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 27813-5: Prothrombin Ag actual/normal IA (PPP) [Relative mass conc]

Name: LOINC Code 27813-5: Prothrombin Ag actual/normal IA (PPP) [Relative mass conc]
Creator: HealthAssure Clinical Team
Published: 2026-05-21T08:59:14.572Z

27813-5 is a LOINC code used to identify Prothrombin Ag actual/normal IA (PPP) [Relative mass conc] 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 Prothrombin Ag actual/Normal. It is commonly used with the system or sample type PPP.

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 Prothrombin Ag actual/Normal. It is commonly used with the system or sample type PPP.

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

Prothrombin Ag actual/normal in Platelet poor plasma by Immunoassay
Prothrombin Ag actual/Normal
Act/Nor; Ag Act/Nor; Antigen; Antigens; COAGULATION; Coagulation factor II; Control; EIA; ELFA; ELISA; Enzyme immunoassay; Factor 2; Factor II; Hematology; Heme; IAA; MEIA; Plas; Platelet poor plasma; Point in time; Prothombin; Prothrm; Prothromb; QNT; Quan; Quant; Quantitative; Random; Relative mass concentration; RLMCNC; 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

Prothrombin Ag actual/normal IA (PPP) [Relative mass conc]Prothrombin Ag actual/normal in Platelet poor plasma by ImmunoassayProthrom Ag Act/Nor PPP IAProthrombin Ag actual/NormalCOAGProthrombin antigen activity, BloodRelMCnc

Frequently asked questions

Code details

Code27813-5

SystemLOINC

Display nameProthrombin Ag actual/normal IA (PPP) [Relative mass conc]

DescriptionProthrombin Ag actual/Normal

Short nameProthrom Ag Act/Nor PPP IA

ComponentProthrombin Ag actual/Normal

PropertyRelMCnc

TimingPt

System (specimen)PPP

ScaleQn

MethodIA

ClassCOAG

Example units%

StatusACTIVE

Order/ObservationObservation

Flags

BillableNo

Valid clinical useNo

Source

SourceLOINC

Version2.82

Releasemain

First released2.00

Last changed2.73

Consumer names

Prothrombin antigen activity, Blood

Part names

Prothrombin Ag actual/NormalRelMCncPtPPPQnIARelative Mass ConcentrationPoint in time (spot)Platelet poor 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.