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Hyponatremia
Hyponatremia or hyponatraemia is a low concentration of sodium in the blood. It is generally defined as a sodium concentration of less than 135 mmol/L (135 mEq/L), with severe hyponatremia being below 120 mEq/L. Symptoms can be absent, mild or severe. Mild symptoms include a decreased ability to think, headaches, nausea, and poor balance. Severe symptoms include confusion, seizures, and coma; death can ensue. The causes of hyponatremia are typically classified by a person's body fluid status into low volume, normal volume, or high volume. Low volume hyponatremia can occur from diarrhea, vomiting, diuretics, and sweating. Normal volume hyponatremia is divided into cases with dilute urine and concentrated urine. Cases in which the urine is dilute include adrenal insufficiency, hypothyroidism, and drinking too much water or too much beer. Cases in which the urine is concentrated include syndrome of inappropriate antidiuretic hormone secretion (SIADH). High vo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Syndrome Of Inappropriate Antidiuretic Hormone Secretion
Syndrome of inappropriate antidiuretic hormone secretion (SIADH) is characterized by excessive unsuppressible release of Vasopressin, antidiuretic hormone (ADH) either from the posterior pituitary gland, or an abnormal non-pituitary source. Unsuppressed ADH causes an unrelenting increase in solute-free water being returned by the tubules of the kidney to the venous circulatory system, circulation. The causes of SIADH are grouped into six categories: 1) central nervous system diseases that directly stimulate the hypothalamus, the site of control of ADH secretion; 2) various cancers that synthesize and secrete ectopia (medicine), ectopic ADH; 3) various lung diseases; 4) numerous drugs that chemically stimulate the hypothalamus; 5) inherited mutations; and 6) miscellaneous largely transient conditions. ADH is derived from a preprohormone precursor that is synthesized in cells in the hypothalamus and stored in vesicles in the posterior pituitary. ''Appropriate'' ADH secretion is r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |