Endocrine Flashcards
(56 cards)
What is Cushing syndrome?
The clinical manifestation of pathological hypercortisolism from any cause
Exogenous corticosteroid exposure is the most common cause.
What is the most common cause of endogenous Cushing syndrome?
Cushing’s disease, caused by an ACTH-secreting pituitary adenoma
Responsible for 70-80% of cases.
What are some common presentations of Cushing syndrome?
Weight gain with central obesity, facial rounding, plethora, proximal muscle weakness, thinning of the skin
Also includes metabolic complications.
List some metabolic complications associated with Cushing syndrome.
- Diabetes mellitus
- Dyslipidaemia
- Metabolic bone disease
- Hypertension
What should be excluded before testing for Cushing syndrome?
Exogenous corticosteroid use
Name one of the four high-sensitivity tests for hypercortisolism.
Late-night salivary cortisol
Other options include low-dose dexamethasone suppression testing, 24-hour urinary free cortisol, and 48-hour dexamethasone suppression testing.
What should be done if a patient has a positive initial screening test for hypercortisolism?
At least one additional test should be used to confirm hypercortisolism.
What should be measured once endogenous hypercortisolism is confirmed?
Plasma ACTH
If ACTH is suppressed, what should diagnostic testing focus on?
The adrenal glands
If ACTH is not suppressed, what conditions should be sought?
Pituitary or ectopic disease
What is the primary treatment of choice for endogenous Cushing syndrome?
Surgical resection of the pituitary adenoma or adrenal adenoma causing hypercortisolism
What are multiple endocrine neoplasia (MEN) syndromes?
Rare hereditary tumour syndromes characterised by the development of multiple endocrine tumours.
MEN syndromes include MEN1 and MEN2 with distinct characteristics and associated tumours.
What gene is associated with MEN1?
Mutations in the tumour suppressor gene MEN1.
MEN1 is crucial for regulating cell growth and preventing tumour formation.
What is the diagnostic criteria for MEN1?
Patients must have ≥2 MEN1-associated tumours, 1 associated tumour with a 1st-degree relative, or a diagnosed pathogenic mutation of MEN1.
This diagnostic approach helps in early identification and management of the syndrome.
List the endocrine tumours associated with MEN1.
‘3 Ps’
- Parathyroid adenomas
- Pituitary adenomas
- Pancreatic tumours
- Gastrinomas
- Neuroendocrine/carcinoid tumours from bronchial/gastric/thymic origin
- Adrenal cortical tumours
- CNS tumours, including meningiomas
- Thyroid tumours
What are the non-endocrine tumours associated with MEN1?
- Cutaneous tumours
- Lipomas
- Facial angiofibromas
These non-endocrine manifestations can also be significant in the clinical presentation of MEN1.
What is the common association of primary hyperparathyroidism in MEN1?
At least 90% of patients develop primary hyperparathyroidism by 50 years of age.
This statistic highlights the importance of monitoring for hyperparathyroidism in MEN1 patients.
What mutations are involved in MEN2?
RET proto-oncogene mutations.
These mutations lead to the development of medullary thyroid cancer and/or phaeochromocytoma.
What are the subgroups of MEN2?
- MEN2A (Sipple’s syndrome)
- MEN2B
What features are associated with MEN2A?
‘2ps and one M’
- Medullary thyroid cancer
- Phaeochromocytoma
- parathyroid adenomas with hyperparathyroidism
(* Hirschsprung’s disease
* Cutaneous lichen amyloidosis )
MEN2A is characterized by a combination of these features, which can vary among patients.
What features are associated with MEN2B?
‘2 Ms and 1 P’
- Medullary thyroid cancer
- Phaeochromocytoma
- Marfanoid body habitus
(* Mucosal intestinal ganglioneuromatosis )
What defines familial medullary thyroid cancer?
- Family patterns of isolated medullary thyroid cancers
- Pedigrees of multiple carriers > 50 years of age
- No other MEN2 manifestations
This form focuses on isolated occurrences of medullary thyroid cancer without broader MEN2 features.
What is the importance of medical management in MEN syndromes?
Medical management of hormonal hypersecretion is important for symptom control.
Hormonal imbalances can lead to significant health issues if not managed appropriately.
What is the role of surgical intervention in MEN syndromes?
Most tumours require surgical evaluation, though surgical cure is not always possible.
The surgical approach can vary based on tumour type and patient health.
