LOINCActiveBoth

LOINC Code 104478-3: T. pallidum index (S+CSF) [Relative ratio]

104478-3 is a LOINC code used to identify T. pallidum index (S+CSF) [Relative 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 Treponema pallidum index. It is commonly used with the system or sample type Ser+CSF.

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 Treponema pallidum index. It is commonly used with the system or sample type Ser+CSF.

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

What it does not mean

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

Key facts

  • Treponema pallidum ITpA-index [Relative Ratio] in Serum and CSF
  • Treponema pallidum index
  • Both serum and cerebrospinal fluid; Cerebral spinal fluid; Cerebrospinal Fl; ITpA-Index; Microbiology; Point in time; QNT; Quan; Quant; Quantitative; Random; Relative ratio; Serum; Spinal Fl; Spinal Fld; Spinal Flu; Spinal Fluid; SR; Syphilis; T palldm; T pallidum; Treponemal

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

T. pallidum index (S+CSF) [Relative ratio]Treponema pallidum ITpA-index [Relative Ratio] in Serum and CSFITpA-Index Ser+CSFTreponema pallidum indexMICROTreponema pallidum index, Serum+Cerebrospinal fluidRelRto

Frequently asked questions

Code details

Code104478-3
SystemLOINC
Display nameT. pallidum index (S+CSF) [Relative ratio]
DescriptionTreponema pallidum index
Short nameITpA-Index Ser+CSF
ComponentTreponema pallidum index
PropertyRelRto
TimingPt
System (specimen)Ser+CSF
ScaleQn
ClassMICRO
Example unitsratio
StatusACTIVE
Order/ObservationBoth

Flags

BillableNo
Valid clinical useNo

Source

SourceLOINC
Version2.82
Releasemain
First released2.77
Last changed2.78

Consumer names

Treponema pallidum index, Serum+Cerebrospinal fluid

Part names

Treponema pallidum indexRelRtoPtSer+CSFQnRelative RatioPoint in time (spot)Serum and CSF

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 104478-3 | HealthAssure