RT Journal Article SR Electronic T1 Refractory hypokalaemia and hypertension with metabolic alkalosis: an acute presentation of Cushing’s disease secondary to a pituitary macroadenoma JF BMJ Case Reports JO BMJ Case Reports FD BMJ Publishing Group Ltd SP e244850 DO 10.1136/bcr-2021-244850 VO 14 IS 8 A1 Najeeb Zaheer Shah A1 Shah Malik A1 Thozhukat Sathyapalan A1 Kamrudeen Mohammed YR 2021 UL http://casereports.bmj.com/content/14/8/e244850.abstract AB A 68-year-old woman presented with right arm cellulitis, not responsive to oral antibiotics. Intravenous antibiotics were commenced, and an ultrasound scan confirmed a collection that was surgically drained. She developed refractory hypokalaemia with normal magnesium, no gastrointestinal losses and no iatrogenic cause. She was hypertensive, hyperglycaemic, alkalotic, clinically obese with proximal myopathy and skin bruising. These clinical findings and refractory hypokalaemic hypertension with metabolic alkalosis raised a suspicion of Cushing’s syndrome (CS). 24-hour urinary free cortisol (24 hours) was grossly raised on two occasions. The adrenocorticotropic hormone (ACTH) was significantly raised at 154 ng/L, confirming ACTH-dependant CS. A CT scan of the thorax, abdomen and pelvis excluded an ectopic source of hypercortisolaemia. MRI pituitary revealed an invasive macroadenoma. Treatment with endoscopic debulking resulted in the resolution of hypokalaemia and metabolic alkalosis with significant improvement in hyperglycaemia and hypertension.