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Objective: This case report aimed to highlight the prominence of considering Cushing's disease (CD) in the differential diagnosis of severe hypokalemia and metabolic alkalosis.
Case Report: A 63-year-old woman who was admitted to the emergency room with fatigue and severe weakness of extremities. Biochemistry results indicated severe hypokalemia (potassium = 1.2 mmol/L) and metabolic alkalosis (pH = 7.83) and based on further endocrinological investigations, the final diagnosis of CD was confirmed, and magnetic resonance imaging revealed a microadenoma in the right side of the pituitary gland. Transsphenoidal surgery was performed. After surgery, biochemical assessments showed normal potassium levels and corrected metabolic alkalosis without any further treatment. The hypothalamic–pituitary–adrenal axis recovered in nearly eight months and the patient was in remission.
Conclusions: Although hypokalemia could be present in CD, none of the previous studies have reported hypokalemia as severe as in this case. This case report highlighted the prominence of considering CD in the differential diagnosis of severe hypokalemia and metabolic alkalosis that could be a crucial part of biochemical features in CD.
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