LOINCActiveObservation

LOINC Code 51511-4: LDH 2 Elph (CSF) [Catalytic fraction]

51511-4 is a LOINC code used to identify LDH 2 Elph (CSF) [Catalytic fraction] 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 Lactate dehydrogenase 2/Lactate dehydrogenase.total. 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 Lactate dehydrogenase 2/Lactate dehydrogenase.total. 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: Observation
  • Method: Electrophoresis

What it does not mean

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

Key facts

  • Lactate dehydrogenase 2/Lactate dehydrogenase.total in Cerebral spinal fluid by Electrophoresis
  • Lactate dehydrogenase 2/Lactate dehydrogenase.total
  • 2-Hydroxypropanoic acid; 2-hydroxy-propionate; 2-hydroxy-propionic acid; Catalytic Fraction; Cerebral spinal fluid; Cerebrospinal Fl; Chemistry; Dehydrog; Dehyrdogenase; Elec; Elect; Electr; Electro; Electrophhrs; Electrophrs; Elp; Elph; Ep; II; L.D.H; Lact; Lactate dehydrogenase.fraction 2; Lactic acid; Lactic acid dehydrogenase; LD; LD2; LD-2; LDH; LDH isoenzyme 2; LDH2; L-lactate; L-lactate dehydrogenase; Percent; Point in time; QNT; Quan; Quant; Quantitative; Random; Spinal Fl; Spinal Fld; Spinal Flu; Spinal Fluid; Tot; Totl; Tumor marker

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

LDH 2 Elph (CSF) [Catalytic fraction]Lactate dehydrogenase 2/Lactate dehydrogenase.total in Cerebral spinal fluid by ElectrophoresisLDH2 CFr CSF ElphLactate dehydrogenase 2/Lactate dehydrogenase.totalCHEMLDH 2, Spinal fluidCFr

Frequently asked questions

Code details

Code51511-4
SystemLOINC
Display nameLDH 2 Elph (CSF) [Catalytic fraction]
DescriptionLactate dehydrogenase 2/Lactate dehydrogenase.total
Short nameLDH2 CFr CSF Elph
ComponentLactate dehydrogenase 2/Lactate dehydrogenase.total
PropertyCFr
TimingPt
System (specimen)CSF
ScaleQn
MethodElectrophoresis
ClassCHEM
Example units%
StatusACTIVE
Order/ObservationObservation

Flags

BillableNo
Valid clinical useNo

Source

SourceLOINC
Version2.82
Releasemain
First released2.24
Last changed2.70

Consumer names

LDH 2, Spinal fluid

Part names

Lactate dehydrogenase 2/Lactate dehydrogenase.totalCFrPtCSFQnElectrophoresisCatalytic FractionPoint 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.

LOINC Code 51511-4 | HealthAssure