Evaluation of vitamin C deficiency

Lt green plasma separator (PST)

Immediately following collection, mix sample thoroughly by gentle inverting 8 - 10 times to prevent clotting

Protect from light

1. Spin immediately after sample collection
2. Transfer plasma to an  Amber screw-cap polypropylene frozen transport tube/vial - 4mL (LabCorp), labelled as Lithium heparin plasma
3. Freeze within 4 hours of separation

Amber screw-cap polypropylene frozen transport tube/vial - 4mL (LabCorp)

Frozen (strict) - 14 days

Freeze/thaw cycles - stable x 1

Refrigerated - NO

Ambient - NO

• Anticoagulants other than lithium heparin
• Specimen not protected from light

Liquid chromatography-tandem mass spectrometry (LC/MS-MS)

0.4 - 2.0 mg/dL

Serum levels of vitamin C are an adequate measurement of clinical status. Vitamin C is a cofactor for protocollagen hydroxylase; it promotes the conversion of tropocollagen to collagen. Low values occur in scurvy, malabsorption, alcoholism, pregnancy, hyperthyroidism, and renal failure. Smokers have lower levels than nonsmokers. Patients with scurvy have values <0.2 mg/dL.

Principal clinical findings in scurvy include bleeding gums, petechiae, follicular hyperkeratosis, perifollicular hemorrhages beginning on the lower thighs, muscle aches, easy fatiguability, and emotional changes.