LOINCObservation

LOINC Code 21364-5: Lemon IgG RAST class (S)

21364-5 is a LOINC code used to identify Lemon IgG RAST class (S) 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 Citrus limon Ab.IgG.RAST class. It is commonly used with the system or sample type Ser.

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 Citrus limon Ab.IgG.RAST class. 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: DEPRECATED
  • Order vs observation: Observation

What it does not mean

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

Key facts

  • Deprecated Lemon IgG Ab RAST class [Presence] in Serum
  • Citrus limon Ab.IgG.RAST class
  • ABS; Aby; Allergen; Allergens; ALLERGY TESTING; Antby; Anti; Antibodies; Antibody; Autoantibodies; Autoantibody; f208; IgG RAST; Immune globulin G; Immunoglobulin G; Lemon; Ordinal; Point in time; PR; QL; Qual; Qualitative; Random; Screen; 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.

Common synonyms

Lemon IgG RAST class (S)Deprecated Lemon IgG Ab RAST class [Presence] in SerumDeprecated Lemon IgG RAST QlCitrus limon Ab.IgG.RAST classALLERGYLemon IgG RAST classPrThr

Frequently asked questions

Code details

Code21364-5
SystemLOINC
Display nameLemon IgG RAST class (S)
DescriptionCitrus limon Ab.IgG.RAST class
Short nameDeprecated Lemon IgG RAST Ql
ComponentCitrus limon Ab.IgG.RAST class
PropertyPrThr
TimingPt
System (specimen)Ser
ScaleOrd
ClassALLERGY
StatusDEPRECATED
Order/ObservationObservation

Flags

BillableNo
Valid clinical useNo

Source

SourceLOINC
Version2.82
Releasemain
First released1.0m
Last changed2.75

Consumer names

Lemon IgG RAST class

Part names

Citrus limon Ab.IgG.RAST classPrThrPtSerOrdPresence or ThresholdPoint 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.

LOINC Code 21364-5 | HealthAssure