Endocrine Disease Pathology Flashcards
Define endocrine gland
One whose secretions (hormones) pass directly into the blood stream
What do hormones influence?
Target organs by binding to receptors - cell surface or intranuclear
Define exocrine gland
Secretions pass into the gut, resp tract or exterior of the body
How is the endocrine system controlled?
By a feedback mechanism - demand and supply are well balanced
Clinical symptoms due to endocrine disease?
Underproduction/non-functioning e.g. diabetes
Overproduction
Mass
Malignancy
Endocrine system examples?
Hypothalamus
Pit gland
Thyroid gland
What is the hypothalamic-pituitary axis? Features?
Connection between hypothalamus and pit gland (releases hormones) - thyroid/adrenal stimulate hormones
Rich in blood supply as hypothalamus controls the endocrine system
Structure of the adrenal gland?
Outer = cortex: Zona glomerulosa (outer) Zona fasciculata. Zona reticularis. Inner = medulla
Diagnostic tools for the adrenal gland?
24hr urinary cortisol
Serum ACTH levels
Diurnal pattern of serum cortisol levels
Causes of hypocorticalism?
Hypothalamic pituitary disease
Primary adrenal failure: Developmental, haemorrhagic necrosis, autoimmunity, destruction by TB or tumour
Iatrogenic: Suppression due to steroid therapy
Effects of hypocorticalism?
- Skin pigmentation
- Hypotension
- Muscle weakness
- Hypoglycaemia
- Hyponatraemia
- Hyperkalaemia
- Renal dysfunction
Types of hyperccorticalism?
Cushing’s syndrome - adrenal tumours, iatrogenic
Cushings disease - pit microadenomas
Conn’s syndrome - excessive aldosterone
Adreno-genital syndrome
What is Pheochromocytoma?
Tumour of catecholamine producing
chromaffin cells
• Paroxysmal hypertension - pt likely to die so special anaesthetist needed
Associations of Pheochromocytoma?
Familial – autosomal dominant • Neurofibromatosis • Von Hippel-Lindau disease • Medullary carcinoma of thyroid • Parathyroid adenomas
Behaviour of Pheochromocytoma?
Most are benign
• 5 – 10% are malignant
• Metastasise to lymph nodes, lungs, liver
and bone
How can pathology present?
Manifest as thyroid enlargement or increased/decreased amount of thyroid
Thyroid pathology diagnostic tools?
Serum T3, T4, TSH, calcitonin Ultrasound Radioactive iodine uptake studies FNA Core biopsy
Cytology of thryroid pathology?
Can establish diagnosis of some types of carcinoma: papillary, medullary, anaplastic Can’t distinguish between benign and malignant follicular lesions
Thyroid disease classification?
Hypothyroidism:
- Iodine def
- Developmental
- Autoimmune
- Radiotherapy
- Drugs
Hyperthyroidism:
- Autoimmune
- Toxic adenomas
Masses
What is goitre?
Enlarged thyroid
Name the autoimmune thyroid diseases?
Hashimoto thyroiditis
Graves disease
3:34 Hashimoto thyroiditis…
Autoimmune hypothyroidism
Middle aged women
Auto-antibodies against thyroglobulin…
Thyroid mass can present as?
Cyst
Dominant nodule in mutlinodular goitre
Benign neoplasms
Malignant neoplasms
Benign neoplasm
Follicular adenoma
usually solitary and encapsulated
Commoner than malignant neoplasms
