A benign form of mixed jaundice with conjugated (50%) and unconjugated (50%) bilirubin. Normal hepatic function and histology probably related to a defective binding and storage protein for bilirubin in liver cells. It also features a coproporphyrinuria associated with a strong reduced liver uptake of many pharmaceutical compounds.
Hyperbilirubinemia Rotor Type.
This medical condition was first described by Arturo Belleza Rotor (1907-1988), a Filipino Internist.
The prevalence of the disease remains unknown.
Benign, familial, unconjugated, nonhemolytic hyperbilirubinemia. Jaundice caused by impaired excretion or storage of conjugated bilirubin. This syndrome is caused by digenic inheritance of homozygous mutations in the SLCO1B1 and SLCO1B3 genes, which are located on 12p12.1 and 12p12.2, respectively. These genes code the polypeptides OATP1B1 and OATP1B3, which serve as transporters for organic anions and thus participate in the elimination of toxic glucuronoconjugates.
Routine blood tests reveal conjugated hyperbilirubinemia. Albumin, transaminases, alkaline phosphatase, and prothrombin time are normal. Gross and microscopic examinations of the liver are normal. Bromosulphthalein transport is reduced. Urinary coproporphyrin level I is 2 to 5 times greater than normal and used to differentiate Rotor Syndrome from Dubin-Johnson Syndrome.
Benign hyperbilirubinemia of no clinical importance. No identified precipitating factors. No specific treatment.
Avoid alcohol and hepatotoxic drugs and drugs that can displace bilirubin from albumin (eg, cephalosporin).
Other conditions to be considered
The hereditary hyperbilirubinemias include firstly those predominantly unconjugated hyperbilirubinemia, ie, ☞Gilbert or Arias Syndrome, ☞Crigler-Najjar Syndrome type I, and ☞Crigler-Najjar Syndrome type II, and secondly those resulting in predominantly conjugated hyperbilirubinemia: ☞Dubin-Johnson Syndrome, ☞Rotor Syndrome, and several forms of Intrahepatic Cholestasis.
☞Gilbert Syndrome: Characterized by normal liver function tests of the usual type, normal liver histology, delayed clearance of bilirubin from the blood, and mild jaundice that tends to fluctuate in severity, particularly after fasting. This disorder is difficult to distinguish from prolonged posthepatic hyperbilirubinemia. Gilbert Syndrome is distinguished by the lack of morbidity in patients and by a lower total serum bilirubin level, ranging from 1 to 6 mg/dL.
☞Crigler-Najjar Syndrome: Presents in two forms: Type I and Type II. Type I is characterized by a deficiency in hepatic glucuronyltransferase activity. Hyperbilirubinemia is severe, with total serum bilirubin levels ranging from 20 to 45 mg/dL most often associated with kernicterus. Type I patients do not respond to phenobarbital treatment and only traces of bilirubin glucuronides can be found in their bile. It is inherited by autosomal recessive transmission. ...