Unit 1: Endocrinology - Diabetes Mellitus

Vocabulary flashcards covering the definition, classification, pathophysiology, diagnostic values, medications, and complications of Diabetes Mellitus.

Diabetes Mellitus

A chronic metabolic disease where there is an absolute (Type 1) or relevant (Type 2) shortage of insulin.

Type 1 Diabetes Mellitus

An auto-immune condition characterized by the destruction or atrophy of pancreatic beta cells, resulting in a lack of effective insulin excretion and requiring insulin for survival.

Type 2 Diabetes Mellitus

A lifestyle-related disease where insulin-sensitive tissues (liver, adipose tissue, skeletal muscles) fail to respond normally to insulin-stimulated glucose uptake, despite potentially normal insulin secretion.

MODY

Mature onset of diabetes in the Young; a form of diabetes that often occurs in young adults under the age of $25$.

Gestational Diabetes Mellitus

Diabetes that occurs only during pregnancy; although it ends after pregnancy, the patient has a high chance of becoming a type 2 diabetic within $10$ years.

Islets of Langerhans

Structures in the pancreas that secrete two hormones, insulin and glucagon, essential for maintaining blood sugar levels.

Insulin

A hormone used to control blood sugar levels by facilitating the carriage of glucose across the cell membrane into the mitochondria to generate energy.

Glucagon

A hormone that stimulates the conversion of glycogen from the liver into glucose (glycogenolysis) when circulating glucose levels decrease.

Glycogenesis

The process, facilitated by insulin, where unused glucose is stored in the liver and muscle cells as glycogen.

Glycogenolysis

The process triggered by a drop in blood glucose where glucagon stimulates the conversion of stored glycogen back into glucose.

Glyconeogenesis

The process where non-carbohydrate substances, such as proteins and lipids, are converted into glucose during starvation when glycogen is depleted.

Polyuria

Increased urination resulting from glucose in the glomerular filtrate exerting an osmotic diuretic effect that draws water into the lumen.

Polydipsia

Increased fluid intake resulting from a dehydration status caused by polyuria.

Polyphagia

Excessive food intake resulting from intracellular glucose deficiency stimulating the appetite.

Hyperglycemia

The condition where circulating glucose increases in the blood due to insulin deficiency or ineffective insulin action.

Normal Blood Glucose Range

A serum blood glucose concentration between $4$ and $6 mmol/l$.

Normal Fasting Blood Glucose

A blood glucose level measured after fasting that is below $6.1 mmol/l$.

Normal Postprandial Blood Glucose

A blood glucose level taken two hours after a meal that is below $7.8 mmol/l$.

Oral Glucose Tolerance Test (GTT)

A diagnostic test involving NPO from $22h00$, a $100 g$ pure glucose drink, and a serum glucose draw $2$ hours later; diabetes is confirmed if the value is above $11 mmol/l$.

HbA1C

A diagnostic marker used to monitor long-term glucose control; elevated levels are indicative of diabetes.

Microvascular Complications

Damage to small blood vessels including Retinopathy, cataracts, and glaucoma (eyes), and Nephropathy (kidney) caused by hyperglycemia.

Macrovascular Complications

Damage to large blood vessels increasing the risk of stroke, cerebrovascular disease (brain), and coronary heart disease (heart).

Peripheral Neuropathy

Nerve damage in the peripheral nervous system resulting in pain or numbness and an inability to feel pain in the extremities, often leading to undetected foot wounds.

Peripheral Vascular Disease

Narrowing of blood vessels leading to reduced blood flow in the legs, which can cause cold extremities and delayed healing of wounds.

Actrapid

A short-acting clear insulin that acts within $30$ minutes, lasts between $4$ and $6$ hours, and is the only insulin that can be administered intravenously.

Protophane

A long-acting insulin usually administered at night that provides slow release over $18$ to $24$ hours.

Actraphane

An intermediate-acting insulin that is a mixture of Actrapid and Protophane, lasting between $8$ and $12$ hours, usually given bi-daily.

Metformin (Glucophage)

A biguanide oral medication that improves insulin sensitivity and decreases intestinal absorption of glucose.

Sulphonylurea

A class of oral medications (e.g., Gliclazide, Glibenclamide) that stimulate the pancreas to excrete more insulin.

Diabetes Keto-acidosis (DKA)

A life-threatening acute metabolic complication where the body breaks down fat too fast due to lack of insulin, resulting in the excretion of acidic ketones.