diabetes mellitus
a disorder of carbohydrate metabolism characterized by the impaired ability of the body to produce or respond to insulin and thereby maintain proper levels of sugar (glucose) in the blood.
Causes and types
Insulin is a hormone secreted by beta cells, which are located within clusters of cells in the pancreas called the islets of Langerhans. Insulin's role in the body is to trigger cells to take up the carbohydrate glucose so that the cells can use this energy-yielding sugar. Persons with diabetes are impaired in the ability to metabolize glucose, and as a result the levels of glucose in the blood increase (a condition called hyperglycemia, or high blood sugar). As glucose accumulates in the blood, excess levels of this sugar are excreted in the urine. Because of greater amounts of glucose in the urine, more water is excreted with it, causing an increase in urinary volume and frequency of urination as well as thirst. (The name diabetes mellitus refers to these symptoms: diabetes, from the Greek diabainein, meaning “to pass through,” describes the copious urination, and mellitus, from the Latin meaning “sweetened with honey,” refers to sugar in the urine.) Other symptoms of diabetes include itching, hunger, weight loss, and weakness.
There are two major forms of the disease.
Type I, insulin-dependent diabetes mellitus (IDDM), formerly referred to as juvenile-onset diabetes, usually arises in childhood. IDDM is an autoimmune disorder in which the diabetic person's immune system produces antibodies that destroy the insulin-producing beta cells. Because the body is no longer able to produce insulin, daily injections of the hormone are required.
Type II, non-insulin-dependent diabetes mellitus (NIDDM), which was once called adult-onset diabetes, usually occurs after 40 years of age and becomes more common with increasing age. NIDDM arises from either sluggish pancreatic secretion of insulin or reduced responsiveness in target cells of the body to secreted insulin; sometimes both factors are involved. It is linked to genetics and obesity, notably upper-body obesity. People with NIDDM can control blood glucose levels through diet and exercise and, if necessary, by taking insulin injections or oral medications.
Despite their former classifications as juvenile or adult, either type of diabetes can occur at any age. NIDDM is by far the most common type of diabetes, accounting for about 90 percent of all cases.
Diabetes mellitus also may develop as a secondary condition linked to another disease, such as pancreatic disease; a genetic syndrome, such as myotonic dystrophy; or drugs, such as glucocorticoids.
Gestational diabetes is an ephemeral condition associated with pregnancy. In this situation, blood glucose levels increase during pregnancy but usually return to normal after delivery. However, gestational diabetes is recognized as a risk for developing type II diabetes later in life.
Diagnosis and treatment
Many people are unaware that they have diabetes. In the late 20th century, for example, it was estimated that more than 5 million of the 15.7 million American cases were undiagnosed. The disease is usually discovered when there are typical symptoms and a clearly high blood sugar level, as defined by a daytime level greater than 200 milligrams per decilitre or a fasting level greater than 140 milligrams per decilitre. Occasionally a more detailed oral glucose tolerance test is required for accurate diagnosis.
Before the isolation of insulin in the 1920s, most patients died within a short time after onset.
Untreated diabetes leads to ketoacidosis, the accumulation of ketones (products of fat breakdown) and acid in the blood. Continued buildup of the toxic products of disordered carbohydrate and fat metabolism result in nausea and vomiting, and eventually the patient goes into a diabetic coma.
Treatment aimed at controlling diabetes is highly successful.
All patients are put on restrictive diets designed to help them reach and maintain normal body weight and to limit their intake of sugars and fats.
Frequently they are encouraged to exercise regularly, which enhances the movement of glucose into muscle cells and blunts the rise in blood glucose that follows carbohydrate ingestion.
Diabetics who are unable to produce insulin in their bodies receive regular injections of the hormone, often customized according to their individual and variable requirements. In addition to conventional beef-pork insulin—which is the pancreatic extract of pigs and cattle—human insulin, based on recombinant deoxyribonucleic acid (DNA) technology, became available foruse in the 1980s.
Research into other areas of insulin delivery include pancreas transplantation and implantable mechanical insulin infusion systems. Medications in the form of oral hypoglycemic (blood-sugar-lowering) agents are also available.
The objective of all forms of treatment of diabetes is to keep the level of blood sugar within normal limits and thus reduce the complications, primarily cardiovascular, that account for most diabetes-related deaths. Other serious complications include a condition known as diabetic retinopathy (retinal changes that can lead to blindness), kidney disease, and frequent infection.
diabetes insipidus
pathological endocrine condition characterized by extreme thirst and excessive production of very dilute urine. The essential feature of the disorder appears to be a lack of antidiuretic hormone (vasopressin) or a blocking of its action. This hormone, produced by the hypothalamus, regulates the kidney's conservation of waterand production of urine.
The causes may be numerous: failure of osmoreceptors; tumours;inflammation of the hypothalamusor posterior pituitary lobe (neurohypophysis) by such diseases as syphilis or meningitis; granulomas; trauma, such as skull fracture or concussion; lesions; or failure of the tubules to respond to antidiuretic hormone.
The form of the disorder that results from injury to the hypothalamic nucleus, which is the tract by which vasopressin is conveyed to the neurohypophysis for storage, is called supraoptic hypophyseal diabetes insipidus, or SHDI. Nephrogenic diabetes insipidus (NDI) results when the supplies of vasopressin are adequate but the kidney tubules are unresponsive—either genetically or because of potassium depletion, high levels of serum calcium, or other disorders. SHDI can be alleviated by injections of vasopressin-like compounds of animal or synthetic origin; such treatment, however, is ineffective for NDI.
요붕증(尿崩症)
♥ [정 의]
- 뇌하수체 후엽의 기능저하에 의해 일어나는 수분 대사 장해. 뇌하수체 후엽에서 분비되는 항이뇨호르몬의 분비가 저하되어 뇨가 농축되지 못한 채 체내의 수분이 자꾸 소변으로 배설되는 질병임
♥ [관련신체부위]
- 뇌하수체, 내분비계
♥ [성별/나이]
-남녀 모든 연령층에서 발생
♥ [증 상]
- 아무리 마셔도 갈증해소가 어려움
- 소변량이 많고(하루에 7리터이상), 묽고, 색이 없음
- 손에 건조감
- 변비
♥ [원인]
- 뇌하수체 후엽에서 분비되는 항이뇨 호르몬이 부족되어 생기는 질환이며 다음의 원인에 의함
두부 외상에 의해 뇌하수체가 손상을 입음
뇌하수체의 종양
뇌의 다른 부위에 종양이 생겨 뇌하수체가 압박을 받은 경우
뇌염, 뇌수막염 등 뇌의 감염
두개골내의 출혈
신장질환
동맥류(동맥벽의 한 부분이 혹처럼 튀어나옴 ; 곧 터질 상태)
♥ [위험인자]
- 뇌의 질병, 외상
- 동맥경화증
- 뇨붕증의 가족력이 있을 경우
♥ [합병증]
나트륨, 칼륨 결핍과 같은 전해질 불균형이 일어나며 이로 인해 불규칙적인 심박동, 피로, 울혈성 심부전증이 일어날 수 있음
♥ [치료전망]
- 뇨붕증이 종양이나 동맥류에 의해 일어났을 경우에는 수술로 치료가능
- 두부 손상에 의한 경우는 1년 이내에 자연치유됨
- 뇌 감염에 의해 생긴 경우는 증상 치료 불가능
♥ [치료법]
1. 일반요법
뇌수술이 필요한 경우 수술함
2. 약물요법
합성 항이뇨호르몬(vasopressin,desmopressin acetate)을 투여함
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