DIabetes - Aetiology and Clinical features Flashcards
What are the genetic mutations most closely associated with type I diabetes?
- HLA-DR3-DQ2
- HLA-DR4-DQ8
- Both
What is the cause of type I diabetes mellitus?
Autoimmune destruction of pancreatic beta cells
What autoimmune diseases is type I diabetes associated with?
- Thyroid disease
- Coeliac Disease
- Addison’s disease
- Pernicious Aneamia
What age group does type I diabetes most commonly present in?
Children - peak incidence in adolescence
What is the chance of an identical twin of someone with Type 1 diabetes developing type 1 diabetes?
30-50%
What proportion of diabetes is type II diabetes?
90%
What are thought to be factors which increase the risk of developing type II diabetes?
- Age
- Obesity
- Ethnicity
- Family history
- Low birth weight
- Lack of exercise
- Alcohol excess
What is the metabolic syndrome?
A clustering of at least three of the five following medical conditions
- Abdominal obesity - BMI > 30 or increased waist circ
- High blood pressure - >/= 130/85
- High blood sugar - fasting glucose > 5.6 mmol/L
- High serum triglycerides - > 1.7 mmol/L
- Low HDL levels - <1.03 mmol/L male/<1.29 mmol/L female
It is associated with the risk of developing cardiovascular disease and type 2 diabetes
In essence, what pathophysiologically is occuring in type II diabetes?
Decreased insulin production + increased peripheral insulin resistance
In essence, what pathophysiologically is occuring in type I diabetes?
Insulin production ceases
What are the clinical features of diabetics as an acute presentation?
Classic triad:
- Polyuria
- Polydipsia
- Weight loss
Plus others
- Tiredness
- Blurred visions
- Erectile dysfunction
- Neuropathic pain
- Lethargy
- Frequent infection - thrush, UTI
What are secondary causes of diabetes?
- Steroids
- Pancreas - surgery, trauma, cancer, pancreatic destruction (CF, and haemochromatosis) Haemochromatosis, pancreatitis
- Endocrine - Cushing’s, Acromegaly, Phaeochromocytoma, hyperthyroidism, pregnancy
- Glycogen storage diseases
- Congenital Lipodystrophy
Why do individuals with diabetes get poluria?
Due to the osmotic diuresis that results when blood glucose levels exceed the renal threshold
Why can individuals with diabetes present with polydipsia?
Due to the resulting loss of fluid and electrolytes
Why do individuals present with weight loss in diabetes?
Due to fluid depletion and the accelerated breakdown of fat and muscle secondary to insulin deficiency.