Screening for occult blood by means of guaiac tests has an unsatisfactory sensitivity for the detection of colorectal neoplasms. To increase sensitivity and specificity the immunological determination of human hemoglobin and albumin in feces has been developed. The validity of analyzing only two samples from one bowel movement of either test is not known.An immunological determination of human fecal hemoglobin and albumin using luminescence immunoassays (LIA) was performed in 739 patients with gastrointestinal complaints before scheduled colonoscopy. Each patient collected two 1 ml samples from one stool. There were no dietary restrictions.The sensitivity for detecting colorectal carcinomas was 95.3% (95% confidence interval 84.2-99.4%) with hemoglobin and 67.4% (95% confidence interval 51.2-80.9%) with albumin. The sensitivity for detecting large adenomatous polyps was 62.9% (95% confidence interval 50.5-74.1%) with hemoglobin and 32.9% (95% confidence interval 22.1-45.1%) with albumin. The specificity was 97% for hemoglobin, 96% for albumin and 94% for the combined test.The immunological determination of fecal hemoglobin is superior to albumin and has a better sensitivity for the detection of colorectal neoplasms than that reported for guaiac tests, even if two samples from one bowel movement are examined. The immunological determination of fecal hemoglobin should therefore be evaluated for use in colorectal cancer screening.
In patients with cirrhosis of the liver elevated bilirubin concentrations in the plasma could be the result of decreased bilirubin excretion or an overproduction of bilirubin with insufficient excretion of the increased amounts of bilirubin. Under steady state conditions with constant serum bilirubin concentrations bilirubin synthesis equals biliary and urinary bilirubin excretion. In the present study in 10 healthy volunteers and 11 patients with alcoholic cirrhosis of the liver and serum bilirubin concentrations of 7.0 +/- 1.9 mg/dl the biliary excretion of bilirubin was studied by the intestinal perfusion method and compared with the excretion of bile lipids. Biliary excretion of bilirubin in the cirrhotics was 38.7 +/- 8.8 mumol/h, the 10 healthy controls excreted 17.9 +/- 0.9 mumol/h bilirubin. Only minor amounts of bilirubin were excreted in urine. In 4 of the 11 cirrhotics 51Cr-red blood cell half-lives were studied revealing ongoing hemolysis. Bilirubin production calculated from red cell life span was identical to biliary excretion of bilirubin with an error less than 5%. The data indicate that in patients with alcoholic cirrhosis of the liver serum concentrations of bilirubin may be elevated due to overproduction of bilirubin and a concomitant decrease of the biliary transport capacity of bilirubin.
