Related Experiment Video

Updated: May 16, 2026

A Novel Method: Super-selective Adrenal Venous Sampling
06:08

A Novel Method: Super-selective Adrenal Venous Sampling

Published on: September 15, 2017

Hypokalaemia: common but not always benign. Severe, persistent hypokalaemia secondary to ectopic ACTH from a

Muhammad Muzaffar Mahmood1, Kurien John

  • 1Department of Cardiology, Sunderland Royal Hospital, Sunderland, UK. muzafar.mahmood@gmail.com

BMJ Case Reports
|November 16, 2012
PubMed

Hypokalaemia is a common and often benign observation. There is usually an obvious underlying cause for the anomaly. However, hypokalaemia can very rarely be the sole presentation of a more sinister disease. A high index of suspicion and a systematic approach are therefore required to avoid delays in the management, especially in the context of presentation to a medical team. We present a case of a patient with severe and persistent hypokalaemia due to ectopic adrenocorticotropic hormone (ACTH) secretion secondary to a carcinoid tumour. The case report is followed by a brief discussion on the approach to the management of hypokalaemia and additional tests to confirm ectopic ACTH.

Related Concept Videos

Diabetic Ketoacidosis l: Introduction01:25

Diabetic Ketoacidosis l: Introduction

DefinitionDiabetic ketoacidosis (DKA) is an acute, life-threatening complication of diabetes mellitus, characterized by a triad of hyperglycemia (blood glucose >250 mg/dL), ketonemia or ketonuria, and metabolic acidosis (arterial pH <7.30 and serum bicarbonate <18 mEq/L). It results from insulin deficiency combined with elevated levels of counterregulatory hormones—glucagon, catecholamines, cortisol, and growth hormone—leading to increased lipolysis, hepatic ketone production, and...
Cushing Syndrome II: Pathophysiology01:19

Cushing Syndrome II: Pathophysiology

Cortisol production is normally governed by the hypothalamic–pituitary–adrenal (HPA) axis, which maintains hormonal balance through tightly regulated feedback mechanisms. Disruption of this regulatory system is central to the development of Cushing syndrome, whether the excess cortisol originates from external medications or internal pathology. Persistent cortisol elevation alters metabolism, immune function, and endocrine signaling, producing the characteristic clinical features of the...
Cushing Syndrome I: Introduction01:26

Cushing Syndrome I: Introduction

Cushing syndrome refers to the collection of clinical manifestations that arise when tissues are exposed to excessive amounts of cortisol or cortisol-like medications over an extended period. Cortisol, a glucocorticoid produced by the adrenal cortex, regulates metabolism, immune responses, and the body’s adaptation to stress. When its concentration remains chronically elevated, these physiological pathways become dysregulated, resulting in the characteristic features of the syndrome.Exogenous...
Diabetic Ketoacidosis ll: Pathophysiology01:22

Diabetic Ketoacidosis ll: Pathophysiology

Diabetic ketoacidosis (DKA) is a metabolic emergency characterized by hyperglycemia, ketonemia, and metabolic acidosis. It results from severe insulin deficiency and an excess of counterregulatory hormones, leading to uncontrolled lipolysis, ketogenesis, and widespread electrolyte and fluid disturbances.Pathophysiology The central event in DKA is a profound loss of insulin action. Without insulin, glucose uptake in insulin-dependent tissues is impaired, while hepatic glucose production...
Chronic Kidney Disease II: Clinical Manifestations01:24

Chronic Kidney Disease II: Clinical Manifestations

Chronic Kidney Disease (CKD) progressively impairs multiple body systems due to the accumulation of uremic toxins, which disrupt cellular functions across various organs.Neurologic symptomsNeurologic symptoms often arise early in CKD, as uremic toxin buildup drives changes in cognitive and motor functions. Patients frequently experience fatigue, headache, confusion, difficulty concentrating, and, in severe cases, seizures. Peripheral neuropathy commonly manifests as burning sensations in the...
Adrenal Gland Disorders01:27

Adrenal Gland Disorders

Adrenal gland disorders manifest when the production of adrenal hormones deviates from the norm, resulting in either excessive or insufficient concentrations.
Adrenal insufficiency, characterized by insufficient cortisol and aldosterone production, leads to conditions like Addison's disease. This disorder, affecting the adrenal cortex, exhibits symptoms such as skin bronzing, dehydration, low blood pressure, fatigue, and weight loss. Congenital adrenal hyperplasia, a genetic ailment causing...