Generally, a high serum creatinine level means that your kidneys aren't working well. Your creatinine level may temporarily increase if you're dehydrated, have a low blood volume, eat a large amount of meat or take certain medications. The dietary supplement creatine can have the same effect. Higher than normal levels of direct bilirubin in your blood may indicate your liver isn't clearing bilirubin properly, for example, because of a blocked bile duct. Elevated levels of indirect bilirubin may indicate other problems. One common, and harmless, cause of elevated bilirubin is Gilbert's syndrome, a deficiency in an enzyme that helps break down bilirubin. Your doctor may order further tests to investigate your condition.