpha aminobutyrate
Genetic metabolic specialist (from Canada) point out that plasma may be the traditional sample of choice, but they see no clinically significant difference between plasma and serum amino acids.
2-aminobutanoic acid; 2-aminobutyrate; 2-aminobutyric acid; A-Aminobutyr; AANB; A-ANB; Alfa; Alpha aminobutyric acid; Alpha amino-n-butyrate; Alpha amino-n-butyric acid; Aminobutric; Aminobutyric; Amino-n-butyrate; Chemistry; Level; Pl; Plasma; Plsm; Point in time; QNT; Quan; Quant; Quantitative; Random; SerP; SerPl; SerPlas; Serum; Serum or plasma; SR; Substance concentration

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.

Related SNOMED CT concepts

705114005SNOMED CT mapping for Alpha aminobutyrate [Moles/Vol] (20634-2)

Related observations and tests

SNOMED_CT 705114005high

LOINC Code System

Source: LOINC-SNOMED cooperation package

Common synonyms

Alpha aminobutyrate [Moles/Vol]Alpha aminobutyrate [Moles/volume] in Serum or PlasmaA-Aminobutyr SerPl-sCncAlpha aminobutyrateCHEMAlpha aminobutyrate, BloodSCnc

Frequently asked questions

Code details

Code20634-2

SystemLOINC

Display nameAlpha aminobutyrate [Moles/Vol]

DescriptionAlpha aminobutyrate

Short nameA-Aminobutyr SerPl-sCnc

ComponentAlpha aminobutyrate

PropertySCnc

TimingPt

System (specimen)Ser/Plas

ScaleQn

ClassCHEM

Example unitsmcmol/dL; mcmol/L; umol/L

StatusACTIVE

Order/ObservationObservation

Flags

BillableNo

Valid clinical useNo

Source

SourceLOINC

Version2.82

Releasemain

First released1.0m

Last changed2.73

Consumer names

Alpha aminobutyrate, Blood

Part names

Alpha aminobutyrateSCncPtSer/PlasQnSubstance ConcentrationPoint in time (spot)Serum or Plasma

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.