Differential Diagnosis for Progressive Muscle Weakness and Hypertension

The patient presents with progressive muscle weakness, consistently elevated blood pressure, and significant hypokalemia (low potassium levels), along with hyperglycemia. These findings guide the differential diagnosis.

• Single Most Likely Diagnosis

  • Primary Aldosteronism (A): This condition is characterized by the excessive production of aldosterone, leading to hypertension, hypokalemia, and sometimes metabolic alkalosis. The patient's consistently elevated blood pressure and significantly low potassium level (2.5 mmol/L) are key indicators of primary aldosteronism. The absence of other symptoms such as headaches or anxiety also aligns with this diagnosis, as primary aldosteronism can present subtly.

• Other Likely Diagnoses

  • Periodic Paralysis (C): Although less likely given the chronic nature of the symptoms, periodic paralysis could be considered due to the significant hypokalemia, which is a hallmark of this condition. However, periodic paralysis typically presents with episodic muscle weakness rather than progressive weakness.
  • Hypothyroidism (D): While hypothyroidism can cause muscle weakness, it does not typically cause significant hypertension or hypokalemia. However, it's a consideration in the differential due to the muscle weakness symptom.

• Do Not Miss Diagnoses

  • Pheochromocytoma (E): Although the patient does not exhibit typical symptoms of pheochromocytoma such as paroxysmal hypertension, headaches, sweating, or tachycardia, this diagnosis is critical not to miss due to its potential for severe, life-threatening complications. The heart rate of 60/min and the absence of other symptoms make this less likely, but it should still be considered.
  • Adrenal Insufficiency (B): Typically presents with hypotension, not hypertension, but in some cases, especially with primary adrenal insufficiency (Addison's disease), there can be fluctuations in blood pressure. The significant hypokalemia and hyperglycemia are not typical for adrenal insufficiency, making this diagnosis less likely.

• Rare Diagnoses

  • Other rare causes of hypertension and muscle weakness, such as Liddle's syndrome or Gordon's syndrome, could be considered but are less likely given the presentation. These conditions are characterized by excessive sodium absorption and potassium wasting in the kidneys, leading to hypertension and hypokalemia, but they are much rarer than primary aldosteronism.
  • Familial hypokalemic periodic paralysis is another rare condition that could present with muscle weakness and hypokalemia but typically has a familial pattern and episodic rather than progressive weakness.

The patient's presentation of progressive muscle weakness, significant hypokalemia, and hypertension, without other systemic symptoms, makes Primary Aldosteronism the most likely diagnosis. However, it's crucial to rule out other potentially life-threatening conditions through appropriate diagnostic testing.