Neurofilament light (NfL) | Cleveland Clinic Laboratories

Neurofilament light (NfL) Print

Test Mnemonic

NFLLCP

CPT Codes

83520 - QTY (1)

Includes

NfL, Plasma

Performing Laboratory

LabCorp

FDA Category

Laboratory Developed Test

Specimen Requirements

Volume	Type	Container	Collect Temperature	Transport Temperature	Special Instructions
1 mL	Plasma	EDTA (Lavender)		Ambient	Patient should avoid biotin consumption for at least 72 hours prior to collection. Separate plasma and transfer to standard aliquot tube.

Minimum Specimen Requirements

Volume	Type	Container	Collect Temperature	Transport Temperature	Special Instructions
0.7 mL

Stability

Environmental Condition	Description
Ambient	14 days
Refrigerated	14 days
Frozen	14 days (3 freeze/thaw cycles)

Days Performed

Varies

Turnaround Time

2 - 4 days

Methodology

Name	Description
Electro Chemiluminescence Immunoassay (ECLIA)

Reference Range

Neurofilament Light Chain, Plasma
Sex	Age From	Age To	Type	Range	Range Unit
	Years	4 Years	Normal	< 1.97	pg/mL
	5 Years	9 Years	Normal	< 1.64	pg/mL
	10 Years	14 Years	Normal	< 1.43	pg/mL
	15 Years	19 Years	Normal	< 1.60	pg/mL
	20 Years	29 Years	Normal	< 1.65	pg/mL
	30 Years	39 Years	Normal	< 1.88	pg/mL
	40 Years	49 Years	Normal	< 2.14	pg/mL
	50 Years	59 Years	Normal	< 3.79	pg/mL
	60 Years	69 Years	Normal	< 4.62	pg/mL
	70 Years	79 Years	Normal	< 7.65	pg/mL
	80 Years	99 Years	Normal	< 11.56	pg/mL

Clinical Info

This test is used for the measurement of the level of Neurofilament Light Chain in plasma. There are significant variations in measured plasma NfL levels among different methods and labs. Care must be taken when interpreting results obtained in different studies. Direct comparisons of absolute values can only be done on the same source fluid (plasma or serum). A rise in NfL is not specific for a specific disease factor and may be caused by both neurodegenerative diseases or a head impact during sports. Results should only be used in conjunction with other clinical information when evaluating patients with neurodegeneration. Due to a lack of specificity to a particular neurodegenerative disease, its role as a diagnostic marker is limited. There are numerous demographic, life style, and comorbidity factors that potentially influence NfL levels in plasma. Variables such as exercise,2 blood volume, body mass index may impact measured plasma NfL levels. NfL levels measured in the morning are more than 10% higher than those measured in the evening. Caution should be taken in interpreting NfL levels when disease treatment induced neurological complications that can potentially impact NfL levels. Plasma NfL levels can be decreased in patients with high immunoglobulin G (IgG) levels. Higher concentrations of NfL may be found in persons with history of stroke, atrial fibrillation, myocardial infarction, chronic kidney disease, pregnancy, and diabetes. Lower concentrations of NfL may be found in individuals who are obese (BMI > or =30).