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Transcript of Pathology of the Endocrine System · Pathology of the Endocrine System ... – Antidiuretic hormone...
4/1/2014
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Pathology of the Endocrine
System
นายแพทย ดร.ณตพล ศุภณัฐเศรษฐกุล ภาควิชาพยาธิวิทยา
คณะแพทยศาสตร มหาวิทยาลัยนเรศวร
4 เมษายน พ.ศ. 2557
Topics
• Introduction • Diseases of the Endocrine glands
– Pituitary gland – Thyroid gland – Parathyroid glands – Endocrine pancreas – Adrenal cortex – Adrenal medulla
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Introduction
• Endocrine = (Gr.) endo + krinein (inside) (to secrete) • Primary function of the endocrine glands is to produce hormone to regulate the functions of other cells or organs
• “Ductless glands” (ตางจาก Exocrine gland) • “Autocrine, Paracrine, Endocrine effects” • “Endocrinologist”
Endocrine Glands
• Pituitary gland • Thyroid gland • Parathyroid glands • Endocrine pancreas (Islets of Langerhans) • Adrenal gland
– Adrenal cortex – Adrenal medulla
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Pituitary Diseases
• Pituitary Gland • Pituitary hyperfunction
– Pituitary adenomas
• Pituitary hypofunction – Pituitary insufficiency
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Pituitary Gland
• Located intracranially at “sella turcica” at base of the cranium
• Anterior pituitary – Posterior pituitary
• Connected to the hypothalamus via a stalk
Pituitary Gland
• Anterior pituitary (Adenohypophysis) : – Growth hormone (GH) – Prolactin (PRL) – Adrenocorticotropic hormone (ACTH) – Gonadotropins (Follicle stimulating hormone (FSH) and Luteinizing hormone (LH)
– Thyroid‐stimulating hormone (TSH)
• Posterior pituitary (Neurohypophysis) : – Oxytocin – Antidiuretic hormone (ADH)
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Pituitary Hyperfunction
• Pituitary adenomas • Prolactinomas (lactotropic adenomas) is most common
• Cause Hyperprolactinemia – Amenorrhea (lack of menstruation) – Galactorrhea (milk secretion unrelated to pregnancy) – Infertility (inhibit normal ovulation)
• Somatotropic adenomas : Growth hormone (GH) – Before closure of the epiphyseal plate : Gigantism – After closure of the epiphyseal plate : Acromegaly
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Gigantism
Pituitary Hypofunction
• Panhypopituitarism (pituitary insufficiency) – General weakness, cold intolerance, weight loss, hypotension, amenorrhea, impotence, dwarfism
• Selective pituitary hypofunction
• Diabetes insipidus – A lack of antidiuretic hormone (ADH) secondary to destructive lesions of the hypothalamus or pituitary stalk or tumors of the posterior pituitary
– Secrete large amounts (5‐6 L/day) of hypotonic urine
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Thyroid Diseases
• Thyroid gland • Hyperthyroidism • Hypothyroidism • Thyroid Neoplasms
Thyroid Gland
• An endocrine gland located in the neck • Two types of cells : Follicular cells and C cells • Follicular cells
– Thyroxine or tetraiodothyronine (T4) – Triiodothyronine (T3)
• C cells – Calcitonin involved in maintenance of calcium homeostasis
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Hyperthyroidism
• Hyperthyroidism or thyrotoxicosis is a hypermetabolic state that results from an excess of free thyroid hormone (T3 and T4) in blood
• Graves’ disease (autoimmune disease) – Antibodies to the TSH receptor on the surface of thyroid follicular cells
– Diffusely enlarged gland with lymphoid follicles – Tachycardia, restlessness, sweating, palpitation, tremor, increased appetite, weight loss
– Exophthalmos (bulging eyes) and pretibial myxedema
http://www.immuneweb.com/images/20/figure20‐04.jpg
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Exophthalmos
http://www.beltina.org/pics/exophthalmos.jpg
Hypothyroidism • Congenital developmental defects
– Thyroid dwarfism – Cretinism (mental retardation)
• Autoimmune Hashimoto’s thyroiditis (most common cause of hypothyroidism)
• Thyroidectomy • Iodine deficiency : nodular goiter • Sleepy, lacks of mental alertness, bradycardia, cold intolerance, constipation, muscle weakness
• Myxedema : increased connective tissue deposition (glycoaminoglycans, hyaluronic acid, and other mucopolyscaccharides)
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http://healthtalk.info/wp‐content/uploads/Fig‐2‐cretinism.jpg http://howshealth.com/wp‐content/uploads/2010/11/cretinism.jpg
Dwarfism
Clinical Features
http://healthtalk.info/wp‐content/uploads/Fig‐3‐myxedema‐thyroid‐hormone‐deficiency‐hypothyroidism.jpg
http://www.checkbook.org/sitemap/health/Graves_Disease/..%5CGraphics%5CGraves_eyes.jpg
Myxedema Graves’ dis.
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Goiter
http://s1.hubimg.com/u/2822516_f520.jpg
Thyroid Neoplasms • Follicular adenoma : most common benign tumor
– Small, well encapsulated with fibrous tissue, composed of thyroid follicles
• Papillary carcinoma : 80% of all malignant thyroid tumors – Four times more common in women than in men – Tends to metastasize to the local lymph nodes
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Diseases of the Parathyroid Glands
• Parathyroid Glands • Hyperparathyroidism • Hypoparathyroidism
Parathyroid Glands
• Usually, 4 glands behind the thyroid
• Secrete parathormone (PTH) in response to a decrease in plasma calcium level
• PTH stimulates the release of calcium from bone and also resorption of calcium from urine in the kidney to elevate calcium concentration in blood
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Hyperparathyroidism
• Primary : parathyroid hyperplasia, neoplasia • Secondary : compensatory mechanism triggered by hypocalcemia caused by chronic renal failure, hypovitaminosis D
• Excess of PTH in the circulation • Hypercalcemia : muscle weakness, cardiac arrhythmia, nephrocalcinosis, urolithiasis
• Bone weakness and prone to fracture
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Hypoparathyroidism
• Most commonly occurs after all 4 glands are totally removed during cancer surgery of the neck
• Hypocalcemia : hypocalcemic tetany (muscular spasm), irregular heart beat, cardiac arrest
Endocrine pancreas
• The endocrine cells are arranged into islets of Langerhans, scattered through the entire organ but are most prominent in the tail of pancreas
• The islets of Langerhans contain several endocrine cell types – Alpha cells (20%) secrete glucagon – Beta cells (70%) secrete insulin – Delta cells (10%) secrete somatostatin or pancreatic polypeptide (PP)
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http://www.gopetsamerica.com/anatomy/illustrations/pancreas.jpg
http://wikis.lib.ncsu.edu/images/8/80/Endoexoc.gif http://embryology.med.unsw.edu.au/histology/endocrine/pan20he.jpg
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Diabetes mellitus (DM)
• (Gr) = diabetes + mellitus (sweet) • diabetes = “Pass through” to denote polyuria (large amount of urine)
• DM caused by – Absolute or relative deficiency of insulin – Target tissue resistance to insulin
• Type 1 DM (5‐10%) children and adolescents • Type 2 DM (90‐95%) overweight adults
Clinical features of DM
• Hyperglycemia • Glycosuria Osmotic diuresis Polyuria • Polydipsia • Polyphagia • Muscle wasting and weight loss • Increase lipolysis ketone body formation ketoacidosis
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Complications of DM • Cardiovascular system
– Atherosclerosis, coronary heart disease, stroke – Artery occlusion : DM foot gangrene
• Kidneys – Glomerulosclerosis, pyelonephritis – Renal ischemia, renal failure
• Eyes – Retinal microaneurysm, hemorrhage – Cataract
• Nervous system – Peripheral neuropathy (sensory and motor deficits)
• Immune system – Prone to infection (immunocompromised)
http://upload.wikimedia.org/wikipedia/commons/thumb/f/f1/Atherosclerosis,_aorta,_gross_pathology_PHIL_846_lores.jpg/230px‐Atherosclerosis,_aorta,_gross_pathology_PHIL_846_lores.jpg
Atherosclerosis
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DM Foot gangrene
http://1.bp.blogspot.com/_8HtJsALJ3Q4/TNK37lr9wLI/AAAAAAAAADc/TvtyKgaDodo/s1600/Diabetic+Nephropathy+photo.JPG
Diabetic nephropathy
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http://whatisdiabetesmellitus.org/wp‐content/uploads/2011/11/Diabetic_Retinopathy_Symptoms.jpg
Adrenal Gland • Attached to the upper pole of each kidney • Adrenal cortex • Adrenal medulla
http://www.georgiahealth.edu/medicine/phy/raineylab/images/webfigure1.jpg
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Diseases of the Adrenal Cortex
• Adrenal Gland • Adrenal Cortex • Adrenocortical Hyperfunction • Adrenocortical Hypofunction
Adrenal Cortex
• Consists of 3 zones • Zona glomerulosa – mineralocorticoids (e.g. aldosterone) • Zona fasciculata – glucocorticoids (e.g. cortisone) • Zona reticularis – sex steroids (e.g. estrogens and androgens)
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http://humanphysiology2011.wikispaces.com/file/view/structure_of_adrenal_glands.jpg/198568168/structure_of_adrenal_glands.jpg
Adrenocortical Hyperfunction
• Hyperaldosteronism (Conn’s syndrome) – Hypersecretion of mineralocorticoids (aldosterone)
• Hypercorticolism (Cushing’s syndrome) – Hypersecretion of glucocorticoids (cortisol) – Most common of these three syndromes
• Adrenogenital syndrome – Hypersecretion of adrenal sex steroids (androgens)
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Cushing’s syndrome
• Excessive production of cortisol caused by – Adrenocortical tumors : adenoma, carcinoma – Exogenous corticosteroids
• Cushing’s disease : hypercortisolism caused by hypersecretion of the ACTH either from – pituitary adenoma or – small‐cell lung cancer (paraneoplastic)
• Clinical features : Central obesity, moon face, buffalo hump, hypertension, thinning of the skin and striae
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Adrenocortical Hypofunction
• Adrenal insufficiency or Addison’s disease
• Caused by autoimmune adrenalitis, infection (tuberculosis, histoplasmosis), metastatic tumors (breast, lung)
• Clinical features: fatigue, weight loss, hypotension, syncope, cannot tolerate stress, metabolic disturbance, personality change
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Disease of the Adrenal Medulla
• Adrenal Medulla – Epinephrine, Norepinephrine in ANS
• Neuroblastoma – malignant tumor in children
• Pheochromocytoma – benign tumor causing secondary hypertension in the young