chemical pathology: type 1 & 2 diabetes Flashcards
What is the definition of diabetes
Uncontrolled hyperglycemia due to deficiency insulin action
What is type 1 diabetes
B cell destruction with absolute insulin deficiency
What is type 2 diabetes
Insulin resistance or relative deficiency
What is a general treatment measure for all diabetic patients & why
Exercise & reduce high GI carbohydrates
It decreases insulin requirement
What is three short term complications of diabetes
- Polyuria & polydipsia
- Cerebral dehydration
- Keto-acidosis
Why does polyuria & polydipsia occur
Blood glucose rises extremely high & can not be reabsorbed by renal tubules leading to drawing water into urine leading to osmotic diuresis
Why does cerebral dehydration occur
Glucoses raises osmolality of ECF & drawing water out of cells especially brain
What is the three macrovascular long term consequences of diabetes
- Coronary heart disease
- Peripheral vascular disease
- Stroke
What is the three microvascular long term consequences of diabetes
- Retinopathy
- Nephropathy that can lead to CKD
- Neuropathy
What is the four counter regulatory hormones of blood glucose & their function
- Glucagon: glycogenolysis & gluconeogenesis
- Adrenaline: lipolysis & glycogenolysis
- Growth hormone: lipolysis & glycogenolysis
- Cortisol: proteolysis & gluconeogenesis
What is the regulatory hormone of blood glucose regulation & the functions
Insulin: glycogen synthesis, protein synthesis & fat synthesis
How does insulin secretion work
- Glucose enters the cell causing the potassium channels to close & calcium influx
- Pro-insulin is secreted as a granules via exocytosis
What two endocrinopathies causes diabetes
- Acromegaly
- Cushing syndrome
What drugs can cause diabetes
Glucocorticoids
What is the characteristics of type 1 vs type 2 diabetes in appearance
Type 1: <30 years, lean & otherwise healthy
Type 2: older, obese/overweight with other comobidities
How does type 1 vs type 2 diabetes get diagnosed
Type 1: acute onset, symptomatic & hyperglycemic
Type 2: gradual onset, asymptomatic & diagnosed at routine screening
What is the treatment for type 1 diabetes
Insulin
What is diabetic keto-acidosis
Inappropriate & exaggerated starvation response due to lack of insulin
Explain how diabetic keto-acidosis occur
IMAGE
What is the three distinct symptoms of DKA
- Polyuria, polydipsia,
- Ketones in urine
- Kussmaul breathing due to metabolic acidosis
What is the treatment regimen for DKA
- Restore ECV with bolus saline
- Replace insulin
- Replace potassium, phosphate & magnesium
- Dextrose infusion with insulin when blood glucose reaches 10mmol/L
- Treat infection/educate on use of medication
What triggers DKA
- Infetion
- Poorly controlled
Why is dextrose given in DKA & for how long
Restore glycogen stores
Until all ketones are removes
What is a classic sign of type 2 diabetes
Acanthosis nigricans
Why does Acanthosis nigricans occur
Proliferation of keratinocytes & fibroblasts due to insulin resistance & hyperinsulinemia
What is Acanthosis nigricans
Brown to black hyperpigmentation of skin at body folds
What is the reaction that causes Acanthosis nigricans
Chronically high levels of insulin cross reacts with IGF receptors
What population is at risk for type 2 diabetes
- Obese patients
- Polygenic genetic disposition
- Refined carbohydrate diet that causes chronic hyperinsulinism & adipocyte hypertrophy increasing insulin resistance
What is the treatment for type 2 diabetes
- Diet, exercise & metformin
- Sulfonylureas
- Insulin
What is hyperosmolar hyperglycaemic state
Occurs with type 2 diabetic patients due to insulin levels high enough to prevent ketosis but not to control blood glucose
What is the four complications of HHS
- Severe dehydration
- Intracellular dehydration
- Increased blood viscosity
- Whole body electrolyte loss
What is the treatment for HHS
- Saline bolus
- Insulin
- Electrolyte replacement
What is the four test that can be used for diagnosis & amount
- Random plasma glucose: 11.1mmol/L
- Fasting plasma glucose: 7mmol/L
- 2 hours glucose test: 11.1mmol/L
- HbA1c: 6.5%
What is HbA1c
Glucose binds irreversibly to N terminal of b-chain of the red cells & red cells survive for 120 days therefor long term indicator of glucose levels
What is the three shortfalls of HbA1c
- Shortened erythrocyte lifetime causing false low HbA1c
- Increase erythrocyte lifetime causing false high HbA1c
- Haemoglobinopathies
What is the four population groups that should be screened for diabetes
- > 45 years patients
- Overweight or obese patients
- Gestational visit at week 24-28/women >40years prior pregnancy
- Risk factors: physically inactive, family history, hypertension, PCOS, heart disease history, cholesterol levels high
What is gestational diabetes
Diabetes that occur in pregnancy due to changes in hormone but resolve after delivery
What is the treatment for gestational diabetes
Diet, exercise & insulin
What is the four effects of gestational diabetes on the baby
- Macrosomia with birth complications
- Premature
- Transient hyperinsulinism
- Future risk
What is the three effects of gestational diabetes on the mother
- Pre-eclampsia
- Birth complications
- Future risk
What is the screening method of gestational diabetes
- 50g glucose orally & test after an hour >7.8mmol/L
- Fasting glucose
What is the follow up procedure in diabetes
- Blood pressure & BMI
- Type 1 daily glucose
- HbA1c every 3-6 months <6.5%
- Fundoscopy
- Urinary albumin & creatinine for renal end organ damage
- Plasma creatinine with eGFR
- Lipids
- ECG once a year
- Vaccination
- Assess for neuropathy, diabetic foot & gum disease
