LOINCActiveObservation

LOINC Code 47309-0: H. influenzae B IgG 2nd specimen/1st specimen (S) [Ratio]

47309-0 is a LOINC code used to identify H. influenzae B IgG 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 Haemophilus influenzae B Ab.IgG^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 Haemophilus influenzae B Ab.IgG^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

Haemophilus influenzae B IgG Ab [Ratio] in Serum --2nd specimen/1st specimen
Haemophilus influenzae B Ab.IgG^2nd specimen/1st specimen
21; ABS; Aby; Acute specimen; Antby; Anti; Antibodies; Antibody; Autoantibodies; Autoantibody; Convalescent; First; H flu; H influenza; H influenzae; Haem influ; Haem influ B; Haemoph; HIB; ID; Immune globulin G; Immunoglobulin G; Infectious Disease; InfectiousDisease; Influ; 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

H. influenzae B IgG 2nd specimen/1st specimen (S) [Ratio]Haemophilus influenzae B IgG Ab [Ratio] in Serum --2nd specimen/1st specimenHaem influ B IgG 2:1 Ser-RtoHaemophilus influenzae B Ab.IgG^2nd specimen/1st specimenMICROHaemophilus influenzae B IgG antibody 2nd specimen/1st specimen, BloodRatio

Frequently asked questions

Code details

Code47309-0
SystemLOINC
Display nameH. influenzae B IgG 2nd specimen/1st specimen (S) [Ratio]
DescriptionHaemophilus influenzae B Ab.IgG^2nd specimen/1st specimen
Short nameHaem influ B IgG 2:1 Ser-Rto
ComponentHaemophilus influenzae B Ab.IgG^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 changed2.70

Consumer names

Haemophilus influenzae B IgG antibody 2nd specimen/1st specimen, Blood

Part names

Haemophilus influenzae B Ab.IgG^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.