LOINCActiveObservation

LOINC Code 102643-4: Barley smut IgE RAST (S) [Presence]

102643-4 is a LOINC code used to identify Barley smut IgE RAST (S) [Presence] 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 Ustilago nuda Ab.IgE. 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 Ustilago nuda Ab.IgE. 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: Observation
  • Method: RAST

What it does not mean

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

Key facts

  • Barley smut IgE Ab [Presence] in Serum by Radioallergosorbent test (RAST)
  • Ustilago nuda Ab.IgE
  • ABS; Aby; Allergen; Allergens; ALLERGY TESTING; Antby; Anti; Antibodies; Antibody; Autoantibodies; Autoantibody; Barley smut; Immune globulin E; Immunoglobulin E; Point in time; PR; Radioallergosorbent test; Random; Serum; SmQn; SR; U nuda

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

Barley smut IgE RAST (S) [Presence]Barley smut IgE Ab [Presence] in Serum by Radioallergosorbent test (RAST)Barley smut IgE RASTUstilago nuda Ab.IgEALLERGYBarley smut allergy testPrThr

Frequently asked questions

Code details

Code102643-4
SystemLOINC
Display nameBarley smut IgE RAST (S) [Presence]
DescriptionUstilago nuda Ab.IgE
Short nameBarley smut IgE RAST
ComponentUstilago nuda Ab.IgE
PropertyPrThr
TimingPt
System (specimen)Ser
ScaleSemiQn
MethodRAST
ClassALLERGY
StatusACTIVE
Order/ObservationObservation

Flags

BillableNo
Valid clinical useNo

Source

SourceLOINC
Version2.82
Releasemain
First released2.75
Last changed2.75

Consumer names

Barley smut allergy test

Part names

Ustilago nuda Ab.IgEPrThrPtSerSemiQnRASTUstilago nuda (Barley smut) IgEPresence or ThresholdPoint in time (spot)SerumRadioallergosorbent test (RAST)

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.