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 4477-6: Complement C1 esterase inhibitor [Mass/Vol]

Name: LOINC Code 4477-6: Complement C1 esterase inhibitor [Mass/Vol]
Creator: HealthAssure Clinical Team
Published: 2026-05-25T17:13:11.347Z

4477-6 is a LOINC code used to identify Complement C1 esterase inhibitor [Mass/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 Complement C1 esterase inhibitor. 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 Complement C1 esterase inhibitor. 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

What it does not mean

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

Key facts

Complement C1 esterase inhibitor [Mass/volume] in Serum or Plasma
Complement C1 esterase inhibitor
C1 inactivator; C1 inhibiting factor; C1INA; C1INH; C1-INH; Comp; Complmt; HEMATOLOGY/CELL COUNTS; Inhib; Inhibit; Level; Mass concentration; Pl; Plasma; Plsm; Point in time; QNT; Quan; Quant; Quantitative; Random; SerP; SerPl; SerPlas; Serum; Serum or plasma; SR; UniversalLabOrders

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 Complement C1 esterase inhibitor [Mass/Vol] (4477-6)

Related observations and tests

SNOMED_CT 705114005high

LOINC Code System

Source: LOINC-SNOMED cooperation package

Common synonyms

Complement C1 esterase inhibitor [Mass/Vol]Complement C1 esterase inhibitor [Mass/volume] in Serum or PlasmaC1INH SerPl-mCncComplement C1 esterase inhibitorHEM/BCComplement C1 Esterase Inhibitor, BloodMCnc

Frequently asked questions

Code details

Code4477-6

SystemLOINC

Display nameComplement C1 esterase inhibitor [Mass/Vol]

DescriptionComplement C1 esterase inhibitor

Short nameC1INH SerPl-mCnc

ComponentComplement C1 esterase inhibitor

PropertyMCnc

TimingPt

System (specimen)Ser/Plas

ScaleQn

ClassHEM/BC

Example unitsg/L;mg/dL

StatusACTIVE

Order/ObservationBoth

Flags

BillableNo

Valid clinical useNo

Source

SourceLOINC

Version2.82

Releasemain

First released1.0

Last changed2.73

Consumer names

Complement C1 Esterase Inhibitor, Blood

Part names

Complement C1 esterase inhibitorMCncPtSer/PlasQnMass 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.