DETERMINATION OF PORPHYRINS IN BILE USING HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHY AND SOME CLINICAL-APPLICATIONS

A simple and fast HPLC method for the determination of porphyrins in b ile without extraction is described. Porphyrins were determined in bil e from control subjects and from patients after orthotopic liver trans plantation, including three patients with erythropoietic protoporphyri a. It was found that: 1) coproporphyrin I is the predominant porphyrin in bile of controls, accompanied by some coproporphyrin III and proto porphyrin, whereas protoporphyrin mostly but not always is the predomi nant porphyrin in the bile of erythropoietic protoporphyria patients. In two of the three erythropoietic protoporphyria patients, the bile c ontained a hundred times more protoporphyrin than that of non-porphyri c orthotopic liver transplantation patients. The third erythropoietic protoporphyria patient remained cholestatic and was unable to excrete sufficient amounts of protoporphyrin. 2) All investigated bile samples contained no secondary porphyrins derived from protoporphyrin, i. e. no deutero-, pempto-, or mesoporphyrin. Even when extracts of bile and serum were concentrated fifty to a hundred times, no traces of deuter o-, pempto- and mesoporphyrin were detected. This complete absence of secondary porphyrins suggests that an enterohepatic circulation of dic arboxylic porphyrins from the distal gastrointestinal tract does not e xist. 3) The HPLC chromatograms contain peaks from unknown compounds. No correlation between porphyrins and these compounds was found. Porph yrin profiles were followed in the bile of some orthotopic liver trans plantation patients. Three episodes are recognizable. During the first three days after orthotopic liver transplantation there is a very hig h coproporphyrin excretion. There is then a lag of one to three weeks, in which no or very low porphyrin concentrations are detectable, foll owed by the restoration of normal biliary porphyrin patterns.