The Pathological l Basis of Disease

Transcription

1 Endocrine Diseases The Pathological l Basis of Disease - Graduate Course CMM5001 Qiao Li, MD, PhD Faculty of Medicine University of Ottawa qiaoli@uottawa.ca

2 Outline Endocrine System Adrenal Gland Anatomy & Histology Steroid Hormones Addison s Disease Cushing Syndrome Clinical Case Presentation

3 Endocrine Glands Endocrine glands Pineal Pituitary Thyroid Parathyroid Adrenal Neuroendocrine organ Hypothalamus Exocrine & endocrine Pancreas, gonads, placenta Other Thymus, heart, kidney etc. Pineal gland Hypothalamus Pituitary gland Thyroid gland Parathyroid glands (on dorsal aspect of thyroid gland) Thymus Adrenal glands Pancreas Gonads Ovary (female) Testis (male)

4 Characteristics Origin all glands arise from the epithelium (all three germ layers) Microscopic Structure cords, clumps, hollow follicles l & abundant capillaries i Merocrine Secretion

5 Adrenal Gland Anatomy & Histology Steroid Hormones Addison s Disease Cushing Syndrome Clinical Case Presentations

6 Adrenal Gland (Suprarenal)

7 Adrenal Gland in situ Described as loose flesh for the left gland by Claudius Galen ( ) Depicted in 1552 by Bartholomeaus Eustachius ( ) on copper plate Reproduced d by prints in 1563 The Internet Pathology Laboratory for Medical Education

8 Adrenal Gland Male Abdomen The Internet Pathology Laboratory for Medical Education

9 Adrenal Gland - CT

10 Adrenal Gland - MRI

11 Adrenal Gland Gross The Internet Pathology Laboratory for Medical Education

12 Adrenal Gland Cut Surface The Internet Pathology Laboratory for Medical Education

13 Adrenal Gland Cut Surface

14 Adrenal Gland Cross Section

15 Adrenal Gland Medulla Chromaffin cells Catecholamines - epinephrine - norepinephrine i Ganglion cells

16 Adrenal Medulla Medullary chromaffin cells synthesize epinephrine (80%) & norepinephrine (20%) Effects Vasoconstriction Increased heart rate Increased blood glucose levels Blood diverted to brain, heart, & skeletal muscle Hypersecretion Hyperglycemia, increased metabolic rate, rapid heartbeat & palpitations, ti hypertension, intense nervousness, sweating Hyposecretion Not problematic (adrenal catecholamines not essential to life)

17 Adrenal Gland Anatomy & Histology Steroid Hormones Addison s Disease Cushing Syndrome Clinical Case Presentations

18 Adrenal Cortex Three layers of cortex produce three corticosteroids Zona glomerulosa - mineralocorticoids Zona fasciculata - glucocorticoids Zona reticularis - gonadocorticoids Capsule Zona glomerulosa Hormones secreted Aldosterone Adrenal gland Medulla Cortex Kidney Cortex Zona fasciculata Cortisol and androgens Zona reticularis Medulla Adrenal medulla Epinephrine and norepinephrine Drawing of the histology of the adrenal cortex and a portion of the adrenal medulla Photomicrograph (115x)

19 Adrenal Gland Low Power Medulla Zona fasciculata Capsule Zona reticularis Zona glomerulosa Periadrenal fat The Internet Pathology Laboratory for Medical Education

20 Adrenal Gland Low & High Power HP sinusoid HP-zf HP-zr

21 Adrenal Cortex Steroids Zone Class Representative Physiologic Effects glomerulosa fasiculata reticularis mineralocorticoids aldosterone salt and water homeostasis glucocorticoids cortisol carbohydrate metabolism sex steroids androgens & estrogen minimal effects O CH CH 2 OH O CH 2 OH O O O O O

22 Adrenal Steroidogenesis

23 Glucocorticoids & the Receptor Cortisol (hydrocortisone) the majority of glucocorticoid activity in most mammals 90% of circulating cortisol binds to cortisol binding globulin (CBG), for transportation, also limiting the rate of metabolic clearance & the concentration fluctuation Enter cells by passive diffusion i p300/cbp Histone acetylation TAF II 250 TBP RNA Pol II

24 Effects & Usage of Glucocorticoids Carbohydrate, proteins and fat metabolism gluconeogenesis muscle breakdown lipolysis Anti-inflammatory inflammatory and immunosuppressive i Medical Application: arthritis, dermatitis autoimmune diseases fear phobic

25 Homeostasis Hypothalamus connects nervous with ihendocrine via pituitary i Hypothalamic is controlled by neural connections negative feedback from hormones

26 Control of Cortisol Secretion HPA Axis Hypothalamus CRH Anterior Pituitary ACTH Adrenal Cortex Cortisol Dr. Gary Farr

27 The Stress Short-term stress Stress Prolonged stress Nerve impulses Hypothalamus CRH (corticotropinreleasing hormone) Spinal cord Preganglionic sympathetic fibers Adrenal medulla (secretes amino acid based hormones) ACTH Corticotropic cells of anterior pituitary To target in blood Adrenal cortex (secretes steroid hormones) Catecholamines (epinephrine and norepinephrine) Short-term stress response Heart rate increases Blood pressure increases Bronchioles dilate Liver converts glycogen to glucose and releases glucose to blood Blood flow changes, reducing digestive system activity and urine output Metabolic rate increases Mineralocorticoids Glucocorticoids Long-term stress response Kidneys retain Proteins and fats converted sodium and water to glucose or broken down Blood volume and for energy blood pressure Blood glucose increases rise Immune system supressed

28 Adrenal Cortex Disorders CRH CRH ACTH ACTH Cortisol Cortisol

29 Adrenal Gland Anatomy & Histology Steroid Hormones Addison s Disease Cushing Syndrome Clinical Case Presentations

30 Addison s Disease * General languor and debility * Remarkable feebleness of the heart's action * Peculiar change in the color of the skin Chronic adrenocortical insufficiency progressive destruction of 90%of cortex extreme weakness and fatigue unintentional weight loss loss of appetite darkening of the skin low blood pressure, dizziness or fainting craving for salt nausea, diarrhea, vomiting irritability, depression Thomas Addison 1855

31 Primary Adrenocortical Insufficiency * Primary chronic Hypocortisolism - Autoimmune adrenalitis 60-70% - Infections (TB, AIDS) TB 90% - Metastatic neoplasms - Genetic disorder (Addison ss disease) * Primary acute Hypocortisolism - Stress crisis (chronic AI) - Rapid Steroids withdraw - adrenal hemorrhage ACTH Cortisol CRH

32 Secondary Adrenocortical Insufficiency Secondary Hypocortisolism CRH - Hypothalamic pituitary disease - Hypothalamic pituitary suppression ACTH Cortisol

33 Managements Glucocorticoid replacement Mineralocorticoid replacement Prevent adrenal crisis Medic Alert bracelet ACTH CRH Cortisol

34 Prognosis For people with Addison s Disease * prior to 1930, 90% died d within 5 years * from 1930, much better prognosis * since 1950, normal life span

35 Adrenal Atrophy The Internet Pathology Laboratory for Medical Education

36 Adrenal Gland Anatomy & Histology Steroid Hormones Addison s Disease Cushing Syndrome Clinical Case Presentations

37 Causes of Cushing Syndrome

38 Cushing s Disease Excessive Endogenous Cortisol - ACTH dependent: * Pituitary adenoma (70-80%) * Small cell carcinoma - ACTH independent * Cortical tumor Administration of Glucocorticoids - The most common cause CRH ACTH Cortisol Cushing s Disease

39 Ectopic ACTH Secretion Excessive Endogenous Cortisol - ACTH dependent: * Pituitary adenoma * Small cell carcinoma (10%) - ACTH independent * Cortical tumor Administration of Glucocorticoids - The most common cause ACTH Cortisol CRH

40 Adrenal Defects Excessive Endogenous Cortisol - ACTH dependent: * Pituitary adenoma * Small cell carcinoma - ACTH independent * Cortical tumor (10-20%) Administration of Glucocorticoids - The most common cause ACTH Cortisol CRH

41 Exogenous CS Excessive Endogenous Cortisol - ACTH dependent: * Pituitary adenoma * Small cell carcinoma ACTH - ACTH independent * Cortical tumor Administration of Glucocorticoids - The most common cause Cortisol CRH

42 Cushing Syndrome Excessive Endogenous Cortisol - ACTH dependent: * Pituitary adenoma (Cushing s Disease) * Small cell carcinoma - ACTH independent * Cortical tumor Administration of Glucocorticoids - The most common cause ACTH Cortisol CRH Harvey Cushing 1912

43 Adrenal Gland Gr / CS Nodular Cortical Hyperplasia Confluent Nodules

44 Adrenal Gland Low Power Nodular Cortical Hyperplasia Nodule

45 Adrenal Gland High Power Nodular Cortical Hyperplasia

46 Adrenal Gland, cortical adenoma in Cushing Syndrome Gr / CS

47 Adrenal Gland, cortical adenoma - LP

48 Adrenal Gland - Tumor CT

49 Adrenal Gland - Mass MRI : in-phase sequence

50 Adrenal Gland - Adenoma MRI : out-of-phase sequence

51 Clinical Manifestations Moodiness, depression 75-80% Moon face 85% Facial plethora 75% Osteoprosis 75% Truncal obesity (buffalo hump) 85-90% Skin striae (abdomen) 50% Menstrual abnormalities 70% Weakness and fatigability 85% Hirsutism i 75% Hypertension 75% Glucose intolerance / diabetes 70 / 20%

52 Screening Tests 24-hour urine free cortisol level am & pm cortisol level * circadian rhythm, a hall mark

53 DST (Dex Suppression Test) Low-dose Dex suppression * identify Cushing Syndrome CRH High-dose Dex suppression * identify Cushing s Disease ACTH Cortisol

54 Low Dose DST Low-dose DST Day 1: 1 mg of Dex at 11 pm Day 2: blood cortisol at 8 am 0.5 mg of Dex every 6 hrs for 48 hrs 24-hr urinary cortisol for 3 days * identify Cushing Syndrome High-dose DST Day 1: a baseline cortisol at am 8 mg of Dex at t11 pm Day 2: blood cortisol at 8 am 2 mg of Dex every 6 hrs for 48 hrs. 24-hr urinary cortisol for 3 days * identify Cushing's Disease ACTH Cortisol CRH

55 High Dose DST Low-dose DST Day 1: 1 mg of Dex at 11 pm Day 2: blood cortisol at 8 am 0.5 mg of Dex every 6 hrs for 48 hrs 24-hr urinary cortisol for 3 days * identify Cushing Syndrome High-dose DST Day 1: a baseline cortisol at am 8 mg of Dex at t11 pm Day 2: blood cortisol at 8 am 2 mg of Dex every 6 hrs for 48 hrs. 24-hr urinary cortisol for 3 days * identify Cushing's Disease ACTH Cortisol CRH

56 Determining the Etiology Is ACTH dependent? If ACTH dependent * pituitary or ectopic Source of overproduction * MRI pituitary * CT adrenals, chest, abdomen ACTH CRH Cortisol

57 Adrenal Gland - Comparison The Internet Pathology Laboratory for Medical Education

58 Managements Surgical Treatment laparoscopic adrenalectomy CRH Medical Treatment adrenal enzyme blockers ACTH Cortisol

59 Adrenal Gland Anatomy & Histology Steroid Hormones Addison s Disease Cushing Syndrome Clinical Case Presentations

60 Resources Pathologic Basis of Disease Robbins & Ct Cotran 7 th Edition Basic Pathology Robins 7 th Edition Handbook of Clinical Pathology 2 nd nd Edition