LOINCActiveBoth

LOINC Code 31931-9: P. vivax Ag Qn (Bld)

31931-9 is a LOINC code used to identify P. vivax Ag Qn (Bld) 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 Plasmodium vivax Ag. It is commonly used with the system or sample type Bld.

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 Plasmodium vivax Ag. It is commonly used with the system or sample type Bld.

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

  • Plasmodium vivax Ag [Units/volume] in Blood
  • Plasmodium vivax Ag
  • Antigen; Antigens; Arbitrary concentration; Blood; ID; Infectious Disease; InfectiousDisease; Malaria; Malarial; Microbiology; P vivax; Point in time; QNT; Quan; Quant; Quantitative; Random; WB; Whole blood

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

P. vivax Ag Qn (Bld)Plasmodium vivax Ag [Units/volume] in BloodP vivax Ag Bld-aCncPlasmodium vivax AgMICROPlasmodium vivax antigen, BloodACnc

Frequently asked questions

Code details

Code31931-9
SystemLOINC
Display nameP. vivax Ag Qn (Bld)
DescriptionPlasmodium vivax Ag
Short nameP vivax Ag Bld-aCnc
ComponentPlasmodium vivax Ag
PropertyACnc
TimingPt
System (specimen)Bld
ScaleQn
ClassMICRO
StatusACTIVE
Order/ObservationBoth

Flags

BillableNo
Valid clinical useNo

Source

SourceLOINC
Version2.82
Releasemain
First released2.07
Last changed2.69

Consumer names

Plasmodium vivax antigen, Blood

Part names

Plasmodium vivax AgACncPtBldQnArbitrary ConcentrationPoint in time (spot)Blood

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 31931-9 | HealthAssure