Differential Diagnosis for Hypotension, Hypokalemia, and Weakness

Single Most Likely Diagnosis

• Primary Aldosteronism (Conn's Syndrome): This condition is characterized by excessive production of aldosterone, leading to hypokalemia (low potassium levels), hypertension is more common but hypotension can occur in certain cases due to the renin-aldosterone axis dysregulation, and muscle weakness due to potassium depletion.

Other Likely Diagnoses

• Cushing's Syndrome: Excess cortisol can lead to hypokalemia, hypertension is more common but hypotension can occur, and muscle weakness. The combination of these symptoms, especially with other signs like weight gain and striae, points towards Cushing's.
• Adrenal Insufficiency (Addison's Disease): Characterized by deficiency of cortisol and aldosterone, leading to hypotension, hypokalemia (less common but can occur due to the complex electrolyte imbalance), and weakness.
• Bartter Syndrome: A rare genetic disorder affecting the kidneys, leading to excessive urinary loss of potassium (hypokalemia), hypotension, and muscle weakness due to electrolyte imbalances.

Do Not Miss Diagnoses

• Pheochromocytoma with Paraganglioma: Although typically associated with hypertension, a rare presentation could include hypotension, especially if there's significant intravascular volume depletion. Hypokalemia and weakness could also be present due to the effects of excessive catecholamines on the body.
• Toxicity from Certain Medications (e.g., Diuretics, Beta-Blockers): Overuse or misuse of certain medications can lead to hypotension, hypokalemia, and weakness, making it crucial to review a patient's medication list.

Rare Diagnoses

• Liddle's Syndrome: A rare genetic disorder leading to excessive sodium absorption and potassium secretion in the kidneys, resulting in hypokalemia, hypertension (though hypotension can occur in certain contexts), and muscle weakness.
• Gitelman Syndrome: Similar to Bartter Syndrome, it's a genetic disorder affecting the kidneys, leading to hypokalemia, hypotension, and muscle weakness, but it typically presents later in life.
• Hypokalemic Periodic Paralysis: A condition characterized by episodes of muscle weakness or paralysis associated with hypokalemia, which can be triggered by various factors including certain medications, stress, or dietary changes. Hypotension may not be a primary feature but can occur during episodes of paralysis.