Diabetes Mellitus Flashcards
(56 cards)
What is diabetes mellitus (DM)?
group of metabolic disorders typified by hyperglycaemia resulting from defects in insulin secretion, insulin action or both. Chronic hyperglycaemia is associated with long-term damage, dysfunction and failure of various organs such as: eyes (retinopathy), kidneys (nephropathy), nerves (neuropathy), heart (CV) and BVs (CVI/MI/ASCVD)
How is DM diagnosed?
Glycated Hb (HbA1c) > 48 mmol/L (7%)
FBG > 7.0mmol/L
OGTT 2 hr blood glucose > 11.1mmol/L
Random blood glucose > 11.1mmol/L in presence of symptoms
List 5 types of Diabetes.
Type 1 Diabetes Mellitus
Type 2 Diabetes Mellitus
Gestational Diabetes Mellitus
Diabetes Mellitus secondary to Pancreatitis
Diabetes Mellitus Secondary to Cushing’s disease/Steroids
MODY
Diabetes Insipidus (Central and Peripheral)
What is T1DM?
insulin-dependent DM caused by immune-mediated ß-cell destruction or idiopathic ß-cell destruction; both may be caused by environmental factors e.g. viral infection. Symptoms present when ≈ 80% ß-cell mass lost
What is the pathophysiology of T1DM?
HLA associations + Autoantibodies (islet cells/insulin/GAD/Tyrosine phosphatases)
List 3 types of autoantibodies you may find in type 1 diabetes mellitus
Anti-insulin
Anti-islet antigens (IA2 and IA2-ß)
Anti-GAD
Anti-Tyrosine Phosphatases
Outline 3 clinical presentation of T1DM.
Polydipsia
Lens change
Nocturia
Polyuria
Polydipsia
Weight loss
Fatigue
(4 T’s: Tired/Thirst/Toilet/Thinning)
Why does osmotic lens change occur in DM?
Sugar is a powerful osmolyte which draws water into the lens ≈ swelling ≈ lens change
How may you assess if a patient is clinically dry?
Blood pressure
Dry oral mucosa
Skin turgor
How do you monitor glucose?
- Blood glucometer: FBG > 7.0mmol/L or OGTT or random > 11.1mmol/L
- Wearable technology e.g. Freestyle Libre - measures interstitial glucose and plots
- Sensor + Pump: Sensor detects ∆s in interstitial glucose then pump adjusts insulin levels
- Glycated haemoglobin (HbA1c): diagnostics + monitoring which measures non-enzymatic glycation of haemoglobin for previous 120 days ≈ 3 months ≈ RBC lifetime whereby HbA1c > 48 mmol/L
What two general formulations are there for insulin therapy?
Insulin can be administered as:
1) a quick release formulation
2) longer/slow-release formulation as a mixture
3) Basal bolus regime
What is the basal bolus regime?
Replicate natural, endogenous physiology by eating, estimating activity levels and calculating amount of insulin then injecting insulin as a basal bolus to keep insulin at constant levels in order to reduce risk of hypoglycaemic periods
What device can be used to automate the basal bolus regime?
Continuous subcutaneous insulin infusion is a sensor measuring interstitial fluid [glucose], relaying the information in feedback to the pump which changes its output of insulin administered subcutaneously
What is T2DM?
metabolic disease of the diabetes mellitus metabolic diseases which is typified by IR, hyperglycaemia, polyuria and polydipsia which is generally presenting in older patients with interplay between genetics and environmental risk factors
What is T2DM the result of?
T2DM is the result of genetic factors and environmental factors
i) Genetic factors:
- Defect of ß-cell
- IR
ii) Environmental factors:
- Obesity: visceral fat distribution
- Stress
- Reduced PA
- Diet
Outline the classical presentation of T2DM.
- Polydipsia
- Polyuria
- Weight gain
- Malaise
- Fatigue
- Infections
- Blurred vision
- Incidental findings: Nephropathy/Neuropathy
What is the main fat depot which differs in volume between normal and T2DM pt?
Visceral fat distribution
What is the progression of T2DM like?
Insulin resistance increases causing plasma insulin to increase along with blood glucose which precipitate symptoms and are raised in diagnosis and then plasma insulin falls sharply as ß-cell failure occurs and blood glucose continues to rise which elicits complications and increases morbidity and mortality
List 5 drugs to treat Diabetes.
Insulin
Sulphonylureas (clorpropamide/glipzide/gliclazide)
Biguanides (Metformin)
a-Glucosidase inhibitors
Thiazolidinediones (Pioglitazone)
GLP-1 agonists (Exanitide)
DPP-4 inhibitors
SGLT2 inhibitors
What are the categories of complications of diabetes mellitus?
1) Acute
- DKA
- Hypoglycaemia
- Other emergencies e.g. MALA, HONK coma
2) Chronic:
i) Microvascular
- Retinopathy
- Nephropathy
- Neuropathy
ii) Macrovascular
- CVD
- ASCCVD
- CVI
What are the clinical features of DKA?
Hyperglycemic + Acidosis
Hyperglycaemia:
- Dehydration
- Polydipsia
- Tachycardia
- Hypotension
- Clouding of consciousness
Acidosis:
- Air hunger (Kussmaul’s respiration)
- Acetone on breath
- Abdominal pain
- Vomiting
What is the ketone body metabolism?
Long term fasting state ≈ ∆ metabolism ≈ catabolic breaking down of skeletal muscle + WAT ≈ AAs + FAs ≈ liver ≈ produce ketone bodies ≈ end organ
List 3 ketones present in DKA.
- Acetoacetate
- Acetate - 3ß-hydroxybutyrate
Which of the following is not actually a ketone body by chemical structure?
A. Acetoacetate
B. Acetate
C. 3ß-hydroxybutyrate
C. 3ß-hydroxybutyrate