Laboratory Test Information Guide

Details for 25-Hydroxy Vitamin D, Serum

Test Name: 25-Hydroxy Vitamin D, Serum
Alternate Name(s): Calcidiol
25 Vitamin D
25 OH Vitamin D
Laboratory: Endocrinology
Specimen Type: Adult:
5 mL Gold top Vacutainer tube

Pediatric:
0-2 years: 2 x 0.5 mL Red or Gold top Microtainers
2-10 years: 3 mL Red top Vacutainer tube

Light Green top tubes (Li-heparin) or Lavendar top tubes (EDTA) are not acceptable
Collection Information: Minimum volume of serum required is 400 L for adult or pediatric samples.
Requisition: GENERAL LABORATORY REQUISITION
Test Schedule: Monday - Friday
0800-1600
Turnaround time from when specimen
is received in testing laboratory:
 
Routine
5 days
Stat
 
 
Reference Range: Deficiency: < 25 nmol/L
Insufficiency: 25-75 nmol/L
Sufficiency: 75-250 nmol/L
Toxicity: > 250 nmol/L
Effective Date: 2015-04-15
Revised Date: 2018-01-15
Critical Value:  
Interpretive Comments:  
Special Processing:  
Comments: It is common for Canadians to have 25-OH vitamin D levels that are considered insufficient. Choosing Wisely Canada recommends against measurement of 25-OH vitamin D in most patients because routine supplementation with vitamin D is appropriate for the general population. Measurement of 25-OH vitamin D levels should be restricted to patient populations who are more likely to require more aggressive therapy.

Appropriate Indications for 25-OH Vitamin D Testing:

METABOLIC BONE DISORDER (E.g. osteoporosis, osteomalacia, rickets, unexplained bone pain, unusual fractures, prior to initiating bisphosphonate therapy)

MALABSORPTION SYNDROME / SPECIALIZED DIET / HIGH RISK FOR INSUFFICIECY DESPITE SUPPLEMENTATION (E.g. celiac disease, inflammatory bowel disease, pancreatic insufficiency, bariatric surgery, chronic liver disease, total parenteral nutrition)

PERTURBED CALCIUM HOMEOSTASIS (E.g. hypo- or hypercalcemia, hyperphosphatemia, hypo- or hyperparathyroidism)

CHRONIC RENAL FAILURE

THERAPY WITH MEDICATION THAT AFFECTS VITAMIN D LEVEL OR INCREASES RISK OF OSTEOPOROSIS (E.g. long-term steroids, anticonvulsants, HIV medications)

A pop-up with the information above will appear when there is an attempt to order 25-OH vitamin D testing in Cerner. If the individual chooses to proceed with the order, one of these appropriate indications for testing will need to be selected from a subsequent list. The options will be: Bone disorder, Malabs/diet, Abnormal Ca, Renal failure, Meds alter vitD.

For patients who meet one of the indications for 25-OH vitamin D testing, if it is appropriate to re-order the test, please wait at least 90 days before doing so.
Method of Analysis: Diasorin Chemiluminescence
Critical Information Required:  
Storage & Shipment: Store and ship serum frozen.
System Codes: 
Cerner
25VITD
 
Referred To:  

Questions? Comments? Contact Laura Gopaul