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 34637-9: 5-Methyltetrahydrofolate (CSF) [Mass/Vol]

Name: LOINC Code 34637-9: 5-Methyltetrahydrofolate (CSF) [Mass/Vol]
Creator: HealthAssure Clinical Team
Published: 2026-05-25T17:13:11.347Z

34637-9 is a LOINC code used to identify 5-Methyltetrahydrofolate (CSF) [Mass/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 5-Methyltetrahydrofolate. It is commonly used with the system or sample type CSF.

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 5-Methyltetrahydrofolate. It is commonly used with the system or sample type CSF.

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

What it does not mean

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

Key facts

5-Methyltetrahydrofolate [Mass/volume] in Cerebral spinal fluid
5-Methyltetrahydrofolate
5Me-tetrahydrofolate; 5MTHF; Cerebral spinal fluid; Cerebrospinal Fl; Chemistry; Level; Mass concentration; Point in time; QNT; Quan; Quant; Quantitative; Random; Spinal Fl; Spinal Fld; Spinal Flu; Spinal Fluid

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 5-Methyltetrahydrofolate (CSF) [Mass/Vol] (34637-9)

Related observations and tests

SNOMED_CT 705114005high

LOINC Code System

Source: LOINC-SNOMED cooperation package

Common synonyms

5-Methyltetrahydrofolate (CSF) [Mass/Vol]5-Methyltetrahydrofolate [Mass/volume] in Cerebral spinal fluid5Me-tetrahydrofolate CSF-mCnc5-MethyltetrahydrofolateCHEM5-Methyltetrahydrofolate, Spinal fluidMCnc

Frequently asked questions

Code details

Code34637-9

SystemLOINC

Display name5-Methyltetrahydrofolate (CSF) [Mass/Vol]

Description5-Methyltetrahydrofolate

Short name5Me-tetrahydrofolate CSF-mCnc

Component5-Methyltetrahydrofolate

PropertyMCnc

TimingPt

System (specimen)CSF

ScaleQn

ClassCHEM

Example unitsng/mL

StatusACTIVE

Order/ObservationBoth

Flags

BillableNo

Valid clinical useNo

Source

SourceLOINC

Version2.82

Releasemain

First released2.11

Last changed2.42

Consumer names

5-Methyltetrahydrofolate, Spinal fluid

Part names

5-MethyltetrahydrofolateMCncPtCSFQnMass ConcentrationPoint in time (spot)Cerebral spinal 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.