Diabetes Insipidus Pathophysiology PDF

Diabetes Insipidus Pathophysiology DR WALID THEIB PHD  Diabetes insipidus is caused by abnormality in the functioning or levels of antidiuretic hormone (ADH), also known of as vasopressin. Manufactured in the hypothalamus and stored in the pituitary gland, ADH help...

Diabetes Insipidus Pathophysiology DR WALID THEIB PHD  Diabetes insipidus is caused by abnormality in the functioning or levels of antidiuretic hormone (ADH), also known of as vasopressin. Manufactured in the hypothalamus and stored in the pituitary gland, ADH helps to regulate the amount of fluid in the body.  The two forms of diabetes insipidus In central (cranial) diabetes insipidus, the production or release of ADH is too low to stop the kidneys from passing dilute urine, which results in an increased loss of water and therefore more thirst. People with nephrogenic diabetes insipidus, however, have adequate amounts of ADH in the body but the kidneys fail to respond it, and again the urine is still not concentrated.  Causes of diabetes insipidus Genetic inheritance of a mutation in the vasopressin gene Brain tumors such as pituitary adenoma Head injury causing damage to the pituitary gland or hypothalamus. Injury may also result after brain surgery. Metabolic causes such as high blood sugar, high blood calcium and low potassium. The use of drugs such as lithium used to treat bipolar disorder  pituitary gland diseases Most pituitary adenomas are known as non- functional adenomas and do not produce excessive amounts of hormones, while others can result in hormone overproduction, causing serious endocrine problems, such as acromegaly - Cushing's syndrome - prolactinoma (prolactin excess).  Acromegaly is a disorder that results from excess growth hormone (GH) after the growth plates have closed. The initial symptom is typically enlargement of the hands and feet.  Cushing's syndrome disorder that occurs when your body makes too much of the hormone cortisol over a long period of time  Hypopituitarism Hypopituitarism is a health condition characterized by the reduced production of hormones from the pituitary gland. The pathophysiology of hypopituitarism usually involves damage to the pituitary gland, which renders it unable to produce one or more hormones in the normal manner.  When the production of one or more pituitary hormones is impaired, the gland targeted by the tropic pituitary hormone will have a reduced secretory action Damage to the pituitary gland due to a tumor may occur either because of: impaired blood flow to the gland compression of the pituitary tissue caused by the tumor growth, or by related inflammation.  Growth hormone (GH) deficiency Fatigue Muscle weakness Changes in body fat composition Lack of ambition Social isolation  Luteinizing hormone (LH) and follicle- stimulating hormone (FSH) deficiency Hot flashes Irregular or no periods Loss of pubic hair An inability to produce milk for breast-feeding  Men may also have symptoms such as: Erectile dysfunction Decreased facial or body hair Mood changes  Parathyroid glands are small glands of the endocrine system that control the amount of calcium in our blood and bones. There are 4 parathyroid glands located behind the thyroid gland in the neck that play a very critical role in many body functions.  Hyperparathyroidism occurs when one (or more) of the parathyroids develops a tumor which makes too much hormone leading to high calcium and other bad symptoms. This tumor must be removed.  hyperparathyroidism (PHPT) is characterized by hypersecretion of parathyroid hormone (PTH) leading to hypercalcemia and relative hypophosphatemia  Symptoms of hyperparathyroidism depression. tiredness. feeling thirsty and peeing a lot. feeling sick and losing your appetite. muscle weakness. constipation  Neuroblastoma (NB) is a type of cancer that forms in certain types of nerve tissue. It most frequently starts from one of the adrenal glands but can also develop in the neck, chest, abdomen, or spine. Symptoms may include bone pain, a lump in the abdomen, neck, or chest  Neuroblastoma most commonly affects children age 5 or younger, though it may rarely occur in older children.  In general, cancer begins with a genetic mutation that allows normal, healthy cells to continue growing without responding to the signals to stop, which normal cells do. Cancer cells grow and multiply out of control  Nerve cells and cells of the medulla (center) of the adrenal gland develop from neuroblasts in the fetus. These neuroblasts usually grow and change into mature nerve cells. Neuroblastomas develop when normal fetal neuroblasts do not become mature nerve cells or adrenal medulla cells. Instead, they continue to grow and divide.  Pheochromocytoma is a rare tumor of adrenal gland tissue. It results in the release of too much epinephrine and norepinephrine, hormones that control heart rate, metabolism, and blood pressure  Pheochromocytoma When a tumor composed of the same cells as a pheochromocytoma develops outside the adrenal gland Pheochromocytoma may occur as a single tumor or as more than one growth The tumors may occur at any age, but they are most common from early to mid-adulthood. In few instances, the condition may also be seen among family members (hereditar  Addison's disease also known as primary adrenal insufficiency, is a rare long-term endocrine disorder characterized by inadequate production of the steroid hormones cortisol and aldosterone by the two outer layers of the cells of the adrenal glands (adrenal cortex), causing adrenal insufficiency  symptoms of Addison's disease generally develop gradually Skin changes – Hyperpigmentation of the skin Gastrointestinal changes – Nausea and vomiting – Weight loss – Abdominal pain Behavioral disorders – Anxiety – Depression – Irritability – Poor concentration Changes in females – Loss or irregularity of menstrual cycle – Loss of body hair  causes injury to the adrenal glands. Infection, including tuberculosis, HIV/AIDS- related infections, and fungal infections. Cancer cells from another part of the body that have invaded the adrenal glands. Bleeding into the adrenal glands. Surgical removal of the adrenal glands  Primary adrenal insufficiency When the cortex is damaged and doesn't produce enough adrenocortical hormones, the condition is called primary adrenal insufficiency. This is most commonly the result of the body attacking itself (autoimmune disease). For unknown reasons,  Secondary adrenal insufficiency The pituitary gland makes a hormone called adrenocorticotropic hormone (ACTH). ACTH in turn stimulates the adrenal cortex to produce its hormones. Benign pituitary tumors, inflammation and prior pituitary surgery are common causes of not producing enough pituitary hormone.  Addisonian crisis If untreated Addison's disease, may develop an addisonian crisis as a result of physical stress, such as an injury, infection or illness. Normally, the adrenal glands produce two to three times the usual amount of cortisol in response to physical stress. With adrenal insufficiency, the inability to increase cortisol production with stress can lead to an addisonian crisis. An addisonian crisis is a life-threatening situation that results in low blood pressure, low blood levels of sugar and high blood levels of potassium. need immediate medical care.  pathophysiology caused by an autoimmune response, which occurs when the body's immune system (which protects it from infection) assaults its own organs and tissues. With Addison's disease, the immune system attacks the outer portion of the adrenal glands (the cortex), where cortisol and aldosterone are made Aldosterone deficiency causes sodium wasting, and cortisol deficiency results in the increased antidiuretic hormone. This causes increased water absorption. Hyperkalemia is secondary to low aldosterone levels, which causes potassium retention  The most common cause of Addison disease is idiopathic autoimmune adrenocortical insufficiency resulting from autoimmune atrophy, fibrosis, and lymphocytic infiltration of the adrenal cortex, usually with sparing of the adrenal medulla. This accounts for more than 80% of reported cases. Idiopathic autoimmune adrenocortical atrophy and tuberculosis (TB) account for nearly 90% of cases of Addison disease