LOINCActiveObservation

LOINC Code 47298-5: C. diphtheriae Ab 2nd specimen/1st specimen (S) [Ratio]

47298-5 is a LOINC code used to identify C. diphtheriae Ab 2nd specimen/1st specimen (S) [Ratio] 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^2nd specimen/1st specimen. 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^2nd specimen/1st specimen. 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: Observation

What it does not mean

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

Key facts

Corynebacterium diphtheriae Ab [Ratio] in Serum --2nd specimen/1st specimen
Corynebacterium diphtheriae Ab^2nd specimen/1st specimen
21; ABS; Aby; Acute specimen; Antby; Anti; Antibodies; Antibody; Autoantibodies; Autoantibody; C diphtheriae; Convalescent; Diphtheria; Diptheria; First; ID; Infectious Disease; InfectiousDisease; Microbiology; Point in time; Post immunization; Pre immunization; QNT; Quan; Quant; Quantitative; Random; Ratios; Rto; Second; Serum; sp1; sp2; Spec; SR

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 2nd specimen/1st specimen (S) [Ratio]Corynebacterium diphtheriae Ab [Ratio] in Serum --2nd specimen/1st specimenC diphtheriae Ab 2:1 Ser-RtoCorynebacterium diphtheriae Ab^2nd specimen/1st specimenMICROCorynebacterium diphtheriae antibody 2nd specimen/1st specimen, BloodRatio

Frequently asked questions

Code details

Code47298-5
SystemLOINC
Display nameC. diphtheriae Ab 2nd specimen/1st specimen (S) [Ratio]
DescriptionCorynebacterium diphtheriae Ab^2nd specimen/1st specimen
Short nameC diphtheriae Ab 2:1 Ser-Rto
ComponentCorynebacterium diphtheriae Ab^2nd specimen/1st specimen
PropertyRatio
TimingPt
System (specimen)Ser
ScaleQn
ClassMICRO
StatusACTIVE
Order/ObservationObservation

Flags

BillableNo
Valid clinical useNo

Source

SourceLOINC
Version2.82
Releasemain
First released2.19
Last changed2.69

Consumer names

Corynebacterium diphtheriae antibody 2nd specimen/1st specimen, Blood

Part names

Corynebacterium diphtheriae Ab^2nd specimen/1st specimenRatioPtSerQnPoint in time (spot)Serum

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 47298-5 | HealthAssure