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EPIC CODE: LAB1110 Vitamin K1, Serum

Additional Codes

Sunquest:  VITKMM
Mayo:         VITK1
Previously: ARUP 0099225 

Secondary ID


Useful For

Assessing circulating vitamin K1 concentration

Method Name

Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS)

Reporting Name

Vitamin K1, S

Specimen Type


Specimen Required

Patient Preparation: Fasting overnight (12-14 hours) (infants-collect prior to next feeding).

Collection Container/Tube:

Preferred: Red top

Acceptable: Serum gel

Submission Container/Tube: Plastic vial

Specimen Volume: 2 mL

Collection Instructions: Centrifuge and aliquot serum into a plastic vial within 2 hours of collection.

Specimen Minimum Volume

0.75 mL

Specimen Stability Information

Specimen Type Temperature Time Special Container
Serum Refrigerated (preferred) 30 days
  Ambient  30 days
  Frozen  30 days

Reject Due To

Gross hemolysis OK
Gross lipemia Reject
Gross icterus OK

Clinical Information

Vitamin K1, or phylloquinone, is part of a group of similar fat-soluble vitamins in which the 2-methyl-1,4-naphthoquinone ring is common. Phylloquinone is found in high amounts in leafy green vegetables and some fruits (avocado, kiwi). It is a required cofactor involved in the gamma-carboxylation of glutamate residues of several proteins. Most notably, the inactive forms of the coagulation factors prothrombin (factor II), factors VII, IX, and X, and proteins S and C are converted to their active forms by the transformation of glutamate residues to gamma-carboxyglutamic acid (Gla). Other proteins such as those involved in bone metabolism, cell growth, and apoptosis also undergo this Gla transformation. Measurement of vitamin K1 (phylloquinone) in fasting serum is a strong indicator of dietary intake and status.

Reference Values

<18 years: Not established

≥18 years: 0.10-2.20 ng/mL


Low vitamin K1 concentrations in the serum are indicative of insufficiency and poor vitamin K1 status.


Testing of nonfasting specimens or the use of vitamin K1 supplementation can result in elevated serum vitamin K1 concentrations.

Clinical Reference

1. Office of Dietary Supplements: Vitamin K Fact Sheet for Health Professionals. National Institutes of Health; Updated March 29, 2021. Accessed April 22, 2022. Available at

2. Lippi G, Franchini M: Vitamin K in neonates: Facts and myths. Blood Transfus. 2011 Jan;9(1):4-9. doi: 10.2450/2010.0034-10

3. Greer FR: Vitamin K the basics-What's new? Early Hum Dev. 2010 Jul;86 Suppl 1:43-7. doi: 10.1016/j.earlhumdev.2010.01.015

Method Description

Deuterated stable isotope (vitamin K1-d7) is added to a serum sample as an internal standard. Protein is precipitated from the mixture by the addition of ethanol. Vitamin K1 and internal standard are extracted from the resulting supernatant by solid-phase extraction. Vitamin K1 and internal standard are then separated utilizing high-throughput liquid chromatography with analysis on a tandem mass spectrometer equipped with a heated nebulizer ion source using multiple-reaction monitoring.(Unpublished Mayo method)

Day(s) Performed

Monday through Thursday

Report Available

2 to 5 days

Specimen Retention Time

14 days

Performing Laboratory

Mayo Clinic Laboratories in Rochester

Test Classification

This test was developed, and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. This test has not been cleared or approved by the US Food and Drug Administration.

CPT Code Information


LOINC Code Information

Test ID Test Order Name Order LOINC Value
VITK1 Vitamin K1, S 9622-2


Result ID Test Result Name Result LOINC Value
62167 Vitamin K1, S 9622-2

NY State Approved