LOINCObservation

LOINC Code 17644-6: S. pneumoniae 9 Ab 1st specimen/2nd specimen IA (S) [Ratio]

17644-6 is a LOINC code used to identify S. pneumoniae 9 Ab 1st specimen/2nd specimen IA (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 Streptococcus pneumoniae 9 Ab^1st specimen/2nd 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 Streptococcus pneumoniae 9 Ab^1st specimen/2nd 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: DEPRECATED
  • Order vs observation: Observation
  • Method: IA

What it does not mean

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

Key facts

Deprecated Streptococcus pneumoniae 9 Ab [Ratio] in Serum by Immunoassay --1st specimen/2nd specimen
Streptococcus pneumoniae 9 Ab^1st specimen/2nd specimen
12; ABS; Aby; Acute specimen; Antby; Anti; Antibodies; Antibody; Autoantibodies; Autoantibody; Convalescent; EIA; ELFA; ELISA; Enzyme immunoassay; First; IAA; ID; Infectious Disease; InfectiousDisease; MEIA; Microbiology; Pneu; pneum; Pneumo; Pneumococ; Pneumococcal; Pneumococcal pneumonia; Pneumococcus; Pneumon; Pneumonia; Point in time; Post immunization; Pre immunization; QNT; Quan; Quant; Quantitative; Random; Ratios; Rto; S pneum9; S pneumo; S pneumoniae; Second; Serum; sp1; sp2; Spec; Spn; SR; Strep; Strept; Streptococcus pneumoniae 9n; SUDS

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

S. pneumoniae 9 Ab 1st specimen/2nd specimen IA (S) [Ratio]Deprecated Streptococcus pneumoniae 9 Ab [Ratio] in Serum by Immunoassay --1st specimen/2nd specimenDeprecated S pneum9 Ab 1:2 Ser IA-RtoStreptococcus pneumoniae 9 Ab^1st specimen/2nd specimenMICROStreptococcus pneumoniae 9 antibody 1st specimen/2nd specimen, BloodRatio

Frequently asked questions

Code details

Code17644-6
SystemLOINC
Display nameS. pneumoniae 9 Ab 1st specimen/2nd specimen IA (S) [Ratio]
DescriptionStreptococcus pneumoniae 9 Ab^1st specimen/2nd specimen
Short nameDeprecated S pneum9 Ab 1:2 Ser IA-Rto
ComponentStreptococcus pneumoniae 9 Ab^1st specimen/2nd specimen
PropertyRatio
TimingPt
System (specimen)Ser
ScaleQn
MethodIA
ClassMICRO
StatusDEPRECATED
Order/ObservationObservation

Flags

BillableNo
Valid clinical useNo

Source

SourceLOINC
Version2.82
Releasemain
First released1.0l
Last changed2.66

Consumer names

Streptococcus pneumoniae 9 antibody 1st specimen/2nd specimen, Blood

Part names

Streptococcus pneumoniae 9 Ab^1st specimen/2nd specimenRatioPtSerQnIAPoint 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.