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.

LOINCActiveObservation

LOINC Code 33421-9: ALP Other [Catalytic activity/Vol]

Name: LOINC Code 33421-9: ALP Other [Catalytic activity/Vol]
Creator: HealthAssure Clinical Team
Published: 2026-05-25T17:13:11.347Z

33421-9 is a LOINC code used to identify ALP Other [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 Alkaline phosphatase.other fractions. It is commonly used with the system or sample type Ser/Plas.

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 Alkaline phosphatase.other fractions. 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

Alkaline phosphatase.other fractions [Enzymatic activity/volume] in Serum or Plasma
Alkaline phosphatase.other fractions
Alk; Alk phos; Alkaline phos; Alkaline phosphatase.total; ALKP; ALP; ALP Other; AP; Catalytic Concentration; Chemistry; Frac; Fract; Fraction; Fractionated; Fractionation; Othr; Phos; Phosphtase; Pl; Plasma; Plsm; Point in time; QNT; Quan; Quant; Quantitative; Random; SerP; SerPl; SerPlas; Serum; Serum or plasma; 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 ALP Other [Catalytic activity/Vol] (33421-9)

Related observations and tests

SNOMED_CT 705114005high

LOINC Code System

Source: LOINC-SNOMED cooperation package

Common synonyms

ALP Other [Catalytic activity/Vol]Alkaline phosphatase.other fractions [Enzymatic activity/volume] in Serum or PlasmaALP Other SerPl-cCncAlkaline phosphatase.other fractionsCHEMOther alkaline phosphatase, BloodCCnc

Frequently asked questions

Code details

Code33421-9

SystemLOINC

Display nameALP Other [Catalytic activity/Vol]

DescriptionAlkaline phosphatase.other fractions

Short nameALP Other SerPl-cCnc

ComponentAlkaline phosphatase.other fractions

PropertyCCnc

TimingPt

System (specimen)Ser/Plas

ScaleQn

ClassCHEM

Example unitsarb U/L

StatusACTIVE

Order/ObservationObservation

Flags

BillableNo

Valid clinical useNo

Source

SourceLOINC

Version2.82

Releasemain

First released2.09

Last changed2.73

Consumer names

Other alkaline phosphatase, Blood

Part names

Alkaline phosphatase.other fractionsCCncPtSer/PlasQnCatalytic 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.