Increased conjugated hyperbilirubinemia is the hallmark for diagnosing<unk> . There is no distinct black pigmentation of the liver as seen in a similar, Dubin-Johnson Syndrome. Genes, SLCO1B1 and SLCO1B3 that result in complete functional deficiencies of both protein products (OATP1B1 and OATP1B3, respectively), are also present.<unk>  is largely a diagnosis of exclusion. Serological abnormalities in<unk>  only include elevated total serum bilirubin (typically elevated between 2 to 5 mg/dL but may be as high as 20 mg/dL). Most of the time, alanine aminotransferase, aspartate aminotransferase, gamma-glutamyl transferase, and alkaline phosphatase levels are normal, but mild elevations can be seen. If any of these lab values are markedly elevated, investigation for other, more serious conditions is warranted. Imaging studies cannot diagnose<unk>  but can help rule out other diseases that cause hyperbilirubinemia. For example, ultrasound of the liver and the biliary tree can help investigate the causes of extra-hepatic biliary obstruction. The gallbladder is visualized on oral cholecystography in<unk>  while it is not visualized in Dubin Johnson syndrome. Ultimately, the best method of diagnosing the disease is the analysis of urine coproporphyrin excretion. The total urine coproporphyrin excretion in<unk>  has a 2- to 5-fold elevation, with 65% constituting coproporphyrin I.
Rotor syndrome
Gilbert's syndrome  Gilbert's syndrome  1
GRACILE syndrome
ZTTK syndrome
LIG4 syndrome
ATR-16 syndrome
MEDNIK syndrome
GAPO syndrome