Endocrine Pathophysiology - Diabetes Mellitus

Question 1

Type 1 diabetes mellitus

Answer 1

Autoimmune condition which results in the destruction of the pancreatic beta cells resulting in no insulin production

Question 2

Type 2 diabetes mellitus

Answer 2

This occurs when patients gradulally become insulin resistant or when the pancreatic beta cells fail to secete enough insulin or both

Question 3

Other causes of diabetes melllitus:

Answer 3

• chronic pancreatitis
• gestational diabetes mellitus
• cystic fibrosis

Question 4

Diabetes diagnostic investigations:

Answer 4

• Fasting plasma glucose: >7 mmol/L
• Random plasma glucose (plus DM symptoms): >11.1 mmol/L
• HbA1c: >6.5% (48 mmol/mol)

Question 5

General signs and symtoms of diabetes mellitus

Answer 5

• polyuria
• polyphagia
• polydipsia
• blurred vision
• glycosuira
• signs of macrovascular and microvascular disease

Question 6

Signs and symptoms of diabetes mellitus specific to type 1

Answer 6

• acetone breath
• weight loss
• Kussmaul breathing
• nausea and vomiting

Question 7

Complications of diabetes mellitus

Answer 7

• Macrovascular
  
  • hypertension, increased risk of stoke, myocardial infarction, diabetic foot
• Microvascualr
  
  • nephropathy, peripheral neruopathy, retinopathy, erectile dysfunction
• Psychological
  
  • deprssion

Question 8

Who does Phil LOVE the most?

Answer 8

1. God (Obviously :P)
2. Bethany Mary Louise Houston (favourite most loved human by Phil!!!)

Question 9

What is diabetes insipidus?

Answer 9

A disorder caused by low levels of or insensitvity to antidiuretic hormone (ADH) leading to polyuria. This can be cranial or nephrogenic in origin.

Question 10

Signs and symptoms of diabetes insipidus

Answer 10

• Polydypsia
• Polyuria
• Dehydration

Question 11

Investigations for diabetes mellitus and results if cranial cause

Answer 11

• Plasma osmolarity - increased
• Urine osmolarity - decreased
• Plasma Na+ - increased
• 24h urine volume - >2 litres
• Water deprivation test - urine does not concertrate
• After treatment with desopressin - urine becomes concentrated
• MRI scan - look for abnormality of the pituitary gland eg tumour

Question 12

Investigations for diabetes mellitus and results if nephrogenic cause

Answer 12

• Plasma osmolarity - increased
• Urine osmolarity - decreased
• Plasma Na+ - increased
• 24h urine volme - >2 litres
• Water deprivation test - urine does not concertrate
• After treatment with desmopressin - urine does not concentrate

Question 13

Treatment for diabetes insipidus

Answer 13

• Cranial cause
  
  • Desmopressin
• Nephrogenic cause
  
  • High dose desmopressin
  • Correction of electrolyte imbalances
  • Thiazide diuretics
  • Prostaglandin synthase inhibitors
• Surgical
  
  • Excision of tumour if indicated