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 23781-8: Swine influenza virus Ag IF Ql (Tiss)

Name: LOINC Code 23781-8: Swine influenza virus Ag IF Ql (Tiss)
Creator: HealthAssure Clinical Team
Published: 2026-05-21T08:59:12.417Z

23781-8 is a LOINC code used to identify Swine influenza virus Ag IF Ql (Tiss) 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 Swine influenza virus Ag. It is commonly used with the system or sample type Tiss.

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 Swine influenza virus Ag. It is commonly used with the system or sample type Tiss.

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
Method: IF

What it does not mean

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

Key facts

Swine influenza virus Ag [Presence] in Tissue by Immunofluorescence
Swine influenza virus Ag
ACIF; Anticomplement Immunofluorescence; Antigen; Antigens; DFA; FA; Fluorescent antibody; Fluoresent; FLUV; ID; IFA; Immune fluorescence; Immunoflour; Immunofluor; Immunofluorescence; Infectious Disease; InfectiousDisease; Influ; Microbiology; Ordinal; Pig; Point in time; Pork; PR; QL; Qual; Qualitative; Random; Screen; SIV; Swine influenza; Time Resolved Fluorescence; Tissue; Tissue, unspecified; TRF

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

Swine influenza virus Ag IF Ql (Tiss)Swine influenza virus Ag [Presence] in Tissue by ImmunofluorescenceSIV Ag Tiss Ql IFSwine influenza virus AgMICROSwine Influenza virus antigen, TissuePrThr

Frequently asked questions

Code details

Code23781-8

SystemLOINC

Display nameSwine influenza virus Ag IF Ql (Tiss)

DescriptionSwine influenza virus Ag

Short nameSIV Ag Tiss Ql IF

ComponentSwine influenza virus Ag

PropertyPrThr

TimingPt

System (specimen)Tiss

ScaleOrd

MethodIF

ClassMICRO

StatusACTIVE

Order/ObservationBoth

Flags

BillableNo

Valid clinical useNo

Source

SourceLOINC

Version2.82

Releasemain

First released1.0n

Last changed2.56

Consumer names

Swine Influenza virus antigen, Tissue

Part names

Swine influenza virus AgPrThrPtTissOrdIFPresence or ThresholdPoint in time (spot)Tissue and SmearsImmunofluorescence (IF)

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.