ENDOCRINE & METABOLIC DISORDERS II

1. ENDOCRINE & METABOLIC DISORDERSII

2. ENDOCRINE PATHOLOGY

3. PARATHROIDGLANDS

5. Primary hyperparathyroidism Etiology: • Parathyroid adenoma (80%) • Parathyroid hyperplasia (15%) • Parathyroid carcinoma is very rare • Para-neoplastic syndrome: lungs and renal carcinomas can secrete parathyroid-like substances and give a picture of hyperparathyroidism

6. Pathogenesis: • Excess production of parathyroid hormone (PTH) leads to hypercalcaemia Clinically: • Laboratory: elevated serum calcium and PTH • Kidney stones • Osteoporosis (calcium moves out of Bones) • Metastatic calcification (abnormal deposition of calcium in tissues) • Neurological changes

7. Secondary Hyperparathyroidism Etiology: • Chronic renal failure • Vitamin D deficiency • Malabsorption Pathogenesis: -Caused by any disease that results in hypocalcaemia, leading to increased secretion of PTH by the parathyroid glands

8. Hypo-parathyroidism Etiology: • Surgical removal of gland during thyroidectomy • Digeorge syndrome (congenital absence of parathyroid glands)

9. Clinical picture of hypoparathyroidism 1-Lab: hypocalcaemia 2-Neuromuscular excitability and tetany: -Trousseau sign of latent tetany (eliciting carpal spasm by inflating the blood pressure cuff and maintaining the cuff pressure above systolic) -Chvostek's sign (tapping of the inferior portion of the zygoma will produce facial spasms) 3-Psychiatric disturbances 4-Cardiac conduction defects

10. PITUITARY GLAND Normal pituitary gland

11. Gigantism: Children & adolescents Before fusion of growth plates Tall stature & long extremities Acromegaly: Adults After fusion Prominent jaw Flat, broad forehead Enlarged hands and feet Visceral abnormalties Growth hormone producing adenoma • Elevated growth hormone

12. Gigantism

13. Acromegaly

14. Pituitary Dwarfism Definition • Dwarfism is a condition in which the growth of the individual is very slow or delayed, resulting in less than normal adult stature.

15. Pituitary Dwarfism

16. Therefore, pituitary dwarfism is decreased bodily growth due primarily to hormonal problems (decreased growth hormone). • The end result is a proportionate little person, because the height and the growth of all other structures of the individual are decreased.

17. ADRENAL GLAND

18. Adrenal hyperfunction diseases

19. Cushing syndrome • Definition: Disease characterized by increased levels of glucocorticoids Causes of Cushing’s Syndrome: • Adenoma of adrenal cortex • Excessive secretion of adreno-corticotrophic hormone (ACTH) • Prolonged administration of glucocorticoids

20. Clinical features of Cushing disease: • Trunkal obesity • Hypertension • Glucosuria • Menstrual and sexual dysfunction • Hirsutism and acne • Muscle weakness • Osteoporosis • Poor wound healing • Edema • More susceptible to infections

21. Clinical features of Cushing’s disease

22. Adrenal gland insufficency

23. Addison’s disease(chronic adrenocortical insufficiency) • Definition: • Destruction of the adrenal cortex, leading to a deficiency of glucocorticoids and androgens • Etiology: • Autoimmune adrenalitis • Tuberculosis • Metastatic cancer

24. Clinical presentation: • Gradual onset of weakness • Skin pigmentation • Hypotension • Hypoglycemia • Poor response to stress

25. Addison’s disease

26. METABOLIC DISORDERS

27. CALCIUM METABOLIC DISORDERS

28. CALCIUM METABOLISM • Definition: • Calcium metabolism is the mechanism by which the body maintains adequate calcium levels.

29. Sources of calcium: Calcium enters the body in a normal diet. Vitamin D is an important co-factor in the intestinal absorption of calcium.

30. Calcium location in the body: • 99% in the skeleton in the form of calcium phosphate salts. • The extracellular fluid (ECF) and the serum.

31. DISORDERS OF CALCIUM METABOLISM

32. Calcium • Regulated by three hormones • Parathyroid hormone (PTH) • Increases plasma calcium levels • Vitamin D • Fat-soluble steroid; increases calcium absorption from the gatrointectinal tract • Calcitonin • Decreases plasma calcium levels

33. HYPERCALCAEMIA Definition: Hypercalcaemia is an elevated calcium level in the blood. It can be due to 1-excessive skeletal calcium release, 2-increased intestinal calcium absorption, or 3-decreased renal calcium excretion

34. Causes of hypercalcaemia • Hyperparathyroidism and malignancy account for ~90% of cases • Vitamin D metabolic disorders • Renal failure

35. Signs and symptoms: • Hypercalcaemia can result in fatigue, depression, confusion, anorexia, nausea, vomiting, constipation, pancreatitis, renal stones and bladder stones. • Abnormal heart rhythms. • Severe hypercalcaemia is considered a medical emergency: at these levels as coma and cardiac arrest can result.

36. Hypocalcaemia Definition: Hypocalcaemia is the presence of low serum calcium levels in the blood.

37. Cause: • Eating disorders • Magnesium over supplementation • Prolonged use of medications/laxatives containing magnesium • Absent parathyroid hormone • Absent active vitamin D • Decreased sun exposure • Intestinal malabsorption

38. Symptoms: • Peri-oral tingling and decreased sensations. • Tetany, carpo-pedal spasm are seen. • Latent tetany • Trousseau sign of latent tetany (eliciting carpal spasm by inflating the blood pressure cuff and maintaining the cuff pressure above systolic) • Chvostek's sign (tapping of the inferior portion of the zygoma will produce facial spasms) • Tendon reflexes are hyperactive

39. Life threatening complications: Laryngospasm Cardiac arrhythmias

40. Hypocalcemia Increased neuromuscular excitability Muscle cramps Hypercalcemia Decreased neuromuscular excitability Muscle weakness Increased bone fractures Kidney stones Constipation Hypocalcemia and Hypercalcemia

41. Vitamin D deficiency: SIGNS OF VITAMIN D DEFICIENCY: • Rickets (children) • Osteomalacia (adults) • Vitamin D excess: → hypercalcaemia and kidney stones.

42. Rickets • A disease that is characterized by deficient mineralization of bone in children (before epiphyseal closure) leading to softening of the bones and potentially leading to fractures and deformity. • It is caused by Vitamin D deficiency which leads to decreased absorption of calcium

43. Vit. D deficiency may be due to: 1-Malnutrition associated with decreased exposure to sunlight 2-Secondary to intestinal malabsorption

44. Pathological features • There is abnormal bony trabeculae with big amounts of uncalcified osteoid leading to soft weak bones

45. Rickets : • Signs and symptoms of rickets include: • Bone pain or tenderness • dental problems (delayed teeth erruption) • muscle weakness (rickety myopathy or "floppy baby syndrome") • increased tendency for fractures (easily broken bones), especially greenstick fractures • Skeletal deformity: Bowed legs, cranial, spinal and pelvic deformities • Growth disturbances • Thoracic changes – pigeon breast deformity, ricketic rosary. • Head – cranio-tabes and frontal bossing. • Vertebrae – lumbar lordosis.

47. Diagnosis: • Blood tests: Serum calcium may show low levels of calcium and serum alkaline phosphatase may be high. • X-rays of affected bones may show loss of calcium from bones or changes in the shape or structure of the bones. • Bone biopsy is rarely performed but will confirm rickets.

48. OSTEOMALACIA Osteomalacia is the term used to describe a similar condition occurring in adults, generally due to a deficiency of vitamin D. It is characterized by inadequate mineralization of newly formed bone matrix.

49. Osteomalacia

50. DIABETES MELLITUS