Hyperbilirubinemia conjugated

Obstruction in the BiiiaryTree Is the Commonest Cause of Conjugated Hyperbilirubinemia... 

Conjugated hyperbilirubinemia commonly results from blockage of the hepatic or common bile ducts, most often due to a gallstone or to cancer of the head of the pancreas. Because of the obstruction, bilirubin diglu-curonide cannot be excreted. It thus regurgitates into the hepatic veins and lymphatics, and conjugated bilirubin appears in the blood and urine (choluric jaundice). 

The term cholestatic jaundice is used to include all cases of extrahepatic obstructive jaundice. It also covers those cases of jaundice that exhibit conjugated hyperbilirubinemia due to micro-obstruction of intrahepatic biliary ductules by swollen, damaged hepatocytes (eg, as may occur in infectious hepatitis). 

This benign autosomal recessive disorder consists of conjugated hyperbilirubinemia in childhood or during adult life. The hyperbilirubinemia is caused by mutations in the gene encoding MRP-2 (see above), the protein involved in the secretion of conjugated bilirubin into bile. The centrilobular hepatocytes contain an abnormal black pigment that may be derived from epinephrine. 

This is a rare benign condition characterized by chronic conjugated hyperbilirubinemia and normal liver histology. Its precise cause has not been identified, but it is thought to be due to an abnormality in hepatic storage. 

Jansen PL, Peters WH, Lamers WH. Hereditary chronic conjugated hyperbilirubinemia in mutant rats caused by defective hepatic anion transport. Hepatology 1985 5(4) 573—579. 

Kurisu H, Kamisaka K, Koyo T, Yama-suge S, Igarashi H, Maezawa H et al. Organic anion transport study in mutant rats with autosomal recessive conjugated hyperbilirubinemia. Life Sci 1991 ... 

Hosokawa S, Tagaya O, Mikami T, et al. A new rat mutant with chronic conjugated hyperbilirubinemia and renal glomerular lesions. Lab Anim Sci 1992 42 27-34. 

Liver disease is commonly associated with oq-antitrypsin deficiency and may develop at any age. Approximately 10% to 20% of oq-antitrypsin-deficient infants with the phenotype PIZZ are first seen for neonatal cholestatic liver disease, as was the child in this case report. Conjugated hyperbilirubinemia and he-... 

Because only conjugated bihrubin is excreted in urine, its presence indicates conjugated hyperbilirubinemia. The most commonly used method for detecting bilirubin in urine involves the use of a dipstick impregnated with a diazo reagent. Dipstick methods can detect bilirubin concentrations as low as 0.5mg/dL. 

Rotor syndrome is another form of conjugated hyperbilirubinemia similar to Dubin-Johnson syndrome but without pigment in the liver. The gallbladder is seen on intravenous cholecystography. Total urinary coproporphyrins are elevated, with about two thirds being coproporphyrin I. The prognosis is excellent. 

Disorders that cause jaundice in the neonate are classified as either unconjugated or conjugated hyperbilirubinemia (see Box31-l). " ... 

Conjugated Hyperbilirubinemia (Cholestasis) Decreased Secretion of Conjugated Bilirubin into Canaliculi... 

Conjugated hyperbilirubinemia is seen fairly often in the newborn as a complication of parenteral nutrition. 

Takenaka, O., Horie, T., Kobayashi, K., Suzuki, H. and Sugiyama, Y. (1995) Kinetic analysis of hepatobiliary transport for conjugated metabolites in the perfused liver of mutant rats (EHBR) with hereditary conjugated hyperbilirubinemia. Pharmaceutical Research, 12, 1746-1755. 

Kitamura, T, Jansen, P., Hardenbrook C., Kamimoto, Y, Gatmaitan, 1.., and Arias, l.M, (1990) Defective ATP-dependent bile canalicular transport of organic anions in mutant (TR ) rats with conjugated hyperbilirubinemia. Proceedings of the Natiorud Academy of Sciences of the United States of America. 87 (9), 3557—3561. 

Jansen, P.L., Groothuis, G.M., Peters, W.H., and Meijer, D.F. (1987) Selective hepatobiliary transport defect for organic anions and neutral steroids in mutant rats with hereditary-conjugated hyperbilirubinemia. Hepatology, 7 (1), 71-76. 

Conjugated hyperbilirubinemias are due to intra- or extra-hepatic reduction to bile flow (cholestasis) with spillage of conjugated bilirubin into the bloodstream, which may occur from injury to the endothelial cells lining bile ductules or from reverse pinocytosis, by the hepatocytes. Since the serum bilirubin is mostly the water-soluble glucuronide, bilirubinuria is usually present. 

Once these causes of jaundice have been excluded, neonatal hepatitis, biliary atresia (BA) or duct paucity syndromes will account for more than two thirds of the remaining cases of conjugated hyperbilirubinemia in the neonate. In conjunction with nuclear medicine, US is the primary imaging modality for differentiating among these diseases and differentiation is important, as surgery is the treatment for BA but not for the other entities (Kelly 1999 Mortele et al. 2006 Gazelle et al. 1998). 

A full-term neonate weight, 3.45 kg, was referred at 60 days of age for surgery for short bowel secondary to a mid-gut volvulus. He was given parenteral nutrition and after 4 months developed conjugated hyperbilirubinemia. He... 

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