Endocrine diseaseEndocrine diseases are disorders of the endocrine system. The branch of medicine associated with endocrine disorders is known as endocrinology. Broadly speaking, endocrine disorders may be subdivided into three groups: Endocrine gland hypofunction/hyposecretion (leading to hormone deficiency) Endocrine gland hyperfunction/hypersecretion (leading to hormone excess) Tumours (benign or malignant) of endocrine glands Endocrine disorders are often quite complex, involving a mixed picture of hyposecretion and hypersecretion because of the feedback mechanisms involved in the endocrine system.
Calcium in biologyCalcium ions (Ca2+) contribute to the physiology and biochemistry of organisms' cells. They play an important role in signal transduction pathways, where they act as a second messenger, in neurotransmitter release from neurons, in contraction of all muscle cell types, and in fertilization. Many enzymes require calcium ions as a cofactor, including several of the coagulation factors. Extracellular calcium is also important for maintaining the potential difference across excitable cell membranes, as well as proper bone formation.
Vitamin D deficiencyVitamin D deficiency or hypovitaminosis D is a vitamin D level that is below normal. It most commonly occurs in people when they have inadequate exposure to sunlight, particularly sunlight with adequate ultraviolet B rays (UVB). Vitamin D deficiency can also be caused by inadequate nutritional intake of vitamin D; disorders that limit vitamin D absorption; and disorders that impair the conversion of vitamin D to active metabolites, including certain liver, kidney, and hereditary disorders.
Vitamin DVitamin D is a group of fat-soluble secosteroids responsible for increasing intestinal absorption of calcium, magnesium, and phosphate, and many other biological effects. In humans, the most important compounds in this group are vitamin D3 (cholecalciferol) and vitamin D2 (ergocalciferol). The major natural source of the vitamin is synthesis of cholecalciferol in the lower layers of epidermis of the skin, through a photo-chemical reaction of UVB light, from the sun exposure (specifically UVB radiation) or UVB lamps.
HypermagnesemiaHypermagnesemia is an electrolyte disorder in which there is a high level of magnesium in the blood. Symptoms include weakness, confusion, decreased breathing rate, and decreased reflexes. Complications may include low blood pressure and cardiac arrest. It is typically caused by kidney failure or is treatment-induced such as from antacids that contain magnesium. Less common causes include tumor lysis syndrome, seizures, and prolonged ischemia. Diagnosis is based on a blood level of magnesium greater than 1.
CholecalciferolCholecalciferol, also known as vitamin D3 and colecalciferol, is a type of vitamin D that is made by the skin when exposed to sunlight; it is found in some foods and can be taken as a dietary supplement. Cholecalciferol is made in the skin following UVB light exposure. It is converted in the liver to calcifediol (25-hydroxyvitamin D) which is then converted in the kidney to calcitriol (1,25-dihydroxyvitamin D). One of its actions is to increase calcium uptake by the intestines.
HyperphosphatemiaHyperphosphatemia is an electrolyte disorder in which there is an elevated level of phosphate in the blood. Most people have no symptoms while others develop calcium deposits in the soft tissue. Often there is also low calcium levels which can result in muscle spasms. Causes include kidney failure, pseudohypoparathyroidism, hypoparathyroidism, diabetic ketoacidosis, tumor lysis syndrome, and rhabdomyolysis. Diagnosis is generally based on a blood phosphate levels of greater than 1.46 mmol/L (4.5 mg/dL).
TetanyTetany or tetanic seizure is a medical sign consisting of the involuntary contraction of muscles, which may be caused by disorders that increase the action potential frequency of muscle cells or the nerves that innervate them. Muscle cramps caused by the disease tetanus are not classified as tetany; rather, they are due to a lack of inhibition to the neurons that supply muscles. Tetanic contractions (physiologic tetanus) are a broad range of muscle contraction types, of which tetany is only one.
ErgocalciferolErgocalciferol, also known as vitamin D2 and nonspecifically calciferol, is a type of vitamin D found in food and used as a dietary supplement. As a supplement it is used to prevent and treat vitamin D deficiency. This includes vitamin D deficiency due to poor absorption by the intestines or liver disease. It may also be used for low blood calcium due to hypoparathyroidism. It is used by mouth or injection into a muscle. Excessive doses can result in increased urine production, high blood pressure, kidney stones, kidney failure, weakness, and constipation.
