Rhabdomyolysis, like tumor lysis syndrome, can lead to the release of significant amounts of intracellular magnesium. Milk-alkali syndrome is associated with hypermagnesemia. Hypothyroidism Hypoparathyroidism Neoplasm with skeletal muscle involvement Lithium intoxication can produce associated hypermagnesemia. Hyperkalemia and hypercalcemia often are present concurrently. BUN and creatinine Order renal function tests and calculate creatinine clearance to assess the ability of the kidney to excrete magnesium.
Hypothyroidism is a rare cause of hypermagnesemia.
Check thyroid function tests in the absence of any other good explanation. An ECG and cardiac monitor may show prolongation of the PR interval or intraventricular conduction delay, which are nonspecific findings. Although the effectiveness of dialysis in removing divalent cations is debated, some studies have demonstrated removal of a large amount of magnesium using this modality. Assess the patient's ABCs and stabilize. Intubate if necessary.