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 90990-3: Protein.monoclonal isotype MS.MALDI-TOF Nom

Name: LOINC Code 90990-3: Protein.monoclonal isotype MS.MALDI-TOF Nom
Creator: HealthAssure Clinical Team
Published: 2026-05-21T09:00:20.875Z

90990-3 is a LOINC code used to identify Protein.monoclonal isotype MS.MALDI-TOF Nom 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 Protein.monoclonal isotype. 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 Protein.monoclonal isotype. 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
Method: MS.MALDI-TOF

What it does not mean

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

Key facts

Protein.monoclonal isotype [Identifier] in Serum or Plasma by MS.MALDI-TOF
Protein.monoclonal isotype
Chemistry; Identity or presence; M Protein; M Protein isotype; M-band; Monoclonal band; Monoclonal spike; M-protein; M-spike; Nominal; Para protein; Paraprotein; Pl; Plasma; Plsm; Point in time; PR; Prot; 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.

Common synonyms

Protein.monoclonal isotype MS.MALDI-TOF NomProtein.monoclonal isotype [Identifier] in Serum or Plasma by MS.MALDI-TOFM Protein isotype SerPl MS.MALDI-TOFProtein.monoclonal isotypeCHEMProtein.monoclonal isotype, BloodPrid

Frequently asked questions

Code details

Code90990-3

SystemLOINC

Display nameProtein.monoclonal isotype MS.MALDI-TOF Nom

DescriptionProtein.monoclonal isotype

Short nameM Protein isotype SerPl MS.MALDI-TOF

ComponentProtein.monoclonal isotype

PropertyPrid

TimingPt

System (specimen)Ser/Plas

ScaleNom

MethodMS.MALDI-TOF

ClassCHEM

StatusACTIVE

Order/ObservationObservation

Flags

BillableNo

Valid clinical useNo

Source

SourceLOINC

Version2.82

Releasemain

First released2.65

Last changed2.65

Consumer names

Protein.monoclonal isotype, Blood

Part names

Protein.monoclonal isotypePridPtSer/PlasNomMS.MALDI-TOFPresence or IdentityPoint 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.