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 50253-4: Fatty acids.nonesterified 1st specimen fasting [Moles/Vol]

Name: LOINC Code 50253-4: Fatty acids.nonesterified 1st specimen fasting [Moles/Vol]
Creator: HealthAssure Clinical Team
Published: 2026-05-21T08:59:34.495Z

50253-4 is a LOINC code used to identify Fatty acids.nonesterified 1st specimen fasting [Moles/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 Fatty acids.nonesterified^1st specimen post CFst. 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 Fatty acids.nonesterified^1st specimen post CFst. 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

Fatty acids.nonesterified [Moles/volume] in Serum or Plasma --1st specimen fasting
Fatty acids.nonesterified^1st specimen post CFst
Acd; Acid; Acute specimen; After; Aliphatic carboxylate C10-C26; Calorie Fast; CHEMISTRY.CHALLENGE TESTING; Fast; Fasting; Fatty acid; FFA; First; Free Fatty Acids; Level; Lipid; NEFA; p fast; PC; Pl; Plasma; Plsm; Point in time; Pre immunization; PST; QNT; Quan; Quant; Quantitative; Random; SerP; SerPl; SerPlas; Serum; Serum or plasma; sp1; sp1 p fast; Spec; SR; Substance concentration

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

Fatty acids.nonesterified 1st specimen fasting [Moles/Vol]Fatty acids.nonesterified [Moles/volume] in Serum or Plasma --1st specimen fastingNEFA sp1 p fast SerPl-sCncFatty acids.nonesterified^1st specimen post CFstCHALFatty acids.nonesterified 1st specimen fasting, BloodSCnc

Frequently asked questions

Code details

Code50253-4

SystemLOINC

Display nameFatty acids.nonesterified 1st specimen fasting [Moles/Vol]

DescriptionFatty acids.nonesterified^1st specimen post CFst

Short nameNEFA sp1 p fast SerPl-sCnc

ComponentFatty acids.nonesterified^1st specimen post CFst

PropertySCnc

TimingPt

System (specimen)Ser/Plas

ScaleQn

ClassCHAL

Example unitsumol/L;mcmol/L; mmol/L

StatusACTIVE

Order/ObservationObservation

Flags

BillableNo

Valid clinical useNo

Source

SourceLOINC

Version2.82

Releasemain

First released2.22

Last changed2.70

Consumer names

Fatty acids.nonesterified 1st specimen fasting, Blood

Part names

Fatty acids.nonesterified^1st specimen post CFstSCncPtSer/PlasQnSubstance 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.