|
Jaundice, also known as icterus, is a yellowish pigmentation of the skin, the conjunctival membranes over the sclerae (whites of the eyes), and other mucous membranes caused by high blood bilirubin levels. This hyperbilirubinemia subsequently causes increased levels of bilirubin in the extracellular fluid. Concentration of bilirubin in blood plasma is normally below 1.2 mg/dL (<25µmol/L). A concentration higher than approx. 3 mg/dL (>50µmol/L) leads to jaundice. The term jaundice comes from the French word ''jaune'', meaning yellow. Jaundice is often seen in liver disease such as hepatitis or liver cancer. It may also indicate leptospirosis or obstruction of the biliary tract, for example by gallstones or pancreatic cancer, or less commonly be congenital in origin (e.g., biliary atresia). Yellow discoloration of the skin, especially on the palms and the soles, but not of the sclera and mucous membranes (i.e. oral cavity) is due to carotenemia—a harmless condition important to differentiate from jaundice. Other things that can cause similar discoloration are, but not limited to, as a side effect to the use of drug mepacrine or excessive exposure to phenols. == Signs and symptoms == The main symptom of jaundice is a yellowish discoloration of the white area of the eye and the skin. Urine is dark in colour. The conjunctiva of the eye are one of the first tissues to change color as bilirubin levels rise in jaundice. This is sometimes referred to as ''scleral icterus''. However, the sclera themselves are not "icteric" (stained with bile pigment) but rather the conjunctival membranes that overlie them. The yellowing of the "white of the eye" is thus more properly termed ''conjunctival icterus''. The term "icterus" itself is sometimes incorrectly used to refer to jaundice that is noted in the sclera of the eyes, however its more common and more correct meaning is entirely synonymous with jaundice.〔〔(Icterus | Define Icterus at Dictionary.com ). Dictionary.reference.com. Retrieved on 2013-12-23.〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「jaundice」の詳細全文を読む スポンサード リンク
|