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 5116-9: C. diphtheriae Ab IA Qn (S)

Name: LOINC Code 5116-9: C. diphtheriae Ab IA Qn (S)
Creator: HealthAssure Clinical Team
Published: 2026-05-21T08:59:35.011Z

5116-9 is a LOINC code used to identify C. diphtheriae Ab IA Qn (S) 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 Corynebacterium diphtheriae Ab. It is commonly used with the system or sample type Ser.

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 Corynebacterium diphtheriae Ab. It is commonly used with the system or sample type Ser.

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: IA

What it does not mean

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

Key facts

Corynebacterium diphtheriae Ab [Units/volume] in Serum by Immunoassay
Corynebacterium diphtheriae Ab
ABS; Aby; Antby; Anti; Antibodies; Antibody; Arbitrary concentration; Autoantibodies; Autoantibody; C diphtheriae; Diphtheria; Diptheria; EIA; ELFA; ELISA; Enzyme immunoassay; IAA; ID; Infectious Disease; InfectiousDisease; MEIA; Microbiology; Point in time; QNT; Quan; Quant; Quantitative; Random; Serum; SR; SUDS; UniversalLabOrders

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

C. diphtheriae Ab IA Qn (S)Corynebacterium diphtheriae Ab [Units/volume] in Serum by ImmunoassayC diphtheriae Ab Ser IA-aCncCorynebacterium diphtheriae AbMICROCorynebacterium diphtheriae antibody, BloodACnc

Frequently asked questions

Code details

Code5116-9

SystemLOINC

Display nameC. diphtheriae Ab IA Qn (S)

DescriptionCorynebacterium diphtheriae Ab

Short nameC diphtheriae Ab Ser IA-aCnc

ComponentCorynebacterium diphtheriae Ab

PropertyACnc

TimingPt

System (specimen)Ser

ScaleQn

MethodIA

ClassMICRO

Example unitsIU/mL;units/mL

StatusACTIVE

Order/ObservationBoth

Flags

BillableNo

Valid clinical useNo

Source

SourceLOINC

Version2.82

Releasemain

First released1.0

Last changed2.73

Consumer names

Corynebacterium diphtheriae antibody, Blood

Part names

Corynebacterium diphtheriae AbACncPtSerQnIAArbitrary ConcentrationPoint in time (spot)SerumImmunoassay

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.