Endocrinology Flashcards
What is Bartter’s syndrome?
An inherited form of severe hypokalaemia
What is the underlying fault found in Bartter’s syndrome?
Dysfunction of the Na-K-2Cl-cotransporter (NKCC2) of the ascending Loop of Henle
What is the inheritance pattern of Bartter’s syndrome?
Usually autosomal recessive
What clinical features are associated with Bartter’s syndrome? (5)
1) Failure to thrive
2) Polyuria/Polydypsia
3) Hypokalaemia
4) Normotension
5) Weakness
What is the inheritance pattern of Multiple Endocrine Neoplasia?
Autosomal dominant
What conditions are associated with MEN Type 1? (5)
1) HyperParathyroidism secondary to hyperplasia
2) Pituitary lesions
3) Pancreas lesions (Insulinoma, Gastrinoma)
4) Adrenal
5) Thyroid
What conditions are associated with MEN Type 2?
1) Phaeochromocytoma
2) Parathyroid lesions
3) Medullary thyroid Ca (70%)
What conditions are associated with MEN Type 3?
1) Phaeochromocytoma
2) Marfanoid body habitus
3) Neuromas
What gene is implicated in MEN Type ?
MEN1 gene
What gene is implicated in MEN Type 2?
RET oncogene
What gene is implicated in MEN Type 3?
RET oncogene
What are the causes of primary hyperparathyroidism? (4)
1) Solitary parathyroid adenoma (85%)
2) Parathyroid hyperplasia (10%)
3) Multiple parathyroid adenomas (4%)
4) Parathyroid carcinoma (1%)
What conditions are associated with primary hyperparathyroidism? (2)
1) HTN
2) MEN Type I and II
What are the typical blood results of a patient presenting with primary hyperparathyroidism?
1) High Ca
2) Low PO4
3) Either normal or high PTH
What radiological features are associated with primary hyperparathyroidism? (2)
1) Pepperpot skull
2) Osteitis fibrosa cystica
What is the definitive treatment of primary hyperparathyroidism?
Total parathyroidectomy
In what group of patients can conservative management of primary hyperparathyroidism be considered?
Patient aged >50 w/ Ca <0.25 above upper threshold, and has no end organ damage
What medical management can be implemented for patients with primary hyperparathyroidism when surgery is not an option?
Cinecalcet (allosteric activation of Ca-sensing receptor)
In what two settings would you expect to see carcinoid syndrome?
1) Metastasis of neuroendocrine tumour to the liver, causing release of Serotonin into the systemic circulation
2) Mediators from lung neuroendocrine tumours not being cleared by the liver, thus entering the systemic circulation
What clinical features are associated with Carcinoid syndrome? (7)
1) Flushing (usually first presenting symptom)
2) Diarrhoea
3) Bronchospasm
4) Hypotension
5) R heart valvular stenosis (although L heart valves can be affected in bronchial tumours)
6) Pellagra, due to dietary tryptophan being converted to Serotonin rather than Niacin
7) Cushing’s syndrome secondary to secretion of ACTH/GHRH
What investigations are needed to assess for carcinoid syndrome?
Urinary 50HIAA
Plasma chromogranin Ag
What is the pharmacological treatment for carcinoid syndrome?
Somatostatin analogues, such as Octreotide
