Clinical clues to magnesium deficiency

Area of Science:

• Internal Medicine
• Cardiology
• Neurology

Background:

• Electrolyte imbalances, particularly magnesium and potassium depletion, can manifest with serious cardiac and neurological complications.
• Congestive heart failure and urosepsis can be associated with severe electrolyte disturbances.

Observation:

• Two patients with congestive heart failure presented with prolonged QTc intervals and ventricular arrhythmias, alongside magnesium and potassium depletion.
• A third patient with urosepsis on total parenteral nutrition developed diarrhea, hypocalcemia, hypokalemia, hypomagnesemia, weakness, muscular fasciculations, and athetoid movements.

Findings:

• Magnesium repletion was the sole intervention that resolved the cardiac arrhythmias in the first two patients.
• Magnesium repletion normalized both extracellular and intracellular potassium and magnesium levels, leading to the disappearance of arrhythmias.
• Neurological manifestations and biochemical abnormalities in the third patient resolved after magnesium repletion.

Implications:

• Magnesium plays a critical role in maintaining normal cardiac function and neurological stability.
• Prompt magnesium repletion is crucial for managing complex electrolyte disturbances and their associated clinical manifestations.
• This highlights the importance of monitoring and correcting magnesium levels in patients with critical illnesses and electrolyte depletion.