Clin Chem Trace Elements

Samples for trace element

Random urine, 24-hour urine, serum, plasma, WB

Why do we use special containers for trace elements

Because some trace elements are available in the environment

What lab methods do we use for trace elements

Atomic absorption spectroscopy or ICP-MS

Chromium (Cr3+) function

Enhances the action of insulin

Activates insulin receptors

Chromium absorption

Absorbed through small intestine, transported by transferrin

Chromium deficiency

Causes insulin-resistant glucose intolerance, weight loss, neurologic deficits

Cr6+

Industrial carcinogen

Toxic form of chromium

Copper function

Important component of ceruloplasmin, cytochrome c oxidase

Ceruloplasmin binds copper and transports it to liver

Copper absorption

Absorbed through the intestines, binds to albumin and transported to liver

Copper deficiency

Menkes disease: gene mutation affecting copper absorption

Malabsorption syndromes

Copper excess

Wilson disease: autosomal recessive disorder

Copper contamination of food/water

Wilson disease

Elevated LFTs, elevated copper, normal ceruloplasmin

Where does copper accumulate

Liver

Brain

Eyes

Manganese function

Important part of metalloenzymes

Formation of connective tissue, growth, reproduction, CHO and lipid metabolism

Metalloenzymes

Enzymes requiring metals for activity

Manganese absorption

Absorbed in small intestine, bound to albumin and transported to the liver

Protein-bound in liver, travels to other tissues

Manganese excretion

Excreted via bile through the feces

Manganese toxicity

Industrial exposure, severe liver disease (can’t excrete)
Neurologic symptoms similar to parkinson’s

Selenium function

Works with vitamin E as an antioxidant

What do antioxidants do

Prevent oxidation and remove free radicals + reactive oxygen species that can destroy cells and DNA

Severe selenium deficiency

Cardiac myopathy and severe arthritis

Mild selenium deficiency

Thyroid disease, impaired immunity, mood disorders, inflammatory

Zinc function

2nd most common trace element in the body

Cofactor to important enzymes ALP, RNA/DNA polymerases, etc.

Regulates synthesis of steroid, thyroid, and other hormones

Zinc absorption

Absorbed in intestines, bound to albumin and transported to the liver where it is attached to enzymes and proteins

Zinc deficiency

Varied, nonspecific symptoms

Depressed growth with stunting

Increased infections (b/c helps in immune response)

Zinc toxicity

Abdominal pain
Diarrhea

Nausea/vomiting