The word "jaundice" proceeds from t...

The word "jaundice" proceeds from the French word jaune, which means golden Jaundice is a yellowish staining of the skin, sclera, and mucous membranes at bilirubin, a yellow-orange bile pigment. Bilirubin is formed by means of a breakdown product of heme rings, usually from metabolized r posterity cells. The discoloration typically is find outed clinically once the serum bilirubin of the same height rises above 3 mg by dL (51.3 [micro]mol per L)

Jaundice is not a for the use of all presenting complaint in adults. When ready it may indicate a serious vexed question This article discusses the evaluation of the adult patient with jaundice. A systematic approach is warranted to clarify the cause quickly to such a degree that treatment can begin as promptly as possible.

Pathophysiology

The classic definition of jaundice is a serum bilirubin even greater than 2.5 to 3 mg by means of dL (42.8 to 51.3 [micro]mol by L) in conjunction with a clinical picture of golden skin and sclera. Bilirubin metabolism takes place in three phases--prehepatic, intrahepatic, and posthepatic. Dysfunction in any of these phases may lead to jaundice.

PREHEPATIC PHASE

The human material substance produces about 4 mg by kg of bilirubin per day from the metabolism of heme. Approximately 80 percent of the heme moiety be deriveds from catabolism of red family cells, with the remaining 20 percent resulting from ineffective erythropoiesis and breakdown of muscle myoglobin and cytochromes. Bilirubin is transported from the plasma to the liver for conjugation and excretion. (1)

INTRAHEPATIC PHASE

Unconjugated bilirubin is insoluble in water if it be not that soluble in fats. Therefore, it can easily cros the blood-brain barrier or penetrate the placenta. In the hepatocyte, the unconjugated bilirubin is conjugated with a sugar via the enzyme glucuronosyltransferase and is then soluble in the aqueous bile.

POSTHEPATIC PHASE

formerly soluble in bile, bilirubin is transported by means of the biliary and cystic pipes to enter the gallbladder, where it is stored, or it passes between the sides of Vater's ampulla to enter the duodenum Inside the intestines, a bilirubin is excreted in the stool, while the quiet is metabolized by the intestine flora into urobilinogens and then reabsorbed. The majority of the urobilinogens are filtered from the relations by the kidney and excret in the urine. A small percentage of the urobilinogens are reabsorbed in the intestines and re-excret into the bile.

Clinical Presentation of Jaundice

Patients with jaundice may current with no symptoms at all (i.e., the condition is establish accidentally), or they may not away with a life-threatening condition. The wide range of possibilities is based forward the variety of underlying causes and whether disease attack is quick or slow moving.

Patients presenting with acute illness, which is as a common thing [i]or[/i] matter caused by infection, may pursue medical care because of febrile affection chills, abdominal pain, and flu-like symptoms. For these patients, the change in skin color may not be their greatest concern

Patients with noninfectious jaundice may complain of weight los or pruritus. Abdominal pain is the greatest in quantity common presenting symptom in patients with pancreatic or biliary tract cancers. (2) calm something as nonspecific as depression may be a presenting complaint in patients with chronic infectious hepatitis and in those with a history of alcoholism. (34)

Occasionally, patients may not past nor future with jaundice and some extrahepatic manifestations of liver disease. Examples include patients with chronic hepatitis and pyoderma gangrenosum, and patients with acute hepatitis B or C and polyarthralgias. (5-7)

Differential Diagnosis

Jaundice can be caused on a malfunction in any of the three phases of bilirubin production (Tables 1 and 2) (8) Pseudojaundice can be found with excessive ingestion of provenders rich in beta-carotene (e.g., squash, melon and carrots). Unlike actual jaundice, carotenemia does not originate in scleral icterus or elevation of the bilirubin of the same height (8)

PREHEPATIC CAUSES

Unconjugated hyperbilirubinemia issues from a derailment of the necessary bilirubin conjugation in the hepatocyte. This riddle may occur before bilirubin has jot downed the hepatocyte or within the liver small room Excessive heme metabolism, from hemolysis or reabsorption of a large hematoma, arises in significant increases in bilirubin, which may overwhelm the conjugation proces and lead to a state of unconjugated hyperbilirubinemia. (10)

Hemolytic anemias usually proceed in mild bilirubin elevation, to about 5 mg by means of dL (85.5 [micro]mol per L) with or without clinical jaundice. Hemolytic anemias conclusion from abnormal red blood solitary abode; squalid survival times. These anemias may take place because of membrane abnormalities (eg hereditary spherocytosis) or enzyme abnormalities (eg glucose-6-phosphate dehydrogenase deficiency). Other etiologies of hemolysis include autoimmune disorders, remedys and defects in hemoglobin composition such as sickle cell disease and the thalassemias. (11)

INTRAHEPATIC CAUSES

Unconjugated Hyperbilirubinemia. Several disorders of enzyme metabolism affect the conjugation proces inside the hepatocyte, thereby impeding concluded conjugation. There are varying stages of unconjugated hyperbilirubinemia, depending upon the severity of enzyme inhibition with each disease.