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.

LOINCActiveBoth

LOINC Code 58462-3: Complement functional activity IA Qn

Name: LOINC Code 58462-3: Complement functional activity IA Qn
Creator: HealthAssure Clinical Team
Published: 2026-05-21T08:59:39.275Z

58462-3 is a LOINC code used to identify Complement functional activity IA Qn 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 Complement functional activity. 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 Complement functional activity. 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: Both
Method: IA

What it does not mean

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

Key facts

Complement functional activity [Units/volume] in Serum or Plasma by Immunoassay
Complement functional activity
Activ; Actvty; Arbitrary concentration; Comp; Comp functional activity; Complement screening; Complmt; EIA; ELFA; ELISA; Enzyme immunoassay; HEMATOLOGY/CELL COUNTS; IAA; MEIA; Movements; Pl; Plasma; Plsm; Point in time; QNT; Quan; Quant; Quantitative; Random; 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

Complement functional activity IA QnComplement functional activity [Units/volume] in Serum or Plasma by ImmunoassayComp functional activity SerPl IA-aCncComplement functional activityHEM/BCComplement functional activity, BloodACnc

Frequently asked questions

Code details

Code58462-3

SystemLOINC

Display nameComplement functional activity IA Qn

DescriptionComplement functional activity

Short nameComp functional activity SerPl IA-aCnc

ComponentComplement functional activity

PropertyACnc

TimingPt

System (specimen)Ser/Plas

ScaleQn

MethodIA

ClassHEM/BC

StatusACTIVE

Order/ObservationBoth

Flags

BillableNo

Valid clinical useNo

Source

SourceLOINC

Version2.82

Releasemain

First released2.32

Last changed2.73

Consumer names

Complement functional activity, Blood

Part names

Complement functional activityACncPtSer/PlasQnIAArbitrary ConcentrationPoint 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.