Feline endocrinology

Section 1. Hypothalamus and pituitary

1. Pituitary anatomy and physiology

Pituitary anatomy

Pituitary physiology

Hormones of the adenohypophysis (AL)

Hormones of the neurohypophysis

2. GH excess: acromegaly (hypersomatotropism)

Background and history

Incidence and pathogenesis

Pituitary pathology

Consequences of pituitary pathology

Clinical features and diagnosis

Treatment

Prognosis

3. Other pituitary tumors

Pituitary masses: hyperplasia, adenoma or carcinoma?

Incidence and cell origins of pituitary tumors

Effect of pituitary tumors on target organs and

the direct effects of large tumors

Functional consequences of autonomous hormone production

4. Pituitary surgery

Introduction and general observations

Surgical anatomy

Imaging of the feline pituitary gland

Pituitary adenomas

Transsphenoidal hypophysectomy

Postoperative care

Complications after pituitary surgery

Prognosis

5. Pituitary irradiation

Introduction

Clinical presentation

Advanced imaging

Role of radiation therapy

Modalities of radiation therapy

Nonfunctioning tumors

Growth hormone-secreting pituitary tumors and acromegaly

Adrenocorticotropic hormone-secreting pituitary tumors and feline Cushing’s disease

Radiation-related adverse effects

6. Pituitary GH deficiency and pituitary dwarfism

Introduction

Etiopathogenesis

Clinical features

Differential diagnosis for failure to grow

Diagnosis

Treatment

7. Polyuria, polydipsia and diabetes insipidus

Introduction

Water requirements in healthy cats

Urine concentrating ability in healthy cats

Mechanisms of water retention

Causes of polyuria and polydipsia in cats

The diagnostic approach to polyuria and polydipsia

Treatment of central diabetes insipidus

Prognosis

Section 2. Thyroid gland

8. Thyroid anatomy and physiology

Anatomy of the feline thyroid gland

General thyroid physiology

Serum protein binding of thyroid hormones

Hypothalamic-pituitary-thyroid axis

Extrathyroidal metabolism of thyroid hormone

Thyroid hormone kinetics in the cat

Action of thyroid hormone

9. Hyperthyroidism: background, etiopathogenesis and changing prevalence of feline thyroid disease

History of thyroid disease in cats

Studies into the etiopathology of feline hyperthyroidism

Epidemiology of hyperthyroidism: a common worldwide disorder of senior to geriatric cats

Why has feline nodular goiter reached such epidemic proportions?

Conclusions

10. Hyperthyroidism: clinical signs and physical examination findings

Signalment

Clinical signs

Physical examination

11. Hyperthyroidism: laboratory diagnosis

Clinicopathologic abnormalities associated with hyperthyroidism

Thyroid hormone abnormalities associated with hyperthyroidism

Other diagnostic tests

Conclusion

12. Thyroid and kidney disease in cats

Hyperthyroidism and chronic kidney disease (CKD)

Effect of hyperthyroidism on serum test results of renal function

Effect of hyperthyroidism on urinary markers of renal function

Effect of hyperthyroidism on systolic blood pressure

Effect of treatment of hyperthyroidism on renal function

Effect of azotemia on how hyperthyroid cats are managed

Suggested management strategies for hyperthyroid cats with CKD

13. Thyroid imaging

Introduction

Thyroid embryology, radiographic anatomy, and ectopic thyroid tissue

Normal thyroid

Hyperthyroidism

Ectopic thyroid

Thyroid carcinoma

Thyroid cysts

Hypothyroidism

14. Treatment of hyperthyroidism: antithyroid drugs

Considerations prior to initiating therapy with antithyroid drugs

Mechanism of action of antithyroid drugs

Formulations of antithyroid drugs

Dosages of antithyroid drugs

Adverse reactions with antithyroid drugs

Monitoring cats treated with antithyroid drugs

Other drugs of interest in managing hyperthyroid cats

Success rate and survival in hyperthyroid cats managed with an antithyroid drug

Renal function and hyperthyroidism

Conclusion

15. Treatment of hyperthyroidism: surgical thyroidectomy

Introduction and overview

Anatomy of the thyroid gland and surrounding structures

Preoperative evaluation

General anesthesia

Feline thyroidectomy techniques

Perioperative complications

Postoperative recurrence of hyperthyroidism

Surgical excision of thyroid adenocarcinoma

Summary and conclusions

16. Treatment of hyperthyroidism: radioiodine

Introduction

Advantages and disadvantages of radioiodine treatment of hyperthyroidism

Principles of radioiodine treatment

Specific indications for radioiodine treatment

Patient selection and preparation before radioiodine treatment

Thyroid scintigraphy for evaluation of hyperthyroid cats before 131I treatment

Estimation of the radioiodine dose to administer to cats with hyperthyroidism

Adverse effects or complications associated with radioiodine treatment

Follow-up thyroid function testing after radioiodine treatment

Prognosis after radioiodine treatment

17. Treatment of hyperthyroidism: diet

General nutritional assessment for the hyperthyroid cat

Weight loss and muscle wasting

Nutrients needed for the hyperthyroid cat

Nutritional management of feline hyperthyroidism: feeding a low-iodine diet

18. Treatment of hyperthyroidism: severe, unresponsive, or recurrent hyperthyroidism

Introduction

Etiology and pathogenesis of severe, unresponsive or recurrent hyperthyroidism

Correlation between the severity and duration of hyperthyroidism and the severity of clinical signs

Causes for treatment failure

Therapy for severe, unresponsive hyperthyroidism

Summary

19. Hypothyroidism

Introduction

Causes of hypothyroidism

Clinical subtypes of hypothyroidism

Refractory hypothyroidism

Section 3. Calcium and parathyroid glands

20. Hypercalcemia

Overview

Calcium physiology

Laboratory testing

Initial investigation in hypercalcemic cats

Differential diagnosis of hypercalcemia

21. Feline primary hypoparathyroidism

and hypocalcemia

Introduction

Distribution of calcium in the body

Control of calcium (Ca) homeostasis

Hypocalcemia in people and dogs

Hypoparathyroidism in cats

Differential diagnosis of hypocalcemia

Diagnostic testing

Treatment

Section 4. Adrenal glands

22. Adrenal anatomy and physiology

Adrenal anatomy

Adrenal physiology

23. Cushing’s syndrome (hypercortisolism)

Introduction

Etiology

Clinical features

Clinicopathological findings

Endocrine testing

Diagnostic imaging

Treatment

Prognosis

24. Primary hyperaldosteronism (Conn’s syndrome)

Introduction

Primary hyperaldosteronism

25. Other adrenal cortical tumors and pheochromocytoma

Introduction and differential diagnosis

Working up a feline adrenal mass

Excessive progesterone production

Combined excesses in progesterone and aldosterone

Excessive androgen or estradiol production

Pheochromocytoma

Non-functional adrenal tumors

26. Adrenal surgery via open and laparoscopic approaches

Introduction

Diagnostic evaluation

Case selection

Patient preparation

Surgical techniques

Post-operative care

Complications

27. Feline hypoadrenocorticism

Introduction

Prevalence

Causes

Age, breed and gender

Clinical signs

Clinical pathology

Diagnostic imaging

Electrocardiography and echocardiography

Endocrine tests

Differential diagnoses

Treatment

Prognosis

28. Glucocorticoid therapy

Physiology

Pharmacology

Therapeutic applications

Adverse effects

Glucocorticoid reduction protocol

Section 5. Endocrine pancreas

29. Anatomy, histology and physiology of the feline endocrine pancreas

Anatomy of the feline pancreas

Cell types

Cross-differentiation

General function of islet hormones

Secretory control

Relative importance of pancreatic hormones and their contribution to the pathophysiology of diabetes mellitus

Pancreatic amyloid as the most typical

histological finding in diabetes mellitus

30. Pathogenesis and clinical observations of uncomplicated diabetes mellitus

Introduction

Prevalence and epidemiology

Risk factors

Pathophysiologic mechanisms

Diabetes mellitus and pancreatitis

Clinical and laboratory findings

Survival and prognostic factors

31. Diabetic ketosis, ketoacidosis, and the hyperosmolar syndrome

Introduction

Glucose homeostasis

Clinical presentation of DKA and HHSr

Principles of management of DKA and HHS

Fluid and electrolyte therapy

Insulin therapy

Additional supportive therapy in DKA and HHS

Prognosis of DKA and HHS in cats

32. Insulin treatment of diabetes mellitus

Aims of the treatment and management plan

Insulin therapy

Choosing an insulin

Frequency of insulin administration, initial

insulin dose and change in the type of insulin

Storage, mixing and dilution of insulin

Owner education

Insulin dosing pens 33. Gastrointestinal hormones and the use of non-insulin therapies for diabetes mellitus

Introduction

Incretin hormones physiology and pharmacology

Metformin

Glipizide

Acarbose

SGLT-2 antagonists

Challenges in managing feline DM and potential

uses of non-insulin therapies

34. Dietary management for diabetes mellitus

Overview

Learning outcomes

Case 1: feeding cats that refuse or dislike their “diabetes diet”

Case 2: an insulin overdosed diabetic cat that has just recovered from a severe “hypo” (neuroglycopenia)

Case 3: non-prescription diet alternatives

Case 4: achieving weight loss in a diabetic cat

Case 5: managing diabetes in a cat with concurrent disease

Case 6: the client has looked up a lot of information about diabetes in cats on the internet

35. Monitoring diabetes in cats

Clinical signs

Blood glucose monitoring

Continuous glucose monitoring systems (CGMS) and flash glucose monitoring systems

Urine glucose measurement

Fructosamine concentration

Glycated hemoglobin

36. Diabetic remission

Definition of diabetic remission

Physiology of diabetic remission

Incidence of diabetic remission

Predictors of diabetic remission

Maximizing the likelihood of diabetic remission

Identification and management of the diabetic cat in remission

Prognosis and diabetic relapse

Conclusions

37. The unstable diabetic

Overview

Initial goals of therapy and factors that influence remission

Classification of diabetes mellitus and relevance to unstable diabetic cats

Inappropriate choice of insulin

Inappropriate dosing

Choice of intensive versus conservative insulin management of newly-diagnosed diabetics

Client factors

Underlying diseases

Rebound hypoglycemia (Somogyi)

The brittle diabetic

Monitoring

Other management strategies

Conclusion

38. Hypoglycemia

Introduction

Pathophysiology of hypoglycemia

Blood glucose measurement

Differential diagnoses

Specific diseases or syndromes associated with hypoglycemia in cats

Diagnostic approach

Treatment of hypoglycemia

Section 6. Blood pressure, body condition and nutrition

39. Feline obesity

Epidemiology

Pathophysiology of obesity

Obesity-related diseases

Treatment

40. Disorders of lipid metabolism

Introduction

The basics of lipoprotein metabolism

Definitions and measurement of feline serum lipid concentrations

Effect of lipemia on the measurement of other analytes

Causes of feline hyperlipidemia

Clinical consequences of hyperlipidemia in cats

Diagnostic approach to cats with hyperlipidemia

Treatment of feline hyperlipidemia

41. Cachexia and sarcopenia

Cachexia

Sarcopenia

Diagnosis of cachexia and sarcopenia

Potential interventions for cachexia and

sarcopenia

Practical approach to treatment of cachexia and sarcopenia in cats

Conclusion

42. Hypertension

Introduction

Measurement of blood pressure in cats

Defining hypertension and deciding when to treat

Consequences of hypertension

Endocrine causes of hypertension

Management of hypertension

43. Conversion tables

Conversion to Systeme International (SI) Units