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.

LOINCActiveBoth

LOINC Code 57391-5: Eosinophils/Leukocytes Manual cnt (Syn fld)

Name: LOINC Code 57391-5: Eosinophils/Leukocytes Manual cnt (Syn fld)
Creator: HealthAssure Clinical Team
Published: 2026-05-25T17:13:11.347Z

57391-5 is a LOINC code used to identify Eosinophils/Leukocytes Manual cnt (Syn fld) 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 Eosinophils/Leukocytes. It is commonly used with the system or sample type Synv fld.

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 Eosinophils/Leukocytes. It is commonly used with the system or sample type Synv fld.

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: Both
Method: Manual count

What it does not mean

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

Key facts

Eosinophils/Leukocytes in Synovial fluid by Manual count
Eosinophils/Leukocytes
Eos; Eosin; Eosino; Eosinophil; Eosins; HEMATOLOGY/CELL COUNTS; Joint aspirate; Joint fld; Joint flu; Joint fluid; Leuc; Leuk; Leukocyte; Lkcs; Manl; Number fraction; Percent; Point in time; QNT; Quan; Quant; Quantitative; Random; SF; SNV; Syn; Syn fl; Synov; Synovial fluid; WBC; WBCs; White blood cell; White blood cells

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 Eosinophils/Leukocytes Manual cnt (Syn fld) (57391-5)

Related observations and tests

SNOMED_CT 705114005high

LOINC Code System

Source: LOINC-SNOMED cooperation package

Common synonyms

Eosinophils/Leukocytes Manual cnt (Syn fld)Eosinophils/Leukocytes in Synovial fluid by Manual countEosinophil NFr Snv ManualEosinophils/LeukocytesHEM/BCEosinophils/White Blood Cells, Synovial fluidNFr

Frequently asked questions

Code details

Code57391-5

SystemLOINC

Display nameEosinophils/Leukocytes Manual cnt (Syn fld)

DescriptionEosinophils/Leukocytes

Short nameEosinophil NFr Snv Manual

ComponentEosinophils/Leukocytes

PropertyNFr

TimingPt

System (specimen)Synv fld

ScaleQn

MethodManual count

ClassHEM/BC

Example units%

StatusACTIVE

Order/ObservationBoth

Flags

BillableNo

Valid clinical useNo

Source

SourceLOINC

Version2.82

Releasemain

First released2.29

Last changed2.79

Consumer names

Eosinophils/White Blood Cells, Synovial fluid

Part names

Eosinophils/leukocytesNFrPtSynv fldQnManual countNumber FractionPoint in time (spot)Synovial fluid

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.