Contact the laboratory when sending a request for vitamin K.
Light sensitive. Protect samples from strong light. Tubes should be placed in dark e.g.wrapped immediately in tin foil. 2 mL serum required, though in neonatal patients 1 mL serum is sufficient.
Ideally collect sample after overnight fast.
PIVKA II (functional marker of Vitamin K status) will normally also be assayed from this sample.
Samples will be stored at -80 Celsius before sending on dry ice to referral laboratory.
Referred to the Human Nutristasis Unit, Guy’s and St Thomas’ Hospital specialist unit.