What does this LOINC code represent?

This LOINC code identifies a lab observation, measurement, question, or clinical concept in a standardized format.

Is this enough to understand my test result?

No. The code identifies the test or observation, but the interpretation depends on the actual result, reference range, and clinical context.

LOINCActiveBoth

LOINC Code 2183-2: Cytochrome B5 reductase (S) [Catalytic activity/Vol]

Name: LOINC Code 2183-2: Cytochrome B5 reductase (S) [Catalytic activity/Vol]
Creator: HealthAssure Clinical Team
Published: 2026-05-25T17:13:11.347Z

2183-2 is a LOINC code used to identify Cytochrome B5 reductase (S) [Catalytic activity/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 Cytochrome B5 reductase. It is commonly used with the system or sample type Ser.

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 Cytochrome B5 reductase. 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: Both

What it does not mean

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

Key facts

Cytochrome B5 reductase [Enzymatic activity/volume] in Serum
Cytochrome B5 reductase
B5 Reductase, NADH-Cytochrome; Catalytic Concentration; Chemistry; CyB5 Reduct; cyt; Methemoglobin reductase; NADH Cytochrome B5 Reductase; NADH Methemoglobin Reductase; NADH-Cytochrome B5 Reductase; Point in time; QNT; Quan; Quant; Quantitative; Random; Serum; 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.

Related SNOMED CT concepts

705114005SNOMED CT mapping for Cytochrome B5 reductase (S) [Catalytic activity/Vol] (2183-2)

Related observations and tests

SNOMED_CT 705114005high

LOINC Code System

Source: LOINC-SNOMED cooperation package

Common synonyms

Cytochrome B5 reductase (S) [Catalytic activity/Vol]Cytochrome B5 reductase [Enzymatic activity/volume] in SerumCyB5 Reduct Ser-cCncCytochrome B5 reductaseCHEMCytochrome B5 Reductase, BloodCCnc

Frequently asked questions

Code details

Code2183-2

SystemLOINC

Display nameCytochrome B5 reductase (S) [Catalytic activity/Vol]

DescriptionCytochrome B5 reductase

Short nameCyB5 Reduct Ser-cCnc

ComponentCytochrome B5 reductase

PropertyCCnc

TimingPt

System (specimen)Ser

ScaleQn

ClassCHEM

Example unitsarb U/L

StatusACTIVE

Order/ObservationBoth

Flags

BillableNo

Valid clinical useNo

Source

SourceLOINC

Version2.82

Releasemain

First released1.0

Last changed2.68

Consumer names

Cytochrome B5 Reductase, Blood

Part names

Cytochrome B5 reductaseCCncPtSerQnCatalytic ConcentrationPoint 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.