LOINCActiveObservation

LOINC Code 27904-2: Histidine (U) [Moles/Vol]

27904-2 is a LOINC code used to identify Histidine (U) [Moles/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 Histidine. It is commonly used with the system or sample type Urine.

Reviewed by HealthAssure Clinical TeamUpdated 25 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 Histidine. It is commonly used with the system or sample type Urine.

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

  • Histidine [Moles/volume] in Urine
  • Histidine
  • Chemistry; Formiminoglutamic Acidemia; His; Histidinemia; Level; Point in time; QNT; Quan; Quant; Quantitative; Random; Substance concentration; UA; UR; Urn

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

Histidine (U) [Moles/Vol]Histidine [Moles/volume] in UrineHistidine Ur-sCncHistidineCHEMHistidine, UrineSCnc

Frequently asked questions

Code details

Code27904-2
SystemLOINC
Display nameHistidine (U) [Moles/Vol]
DescriptionHistidine
Short nameHistidine Ur-sCnc
ComponentHistidine
PropertySCnc
TimingPt
System (specimen)Urine
ScaleQn
ClassCHEM
Example unitsnmol/mL
StatusACTIVE
Order/ObservationObservation

Flags

BillableNo
Valid clinical useNo

Source

SourceLOINC
Version2.82
Releasemain
First released2.00
Last changed2.73

Consumer names

Histidine, Urine

Part names

HistidineSCncPtUrineQnSubstance ConcentrationPoint in time (spot)

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 27904-2 | HealthAssure