Test Category: Specialist Biochemistry
Investigation Name:Mass spectrometry 25-Hydroxyvitamin D (serum)
Alias or Abbreviation:Vitamin D, 25-hydroxyvitamin D3, 25-hydroxyvitamin D2
Accreditation:UKAS ISO15189 accredited test: On scope
Intro:
Vitamin D plays an important role in bone metabolism and calcium homeostasis. It may have other roles in immune modulation and development of different disease states. Vitamin D occurs in two forms, cholecalciferol (vitamin D3), which is produced in the skin by action of UV radiation and is present in dairy productions and egg yolk, and ergocalciferol (vitamin D2), a semi-synthetic form, present in foods fortified with vitamin D.Vitamin D deficiency causes rickets in children and osteomalacia in adults, which may present with bone pain, tenderness and myopathy. Individuals with low exposure to sunlight are particularly at risk of vitamin D deficiency, particularly if compounded by dietary deficiency/malabsorption. Vitamin D excess usually occurs as a result of supra-physiological supplementation and may lead to hypercalcaemia and metastatic calcification.
When monitoring treatment for vitamin D deficiency, it is preferable to measure both 25-hydroxyvitamin D3 and D2, as vitamin D2 is less potent, and patients may respond more slowly than expected to treatment. Furthermore, many immunoassay methods for total 25-hydroxyvitamin D significantly under-recover 25-hydroxyvitamin D2.
Pathology Laboratory:Mass Spec Laboratory
Requestable Seperately?Yes
Units:nmol/L
Minimum Sample Volume:Preferred: 250 µL serum/plasma,
absolute minimum: 75 µL
Expected Turnaround Time:7 working days
Sample Type:
Serum, lithium heparin or EDTA plasmaComplex Reference Range:<25 nmol/L Vitamin D deficient >br/>
25-50 nmol/L Vitamin D insufficient
50.1-220 nmol/L Vitamin D sufficient
>220 nmol/L Increased risk of vitamin D toxicity
Collection Conditions / Other Information:Please note that referred in work only is analysed by mass spectrometry.
Internal BCPS samples are analysed for total 25-hydroxyvitamin D by immunoassay on the Architect Alinity analysers
Referred to Another Laboratory?No
Storage Requirements:Store separated plasma/serum at 4 °C prior to dispatch
Posting Address / Requirements:1st class post at ambient temperature
Sandwell Health Campus
Pathology Department,
Specialist Chemistry Laboratory,
Lyndon
B71 4HJ
NPEX / PDF Reporting Available:yes
EQA Scheme:UK NEQAS for Vitamin D
Lead Contact Details:Helen Duce, Principal Clinical Scientist,>br/> Email: h.duce@nhs.net
Email Address For Chasing Results:rwh-tr.bcpsspecialistchemistryenquiries@nhs.net
Site Sample Tested:Sandwell Health Campus
Cost:Please email: bcpspathology.info@nhs.net for further details
Contact Number:Tel: 0121 507 5162
