Magnesium

Question 1

Deficiency of magnesium caused by

Answer 1

Malnutrition
Malabsorption
Renal loss
Endocrinological disturbances

Question 2

Complications associated with decreased magnesium concentrations are

Answer 2

Neuromuscular irritability (tremor, seizures)
Cardiac symptoms (Tachycardia and arrhythmia)

Question 3

Decreased magnesium concentrations are often related to

Answer 3

Decreased calcium and potassium levels, taking into account that hypomagnesemia may be the primary cause of hypocalcemia.

Question 4

Elevated magnesium values can be observed in

Answer 4

Dehydration
Renal disorders
After intake pf excessive amounts of antacid and can be associated with weakness of reflexes and low blood pressure

Question 5

Method

Answer 5

Photometric test using xylidyl blue

Question 6

Principle

Answer 6

Magnesium ions form a purple colored complex with xylidyl blue in alkaline solution. In presence of GEDTA, which complexes calcium ions, the reaction is specfic. The intensity of the purple color is proportional to the magnesium concentration.

Question 7

Reagent:

Answer 7

Ethanolamine pH 11.0
GEDTA (Glycoletherdiaminetetraacetic acid)
Xylidyl blue

Question 8

Reagent contains

Answer 8

Ethanolamine.

Question 9

Specimen

Answer 9

Serum, plasma, cerebrospinal fluid (CSF) or urine

Question 10

Conversion factor

Answer 10

0.4114 = Magnesium [mmol/L]

Question 11

Reference Range

Answer 11

Serum/Plasma:
Neonates - 1.2 - 2.6 mg/dL (0.48 - 1.05 mmol/L)
Children - 1.5 - 2.3 mg/dL (0.60 - 0.95 mmol/L)
Women - 1.9 - 2.5 mg/dL (0.77 - 1.03 mmol/L)
Men - 1.8 - 2.6 mg/dL (0.73 - 1.06 mmol/L)

Urine: 73 - 122 mg/24 h - (3 - 5 mmol/24 h)
CSF: 2.1 - 3.3 mg/dL (0.85 - 1.35 mmol/L)

Question 12

Wavelength

Answer 12

520 nm (Increased)
628 nm (Decreased)