Views: 42 Author: Site Editor Publish Time: 2024-07-09 Origin: Site
Vitamin D (VD) is well-known for its role in calcium and bone metabolism, being one of the essential micronutrients for maintaining human health. In recent years, substantial evidence has emerged indicating that VD, as a novel immunoregulatory hormone, not only influences bone and calcium metabolism but also partakes in metabolism and immune regulation through various atypical mechanisms such as antioxidative stress, cell proliferation, differentiation, and apoptosis. VD impacts nearly all body tissues and is closely related to endocrine, autoimmune, and other diseases, demonstrating its multifaceted non-skeletal functions.
In human blood circulation, the primary form of VD is 25-hydroxyvitamin D (25-OH-VD), known for its stability and recognized as a reliable indicator of VD nutritional status. It mainly includes two forms: 25-OH-VD2 and 25-OH-VD3, with 25-OH-VD3 being the predominant form in the blood.
The latest "Vitamin D Disease Prevention Guidelines" published by the Endocrine Society in the United States suggest a correlation between blood levels of 25-OH-VD and various common diseases, including musculoskeletal, metabolic, cardiovascular, malignant, autoimmune, and infectious diseases.
As a cholesterol derivative, 25-OH-VD regulates blood calcium and phosphorus levels and participates in cellular metabolism. Measuring serum 25-OH-VD levels can provide insights into bone metabolism, evaluate bone metabolic status, classify osteoporosis, predict fracture risk, and detect vitamin D toxicity. Consequently, it has become a frontline clinical indicator for proper calcium supplementation and osteoporosis prevention and treatment.
Epidemiological studies have found that VD deficiency may be an independent risk factor for cardiovascular disease mortality. Multiple studies indicate a connection between VD and hypertension, with VD supplementation reducing cardiovascular complications in hypertensive patients. Low serum 25-OH-VD3 levels can increase the incidence of metabolic syndrome, leading to hyperlipidemia, insulin resistance, and hypertension, all high-risk factors for cardiovascular diseases. Each 25 nmol/L increase in serum 25-OH-VD levels corresponds to a 10% reduction in cardiovascular events risk.
According to relevant literature, VD plays a role in the development of certain malignancies. VD deficiency has been observed in patients with breast cancer, colon cancer, prostate cancer, and pancreatic cancer. VD has a preventive effect on colorectal tumors, potentially through direct antitumor actions, immune system influences, and regulation of the gut microbiota.
VD is involved in regulating neurotransmitters and neurotrophic factors. Clinical studies suggest that VD benefits certain neurological and psychiatric diseases through anti-inflammatory, antioxidative, neurotransmitter regulatory, and calcium homeostasis mechanisms. Compared to healthy adults, patients with Alzheimer’s disease and cognitive impairment have significantly lower VD levels. Low VD is associated with cognitive impairment and Alzheimer’s disease. Additionally, low serum 25-OH-VD3 levels are an independent risk factor for cerebrovascular disease in Parkinson's patients and have predictive value. Therefore, VD supplementation can prevent Parkinson’s disease and reduce complications.
VD has a regulatory effect on pancreatic β-cells, which also contain VD receptors. Large-scale randomized clinical trials have shown that VD supplementation at doses of 1600-4000 U/day can control blood glucose levels or reduce the incidence of diabetes.
VD deficiency is common among patients with chronic kidney disease (CKD). The VD status is inversely related to CKD progression. Therefore, guidelines for CKD diagnosis and treatment recommend maintaining VD levels at 30 µg/L or higher.
VD levels are closely related to the development of rheumatoid arthritis. Specific VD receptor expressions have been found in macrophages and joint cartilage cells at rheumatoid arthritis sites.
Routine clinical testing of 25-OH-VD serves two main purposes: detecting VD deficiency and guiding VD supplementation, especially in children, to prevent adverse effects from excessive intake. It effectively monitors VD levels, prevents related diseases, assists in the rational supplementation of VD, and aids in assessing disease conditions and treatment efficacy.
Accurate monitoring of VD status helps determine dietary or supplementary needs and guides calcium supplementation. It aids in diagnosing specific metabolic disorders (osteomalacia, rickets, myopathies, VD excess, and toxicity) and exploring pathophysiology and risk assessment for various conditions (osteoporosis, falls, fractures). VD levels should be regularly monitored in patients taking VD to adjust medication as needed and avoid toxicity.
Screening for blood 25-OH-VD levels is recommended for individuals at risk of VD deficiency and those needing to maintain adequate VD nutrition status.
FiCATM 25-OH-VD is a fluorescence immunoassay (FIA) for quantitative determination of 25-Hydroxyvitamin D (25-OH-VD) in human serum, plasma, and whole blood samples. It is mainly used clinically to assist in the diagnosis of vitamin D deficiency related diseases.
Methodology: Fluorescence immunochromatography analysis technology (FIA)
Specimen: 10μL of serum, plasma or whole blood
Reference Range: 30-100 ng/mL
Linearity Range: 5.0-100.0 ng/mL, linear correlation coefficient (r) ≥0.9900.
Accuracy: the relative deviation is within ±15%.
Storage Temperature: 2°C~30°C
Period of Validity: 24 months
