Case Series: Hyperbilirubinemia under elexacaftor/tezacaftor/ivacaftor in the presence of Gilbert's syndrome.

Liver-related side effects are a known complication of treatment with elexacaftor/tezacaftor/ivacaftor (ETI) for cystic fibrosis (CF). Gilbert's syndrome is caused by a genetic mutation that reduces activity of the enzyme UDP glucuronosyltransferase 1 polypeptide A1 (UGT1A1), causing elevated levels of unconjugated bilirubin in the blood and duodenal bile. The presence of Gilbert's syndrome and CF might represent additive risk factors for liver-related adverse events during ETI treatment. This case series describes six people with CF (pwCF) in whom previously unknown Gilbert's syndrome was unmasked after initiation of treatment with ETI. Although all patients had some level of hepatic dysfunction and/or elevated levels of bilirubin after initiation of ETI, the clinical course varied. Only one patient had to stop ETI therapy altogether, while the others were able to continue treatment (some at a reduced dosage and others at the full recommended daily dosage). All patients, even those using a lower dosage, experienced clinical benefit during ETI therapy. Gilbert's syndrome is not a contraindication for ETI therapy but may be mistaken for a risk factor for liver-related adverse events in pwCF. This is something that physicians need to be aware of in pwCF who show liver adverse events during ETI therapy.

Slow increase of bilirubin concentration during administration of lenalidomide, bortezomib and dexamethasone for multiple myeloma (unmasking previously undiagnosed Gilbert syndrome) and disappearance of necrobiotic xanthogranuloma after complete remission of multiple myeloma.

BACKGROUND: Lenalidomid ranks among immunomodulatory drugs. There are a few of the more common side effects, like a higher risk of venous trombembolism or diarrhea. Other side effects are rare. The hyperbilirubinemia described in this article can be assigned to them. In our case, the increase of bilirubin was associated with unrecognized Gilbert syndrome. CASE DESCRIPTION: We report a patient with multiple myeloma and necrobio-tic xanthogranuloma (NXG) of the skin and liver. After the treatment with bortezomib, lenalidomid and dexamethasone, complete remission was attained after 4 cycles with decrease of monoclonal immunoglobulin to an unmeasurable concentration. At the same time, the dis-appearance of cutaneous and hepatic lesions of NXG on FDG-PET/CT was evident. The administration of bortezomib was stopped after 8 cycles and only continued with lenalidomide as a maintenance therapy. However, after four cycles of this therapy, bilirubin increased above the upper limit and the increase continued till the 11th month of lenadomide administration, when bilirubin reached the highest concentration of 75 μmol/l (more than the three-fold of the upper limit, grade III toxicity). The patient had asymptomatic hyperbilirubinemia with no underlying liver disease or renal impairment while being on lenalidomide therapy. Genetic studies proved mutation; insertion in the promotor gene UGT1A1 typical for Gilbert syndrome. Hyperbilirubinemia may be attributed to the unmasking of previously undia-gnosed Gilbert syndrome. Therefore, the therapy with lenalidomide was interrupted after 11 months. The bilirubin level decreased after the discontinuation of the drug. CONCLUSION: NXG disappeared after fulfilling complete remission of multiple myeloma with disappearance of monoclonal immunoglobulin. This observation supports the hypothesis that monoclonal immunoglobulin has a crucial role in the ethiopathogenesis of NXG and suggests the treatment of monoclonal gammopathy if present in a patient with NXG, hoping that this will result in xantogranuloma disappearance.

Hepatotoxicity caused by mebendazole in a patient with Gilbert's syndrome.

WHAT IS KNOWN AND OBJECTIVE: Mebendazole (MBZ) is a broad-spectrum antihelminthic agent of the benzimidazole type. Although MBZ has been reported to cause hepatic injury, case reports of severe hepatic injury are very rare. We report a case of severe hepatitis after administration of MBZ in a patient with Gilbert's syndrome affected by pinworms infestation. CASE SUMMARY: Differently from other cases of hepatitis due to MBZ reported in the scientific literature, our patient received standard doses of MBZ for a short period of time. After 18 days from the start of therapy, he developed hepatomegaly, and increases in hepatic enzymes and bilirubin. Hepatic enzymes returned to normal over the following 5 weeks. WHAT IS NEW AND CONCLUSION: This is the first case report of important liver injury after administration of MBZ in a patient with Gilbert's syndrome. We suspected that a diminished hepatic glucuronidation of MBZ due to the reduced activity of the glucuronosyltransferase enzyme in our patient could have caused an increase in unconjugated toxic metabolites of MBZ and the consequent liver damage.

Homeopathy-medicine induced severe alcoholic hepatitis.

We present a teetotaler with compensated non-alcoholic fatty-liver-disease related cirrhosis who presented with acute worsening of his chronic liver disease. The acute event was not discernible even after extensive work up and finally a transjugular liver biopsy revealed features suggestive of severe alcoholic hepatitis. The patient and the family denied occult alcohol use when questioned over multiple times and finally, the culprit 'alcohol' was found to be the homoeopathy medicines that the patient was consuming over a month for treatment of Gilbert's syndrome. We retrieved and tested the homoeopathy drug for alcohol content and found an alarming 18% ethanol in the same, confirming our diagnosis.

Oncology Drug Dosing in Gilbert Syndrome Associated with UGT1A1: A Summary of the Literature.

Gilbert syndrome (GS) is a hereditary condition that affects ~10% of the population. It is characterized by intermittent, unconjugated hyperbilirubinemia in the absence of hepatocellular damage and hemolysis. Although GS is often described as a benign laboratory finding, it may alter drug metabolism by decreasing the ability to conjugate drugs. Genetic polymorphisms, specifically the UGT1A1*28 allele, may reduce glucuronidation by 30% that severely impacts the ability to metabolize certain medications. Antineoplastic agents used in oncologic settings have toxic side effects, and alterations in metabolism may result in severe or even life-threatening toxicities. Many of the drug monographs provided by manufacturers contain dose adjustment parameters for hepatic function, using serum bilirubin as a surrogate marker. However, in patients with GS, hepatic function remains normal in the setting of hyperbilirubinemia, and scant literature is available to provide guidance on empirical dosage adjustment. In this review, we conducted a literature search of routinely used oncology medications and assessed the need for empirical dose adjustments in the setting of GS.

Outcome and toxicities associated to chemotherapy in children with acute lymphoblastic leukemia and Gilbert syndrome. Usefulness of UGT1A1 mutational screening.

BACKGROUND: Acute lymphoblastic leukemia (ALL) is the most frequent cancer in childhood. Although intensive chemotherapy has improved survival in those patients, important side effects, including hyperbilirubinemia, are frequent. Gilbert syndrome (GS) is a frequent condition that causes a reduction in glucuronidation and intermittent hyperbilirubinemia episodes. This could provoke a greater exposure to some cytotoxic agents used in ALL, increasing the risk of toxicity. On the other hand, unexplained hyperbilirubinemia could lead to unnecessary modifications or even treatment withdrawals, which could increase the risk of relapse, but data regarding this in ALL pediatric population are scarce. METHODS: Retrospective study to analyze toxicity, outcome and treatment modifications related to GS in children diagnosed with ALL. RESULTS: A total of 23 of 159 patients were diagnosed with GS. They had statistically higher hyperbilirubinemias during all treatment phases (P < 0.0001) and a slower methotrexate clearance when it was administered during a 24-hr infusion at high doses (patients with GS: 74 hr ± 19 vs. patients without GS: 64 hr ± 8; P < .002). However, no relevant toxicity or delays in treatment were found in them. Finally, changes in treatment due to hyperbilirubinemia were only done in 5 patients with GS. CONCLUSIONS: Differences in outcome were not found in patients with GS. Universal screening for GS appears to be not necessary in pediatric patients with ALL. However, when hyperbilirubinemia is observed, it must be rule out in order to avoid unnecessary changes in treatment.

Hepatotoxicity of isotretinoin in patients with acne and Gilbert's syndrome: a comparative study.

OBJECTIVES: The objective of our follow-up study is to evaluate liver function tests (LFTs) and lipid profiles in patients with Gilbert's syndrome treated with isotretinoin because of severe acne. SETTING: Dermatology outpatient clinics of three regional hospitals of Jaén (Spain). PARTICIPANTS: Over 4 years, we included all patients diagnosed with severe acne. Only 37 patients were identified, of which 11 had Gilbert's syndrome. INTERVENTIONS: All patients were treated with isotretinoin and followed-up in our outpatient clinics after 10 and 20 weeks. Patients were subjected to an interview questionnaire which included data on age, gender, complete blood count, coagulation profile, fasting blood glucose, LFTs and lipid profiles. Data and results of patients with severe acne and Gilbert's syndrome were compared with those of 26 patients with only severe acne (control group). PRIMARY OUTCOME: Blood analyses were repeated in the follow-up visits. RESULTS: In patients with Gilbert's syndrome, bilirubin levels showed substantial decrease over the 20-week follow-up, with more decrease after 10 weeks. None of the control group patients had significant increase in total bilirubin levels after 10 and 20 weeks of follow-up. Liver enzymes were maintained within normal levels in both groups. Both study groups did not show significant pathological increase in lipid profile levels. LDL levels were increased in the two study groups, but this increase was less substantial in patients with Gilbert's syndrome. CONCLUSIONS: Our preliminary results suggest that oral isotretinoin could be an effective, safe treatment for patients with Gilbert's syndrome, and may lower bilirubin levels in the first 10 weeks of treatment. Limitations of the study include the small numbers of participants and the fact that it is restricted to one region of Spain.

Severe unconjugated hyperbilirubinaemia: one and one makes three?

A 38-year-old housewife presented with a 3-month history of gradually progressive fatigue and deepening jaundice as well as a history of mild fluctuating jaundice since childhood. General examination revealed an obvious icterus. Systemic examination was normal. Laboratory tests confirmed unconjugated hyperbilirubinaemia. Further evaluation yielded a diagnosis of vitamin B12 deficiency on a background of Gilbert's syndrome.

Genetic characterization to improve interpretation and clinical management of hepatotoxicity caused by tyrosine kinase inhibitors.

Tyrosine kinase inhibitors (TKIs) represent important therapeutic alternatives to, or combinations with, traditional cytotoxic chemotherapy. Despite their selective molecular targeting and demonstrated clinical benefit, TKIs produce a range of serious adverse events, including drug-induced liver injury, that require careful patient management to maintain treatment benefit without harm. Genetic characterization of serious adverse events can identify mechanisms of injury and improve safety risk management. This review presents pharmacogenetic comparisons of two approved TKIs, lapatinib and pazopanib, which reveal different mechanisms of injury and inform the characteristics and risk of serious liver injury in treated patients. The data presented demonstrate the utility of genetic studies to investigate drug-induced liver injury and potentially support its management in patients.

Lapatinib-induced liver injury characterized by class II HLA and Gilbert's syndrome genotypes.

Lapatinib is a clinically important component of the treatment for HER2-positive metastatic breast cancer and has an acceptable safety profile. Lapatinib-associated Hy's Law cases have been characterized using human leukocyte antigen (HLA) DQA1*02:01/DRB1*07:01 and Gilbert's syndrome UGT1A1*28/*28 genotypes. The HLA-positive cases had higher alanine aminotransferase (ALT) elevation, whereas the HLA-negative cases had a higher incidence of Gilbert's syndrome. The findings of our study, which extend this HLA association to lapatinib-associated serious liver injury, emphasize the importance of Gilbert's syndrome in the interpretation of Hy's Law and may lead to methods for enhancing patient safety.

Acetaminophen administration in a patient with Gilbert's syndrome.

The patient was an 8-year-old Japanese girl with Gilbert's syndrome (GS). Based on the DNA analysis, she was homozygous for a T-to-G transversion at nucleotide position 1456 in the UGT1A1 gene, leading to the substitution of aspartate for tyrosine at position 486 of the UGT1A1 enzyme. Because this mutation is located in an exon common to UGT1A genes, all the UGT1A enzymes may be affected. It is well-known that UGT1A1, UGT1A6 and UGT1A9 enzymes glucuronidate acetaminophen. To evaluate acetaminophen tolerance in the patient, serum acetaminophen levels were determined after oral administration of acetaminophen (15 mg/kg). The maximum serum acetaminophen level reached (12.8 µg/mL) was far below the toxic level. The finding suggested that the usual therapeutic dose of acetaminophen is safe for the GS patient. The combination of mutation analysis in UGT1A1 and acetaminophen loading test may be useful to avoid adverse effect in GS patients.

Hyperbilirubinemia syndromes (Gilbert-Meulengracht, Crigler-Najjar, Dubin-Johnson, and Rotor syndrome).

Hyperbilirubinemia is an important clinical sign that often indicates severe hepatobiliary disease of different etiologies. Inherited non-haemolytichyperbilirubinemic conditions include Dubin-Johnson, Rotor, and Gilbert-Meulengracht syndromes, which are important differential diagnoses indicating benign disease that require no immediate treatment. Dubin-Johnson and Rotor syndromes are rare, exhibit mixed direct and indirect hyperbilirubinemia as well as typical profiles or urinary coproporphyrin excretion. Gilbert-Meulengracht disease leads to unconjugated hyperbilirubinemia because of impaired glucuronidation activity, and is part of a spectrum of genetic variants also encompassing fatal Crigler-Najjar syndrome. Gilbert-Meulengracht syndrome can be diagnosed by clinical presentation, biochemistry and genotyping, and carries significance regarding the disposition towards drug-associated toxicity. In addition, the precise diagnosis of these inherited hyperbilirubinemic syndromes avoids unnecessary invasive procedures for suspected more severe hepatobiliary disease.

Correction of venlafaxine- and duloxetine-induced transaminase elevations with desvenlafaxine in a patient with Gilbert's syndrome.

Recent reviews have questioned whether the serotonin-norepinephrine reuptake inhibitor (SNRI) desvenlafaxine succinate offers any practical clinical advantages over existing SNRIs. The following case is one instance where it appears that this SNRI offers unique safety and benefit. Presented is a case report of a patient with Gilbert's syndrome, longstanding social phobia, and more recent depressive disorder not otherwise specified, who was found to have elevated liver transaminases when prescribed both duloxetine and venlafaxine. The patient subsequently responded to desvenlafaxine but without liver abnormalities. In this patient with Gilbert's Syndrome, desvenlafaxine's lack of metabolism through the cytochrome P450 (CYP) 2D6 pathway may explain the avoidance of these abnormalities and thus suggests a possible therapeutic role for this SNRI in similarly susceptible patients.

Pegvisomant-induced liver injury is related to the UGT1A1*28 polymorphism of Gilbert's syndrome.

CONTEXT: Pegvisomant (PEG) therapy has been associated with drug-induced liver dysfunction in acromegalic patients. The mechanism of its toxicity remains unknown. OBJECTIVE: The primary objective was to determine whether or not the UGT1A1*28 polymorphism associated with Gilbert's syndrome influences the development of liver dysfunction during PEG treatment. DESIGN AND SETTING: A cross-sectional study was conducted in four Spanish university hospitals. PATIENTS: Thirty-six acromegalic patients with active disease, resistant to somatostatin analogs, participated. RESULTS: The prevalence of the UGT1A1*28 homozygous and heterozygous genotypes in acromegalic patients was 14 and 44%, respectively. Ten patients (28%) developed liver function test (LFT) abnormalities. There was a tendency for more frequent liver function abnormalities in males (70% males vs. 30% females, P = 0.058). Carriers of the UGT1A1*28 polymorphism had a higher incidence of LFT abnormalities than the UGT1A1 wild type (43% carriers vs. 7% wild type, P = 0.024). This difference persisted when adjusted in an all-factors multiple regression analysis [coefficient of determination (R(2)) = 0.463; P = 0.008] for age, gender, alcohol consumption, and UGT1A1*28 polymorphism. A stepwise multivariate likelihood binary logistic regression analysis (R(2) = 0.40; P = 0.003) identified male gender (beta = 7.21; P = 0.033) and UGT1A1*28 polymorphism (beta = 14.1; P = 0.028) as the only significant predictors for the development of LFT abnormalities. CONCLUSIONS: The UGT1A1*28 genotype and male gender predict an increased incidence of LFT abnormalities during PEG therapy in acromegaly.

Gilbert's syndrome and hyperbilirubinemia in protease inhibitor therapy--an extended haplotype of genetic variants increases risk in indinavir treatment.

BACKGROUND/AIMS: Gilbert's syndrome is a frequent genetic conjugation abnormality associated with adverse drug effects. Genetic UDP glucuronosyltransferase (UGT)1A gene variants can influence gene transcription, inducibility and glucuronidation activity. Protease inhibitors used in human immunodeficiency virus (HIV) infection and chronic viral hepatitis can inhibit UGTs. Indinavir (IDV) can lead to hyperbilirubinemia in Gilbert's syndrome (UGT1A1*28), which does not explain interindividual severity differences and may thus involve additional UGT1A variants. METHODS: One hundred and twenty-five HIV patients receiving IDV and 427 healthy blood donors were genotyped for the presence of UGT1A1*28, UGT1A3 -66T/C, UGT1A7 -57T/G, UGT1A7(N129K/R131K) using Taqman 5' nuclease assays. RESULTS: Hyperbilirubinemia was observed in 42%. UGT1A1*28 frequencies did not differ between HIV patients and controls but were significantly higher in hyperbilirubinemic patients. The frequency of homozygous carriers of the 4 UGT1A marker haplotype increased with hyperbilirubinemia affecting all patients with bilirubin levels >85 micromol/l. CONCLUSIONS: In IDV treatment the risk of severe hyperbilirubinemia is associated with genetic variants of the UGT1A3 and UGT1A7 genes in addition to Gilbert's syndrome (UGT1A1*28). This haplotype is a useful predictor of protease inhibitor-induced side effects.

Pegvisomant-induced cholestatic hepatitis with jaundice in a patient with Gilbert's syndrome.

We report on a patient with active acromegaly and Gilbert's syndrome who developed severe hepatic dysfunction during pegvisomant (PEGv) monotherapy. She was partially resistant to all previous therapies, including long-acting somatostatin analogs and cabergoline. Five months after starting PEGv therapy, with an already normalized IGF1, she developed cholestatic liver dysfunction with jaundice. Liver or biliary diseases including biliary sludge, cholelithiasis or liver steatosis were excluded. A liver biopsy was in keeping with drug-induced liver injury. The discontinuation of PEGv was followed by full clinical and biochemical recovery in 6 weeks. PEGv therapy was not resumed. Apart from a minimal increase of bilirubin levels, no liver function test abnormalities were found during the 4-year follow-up period after the PEGv was discontinued. Drug-induced liver injury is the most serious systemic adverse event resulting from PEGv therapy. Since patients with mild and asymptomatic liver disease could be at a higher risk of PEGv-induced hepatotoxicity, frequent monitoring of hepatic enzymes should be required in these cases.

Successful treatment of severe unconjugated hyperbilirubinemia via induction of UGT1A1 by rifampicin.

We report two patients with uncommon Gilbert's syndrome with severe unconjugated hyperbilirubinemia which was reduced from 200 to 60-90 micromol/L by long-term administration of rifampicin. Hepatic induction of bilirubin-glucuronosyltransferase was suggested by increased relative amounts of conjugated serum bilirubin. This molecular mechanism was confirmed in primary cultures of human hepatocytes.