1/6. Bilirubin photoisomerization products in serum and urine from a Crigler-Najjar type I patient treated by phototherapy.The relative compositions of the photoisomers of bilirubin-1X alpha (4Z, 15Z-bilirubin) in serum and urine of a patient with Crigler-Najjar type I syndrome treated by phototherapy are reported. High-performance liquid chromatography analysis reveals the presence of high serum levels of the configurational bilirubin photoisomer (4Z,15E-bilirubin) before the beginning of phototherapy (between 12 and 16% of the total bilirubin). The configurational photoisomer value increases during phototherapy with blue fluorescent lamps up to a photoequilibrium of about 25%, similar to that obtained in a bilirubin solution in vitro irradiated by the same lamps. This evidence suggests an inefficient serum excretion of the 4Z,15E-bilirubin. Indeed, its average half-life in serum of the Crigler-Najjar patient is found to be about 8 h. No detectable traces of the bilirubin structural isomer, lumirubin, are found in the serum. On the other hand, lumirubin represents the dominant bilirubin isomer excreted in the urine, as both 15Z and 15E configurations. Smaller amounts of 4Z,15E-bilirubin, 4E,15Z-bilirubin and native 4Z,15Z-bilirubin are observed in urine. The presence in urine of 4Z,15Z-bilirubin is probably due to a fast reversion of the configurational photoisomers to their native form. The half-life of the configurational photoisomers in urine kept at 38 degrees C is found to be of the order of a few minutes. Our study indicates that in Crigler-Najjar type I patients, mechanisms exist to excrete all bilirubin photoisomers. The lumirubin pathway seems to contribute markedly to bilirubin excretion in the urine, as occurs in jaundiced babies under phototherapy. However, the contribution of configurational isomers cannot be neglected.- - - - - - - - - - ranking = 1keywords = chromatography (Clic here for more details about this article) |
2/6. Responsiveness to phenobarbital in an adult with Crigler-Najjar disease associated with neurological involvement and skin hyperextensibility.We present the case of a 23-yr-old man who had had since birth marked and sustained unconjugated non-hemolytic hyperbilirubinemia and who had had several attacks of grand mal seizures. Analysis of serum bilirubin by diazoreactive methods showed serum levels of unconjugated bilirubin as high as 445 mumol/L that were not affected by phenobarbital administration. However, analysis of serum bile pigments by high-pressure liquid chromatography demonstrated marked decrease of unconjugated bilirubin after phenobarbital treatment (from 432.4 mumol/L to 291.0 mumol/L) associated with slight increase of bilirubin monoconjugates and disconjugates (from 0.25 mumol/L to 0.42 mumol/L). Furthermore, in the past few years the patient had exhibited striking skin hyperextensibility and diaphragm eventration. This case confirms that alkaline methanolysis-high-pressure liquid chromatography is the most reliable method for assessment of serum fraction bilirubin levels; that clinical parameters such as neurological signs do not unequivocally discriminate between type I and II Crigler-Najjar disease and that response to phenobarbital treatment remains the main diagnostic tool.- - - - - - - - - - ranking = 2keywords = chromatography (Clic here for more details about this article) |
3/6. Orthotopic liver transplantation for type I crigler-najjar syndrome.A neurologically normal 3-year-old girl with Type I crigler-najjar syndrome was successfully treated with orthotopic liver transplantation. Preoperative serum bilirubin concentrations as high as 31 mg per dl were not diminished with phenobarbital or phototherapy. Bilirubin fractionation of duodenal bile prior to transplantation revealed 87.1% unconjugated bilirubin and 12.9% monoconjugates as determined by alkaline methanolysis-high-performance liquid chromatography. Postoperatively, the serum bilirubin concentration quickly fell to normal. uridine diphosphate glucuronyl transferase activity in the recipient liver was not detectable. The gallbladder bile bilirubin concentration of 23.9 mg per dl was less than 15% of previously reported normal values. Since devastating kernicteric brain injury is the invariable outcome of Type I crigler-najjar syndrome, liver transplantation should be performed when phototherapy cannot maintain the serum bilirubin concentration at an unequivocally safe level.- - - - - - - - - - ranking = 1keywords = chromatography (Clic here for more details about this article) |
4/6. An unusual case of Crigler-Najjar disease in the adult. classification into types I and II revisited.We present the case of a 25-year-old man with Crigler-Najjar disease who had since birth a marked unconjugated hyperbilirubinemia without bilirubin overproduction, without any neurological involvement and in whom phenobarbital administration failed to produce any effect. Analysis of his biliary bile pigments on two occasions showed (i) a decrease excretion of bilirubin, as indirectly suggested by a high ratio of biliary bile acids over total bilirubin; (ii) an increase in unconjugated bilirubin IX alpha quantitated by thin-layer chromatography (TLC) following alkaline methanolysis and by direct extraction and TLC of the tetrapyrroles; (iii) a high proportion of bilirubin monoconjugates whereas the excretion of diconjugates was very low. classification of the present patient into Crigler-Najjar disease type I or II was not possible. The most striking and practical difference among the various cases of Crigler-Najjar disease remains the response to phenobarbital. Among cases of Crigler-Najjar disease which respond to enzyme induction and Gilbert's syndrome, the continuous spectrum suggests a common defect.- - - - - - - - - - ranking = 1keywords = chromatography (Clic here for more details about this article) |
5/6. serum and bile bilirubin pigments in the differential diagnosis of Crigler-Najjar disease.OBJECTIVE. To differentiate between Crigler-Najjar (CN) disease types 1 and 2. DESIGN. The patterns of serum bilirubins, bile pigment composition, and phenobarbital response were studied. patients. Three infants, affected by high serum unconjugated bilirubin concentrations, previously classified as type 1 CN. methods. serum and bile bilirubin pigment composition, both before and after phenobarbital (PB) treatment, were determined by alkaline methanolysis and high-pressure liquid chromatography. PB was given for at least 3 weeks by oral administration (5 mg/kg bw per day). RESULTS. No diconjugated bilirubin was found either before or after PB treatment in the serum of the three studied infants. In two patients traces of monoconjugated bilirubin were detected before PB therapy, and the ratio of conjugated/total bilirubin (percent) was increased by the PB response. In the third patient, traces of monoconjugated bilirubin appeared only after PB administration. However, the serum unconjugated bilirubin concentration decreased significantly only in the second patient, following the second cycle of PB treatment, leading to the diagnosis of type 2 CN. The analysis of the methyl ester derivatives of bile pigments was also performed on bile samples obtained in two patients by Entero-Test (R) both before and after PB treatment. An absolute increment in monoesterified bilirubin concentration was found after PB administration, although the percent concentration increased in one case and decreased in the other. No diesterified bilirubin was detected in the bile samples. CONCLUSIONS. The present results show that in types 1 and 2 CN disease it is possible to detect traces of monoconjugated but not diconjugated bilirubin both in serum and in bile. Whereas PB treatment is effective in slightly increasing the serum monoconjugated bilirubin concentration even in type 1 CN disease, the diagnosis of type 1 or 2 is based on finding a substantial decrease of serum unconjugated bilirubin following PB administration.- - - - - - - - - - ranking = 1keywords = chromatography (Clic here for more details about this article) |
6/6. Type II crigler-najjar syndrome with intrahepatic cholestasis.A 58-year-old Japanese man was admitted to our hospital with appendicitis and marked unconjugated hyperbilirubinemia (11.6 mg/dl). The jaundice worsened following appendectomy, and the direct-reacting bilirubin increased, probably due to the ceftizoxime administered postoperatively. Bilirubin diglucuronide was the main component of the serum direct-reacting bilirubin (51%) in serum measured by liquid chromatography. Because the discontinuation of ceftizoxime did not markedly improve the jaundice, epomediol, 200 mg tid, was administered orally. There was a marked decrease of serum bilirubin with an increase in the delta bilirubin/(conjugated bilirubin delta bilirubin) ratio. After improvement of jaundice to below the pre-surgical level (4.4 mg/dl), we analyzed the duodenal bile for bilirubin fractions; those showed a marked reduction in bilirubin diglucuronide and a marked increase in bilirubin monoglucuronide, which was consistent with type II crigler-najjar syndrome. A marked increase of bilirubin diglucuronide in serum of this patient during cholestasis suggests that bilirubin conjugation proceeds in this syndrome when excretion of conjugated bilirubin decreases.- - - - - - - - - - ranking = 1keywords = chromatography (Clic here for more details about this article) |