Effects of corticosteroids on bilirubin metabolism in patients with Gilbert's syndrome

Efficacy and Safety of Steroid Therapy for Posttransplant Hyperbilirubinemia Caused by Early Allograft Dysfunction: A Randomized Controlled Trial

BACKGROUND Hyperbilirubinemia is a common event that occurs after liver transplantation. Hyperbilirubinemia is usually caused by early allograft dysfunction. Glucocorticoid is widely used for immunosuppression, but few studies have analyzed the effects of steroid therapy on posttransplantation hyperbilirubinemia. The aim of this study was to assess whether glucocorticoid was beneficial in treating hyperbilirubinemia caused by early allograft dysfunction. MATERIAL AND METHODS Patients with postoperative hyperbilirubinemia (those with conditions such as biliary complications and rejections were excluded) were randomly assigned, in a 2: 1 ratio, to the steroid and control groups. Patients in the steroid group were treated with glucocorticoid combined with ursodeoxycholic acid, whereas patients in the control group were only treated with ursodeoxycholic acid. The primary endpoint was decrease in bilirubin and the secondary endpoint was safety. RESULTS From 1st June 2016 to 30th April 2018, 40 patients were enrolled into the steroid group, and 20 were enrolled into the control group. Donor, recipient, and operative data were similar between the 2 groups. The decrease in bilirubin levels in the steroid group was significantly greater than that in the control group on the first day after the intervention was finished (9.25±1.30 mg/dL vs. 3.11±1.45 mg/dL, p=0.005), and after 2 weeks (15.01±1.20 mg/dL vs. 8.88±1.98 mg/dL, p=0.007). The steroid group did not have a higher complication rate but it did have a shorter postoperative hospital stay than in the control group. CONCLUSIONS Low-dose steroid therapy was effective and safe for treating hyperbilirubinemia caused by early graft dysfunction, and it improved liver function.

Bile acid receptors as targets for drug development

The intracellular nuclear receptor farnesoid X receptor and the transmembrane G protein-coupled receptor TGR5 respond to bile acids by activating transcriptional networks and/or signalling cascades. These cascades affect the expression of a great number of target genes relevant for bile acid, cholesterol, lipid and carbohydrate metabolism, as well as genes involved in inflammation, fibrosis and carcinogenesis. Pregnane X receptor, vitamin D receptor and constitutive androstane receptor are additional nuclear receptors that respond to bile acids, albeit to a more restricted set of species of bile acids. Recognition of dedicated bile acid receptors prompted the development of semi-synthetic bile acid analogues and nonsteroidal compounds that target these receptors. These agents hold promise to become a new class of drugs for the treatment of chronic liver disease, hepatocellular cancer and extrahepatic inflammatory and metabolic diseases. This Review discusses the relevant bile acid receptors, the new drugs that target bile acid signalling and their possible applications.

Unusual early presentation of Gilbert syndrome in pediatric recipients of liver transplantation

BACKGROUND

Gilbert syndrome as a rule becomes manifest in adolescence or in early adulthood; it may be transferred by the donor to orthotopic liver transplant (OLT) recipients.

METHODS

We examined the frequency of Gilbert syndrome in 46 OLT pediatric recipients who had a follow-up of 1 year or more. Diagnostic criteria included unexplained chronic or recurrent unconjugated hyperbilirubinemia; its increase after reduced caloric intake plus prolonged fasting, without changes of the proportion of conjugated bilirubin; and high relative amounts of serum unconjugated bilirubin IXa and prevalence of the monoglucuronide over the diglucuronide.

RESULTS

Of the 46 patients, 42 had normal bilirubin values. Only four otherwise healthy OLT recipients showed hyperbilirubinemia and normal conjugated fractions. Liver donors had been four men. Hyperbilirubinemia persisted with a fluctuating pattern for the whole follow-up after OLT in all. Total bilirubin level in blood samples obtained after reduced caloric intake and prolonged fasting became notably higher than basal values, whereas the proportion of conjugated bilirubin remained stable. High relative amounts of unconjugated bilirubin IXa and prevalence of the monoglucuronide over the diglucuronide were found. Finally, DNA from liver donors' lymphocytes was available for one jaundiced and two nonjaundiced patients: tests for abnormalities in the promoter region of the gene for the enzyme bilirubin uridine diphospho-glucuronosyltransferase were in agreement with a diagnosis of GS in the former one,

CONCLUSIONS

Gilbert syndrome may have an unusual early presentation in pediatric OLT recipients.

Doxorubicin dosage guidelines in a patient with hyperbilirubinemia of Gilbert's syndrome

OBJECTIVE

To reconcile dosage modification guidelines for doxorubicin in a patient with hyperbilirubinemia of Gilbert's syndrome (GS).

CASE SUMMARY

A 62-year-old white man with concurrent diagnoses of large-cell non-Hodgkin's lymphoma and GS was treated with standard doses of a doxorubicin-containing chemotherapy regimen. No increase of end-organ toxicity was observed during four treatment cycles.

DISCUSSION

The relative prevalence of GS coupled with the rising incidence of non-Hodgkin's lymphoma increases the probability that both disorders will be present in the same individual. A MEDLINE search (1966 through July 1997) revealed little, and often conflicting, information pertaining to drug metabolism and disposition in GS. In addition, no information has been reported regarding the metabolic fate of doxorubicin in these patients. It is important to emphasize that the lack of enhanced extramedullary toxicity in this patient is not conclusive evidence that the hepatic abnormality of GS had no effect on doxorubicin metabolism.

CONCLUSIONS

Based on information regarding mechanisms for hepatic clearance, dosage modification of doxorubicin may not be necessary in hyperbilirubinemia of GS.

The nicotinic acid test in constitutional conjugated hyperbilirubinemias and effects of corticosteroid

The nicotinic acid test was performed in 5 patients with Dubin-Johnson syndrome, 5 with Rotor syndrome and 13 with Gilbert's syndrome. The increment in serum bilirubin concentration and bilirubin retention 5 hr later differed; the proportion of conjugated bilirubin in the increment of total bilirubin in Dubin-Johnson and Rotor syndromes was greater than in Gilbert's syndrome. These observations suggest that the nicotinic acid test reflects, in part, impaired biliary excretion of conjugated bilirubin. The results did not differentiate the two conjugated hyperbilirubinemias. The nicotinic acid test was also performed before and after corticosteroid treatment in four patients with Dubin-Johnson or Rotor syndrome. Although serum total and unconjugated bilirubin concentrations were reduced by corticosteroids, no significant change occurred in the parameters of the nicotinic acid test, suggesting that corticosteroids may enhance uptake of bilirubin without significantly altering biliary excretion of conjugated bilirubin.

Effect of plasma exchange and immunosuppression on Rho(D), viral, and bacterial antibody titers in Rh-immunized women

Pharmacologic immunosuppression and plasmapheresis have both been advocated as adjunctive methods of treatment for Rh immunization, but a combined regimen of the two has not been attempted. We treated four nonpregnant, severely Rh-sensitized female volunteers with intensive plasma exchange and either promethazine 150 mg or prednisone 60 mg per day in an attempt to remove circulating anti-Rho(D) and prevent further synthesis of the antibody. Each patient received three or four exchanges. The Rho(D) antibody titer decreased by at least one dilution immediately following 11 of 14 plasma exchanges and was ultimately lowered at least two dilutions in all patients. In one case the titer was reduced from 1:512 to 1:16, and a low titer was maintained for the duration of treatment. However, this regimen could increase the risk of infection for a mother and/or infant, as evidenced by the concomitant lowering of viral and bacterial antibody titers in these women.