Adrenals and Endocrine Pancreas Flashcards
What conditions can cause adrenal hyperfunction?
- Cushing’s syndrome
- Conn’s syndrome
- Adrenogenital syndrome and congenital adrenal hyperplasia
- Adrenocortical neoplasms
Is cushing’s syndrome more common in males or females?
Females
What are features of Cushing’s syndrome?
- Muscle catabolism
- Fat
- Abnormal collagen maturation (can cause stria)
- Hypertension
- Osteoperosis (absorbing more Ca2+)
- Impaired glucose tolerance
- Hirsutism or gyaenacomastia
- Depression / psychosis
What is hirsutism?
Abnormal male-like hair growth on women
What fraction of Cushing’s syndromes are caused by a primary adrenal neoplasm?
~ 1/6
- 50:50 benign to malignant
What fraction of Cushing’s syndromes are related to ectopic ACTH production?
~ 1/6
- Ectopic ACTH or related peptide
- Often part of a paraneoplastic syndrome e.g SCLC
What are the levels of K+ in Conn’s syndrome?
Low (hypokalaemic)
WHat are the features of Conn’s syndrome?
- Hypokalaemia
- Muscle cramps and weakness
- Metabolic alkalosis
- High aldosterone
- Low renin
What gender is affected more by Conn’s syndrome?
Females (4:1)
What percentage of Conn’s syndrome patients have an adrenal adenoma?
80%
What percentage of Conn’s syndrome patients have bilateral hyperplasia of zona glomerulosa but unkown cause?
20%
What enzyme deficiencies can cause congenital adrenal hyperplasia?
- 21 hydroxylase deficiency (CYP21)
- 11-Beta Hydroxylase Deficiency
How common is congenital adrenal hyperplasia?
1 in 15000
Describe the mechanism of congenital adrenal hyperplasia?
Problems in metabolism where one does not get the negative feedback to stop ACTH so you get a drive and hyperplasia
A malignant tumour in the adrenal gland can come from what tissues?
- Lung
- Breast
- Kidney
- Colon
- Melanoma
- Lymphoma
How common are adrenal adenomas on autopsy?
Very common - though to be as high as 5%
- So often not functional therefore not found in life
- Low malignant potential
- Only treated if functional or malignant
Adrenal carcinoma
- Rare
- Poor outlook
- More often secrete sex steriods (Hirsutism)
- Can be quite large (inches)
- Invasive - other organs, fat
What molecular changes can take place in an adrenal carcinoma?
- Proliferation markers increased
- Mutant p53 protein increased
- IGF II increased
- EGFR increased
What gene mutations may cuase adrenal carcinoma?
- p53
- MEN1 (multiple endocrine neoplasia)
What are molecular changes useful for?
- Identifying familial syndrome
- Possibly distinguishing adenoma from carcinoma
What cells do phaeochromocytomas develop from?
Chromaffin cells
How does phaeochromocytoma usually present?
- Intermittent production of catecholamines
- Hypertension
- Sweating
- Collapse
- Glycosuria
- When sympathetic NS activated - symptoms appear, overload of catecholamines
What percentage of phaeochromocytomas are familail?
20%, may be opart of MEN
What percentage of phaeochromocytomas are malignant?
10% (there is a spectrum of benign to frankly malignant)
