LOINCActiveBoth

LOINC Code 43581-8: Complement C4 (Periton fld) [Mass/Vol]

43581-8 is a LOINC code used to identify Complement C4 (Periton fld) [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 C4. It is commonly used with the system or sample type Periton fld.

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 C4. It is commonly used with the system or sample type Periton fld.

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 C4 [Mass/volume] in Peritoneal fluid
  • Complement C4
  • Ascites; Ascitic fluid; Ascitis; Beta 1 E-globulin; Comp; Complmt; HEMATOLOGY/CELL COUNTS; Level; Mass concentration; Peritoneal fluid; Point in time; Prt; QNT; Quan; Quant; Quantitative; Random

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 C4 (Periton fld) [Mass/Vol]Complement C4 [Mass/volume] in Peritoneal fluidC4 Prt-mCncComplement C4HEM/BCComplement C4, Peritoneal fluidMCnc

Frequently asked questions

Code details

Code43581-8
SystemLOINC
Display nameComplement C4 (Periton fld) [Mass/Vol]
DescriptionComplement C4
Short nameC4 Prt-mCnc
ComponentComplement C4
PropertyMCnc
TimingPt
System (specimen)Periton fld
ScaleQn
ClassHEM/BC
Example unitsmg/dL
StatusACTIVE
Order/ObservationBoth

Flags

BillableNo
Valid clinical useNo

Source

SourceLOINC
Version2.82
Releasemain
First released2.17
Last changed2.70

Consumer names

Complement C4, Peritoneal fluid

Part names

Complement C4MCncPtPeriton fldQnMass ConcentrationPoint in time (spot)Peritoneal fluid

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.

LOINC Code 43581-8 | HealthAssure