Endocrine Flashcards Preview

Fasting: 72 – 100 mg/dl (4.0 – 5.7 mmol/L)

Random: < 180 mg/dl (10 mmol/L)

– Pancreatic disease

– Hormonal antagonists to insulin (eg, cortisol,

growth hormone, catecholamines)

– Drug - &chemical-induced

– Genetic syndromes: Down’s, turner’s

after delivery

caused by immune- mediated destruction of the pancreas

concordance between monozygotic twins is 40%

– association with

HLA-DR3  

DR4/DQA1

DQB1

Association with viruses: coxsackie B4, Rubella, Mumps

and some drugs and toxins

To destroy insulin Rub your Mumps b4 you get kicked in your coxsackie

islet cell antibodies (ICA), other antibodies against pancreatic components and infiltration of the pancreatic islets by T-cells

– There is a long pre-diabetic phase during which the destruction of Beta cells continues

viral or chemical attack on beta cells, leading to exposing new proteins or due to molecular mimicry between viral and beta cell structures. The HLA system is relevant because it is involved in antigen presentation.

– stronger than Type 1 - (80 % concordance in identical

twins).

– no HLA associations

– typically a polygenic disorder: depends on the simultaneous presence of several genes but environmental factors (eg obesity) are involved

– Obesity is associated with around 80% of patients with Type 2 DM.

– More than half of patients with diabetes have BMI between 25 – 29 kg/m2

– Relative risk (RR) for DM for BMI >35kg/m2 100- fold than BMI <22 kg/m2

– DM is rare at BMI 21-22

Increased production of insulin antagonists, such as fatty acids and tumour necrosis factor (TNF) by adipose

tissue, specially in central obesity

– selective destruction of insulin-secreting beta cells.

– insulitis, a chronic inflammatory infiltrate of the islets affecting primarily insulin containing islets.

– Moderate reduction islet tissue

– Variable degrees of deposition of amyloid

– Including : nephropathy, neuropathy, eye disease, heart disease, stroke and problems of feet.

• Hyperglycaemia: • Glycosuria

• Ketoacidosis

• Ketonuria

• Hyperlactatemia

• Hyperlipidemia

• Hypovolemia

• Hyperosmolarity

• A1c > 6.5% OR

• Fasting plasma glucose (FPG) level > 126 mg/dL (7 mmol/L) OR

• Two-hour plasma glucose > 200 mg/dL (11.1 mmol/L) during an oral glucose tolerance test (OGTT)

OR

• Classical signs and symptoms (polyuria, polydipsia and unexplained weight loss), plus random glucose level > 200 mg/dL (11.1 mmol/L)

– Patient fasts overnight

– Take basal glucose level

– Give 75 gram glucose and measure blood glucose level at 120 minutes

– A fasting plasma glucose above normal and below the diabetic range i.e. FPG > 100mg/dl but < 126 mg/dl (between 5.6 mmol/L and 6.9 mmol/L)

– A 2-h value in the OGTT of > 140 mg/dl but < 200

mg/dl (between 7.8 and 11.1 mmol/L, during an OGTT)

5.7–6.4%

• 10 -25% of Western populations are IGT or IFG

• 4 - 9% annual conversion of prediabetic state to clinical diabetes

• It is possible to prevent this conversion by

encouraging weight loss through diet, exercise

and medications

Hemoglobin reacts with glucose non-enzymatically to produce HbA1. HbA1c is the major fraction of glycosylated hemoglobin ( about 5% of total hemoglobin concentration ). HbA1c levels give an integrated measure of glucose concentrations over the previous 2 -3 months

• Hypoglycemia

– Is a complication of diabetes treatment • Diabetic ketoacidosis

• Hyperosmolar nonketotic coma

• Lactic acidosis

– Infection or acute illness

– Trauma

– Emotional disturbance

– Missed insulin dose

• Acute insulin deficiency, and the rise in stress hormones levels lead to progressive hyperglycaemia; severe hyperglycemia cause a huge osmotic diuresis and gross dehydration.

• Acute insulin deficiency and the rise in levels of stress hormones (due to cellular starvation and hypovolemia) lead to development of ketosis. Ketosis cause vomiting.

• Electrolyte disturbance is caused by (i) insulin deficiency (ii) osmotic diuresis (iii)vomiting

• Acidosis is caused by (i) ketosis (ii) lactic acidosis, caused by dehydration and vasoconstriction by stress hormones.