LOINCActiveObservation

LOINC Code 58504-2: C peptide 1st specimen post Unsp challenge [Mass/Vol]

58504-2 is a LOINC code used to identify C peptide 1st specimen post Unsp challenge [Mass/Vol] 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 C peptide^1st specimen post XXX challenge. It is commonly used with the system or sample type Ser/Plas.

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 C peptide^1st specimen post XXX challenge. It is commonly used with the system or sample type Ser/Plas.

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

  • C peptide [Mass/volume] in Serum or Plasma --1st specimen post XXX challenge
  • C peptide^1st specimen post XXX challenge
  • Acute specimen; After; CHEMISTRY.CHALLENGE TESTING; Connecting peptide of insulin; First; Level; Mass concentration; p chal; Pept; Pl; Plasma; Plsm; Point in time; Pre immunization; Pro-insulin c peptide; PST; QNT; Quan; Quant; Quantitative; Random; SerP; SerPl; SerPlas; Serum; Serum or plasma; sp1; sp1 p chal; 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 peptide 1st specimen post Unsp challenge [Mass/Vol]C peptide [Mass/volume] in Serum or Plasma --1st specimen post XXX challengeC peptide sp1 p chal SerPl-mCncC peptide^1st specimen post XXX challengeCHALC peptide 1st specimen after challenge, BloodMCnc

Frequently asked questions

Code details

Code58504-2
SystemLOINC
Display nameC peptide 1st specimen post Unsp challenge [Mass/Vol]
DescriptionC peptide^1st specimen post XXX challenge
Short nameC peptide sp1 p chal SerPl-mCnc
ComponentC peptide^1st specimen post XXX challenge
PropertyMCnc
TimingPt
System (specimen)Ser/Plas
ScaleQn
ClassCHAL
Example unitsug/L
StatusACTIVE
Order/ObservationObservation

Flags

BillableNo
Valid clinical useNo

Source

SourceLOINC
Version2.82
Releasemain
First released2.32
Last changed2.73

Consumer names

C peptide 1st specimen after challenge, Blood

Part names

C peptide^1st specimen post XXX challengeMCncPtSer/PlasQnMass ConcentrationPoint in time (spot)Serum or Plasma

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 58504-2 | HealthAssure