Unusual hyperbilirubinemia associated with bacterial pneumonia and acute myeloid leukemia

A 77-year-old man with pneumonia associated with acute myeloid leukemia was introduced to the hepatology unit at our hospital for hyperbilirubinemia. He had been suffering from a high fever because of pneumonia. He was icteric and his serum concentrations of total and direct bilirubin were 13.1 and 7.9 mg/dl, respectively. However, the other standard biochemical examinations for hepatic function, such as serum concentrations of aspartate aminotransferase, alanine aminotransferase, gamma-glutamyl transpeptidase and alkaline phosphatase were normal except for lactate dehydrogenase. Lactate dehydrogenase isoenzyme analysis revealed that the high concentration was derived from leukemia cells. Ultrasonography of the abdomen revealed no abnormality in the liver or biliary tract. Administration of antibiotics for pneumonia decreased the serum bilirubin concentration, however, he died because of respiratory failure caused by the progression of pneumonia at 33 days after the admission. It was suggested that a disturbance in the bilirubin metabolism without hepatocyte necrosis or mechanical cholestasis might be involved in the pathogenesis of hyperbilirubinemia in patients with infectious diseases.