Selenium (synonym: selenium; Se) is a trace element from the group of semimetals. It is an essential component of food in the form of organoselenium compounds (e.g., selenocysteine). Essential substances are necessary for life, i.e. the body cannot produce them itself.
It is absorbed in the small intestine. It is excreted by the kidneys, but also by the intestines and lungs.An important role of selenium is that of a cofactor in various metabolic processes. It interacts with the enzymes glutathione peroxidase (antioxidant; radical scavenger) and thyroxine-5-deiodinase (deiodination of thyroxine).
The process
Material needed
- Blood serum
- 24 h urine
Preparation of the patient
- Not known
Disruptive factors
- Not known
Normal values children – blood serum
| Age | Normal value in μg/l | Normal value in μmol/l |
| 1st-4th month of life (LM). | 18-64 | 0,2286-0,8128 |
| 5TH-12TH LM | 32-101 | 0,4064-1,2827 |
| Infants | 58-116 | 0,7366-1,4732 |
| School-age children | 69-121 | 0,8763-1,5367 |
Normal values adults – blood serum
| Gender | Normal value in μg/l | Normal value in μmol/l |
| Men | 74-139 | 0,9398-1,7653 |
| Women | 74-139 | 0,9398-1,7653 |
Normal value – urine
| Normal value in μg/l | 5-30 |
| Normal value in μmol/l | 0,0635-0,381 |
Indications
- Suspected selenium deficiency
- Suspicion of selenium poisoning
Interpretation
Interpretation of lowered values
- Alimentary (nutritional)
- Nutrient deficiency due to pure parenteral nutrition (nutrition exclusively through the vein).
- Diseases
- Keshan disease – rare disease that occurs in China and causes muscular dystrophy of the skeletal and cardiac muscles in pregnant women and children.
Interpretation of elevated values
- Exposure in industry, especially electrical, glass and porcelain industries.
- Self-medication
Further notes
- If an undersupply of selenium is suspected, a gluthathione peroxidase measurement in the erythrocytes (red blood cells) is useful.
- With a concomitant vitamin E deficiency, the effects of selenium deficiency are amplified.
- The normal requirement for selenium in women and men is 30-70 µg/d.