Related Experiment Video
Updated: Jul 20, 2025

A Method of Trigonometric Modelling of Seasonal Variation Demonstrated with Multiple Sclerosis Relapse Data
Published on: December 9, 2015
Pediatric vitamin D: Pseudo-hypervitaminosis
Lily Olayinka1,2, Izmarie Poventud-Fuentes1,2, Emily Garnett1,2
1Department of Pathology and Immunology, Baylor College of Medicine, Houston, Texas, USA.
Background:
Vitamin D toxicity is rare in pediatric population. Falsely elevated levels of 25-hydroxyvitamin D have been reported as a major challenge with immunoassay methods for quantifying vitamin D metabolites.
Case Presentation And Method:
Here, we present two pediatric cases of falsely elevated 25-hydroxyvitamin D that resulted in unnecessary further testing. We also report significant same-day variation in the measurement of 25-hydroxyvitamin D using the Abbott i2000SR immunoassay. Samples were spun twice and their values were confirmed with the gold standard liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for confirmation.
Conclusion:
The addition of a centrifugation step prior to sample testing resolved the variation observed in the measurement of 25-hydroxyvitamin D levels. The patient samples were confirmed with instruments from a different vendor and LC-MS/MS. Re-centrifugation of samples resolved the variation in the 25-hydroxyvitamin D values.
Related Concept Videos
Role of Skin in Vitamin D Synthesis
The solar UV B rays (290-315 nm) are absorbed by the skin, and 7-dehydrocholesterol (provitamin D3) photolyzes it to previtamin D3, which undergoes a rapid transformation to vitamin...
Vitamins
Role of Vitamins in Maintaining Bone Health
Vitamin A
Vitamin A is involved in the process of bone remodeling. Retinoic acid, the active metabolite of Vitamin A, has nuclear receptors in osteoblasts and osteoclasts, which are involved in bone remodeling.
Vitamin B12
Vitamin B12 acts as a cofactor during the formation of osteoblast-related proteins, such as osteocalcin. Vitamin B12 plays a role...
Introduction to Electrolytes
Role of Sodium
One...
Bone Disorders
Bone deposition is also affected by the levels of sex hormones like estrogen and testosterone that promote osteoblast activity and bone matrix synthesis. When the level of these hormones decreases due to aging, it causes a reduction in bone deposition. As a result, bone resorption by osteoclasts...
Pedigree Analysis

