Endocrinology
Browse 97 topics in endocrinology.
Acromegaly
The condition is insidious, with a median delay in diagnosis of 7–10 years . During this period, patients develop significant comorbidities, including hypertension, diabetes mellitus, cardiomyopathy, and obstructive...
Acute Adrenal Crisis
An Acute Adrenal Crisis (Addisonian Crisis) is a life-threatening endocrine emergency resulting from an absolute or rela... MRCP exam preparation.
Acute Intermittent Porphyria (AIP)
AIP is often referred to as a "little imitator" because its symptoms—severe abdominal pain, psychiatric disturbances, and neurological deficits—mimic many common conditions, frequently leading to delayed diagnosis or...
Addison's Disease (Primary Adrenal Insufficiency)
Addison's disease is primary adrenal insufficiency (PAI) caused by destruction or dysfunction of the adrenal cortex, res... MRCP exam preparation.
Addisonian Crisis (Acute Adrenal Insufficiency)
Adrenal crisis presents with hypotension, hyponatraemia, hyperkalaemia, hypoglycaemia, and often hyperpigmentation (in p... ACEM Primary Written, ACEM Primary V
Adrenal Crisis
Adrenal crisis is an acute, life-threatening state of cortisol deficiency that requires immediate recognition and treatm... CICM Second Part exam preparation.
Anorexia Nervosa (Adult)
Anorexia nervosa (AN) is a severe psychiatric disorder characterized by persistent restriction of energy intake leading to significantly low body weight (BMI less than 17.5 kg/m² in adults), an intense fear of gaining...
Autoimmune Polyglandular Syndrome (APS)
Autoimmune Polyglandular Syndromes (APS), also referred to as Autoimmune Polyendocrine Syndromes (APS) or Polyglandular ... MRCP exam preparation.
Calcium Disorders: Hypocalcemia and Hypercalcemia
Calcium gluconate 10% 10-20 mL IV over 10-20 minutes (0.9-1.8 mmol Ca2+)... CICM Second Part Written, CICM Second Part Hot Case exam preparation.
Carcinoid Syndrome
Key Facts Tumour Origin : Midgut NETs (Appendix, Ileum) most common to cause syndrome. Syndrome Appears : Usually only after Liver Metastases (Hepatic first-pass metabolism bypassed). 10% of NET patients develop the...
Carcinoid Syndrome and Neuroendocrine Tumours
Neuroendocrine tumours (NETs) represent a heterogeneous group of neoplasms arising from neuroendocrine cells distributed... MRCP exam preparation.
Charcot Neuroarthropathy
The hallmark of acute Charcot is a red, hot, swollen foot in a patient with peripheral neuropathy, often triggered by minor trauma that goes unnoticed due to sensory loss. This acute inflammatory phase is...
Congenital Adrenal Hyperplasia (CAH)
21-Hydroxylase Deficiency (21-OHD) accounts for 95% of all CAH cases and is the most common cause of: Ambiguous genitalia in genetic females (46,XX) Life-threatening salt-wasting crisis in neonates Primary adrenal...
Conn's Syndrome (Primary Hyperaldosteronism)
Primary Hyperaldosteronism (PA) is the autonomous hypersecretion of aldosterone from the adrenal cortex (zona glomerulosa), leading to suppression of renin. It represents the most common cause of secondary...
Conn's Syndrome (Primary Hyperaldosteronism)
Conn's syndrome, or primary aldosteronism (PA), represents the most common cause of secondary hypertension and potentially curable form of hypertension. First described by Jerome Conn in 1955, it is characterised by...
Cushing's Syndrome
The most common cause worldwide is iatrogenic (exogenous glucocorticoid therapy), seen in patients receiving chronic corticosteroid treatment for inflammatory, autoimmune, or malignant conditions. Endogenous Cushing's...
Cushing's Syndrome
The pathophysiology involves systemic dysregulation of protein and fat metabolism, creating a catabolic state characterized by proximal muscle wasting, skin thinning, and paradoxical central obesity. Diagnostic...
Diabetes Insipidus (DI)
In health, AVP is synthesised in the hypothalamus and released from the posterior pituitary in response to rising plasma osmolality or falling blood volume, promoting water reabsorption in the renal collecting ducts...
Diabetic Foot Ulcer
A Diabetic Foot Ulcer (DFU) is a full-thickness wound below the ankle in a patient with diabetes mellitus, arising from the complex interaction of peripheral neuropathy, peripheral arterial disease, and biomechanical...
Diabetic Ketoacidosis (Adult)
Diabetic Ketoacidosis (DKA) is a life-threatening acute metabolic emergency characterized by the pathognomonic triad of hyperglycemia , ketosis , and metabolic acidosis . It represents a state of absolute or relative...
Diabetic Ketoacidosis (DKA)
Diabetic Ketoacidosis (DKA) is a profound metabolic emergency defined by the biochemical triad of Hyperglycaemia, Ketona... MRCP exam preparation.
Diabetic Nephropathy (Diabetic Kidney Disease)
Diabetic Nephropathy (DN), now comprehensively termed Diabetic Kidney Disease (DKD) , represents the leading cause of Chronic Kidney Disease (CKD) and End-Stage Renal Disease (ESRD) globally, accounting for...
Diabetic Retinopathy
DR progresses through distinct stages: Non-Proliferative Diabetic Retinopathy (NPDR) – subdivided into Background (R1), Pre-Proliferative (R2) – and Proliferative Diabetic Retinopathy (PDR, R3) , characterised by...
Dyslipidaemia and Lipid Management
Dyslipidaemia encompasses a spectrum of lipid abnormalities characterized by elevated low-density lipoprotein cholestero... MRCP exam preparation.
Eating Disorders in Adults
Eating disorders are serious, potentially life-threatening mental health conditions characterised by persistent disturba... MRCPsych exam preparation.
Endocrine Physiology (Adrenal, Thyroid, Pituitary)
Endocrine physiology is fundamental to understanding the stress response in critical illness, metabolic regulation, and ... CICM First Part Written, CICM First
Erectile Dysfunction
Erectile dysfunction (ED) is defined as the persistent or recurrent inability to achieve and/or maintain an erection suf... MRCS exam preparation.
Fanconi Syndrome
The clinical hallmarks include: Renal glycosuria despite normoglycaemia Generalised aminoaciduria Phosphaturia leading to hypophosphataemic rickets/osteomalacia Type 2 (proximal) renal tubular acidosis from...
Gastroparesis
The cardinal symptoms are nausea ( 90%), vomiting (particularly of undigested food hours after eating), early satiety , postprandial fullness , bloating , and abdominal pain . These symptoms are often debilitating and...
Gender Dysphoria (Gender Incongruence)
Gender Dysphoria is the clinical distress caused by a discrepancy between a person's Gender Identity (internally experienced gender) and their Sex Assigned at Birth . The condition is characterized by marked...
Gestational Diabetes Mellitus (GDM)
GDM is distinct from pre-existing diabetes mellitus (Type 1 or Type 2) diagnosed before pregnancy. The condition typically resolves within hours to days of placental delivery, as the primary driver of insulin...
Glucagonoma
Dermatosis – Necrolytic Migratory Erythema (NME) Diabetes Mellitus – usually mild to moderate Deep Vein Thrombosis – hypercoagulable state Depression – neuropsychiatric manifestations
Graves' Disease
Diffuse thyroid hyperplasia (smooth, diffusely enlarged goitre) Graves' Ophthalmopathy (Thyroid Eye Disease) - present in 25-50% of patients Pretibial myxoedema (dermopathy) - rare, less than 5% of cases Thyroid...
Gynaecomastia
Physiological gynaecomastia occurs at three life stages: Neonatal (transplacental maternal oestrogen exposure, resolves within weeks), Pubertal (transient oestrogen-androgen imbalance, affects 60% of boys aged 10-16...
Hashimoto's Thyroiditis
Comprehensive, evidence-based guide to Hashimoto's Thyroiditis covering molecular pathophysiology, autoantibody testing, Levothyroxine management, pregnancy considerations, and complications including thyroid lymphoma.
Hirsutism
Key Facts Definition : Excessive terminal hair growth in androgen-sensitive areas in women, quantified by modified Ferriman-Gallwey score ≥8. Prevalence : 5-15% of women of reproductive age; varies significantly by...
Hormone Replacement Therapy (HRT) Protocols
Hormone Replacement Therapy (HRT), also termed Menopausal Hormone Therapy (MHT) , involves the administration of systemic Oestrogen (with or without Progestogen ) to replace declining ovarian hormones in...
Hypercalcaemia (Emergency)
Hypercalcaemia is a common and potentially life-threatening electrolyte disturbance defined by a corrected serum calcium... MRCP exam preparation.
Hyperosmolar Hyperglycaemic State (HHS)
Unlike Diabetic Ketoacidosis (DKA), HHS develops insidiously over days to weeks, leading to a much more profound fluid deficit (often 10–22 litres). The mortality rate of HHS remains high (15–20%), significantly...
Hyperosmolar Hyperglycaemic State (HHS)
HHS is characterised by a relative insulin deficiency that is sufficient to prevent lipolysis and ketogenesis but insufficient to facilitate glucose utilisation or suppress hepatic gluconeogenesis. This results in...
Hyperosmolar Hyperglycaemic State (HHS)
Hyperosmolar Hyperglycaemic State (HHS, formerly HONK/HHNS) is the most lethal hyperglycaemic emergency with 15-20% mort... ACEM Fellowship Written, ACEM Fellow
Hyperparathyroidism (Adult)
Hyperparathyroidism encompasses a spectrum of disorders characterised by excessive parathyroid hormone (PTH) secretion, ... MRCP exam preparation.
Hyperthyroidism in Adults
Hyperthyroidism is a clinical syndrome characterized by the excessive synthesis and secretion of thyroid hormones (thyro... MRCP, USMLE exam preparation.
Hypoglycaemia - Emergency Management
Hypoglycaemia is a medical emergency defined by the clinical triad of low blood glucose (below 4.0 mmol/L in ED context)... ACEM Primary Written, ACEM Primary V
Hypoglycaemia in Adults
Hypoglycaemia is defined as blood glucose below 4.0 mmol/L (72 mg/dL) and represents one of the most common acute complications of diabetes management. It occurs when glucose delivery or production fails to meet...
Hypokalaemia
Clinical manifestations include muscle weakness, cramps, constipation, polyuria, and cardiac effects ranging from palpitations to ventricular arrhythmias. ECG changes are pathognomonic: U waves, flattened T waves, ST...
Hypomagnesaemia
The most important clinical consequences include life-threatening ventricular arrhythmias (particularly Torsades de Pointes), neuromuscular irritability (tetany, seizures), and electrolyte disturbances that cannot be...
Hypoparathyroidism (Adult)
Hypoparathyroidism is a rare endocrine disorder characterized by insufficient secretion of parathyroid hormone (PTH) from the parathyroid glands, resulting in hypocalcaemia and hyperphosphataemia . Unlike other...
Hypophosphataemia
The most clinically significant scenario is refeeding syndrome , where malnourished or starved patients develop acute, life-threatening hypophosphataemia upon carbohydrate refeeding due to rapid intracellular...
Hypothyroidism in Adults
Hypothyroidism is a common clinical syndrome resulting from a deficiency of thyroid hormones, which leads to a generaliz... MRCP, USMLE exam preparation.
Insulinoma
Over 90% of insulinomas are benign, solitary, and less than 2 cm in diameter . Approximately 5-10% are associated with Multiple Endocrine Neoplasia Type 1 (MEN1) , where they may be multiple. Malignancy occurs in...
Kallmann Syndrome
The condition affects approximately 1 in 8,000 males and 1 in 40,000 females , with a male predominance of 4-5:1. Males typically present with absent pubertal development , micropenis , cryptorchidism , and...
Klinefelter Syndrome
The syndrome results from non-disjunction during parental meiosis, leading to testicular dysgenesis and progressive loss of seminiferous tubule function. The pathognomonic triad comprises hypergonadotropic...
Male Hypogonadism
Classic presentation involves reduced libido, erectile dysfunction, fatigue, and regression of secondary sexual characteristics. However, the clinical picture is highly variable depending on the age of onset...
MEN-1 Syndrome
A comprehensive guide to MEN-1 Syndrome, covering the '3 Ps' (Parathyroid, Pituitary, Pancreas), the genetics of the MEN1 gene, molecular mechanisms, screening protocols, and evidence-based management.
Menopause Management
A comprehensive guide to Menopause management, covering HRT prescribing algorithms (Uterus vs No Uterus), risks (VTE, Breast Cancer), and managing Premature Ovarian Insufficiency.
Metabolic Dysfunction-Associated Steatotic Liver Disease (MASLD)
The global prevalence of MASLD is estimated at 25-30% of the general adult population, with significantly higher rates i... MRCP exam preparation.
Metabolic Dysfunction-Associated Steatotic Liver Disease (MASLD)
Metabolic Dysfunction-Associated Steatotic Liver Disease (MASLD), formerly known as Non-Alcoholic Fatty Liver Disease (N... MRCP exam preparation.
Metabolic Syndrome
The unifying pathophysiological mechanism is Insulin Resistance , predominantly driven by excessive visceral adipose tissue accumulation. This creates a vicious cycle: adipose tissue dysfunction leads to ectopic fat...
Multiple Endocrine Neoplasia Type 2 (MEN 2)
A comprehensive, evidence-based guide to Multiple Endocrine Neoplasia Type 2 syndromes (MEN 2A and 2B), focusing on RET proto-oncogene mutations, genotype-phenotype correlations, prophylactic thyroidectomy timing,...
Myxoedema Coma
Key Facts The "Winter Peak" : Over 90% of cases occur during winter months due to cold-induced stress on minimal thermogenic reserves. The T4-T3 Block : In severe illness, the peripheral conversion of T4 to active T3...
Myxoedema Coma
Myxoedema coma (myxedema crisis) is the extreme decompensated state of hypothyroidism with mortality 20-60% despite inte... ACEM Primary Written, ACEM Primary V
Neonatal Hypoglycaemia
The operational threshold for intervention varies between international guidelines, but the British Association of Perinatal Medicine (BAPM 2017) defines the intervention threshold as less than 2.6 mmol/L (47 mg/dL)...
Non-Alcoholic Fatty Liver Disease (NAFLD / MASLD)
Non-Alcoholic Fatty Liver Disease (NAFLD), recently renamed Metabolic Dysfunction-Associated Steatotic Liver Disease (MA... MRCP Part 2 exam preparation.
Obesity Management
Obesity is a chronic, relapsing, neurohormonal disease characterised by excessive adipose tissue accumulation (Body Mass Index ≥30 kg/m²) that poses significant health risks. It represents one of the greatest public...
Osteomalacia (Adult Rickets)
Osteomalacia is a metabolic bone disease characterised by defective mineralisation of the osteoid matrix in adults, resulting in the accumulation of unmineralised or inadequately mineralised bone. The term derives...
Osteomalacia & Rickets
Osteomalacia and rickets represent a spectrum of metabolic bone disorders characterised by defective mineralisation of b... MRCP exam preparation.
Paget's Disease of Bone
The disease typically affects individuals over 55 years of age and is frequently asymptomatic, discovered incidentally through elevated serum alkaline phosphatase (ALP) or characteristic radiological findings. When...
Paget's Disease of Bone
A comprehensive guide to Paget's Disease of Bone, covering pathophysiology, the 'Cotton Wool' skull appearance, isolated raised Alkaline Phosphatase, bisphosphonate therapy, and complications including osteosarcoma.
Perioperative Diabetes Management: Glycemic Control, Insulin Protocols, and Hypoglycemia Prevention
Diabetes mellitus affects 10-15% of surgical patients , with perioperative hyperglycemia associated with increased morbidity including surgical site infections, delayed wound healing, cardiovascular events, and...
Peripheral Neuropathy
The hallmark of successful management lies in accurate phenotyping : Is it Axonal or Demyelinating? (NCS/EMG distinguishes). Is it Symmetric or Asymmetric? (Systemic vs Local/Vasculitis). Is it Large Fiber or Small...
Phaeochromocytoma and Paraganglioma
Phaeochromocytoma is a rare catecholamine-secreting tumour arising from chromaffin cells of the adrenal medulla. When arising from extra-adrenal sympathetic ganglia (paraganglia), the tumour is termed paraganglioma....
Phaeochromocytoma Crisis
The cornerstone of acute management is alpha-adrenergic blockade FIRST using phentolamine (IV) or phenoxybenzamine (oral), followed only then by beta-blockade to control tachycardia. Beta-blockers administered alone...
Phosphate and Magnesium Disorders in the ICU
Identify and treat underlying cause (refeeding, DKA treatment, diuretics, alcoholism)... CICM Second Part Written, CICM Second Part Hot Case exam preparation
Polycystic Ovarian Syndrome (PCOS)
Polycystic Ovarian Syndrome (PCOS) is the most common endocrine disorder in women of reproductive age, affecting approxi... MRCOG exam preparation.
Polycystic Ovary Syndrome (PCOS)
PCOS is not simply an ovarian disorder but a systemic metabolic condition with far-reaching health implications. Women with PCOS face substantially elevated risks of type 2 diabetes mellitus (4-fold increase),...
Prader-Willi Syndrome (PWS)
Prader-Willi Syndrome (PWS) is a complex multisystem genetic disorder caused by loss of expression of paternally inherit... MRCPCH, FRACP exam preparation.
Premature Ovarian Insufficiency (POI)
Premature Ovarian Insufficiency (POI), previously termed Premature Ovarian Failure (POF), is defined as the loss of norm... MRCOG, USMLE exam preparation.
Primary Hyperaldosteronism
First described by Jerome Conn in 1955 as a syndrome of hypertension, hypokalaemia, and adrenal adenoma, PA was initially considered rare. However, the introduction of the aldosterone-renin ratio (ARR) as a screening...
Primary Hyperaldosteronism (Conn's Syndrome)
Primary Hyperaldosteronism (PA), also known as Primary Aldosteronism or Conn Syndrome (when due to an adenoma), represen... MRCP exam preparation.
Primary Hyperparathyroidism
The condition is usually caused by a solitary parathyroid adenoma (80-85% of cases), though multigland hyperplasia (10-15%) and double adenomas (2-5%) also occur. Parathyroid carcinoma is rare, accounting for less...
Prolactinoma (Adult)
A prolactinoma is a benign monoclonal adenoma arising from lactotroph cells of the anterior pituitary that autonomously ... MRCP exam preparation.
Rickets
While nutritional rickets (vitamin D deficiency) accounts for the majority of cases globally, clinicians must recognize genetic and metabolic forms including hypophosphataemic rickets, vitamin D-dependent rickets, and...
Rickets and Osteomalacia
The underlying aetiology is multifactorial but globally dominated by Vitamin D Deficiency (nutritional rickets/osteomalacia), which remains a significant public health problem despite being entirely preventable....
SIADH (Syndrome of Inappropriate ADH) - Adult
The Syndrome of Inappropriate Antidiuretic Hormone secretion (SIADH) is the most common cause of euvolaemic hyponatraemi... MRCP exam preparation.
Stress Response and Critical Illness
The stress response to critical illness is a coordinated neuroendocrine-metabolic-inflammatory cascade designed for short-term survival. The HPA axis releases cortisol (essential for vascular tone and...
Syndrome of Inappropriate ADH Secretion (SIADH)
The Syndrome of Inappropriate Antidiuretic Hormone Secretion (SIADH), also termed Syndrome of Inappropriate Antidiuresis... MRCP, USMLE exam preparation.
Thyroid Cancer
The vast majority ( 90%) of thyroid cancers are differentiated thyroid cancers (DTC) , comprising papillary and follicular subtypes, which originate from thyroid follicular epithelial cells and retain the ability to...
Thyroid Nodule (Adult)
A thyroid nodule is a discrete lesion within the thyroid gland that is radiologically distinct from the surrounding thyr... MRCP, FRACP exam preparation.
Thyroid Nodules & Goitre
Thyroid nodules are discrete lesions within the thyroid gland that are palpably or radiologically distinct from surrounding thyroid parenchyma. They represent one of the most common endocrine disorders, with a...
Thyroid Storm
Thyroid storm (thyrotoxic crisis) is a rare but life-threatening endocrine emergency characterized by severe, decompensa... MRCP exam preparation.
Turner Syndrome (Child)
Turner syndrome (TS) is a chromosomal disorder affecting phenotypic females, characterised by complete or partial absenc... MRCPCH exam preparation.
Type 1 Diabetes Mellitus
Comprehensive evidence-based guide to Type 1 Diabetes diagnosis, insulin management, technology, and complications
Type 2 Diabetes Mellitus
Type 2 Diabetes Mellitus (T2DM) is a chronic, progressive cardiorenal-metabolic syndrome characterized by hyperglycemia ... MRCP exam preparation.
Type 2 Diabetes Mellitus (Adult)
Type 2 Diabetes Mellitus (T2DM) is a chronic progressive metabolic disorder characterized by chronic hyperglycemia resul... MRCP, USMLE exam preparation.
VIPoma
A VIPoma is an exceptionally rare functional pancreatic neuroendocrine tumour (pNET) that secretes excessive amounts of Vasoactive Intestinal Peptide (VIP). This hormone hypersecretion drives massive fluid and...
Zollinger-Ellison Syndrome
Key Features : Sporadic : 75–80% of cases. Usually solitary pancreatic or duodenal tumours, potentially curable with surgical resection. MEN1-Associated : 20–25% of cases. Multiple gastrinomas, often microadenomas,...