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 40594-4: Platelet aggregation Qn (PRP)

Name: LOINC Code 40594-4: Platelet aggregation Qn (PRP)
Creator: HealthAssure Clinical Team
Published: 2026-05-21T08:59:27.146Z

40594-4 is a LOINC code used to identify Platelet aggregation Qn (PRP) 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 Platelet aggregation. It is commonly used with the system or sample type PRP.

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 Platelet aggregation. It is commonly used with the system or sample type PRP.

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: Aggregometry.epinephrine induced.100 umol/L

What it does not mean

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

Key facts

Platelet aggregation [Units/volume] in Platelet rich plasma by EPINEPHrine induced 100 umol/L
Platelet aggregation
Agg; Aggr; Arbitrary concentration; COAGULATION; Epineph 100 umol/L; Hematology; Heme; Left; Levo; PA; Pl; Platelet rich plasma; Platelets; Platelt; Plt; Point in time; QNT; Quan; Quant; Quantitative; Random; Thrombocyte; Thrombocytes

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

Platelet aggregation Qn (PRP)Platelet aggregation [Units/volume] in Platelet rich plasma by EPINEPHrine induced 100 umol/LPA PRP Epineph 100 umol/L-aCncPlatelet aggregationCOAGPlatelet Aggregation, BloodACnc

Frequently asked questions

Code details

Code40594-4

SystemLOINC

Display namePlatelet aggregation Qn (PRP)

DescriptionPlatelet aggregation

Short namePA PRP Epineph 100 umol/L-aCnc

ComponentPlatelet aggregation

PropertyACnc

TimingPt

System (specimen)PRP

ScaleQn

MethodAggregometry.epinephrine induced.100 umol/L

ClassCOAG

StatusACTIVE

Order/ObservationObservation

Flags

BillableNo

Valid clinical useNo

Source

SourceLOINC

Version2.82

Releasemain

First released2.15

Last changed2.82

Consumer names

Platelet Aggregation, Blood

Part names

Platelet aggregationACncPtPRPQnAggregometry.epinephrine induced.100 umol/LArbitrary ConcentrationPoint in time (spot)Platelet rich plasmaEPINEPHrine induced 100 umol/L

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.