Question

VanMeter: Gould's Pathophysiology for the Health Professions, 5th Edition Chapter 16: Endocrine System Disorders Case Studies Case Study 1 Mrs. A has been taking high doses of glucocorticoids for much of the past 2 years to control severe rheumatoid arthritis. She has now developed hypertension and type 2 diabetes and would like to stop taking the cortisone because of the unwanted changes in her appearance. 1. How does Cushing's syndrome affect the individual? :2. Discuss how hypertension and diabetes have developed and the potential complications of these conditions. 3. Discuss other potential problems that Mrs. A may experience resulting from long term use of glucocorticoids. Case Study2 PM is a 15-year-old young woman who had her menstrual period at age 11. Recently, she has been experiencing double vision, headaches, and amenorrhea. A skull MRI indicatesa pituitary adenoma. Blood tests indicate low estrogen, progesterone, and TSH levels. i.1. Discuss the relationship of the pituitary gland to the optic nerve and its role in controlling sex hormones and thyroxine. 2 2. Explain why this benign tumor must be surgically removed. 3. Explain the effects that you would expect to see in PM caused by the reduced TSH level. How will these be treated after surgery? 4. Explain the manifestations that PM has experienced in terms of the pathophysiology.

Answer 1

CASE STUDY-I

1) How does Cushing’s Syndrom affect the individual?

When rheumatoid arthritis patients take over dose of glucocorticoids over long term, it leads to an increase in mean body weight of 4% to 5%. This is thought to be related to increased appetite and dyspepsia that is relieved with eating. Fat redistribution produces a cushingoid appearance including truncal obesity, a buffalo hump, enhanced supraclavicular fat pads, and moon facies in patients on moderate doses of prednisone for prolonged periods. This is Cushing’ Syndrome which Mrs. A experienced leading to unwanted changes of appearance.

2) Discuss how hypertension and diabetes have developed and the potential complication of these conditions.

Long-term exposure to medium-dose glucocorticoid therapy associates with hypertension in patients with rheumatoid arthritis. Also overstimulation of the mineralocorticoid receptor, resulting in sodium retention in the kidney. This results in volume expansion and a subsequent increase in blood pressure.

Long use of glucocorticoids increase blood glucose (sugar) since these drugs promote glucose production in the liver and reduce the sensitivity of the cells to insulin. Consequently, glucose accumulates in the blood and can cause a rise in blood sugar levels. When it's ongoing, it causes the body to stop responding to insulin the way it should. This is called insulin resistance. Over time, the condition raises the risk for type 2 diabetes. This occurs when the body doesn't make enough insulin or resists its effects.

3) Discuss other potential problem that Mrs. A. may experience resulting from long term use of glucocorticoids.

The long term use of glucocorticoids may lead to Cushing’s syndrome due to adrenal adenoma, hypertension, diabetes, high plasma cortisol, also tumor development in the adrenal gland may be noticed. After curing Cushing’s syndrome further complaints of pain on motion, swelling of fingers, wrist, elbows, knees and foot joints i.e, high rheumatoid factors may be present.

CASE STUDY-II

1) Discuss the relationship of the pituitary gland to the optic nerve and its role in controlling sex hormones & thyroxine.

The pituitary gland sits in a space called the pituitary sell, just behind the eyes. Our eyes sends information through optic nerves that travel to the brain by which we can see. Any large pituitary tumor can push these nerves affecting their ability to send visual information from eyes. Sometime it may affect optic nerve on just one side, or to optic chiasm where both optic nerves from each eye merge together causing visual loss to both eyes. Further if it affects other nerves travelling to the eyes it causes double vision.

The pituitary gland secretes hormones that act on the adrenal glands, thyroid gland, ovaries and testes, which in turn produce other hormones. Through secretion of its hormones, the pituitary gland controls metabolism, growth, sexual maturation, reproduction, blood pressure and many other vital physical functions and processes. The anterior pituitary gland produces the luteinising hormone and follicle stimulating hormone, also known as gonadotrophins and releases them into bloodstream. They act on the ovaries or testes to stimulate sex hormone production, and egg and sperm maturity.

The production and release of thyroid hormones, thyroxine and triiodothyronine, is controlled by a feedback loop system that involves the hypothalamus in the brain and the pituitary and thyroid glands. The hypothalamus secretes thyrotropin-releasing hormone which, in turn, stimulates the pituitary gland to produce thyroid stimulating hormone. This hormone stimulates the production of the thyroid hormones, thyroxine and triiodothyronine, by the thyroid gland.

2) Explain why this benign tumour must be surgically removed.

Pituitary tumors are not serious, in over 99% of patients, this is NOT a cancer; it is benign. Although the tumor is benign, it can cause problems because of its size, causing loss of vision, loss of normal pituitary function (hypopituitarism) and/or headache or because of excessive hormone production by the tumor. So benign tumors better be surgically removed.

3) Explain the effects that you would expect to see in PM caused by the reduced TSH level. How will these be treated after surgery?

A low TSH indicates hypothyroidism (overactive thyroid) due to a problem involving the pituitary gland. In cases of hyperthyroidism, the TSH level will be decreased, because there is too much thyroid hormone in the blood. In such cases Drugs (Methimazole, Propranolol) to decrease thyroid levels may be prescribed by the doctor.

4) Explain the manifestations that PM has experienced in terms of the pathophysiology.

Most pituitary tumours are sporadic, but some arise as a component of genetic syndromes such as pituitary adenoma predisposition syndromes. Pituitary tumors are frequently encountered intracranial neoplasms. They present with a variety of clinical manifestations that include symptoms and signs of excessive hormone secretion by the tumor, signs of hormone deficits by the normal pituitary gland and others related to expansion of the tumor mass and the resulting compression of surrounding structures such as the optic chiasm and cranial nerves. Advances in molecular biology, immunocytochemical staining and imaging, and the introduction of new treatment options have improved understanding of the natural history of these adenomas and their management. Available treatments include surgical, medical and radiation therapy.