Identification of a novel splice variant in SEC23B gene in a patient with concomitant presence of congenital dyserythropoietic anemia II and Gilbert's syndrome

BACKGROUND

Congenital dyserythropoietic anemia Ⅱ (CDA Ⅱ) is a rare inherited disorder of defective erythropoiesis caused by SEC23B gene mutation. CDA Ⅱ is often misdiagnosed as a more common type of clinically related anemia, or it remains undiagnosed due to phenotypic variability caused by the coexistence of inherited liver diseases, including Gilbert's syndrome (GS) and hereditary hemochromatosis.

METHODS

We describe the case of a boy with genetically undetermined severe hemolytic anemia, hepatosplenomegaly, and gallstones whose diagnosis was achieved by targeted next generation sequencing.

RESULTS

Molecular analysis revealed a maternally inherited novel intronic variant and a paternally inherited missense variant, c.[994-3C > T];[1831C > T] in the SEC23B gene, confirming diagnosis of CDA Ⅱ. cDNA analysis verified that the splice acceptor site variant results in two mutant transcripts, one with an exon 9 skip and one in which exons 9 and 10 are deleted. SEC23B mRNA levels in the patient were lower than those in healthy controls. The patient was also homozygous for the UGT1A1*6 allele, consistent with GS.

CONCLUSION

Identification of the novel splice variant in this study further expands the spectrum of known SEC23B gene mutations. Molecular genetic approaches can lead to accurate diagnosis and management of CDA Ⅱ patients, particularly for those with GS coexisting.

Prolonged Jaundice in a Premature Breastfed Infant With Gilbert's Syndrome

INTRODUCTION

Neonatal jaundice and prematurity pose significant barriers to breastfeeding in the first days of life. There is limited literature exploring the relationship between prolonged jaundice in breastfed infants and Gilbert's (Meulengraght) syndrome. This case study describes the diagnostic and therapeutic challenges associated with Gilbert's syndrome in a late preterm breastfed infant born in Germany.

MAIN ISSUE

In this case report, an infant born to a primipara woman presented at 3 weeks postpartum to an International Board Certified Lactation Consultant. The initial assessment revealed a late preterm infant with inadequate weight gain and jaundice. The dyad received breastfeeding support and eventually achieved adequate weight gain; however, the infant's jaundice persisted.

MANAGEMENT

The consulting midwife suggested that the persistent jaundice was "breastmilk jaundice" and recommended temporarily interrupting breastfeeding. Due to a suspected family history of Gilbert's Syndrome, the dyad was referred, instead, to a pediatric gastroenterologist. Pathologic liver disease was excluded, and genetic testing confirmed Gilbert's Syndrome. At 6 months of age, the dyad was successfully breastfeeding and beginning complementary feeding.

CONCLUSION

Genetic testing for Gilbert's Syndrome should be considered for infants with prolonged jaundice and positive family history. Interruption or cessation of breastfeeding are not evidence-based recommendations, and current guidelines do not support these practices. Lactation professionals play a critical role in the management of breastfeeding for preterm infants with prolonged jaundice and should refer to specialists to rule out pathologic etiologies.

Unconjugated Hyperbilirubinemia in Acetaminophen-Related Acute Liver Failure

BACKGROUND In the absence of liver transplantation, the natural history of acetaminophen-induced liver failure is characterized by a progressive increase of liver function tests, including bilirubin mainly as its conjugated form. The presence of high levels of unconjugated bilirubin is more unusual; its etiology is unclear and its prognostic factor has been poorly investigated. CASE REPORT A 52-year-old man with a history of chronic analgesics, alcohol, and illicit drug abuse developed acute liver failure in relationship with the ingestion of largely supra-therapeutic doses of acetaminophen over the days preceding admission. The patient received the classical N-acetylcysteine treatment regimen for acetaminophen overdose. Clinical course was characterized by a progressive worsening of the neurological condition, evolving to grade IV encephalopathy. Coagulation disorders persisted, with factor V level <10%. He fulfilled the criteria for liver transplantation, but this option was rejected after a careful psychiatric evaluation. Laboratory investigations revealed a progressive increase in serum unconjugated bilirubin until his death. As evidence for hemolysis was lacking, acquired deficit in bilirubin glucuronidation appeared likely and diagnosis of Gilbert's syndrome was excluded. CONCLUSIONS After the exclusion of other causes of high unconjugated bilirubin levels, the progressive increase in unconjugated bilirubin can reflect a persistent defect in bilirubin conjugation in relationship with liver centrilobular injury, but the relationship with acetaminophen-glucuronidation is not known and there are insufficient data to affirm that the ratio unconjugated/conjugated bilirubin could be used as a prognostic factor.

Clinical and genetic definition of serum bilirubin levels for the diagnosis of Gilbert syndrome and hypobilirubinemia

BACKGROUND AND AIMS

Gilbert syndrome (GS) is genotypically predetermined by UGT1A1*28 homozygosity in Europeans and is phenotypically defined by hyperbilirubinemia using total bilirubin (TB) cutoff ≥1mg/dL (17 μmol/L). The prevalence of illnesses associated with GS and hypobilirubinemia has never been studied prospectively. As TB varies with UGT1A1*28 genotyping, sex, and age, we propose stratified definitions of TB reference intervals and report the prevalence of illnesses and adjusted 15 years survival.

METHODS

UK Biobank with apparently healthy liver participants (middle-aged, n=138,125) were analyzed after the exclusion of of nonhealthy individuals. The stratified TB was classified as GS when TB >90th centile; <10th centile indicated hypobilirubinemia, and between the 10th and 90th centile was normobilirubinemia. We compared the prevalence and survival rates of 54 illnesses using odds ratio (OR), logistic regression, and Cox models adjusted for confounders, and causality by Mendelian randomizations.

RESULTS

In women, we identified 10% (7,741/76,809) of GS versus 3.7% (2,819/76,809) using the historical cutoff of ≥1 mg/dL (P<0.0001). When GS and hypobilirubinemia participants were compared with normobilirubinemia, after adjustment and Mendelian randomizations, only cholelithiasis prevalence was significantly higher (OR=1.50; 95% CI [1.3-1.7], P=0.001) in men with GS compared with normobilirubinemia and in causal association with bilirubin (P=0.04). No adjusted survival was significantly associated with GS or hypobilirubinemia.

CONCLUSIONS

In middle-aged Europeans, the stratified TB demonstrates a careless GS underestimation in women when using the standard unisex 1 mg/dL cutoff. The prevalence of illnesses is different in GS and hypobilirubinemia as well as survivals before adjusting for confounding factors. With the exception of cholelithiasis in men, these differences were no more significant after adjustment and Mendelian randomization.

A Novel SPTA1 Mutation in a Patient with Hereditary Spherocytosis without a Family History and Coexisting Gilbert's Syndrome

Most patients with hereditary spherocytosis (HS) have a family history of disease, while those without such a history are difficult to diagnose. We herein report a case of HS with no family history harboring a novel heterozygous mutation of SPTA1, c.2161G>A (p.E721K), and a homozygous polymorphism of UGT1A1*6. In silico analyses suggested that the mutation might contribute to the pathogenesis of HS. The coexistence of HS and Gilbert's syndrome increases the risk of gallstones. Therefore, splenectomy, alone or in combination with cholecystectomy, is recommended. The determination of genetic diathesis provides useful information for the management of hemolytic anemia.

The Mutation Hotspots at UGT1A Locus May Be Associated with Gilbert's Syndrome Affecting the Taiwanese Population

Gilbert's syndrome is mainly diagnosed through genetic analysis and is primarily detected through a mutation in the promoter region of the UGT1A1 gene. However, most of the research has been conducted on Caucasian populations. In this study, we studied the Han population in Taiwan to investigate the possibility of other mutations that could cause Gilbert's syndrome. This study comprised a test group of 45 Taiwanese individuals with Gilbert's syndrome and 180 healthy Taiwanese individuals as a control group. We extracted DNA from the blood samples and then used Axiom Genome-Wide TWB 2.0 array plates for genotyping. Out of 302,771 single nucleotide polymorphisms (SNPs) from 225 subjects, we detected 57 SNPs with the most significant shift in allele frequency; 27 SNPs among them were located in the UGT1A region. Most of the detected SNPs highly correlated with each other and are located near the first exon of UGT1A1, UGT1A3, UGT1A6, and UGT1A7. We used these SNPs as an input for the machine learning algorithms and developed prediction models. Our study reveals a good association between the 27 SNPs detected and Gilbert's syndrome. Hence, this study provides a reference for diagnosing Gilbert's syndrome in the Taiwanese population in the future.

Dependence of blood biochemical parameters on various genotypes of the UGT1A1 gene associated with gilbert's syndrome

Diagnosis of Gilbert's syndrome is based on the detection of homozygous carriage of an additional TA-repeat in the promoter of the UGT1A1 gene, leading to a decrease in the activity of the UGT enzyme. No large studies have been done in the Russian Federation on the prevalence of carriage of Gilbert's syndrome, as well as the biochemical and molecular profile of such patients. The aim of the study is to evaluate biochemical and molecular genetic parameters in patients with Gilbert's syndrome in Russia. The study included 124 healthy volunteers (group 1) and 5650 patients with suspected Gilbert's syndrome (group 2). The number of TA-repeats of the promoter region of the UGT1A1 gene was determined by the method of fragment analysis for all participants. The following biochemical parameters were analyzed for 299 patients from group 2: the level of bilirubin and its fractions, AST, ALT, cholesterol and LDL. In group 1 the prevalence of genotype (TA)6/(TA)6 was 39,52%, (TA)6/(TA)7 - 53,23%, (TA)7/(TA)7 - 7,26%, no rare forms were found. In group 2 the prevalence of genotype (TA)6/(TA)6 was 6,04%, (TA)6/(TA)7 - 20,05%, (TA)7/(TA)7 - 73,7%, rare alleles - 0,2%. Rare alleles included (TA)5/(TA)6, (TA)5/(TA)7, (TA)6/(TA)8 and (TA)7/(TA)8, as well as a new genotype not described in the literature previously - (TA)7/(TA)9. When assessing the level of total bilirubin and its fractions, a difference was revealed between the genotype of Gilbert's syndrome (TA)7/(TA)7 and the reference genotype (TA)6/(TA)6, and between genotypes (TA)7/(TA)7 and (TA)6/(TA)7. A significant increase in total bilirubin was demonstrated in carriers of a larger number of TA-repeats. There was no significant difference in the concentration of ALT, AST, cholesterol or LDL between different genotypes.The number of TA-repeats of the UGT1A1 gene affects the increase of total bilirubin and its indirect fraction, including the cases of rare allelic variants (TA≤5, TA≥8), but not the activity of ALT and AST and the lipid profile.

Fluid-attenuated inversion-recovery MR imaging in schizophrenia-associated with idiopathic unconjugated hyperbilirubinemia (Gilbert's syndrome)

Background

Patients with schizophrenia show a significantly higher frequency of hyperbilirubinemia the patients suffering from other psychiatric disorders and the general healthy population. The objective of the current study was to determine whether patients with schizophrenia-associated idiopathic unconjugated hyperbilirubinemia (Gilbert's syndrome, GS) have specific changes in signal intensities on fluid-attenuated inversion-recovery (FLAIR) magnetic resonance (MR) images.

Methods

Axial 5-mm-thick FLAIR MR images from schizophrenia patients with GS (n = 18) and schizophrenia patients without GS (n = 18), all diagnosed according to DSM-IV criteria, were compared with age- and sex-matched non-psychiatric controls (n = 18). Signal intensities in the hippocampus, amygdala, caudate, putamen, thalamus, cingulate gyrus, and insula were graded relative to cortical signal intensity in the frontal lobe.

Results

Compared to both schizophrenia patients without GS and normal controls, the schizophrenia patients with GS showed significantly increased signal intensities in almost all regions studied.

Conclusion

Patients with schizophrenia-associated GS have specific changes of signal intensities on FLAIR MR images, suggesting that schizophrenia with GS produces changes in the fronto-temporal cortex, limbic system, and basal ganglia.

Crigler-Najjar Syndrome Type II Diagnosed in a Patient with Jaundice Since Birth

Crigler-Najjar syndrome type II is caused by mutations in the UGT1A1 gene resulting in severely reduced hepatic activity of UDP-glucoronyltransferase - an enzyme required to convert bilirubin into a more soluble form that can then be removed from the body. Absence or severe deficiency of this enzyme can lead to bilirubin accumulation in the body resulting in yellow skin and eyes (jaundice). The earliest signs of this disease can be apparent in the neonatal period. Patients with Crigglar-Najjar syndrome type II respond to phenobarbital therapy which decreases their chances of getting bilirubinemia by 60-70% in 3 weeks. A 17 years old boy presented with the complaint of gastroenteritis. On examination, he was jaundiced and his parents reported that it has been present since birth. He was admitted in the hospital with the differential diagnosis of Gilbert syndrome, but later it was found that the unconjugated bilirubin levels were higher than those required for Gilbert's criteria. We report, herein, an extremely rare case of Crigler-Najjar syndrome type II and how the patient responded to phenobarbital therapy. Periods of fasting, stress and any kind of illness can worsen unconjugated hyperbilirubinemia leading to complications like kernicterus, so higher levels of unconjugated bilirubin should be addressed immediately and the patient along with his/her family should be educated about this disease.

Genetic Testing in Liver Disease: What to Order, in Whom, and When

Genetic causes of liver disease lead to a wide range of presentations, from mildly abnormal liver tests to acute liver failure. This article discusses the indications for testing and what to test for hereditary hemochromatosis, progressive familial intrahepatic cholestasis, benign recurrent intrahepatic cholestasis, lysosomal acid lipase deficiency, Gilbert syndrome, alpha-1 antitrypsin deficiency, and Wilson disease.

[Repeated yellowing of the skin and sclera for 2 years]

A two-year-old girl was admitted due to repeated yellowing of the skin and sclera for 2 years and had no other specific symptoms or signs. The use of phenobarbital could relieve the symptoms of jaundice. Multiple examinations showed increased indirect bilirubin levels, and the results of aminotransferases and liver imaging were normal. There was no evidence of hemolysis. The analysis of UGT1A1 gene in her family found that this child had double homozygous mutation of c.211G>A(G71R) and c.1456T>G(Y486D), which had been reported as the pathogenic mutation for Gilbert syndrome. Her parents carried double heterozygous mutation of G71R and Y486D and had no symptom of jaundice. The child was diagnosed as having Gilbert syndrome. It is concluded that as for patients with unconjugated hyperbilirubinemia which cannot be explained by liver damage and hemolysis, their family history should be investigated in detail and gene analysis should be performed as early as possible, in order to identify congenital bilirubin metabolic disorders.

Unusual presentation of Gilbert disease with high levels of unconjugated bilirubin. Report of two cases

Gilbert's syndrome is a benign condition characterized by asymptomatic sporadic episodes of jaundice, due to a mild unconjugated hyperbilirubinemia caused by a deficiency in bilirubin glucoronidation. Under certain physiologic or pathologic events bilirubin level rises but according to literature it does not reach out more than 3 mg/dl. We report 2 cases of Gilbert's syndrome, genetically tested, which presented with bilirubin levels above 6 mg/dl without any trigger or coexisting condition. In conclusion, bilirubin levels higher than 6 mg/dL in Gilbert syndrome are rare, hemolytic and other metabolism diseases must be ruled out, and genetic testing may be necessary in some cases.

Interplay of co-inherited diseases can turn benign syndromes in a deadly combination: haemoglobinopathy and bilirubin transport disorder

We present a case about a 25-year-old male patient suffering from a rare genetic disorder called Mizuho haemoglobin. He was admitted to the Intensive Care Unit with acute liver and renal failure. During admission he also developed a cardiac tamponade twice. Finally he received a liver transplantation. Hereafter the patient stabilised and his liver and renal functions improved. His symptoms could not be explained solely by his known disease. After searching the literature, similarities between his symptoms and a rare complication of sickle cell disease were found. Molecular diagnostics showed that the patient also suffered from Gilbert's syndrome. Due to his chronic haemolysis, symptoms of this other disease were masked. This stresses the importance of always looking for other causes if symptoms or changes cannot be explained by a known rare disorder.

[Establishment of multiplex hybri-probe method--analysis using the polymorphism of UGT1A1 gene]

There are a number of methods for gene analysis of a point mutation and deletion/insertion of several nucleotides. In 2011, we reported an improved hybridization probe methods (Hybri-Probe method) that are highly sensitive and accurate, and excellent in cost and time effectiveness. Here, we have developed the Multiplex Hybri Probe method for several types of mutations or polymorphisms including the microsatellite polymorphisms, especially of palindromic sequence such as (TA)n and (GC)n. In addition, several mutations are analyzed at a time. In this research we focused on the three types of polymorphism on the Uridine diphosphate glucuronyltransferase (UGT) gene. Design of the probes for the detection of UGT1A1*6(211 G --> A G71R) and UGT1A1*27 (686 C --> A P229Q) was not difficult because the mutations were a single base substitution. However, UGT1A1*28 (A (TA)6TAA --> A (TA)7TAA) has tandem and palindromic sequence. Since the probes to detect the mutation in such sequence resulted in failure, we made several mismatches, i.e., TATATATATATA --> TATGTGTATATA. As a result, the probes designed for the three polymorphisms above did not overlap in the Tm and were separated by approximately 10 degree intervals between 63.2 degrees C and 37.5 degrees C. In this Multiplex Hybri-Probe method, the three kinds of probe are added tube into the PCR product in the same tube and followed by the measurement of the Tm using the LightCycler. Thus, it is very simple, and performed by one step for any mutation including the microsatellite polymorphisms, and it also has good cost performance and favorable time efficiency. It takes two hours including the running time of PCR for completion of the analysis. It may also be available to the detection of other gene abnormalities.

Gilbert syndrome

Gilbert syndrome is a common autosomal dominant hereditary condition with incomplete penetrance and characterized by intermittent unconjugated hyperbilirubinemia in the absence of hepatocellular disease or hemolysis. In patients with Gilbert syndrome, uridine diphosphate-glucuronyl transferase activity is reduced to 30% of the normal, resulting in indirect hyperbilirubinemia. In its typical form, hyperbilirubinemia is first noticed as intermittent mild jaundice in adolescence. However, Gilbert syndrome in combination with other prevailing conditions such as breast feeding, G-6-PD deficiency, thalassemia, spherocytosis, or cystic fibrosis may potentiate severe hyperbilirubinemia and/or cholelithiasis. It may also reduce plasma oxidation, and it may also affect drug metabolism. Although in general the diagnosis of the syndrome is one of exclusion, molecular genetic tests can now be performed when there is a diagnostic problem. The most common genotype of Gilbert syndrome is the homozygous polymorphism A(TA)7TAA in the promoter of the gene for UDP-glucuronosyltransferase 1A1 (UGT1A1), which is a TA insertion into the promoter designated UGT1A1*28. No specific management is necessary as Gilbert syndrome is a benign condition.

CONCLUSION

Gilbert genotype should be kept in the clinician's mind, at least as a contributor factor, in cases with unexplained indirect hyperbilirubinemia.

Severe jaundice in two children with Kawasaki disease: a possible association with Gilbert syndrome

Kawasaki disease is a systemic vasculitis, mainly encountered in children. It may affect any organ. Acute cholestasis and severe obstructive jaundice is an atypical manifestation of the disease. We herein present two children with Kawasaki disease and severe direct hypebilibirunemia who also were homozygous and heterozygous respectively for the (TA)(7) promoter polymorphism of Gilbert syndrome. Intravenous immunoglobulin was administered to both patients at the acute phase of the disease and the fever remitted within 24 hr following the immunoglobulin administration. Furthermore oral aspirin at a dose of 80-100 mg/kg/24 hr was also given. The first child did not develop any coronary ectasia or aneurysm, whereas dilation of the right coronary artery was identified in the second child, one month after the disease onset. We discuss the possible contribution of Gilbert syndrome to the development of jaundice in our patients.

Diagnosis and treatment difficulties in 18-year-old male patient with hereditary hemochromatosis, chronic hepatitis B, Gilbert syndrome and ulcerative colitis

Among possible causes of chronic hepatitis in adolescents most common are infections, autoimmune disorders and metabolic diseases. Thus, diagnostic procedures should be multidirectional. This study reports diagnosis and treatment difficulties in an 18-year-old male patient with hereditary hemochromatosis (HH), ulcerative colitis (UC), chronic hepatitis B (CHB) and Gilbert syndrome. The presented case illustrates problems in diagnostics related to the presence of numerous disease conditions in one patient. It should be taken into consideration that these diseases coexisting in one patient can mutually affect their symptoms creating specific diagnostic difficulties.

Hyperbilirubinemia and intermittent lower urinary tract dysfunction

OBJECTIVE

To examine the effect of hyperbilirubinemia on lower urinary tract function.

METHODS

The study was conducted on 29 patients with suspected Gilbert's syndrome (GS), and who were subjected to fasting test for diagnostic purpose. The uroflowmetric test was performed after 24 h of fasting and after 24 h of hypercaloric intake.

RESULTS

After a 24 h fasting period, when bilirubin in the serum was at its highest concentration, 31% of patients had abnormal uroflowmetric patterns. Patients with abnormal uroflowmetric patterns had higher conjugated bilirubin after 24 h fasting period than patients with normal pattern (p = 0.012). After a 24 h of hypercaloric intake, all 29 patients had a normal (bell-shaped) uroflowmetric pattern.

CONCLUSIONS

The results imply that hyperbilirubinemia might be a predisposing factor for intermittent lower urinary tract dysfunction in children.

Evaluation of tests for Gilbert's syndrome

The effect of caloric restriction (400 kcal for 24 hours) on serum total and unconjugated bilirubin was studied in 30 subjects with Gilbert's syndrome and in 22 patients with different liver diseases. The method could not completely differentiate between Gilbert's syndrome and liver disease, but an increase in unconjugated bilirubin of 15 micromol/l or more supports the former diagnosis. This limit gave a 100% specificity and a sensitivity for males of about 90% and for females of about 40%. I.v. nicotinic acid caused similar rises of unconjugated bilirubin as reduced caloric intake in eight subjects with Gilbert's syndrome, but most of the subjects preferred the latter test. Results from erythrocyte porphyrin determination in seven subjects with Gilbert's syndrome gave some support to the presence of dyserythropoiesis.

Hereditary spherocytosis coexisting with Gilbert's syndrome: a diagnostic dilemma

Haemolytic anaemia generally gives rise to only a modest elevation of serum bilirubin. Unconjugated hyperbilirubinaemia of an extreme degree should raise suspicion of additional factors, such as Gilbert's syndrome, hepatocellular dysfunction or renal failure. We present a 17-year-old boy with hereditary spherocytosis coexisting with Gilbert's syndrome.

[Main symptom jaundice--differential diagnosis at the bedside]

In jaundice, tissues are yellow in color because of an excessive deposition of bilirubin secondary to hyperbilirubinemia. Bilirubin is the physiological end-product of heme metabolism. Jaundice is one of the main symptoms of hepatobiliary disease. Besides that, it might occur in the setting of cardiac, hematologic or pancreatic disorders. The onset of jaundice varies from acute with severe impairment of general condition to chronic and not being noticed by the patient at all. In the first part of this review, the physiological and pathophysiological molecular mechanisms of heme and bile metabolism are described in detail on a scientific basis. The knowledge of the main principles of heme degradation, canalicular bile secretion and enterohepatic cycling of bile salts helps to understand, why clinicians differentiate between prehepatic (hemolytic), hepatocellular and obstructive jaundice. A detailed patient's history and a careful physical examination are essential for the clinical differential diagnosis of jaundice. In combination with routinely obtained lab results, it is often possible to find the right diagnosis already at the bedside. To demonstrate this, the second part of this review sets the focus on the analysis of three case reports from the clinical point of view. The differential diagnosis of jaundice is summarized in a table.

Gilbert’s syndrome in children: Our experience

Introduction: Gilbert?s syndrome represents the most frequent hereditary disorder of bilirubin metabolism. It occurs in 2-7% of subjects in general population, and is manifested by mild unconjugated hyperbilirubinaemia of benign nature. Objective. The study was conducted in order to analyse our experience related to the circumstances of disclosure, age at onset and sex distribution of Gilbert?s syndrome in children. Method. The diagnosis of Gilbert?s syndrome was based on the findings of mild unconjugated hyperbilirubinaemia in the absence of haemolysis and organic liver disease, as well as significant increase of bilirubin unconjugated fraction in serum after a 3-day hypocaloric diet (400 kcal/daily). Results. Of 58 subjects with Gilbert?s syndrome, there were 40 (68.97%) boys and 18 (31.03%) girls, indicating a 2.22 fold higher incidence of boys than girls. The age at diagnosis of the disorder was similar in boys and girls, and was 12.2-18 (X=14.71?1.55) years for boys and 10.5-16.4 (X=14.38?2.10) years for girls (p>0.05). Except for 3 girls aged below 12 years, in all other patients the diagnosis was made after that age; in 20, between age 12 and 14 years and in 14, between age 14 and 16 years, while in 10 patents, it was made at age between 16 and 18 years. In 20 (34.48%) subjects, hyperbilirubinaemia was disclosed on routine paediatric examination, in 19 (32.76%) when differentiating the cause of recurrent or acute abdominal pain, in 17 (29.3%) during febrile condition and in 2 during insufficient caloric intake. The values of unconjugated bilirubinaemia, both before a hypocaloric test and after a 3-day energy deprivation, were higher in boys than girls, but this difference was statistically significant only after the 3-day hypocaloric diet in age group between 16 and 18 years (p=0.038). Also, no significant difference was found in bilirubinaemia level between the different age groups either in boys or girls. Conclusion. According to our findings, in children, Gilbert?s syndrome is manifested only in puberty, and 2.22 times more often in boys than girls. It is most frequently revealed during a routine pediatric examination, as well as when investigating the cause of abdominal pain and fever. A significantly higher level of serum bilirubin in boys as related to girls is registered only after a hypocaloric diet in age group between 16 and 18 years. .

[Juvenile hyperbilirubinaemia and its early manifestation in adolescence]

Mild isolated unconjugated hyperbilirubinaemia is incidentally or purposefully attained finding in 4-8% of population. Adolescence is a typical age for detection of hypebilirubinaemia. In these patients a mutation in gene-promoter for uridin-diphospho-glucuronyl-transpherase A 1, which determines development of the benign Gilbert's syndrome, is present in most of the cases. Although homozygote formation of this mutation was described in 11-16% of general population, only in a part of them hyperbilirubinaemia is manifested. Beginning or continuation of hyperbilirubinaemia in adolescent age is linked probably with some other changes in the hepatocyte and factors which influence it. Among adolescents with hyperbilirubinaemia, risk factors that can induce a metabolic liver overload have to be considered. They include oligosymptomatic or asymptomatic EBV infection, drug and alcohol abuse, hormonal contraception etc. These conditions must be respected in the regimen of these adolescents.

Biochemical "liver function tests"

This article considers two common scenarios of “abnormal” liver test results that may be seen in primary care. It looks at the pitfalls in liver testing and summarises guidance, including further investigations that may or may not be warranted

A shortened, 2-hour rifampin test: a useful tool in Gilbert's syndrome

INTRODUCTION

Diagnosis of Gilbert's disease often involves unnecessary testing and patient anxiety. Rifampin test can support the diagnosis; it has been described in short series and lacks standardization in dose, collection times, result presentation and interpretation. Our objective was to compare the response to oral rifampin in a series of patients with Gilbert's disease, 2 and 4 h after drug administration.

PATIENTS AND METHODS

Eighty-nine patients with Gilbert's disease (elevated total bilirubin with no hepatopathy or hemolysis) were recruited. After a basal blood collection, 900 mg rifampin were administered per os and new samples were drawn 2 and 4 h later. Total and esterified bilirubin were measured in every sample. Haptoglobin concentration was also analyzed.

RESULTS

When expressed as relative increase with respect to basal values, variations observed 2 h after rifampin intake were all above 15%. A significant correlation (r = 0.902; p = 0.000) was found between relative increases 2 and 4 h after drug administration. No significant variations were found in haptoglobin concentrations.

CONCLUSION

Rifampin test is useful in diagnosing Gilbert's disease, but variations in total bilirubin concentrations (basal and post-rifampin) make that no absolute cut-off value can be used. Correlation between 2- and 4-h relative increases suggests that a shortened version could simplify the test.

[Gilbert's syndrome: a clinicogenetic trial]

AIM

To improve diagnosis of Gilbert's syndrome (GS) basing on functional and genetic methods of examination.

MATERIAL AND METHODS

GS was diagnosed in 88 patients aged 15-72 years using clinical and genetic tests.

RESULTS

Genotyping has detected changes in promotor part of the gene coding uridindiphosphateglucuroniltransferase. In homozygous carriers GS was characterized by a higher baseline level of bilirubin, distinct response to functional tests, frequent combination with essential tremor. In heterozygous patients GS often ran latently.

CONCLUSION

Four variants of GS course were established: dispepsic, asthenovegetative, jaundice, latent. Low-caloric diet followed by fenobarbital raised sensitivity and specificity of the test. A clinical classification of GS is proposed. The detected disorders of antipirin pharmacokinetics allow prognosis of the risk of unwanted reactions to the drugs metabolized by monooxigenases of the liver.

[Molecular diagnosis of heritable unconjugated hyperbilirubinemias]

There is considerable evidence suggesting that genetic damages to human uridine diphosphate glucuronyltransferase (UDPGT) gene located on clhromosome 2q37 are responsible for hereditary unconjugated hyperbilirubinemias (HUHB). The Crigler-Najjar syndrome of types I and II is characterized by structural mutations on one of 5 exons of HUHB gene, resulting in the synthesis of defective catalytically inactive isoforms of the enzyme. In Gilbert's syndrome, genetic alterations are located at the promoter of the gene and accompanied by the nucleotide insert of thymine adenine (TA). Promoter prolongation impairs the binding of IID transcription factor and leads to the decreased production of the enzyme UDPGT 1,1. Examination of the molecular epidemiology of gene mutations of UDPGT 1,1 that is typical of Gilbert's syndrome ascertained a great difference in the indices, from 2 to 16% in the Asian and European populations, respectively. In addition to polymerase chain reaction, high performance liquid chromatography may be used for the diagnosis of genetic alterations in Gilbert's syndrome.

Analysis of the UDP-glucuronosyltransferase gene in Portuguese patients with a clinical diagnosis of Gilbert and Crigler-Najjar syndromes

We describe the molecular study in a cohort of 120 Portuguese patients with the clinical diagnosis of Gilbert syndrome and in one with the diagnosis of Crigler-Najjar syndrome type II, as well as a prenatal diagnosis of Crigler-Najjar syndrome type I. Among the 120 unrelated patients with Gilbert syndrome, 110 were homozygous for the [TA]7 allele ([TA]7/[TA]7), and one patient was a compound heterozygote for two different insertions ([TA]7/[TA]8). The remaining 9 patients were heterozygous for the TA insertion ([TA]6/[TA]7). Additional studies in these 9 patients revealed heterozygosity for the c.674T>G, c.488_491dupACCT and c.923G>A mutations, in 1, 1 and 4 patients, respectively. The patient with Crigler-Najjar syndrome type II was a compound heterozygote for [TA]7 and the c.923G>A mutation. The undocumented polymorphisms c.-1126C>T and c.997-82T>C were also detected in the course of this study. Prenatal diagnosis in a family with a boy previously diagnosed as Crigler-Najjar syndrome type I and homozygosity for the c.923G>A mutation revealed that the fetus was unaffected. Homozygosity for the [TA] insertion was found to be the most frequent cause of GS in our population. Identification of further mutations in the UGT1A1 gene was also seen to contribute significantly towards diagnosis.

Role of overnight rifampin test in diagnosing Gilbert's syndrome

BACKGROUND

Gilbert's syndrome (GS) is the most common inherited disorder of bilirubin metabolism. Recent data show that the rifampin test can be used as a diagnostic test but there is controversy about its effect on bilirubin level in normal individuals. We studied the effect of administration of rifampin on serum bilirubin level in patients with GS and in healthy individuals.

METHODS

Serum total and unconjugated bilirubin levels were measured in 16 patients with GS and 15 healthy individuals before and after a single 600-mg oral dose of rifampin.

RESULTS

In patients with GS, mean (SD) serum total and unconjugated bilirubin level increased from 2.15 (0.49) and 1.56 (0.41) mg/dL, respectively to 3.23 (0.72) (p< 0.001) and 2.52 (0.71) mg/dL (p< 0.001), respectively after rifampin administration, and in healthy subjects from 0.69 (0.13) and 0.34 (0.09) mg/dL, respectively to 1.68 (0.56) (p< 0.001) and 0.84 (0.23) mg/dL (p< 0.001), respectively. Elevation of these levels above the normal cut-off levels had poor accuracy for the diagnosis of GS. However, elevation of total serum bilirubin after rifampin above 2.4 mg/dL was 93.8% sensitive and 93.3% specific for the diagnosis of GS, and elevation of unconjugated bilirubin above 1.3 mg/dL was 100% sensitive and 100% specific.

CONCLUSIONS

Rifampin elevates bilirubin level to above normal in GS and healthy subjects. Overnight rifampin test may be useful for the diagnosis of GS if cut-off levels for serum total and unconjugated bilirubin level of more than 2.4 and 1.3 mg/dL are used.

Gilbert's syndrome disclosed during the treatment of hematological malignancies

Gilbert's syndrome (GS) is a benign, familial condition characterized by recurrent asymptomatic non-hemolytic low-grade indirect hyper-bilirubinemia. Conditions related to fasting, stress or co-morbidity might reveal the disease in asymptomatic individuals. Seven patients who were treated for a hematological malignancy were identified with reversible indirect hyper-bilirubinemia. Liver function tests in all of them, including bilirubin levels were normal before the therapeutic maneuver, which was the delivery of combined chemotherapy in three cases and a bone marrow transplantation in four (three allografts and one autograft). Bilirubin levels returned to normal in all five patients following treatment. GS should not be overlooked in individuals exposed to these treatments who develop hyperbilirubinemia and jaundice.

Unconjugated hyperbilirubinemia in nonalcoholic steatohepatitis--is it Gilbert's syndrome?

BACKGROUND

Patients with nonalcoholic steatohepatitis (NASH) have normal liver function tests except for raised transaminases until they have progressed to cirrhosis of liver. The objective of this study was to evaluate patients of NASH for the presence of hyperbilirubinemia at presentation.

METHOD

Sixty-seven patients of NASH were studied for the presence of hyperbilirubinemia at presentation. All patients were worked up for the presence of cirrhosis and hemolytic work up and fasting test were done in those found with unconjugated hyperbilirubinemia.

RESULTS

Five out of 67 patients (7.5%) of NASH were found to have unconjugated hyperbilirubinemia. Though the fasting test was not positive, they all had a negative hemolytic workup and none of them had underlying cirrhosis. Clinical characteristics of patients with unconjugated hyperbilirubinemia were similar to those with normal serum bilirubin levels.

CONCLUSION

Unconjugated hyperbilirubinemia in patients with NASH may suggest an associated Gilbert's syndrome.

Conjugated bilirubin measurements in Gilbert's syndrome: method dependence

BACKGROUND

Introducing new methodology often requires alteration to reference ranges and may cause inconvenience. Reagent suppliers may not have validated reference ranges quoted in their method sheets. When ratios of analytes are important, as for conjugated and unconjugated bilirubin, the combined changes can cause confusion.

METHODS

The effect on bilirubin result interpretation following a change from Vitros (E950) dry slide technology to the Bayer ADVIA 1650 wet chemistry system was studied.

RESULTS AND CONCLUSION

Over-estimation of conjugated bilirubin without an appropriate reference range can cause interpretative confusion. It is important to identify key patient groups likely to be affected by method changes well in advance. These need to be worked up in addition to reference range checks. It is unwise to rely on manufacturers for advice in this area. This report gives conjugated or direct bilirubin and total bilirubin values obtained using the above methods in nine patients with Gilbert's syndrome.

A new case of (TA)8 allele in the UGT1A1 gene promoter in a Caucasian girl with Gilbert syndrome

The authors describe a 5-year-old Caucasian girl, referred to their hospital for evaluation of an unconjugated hyperbilirubinemia (57.9 micromol/L) detected from blood analysis during an episode of fever. The molecular analysis of the TATA-box region of the UGT1A1 gene revealed that the patient was a compound heterozygote for two insertions, one TA and the other TATA [(TA)(7)/(TA)(8)]. This is the first case of (TA)8 allele found in a Portuguese Caucasian patient and the third found in the literature.

Importance of serum bile acids determination in adolescents with juvenile hyperbilirubinaemia

The aim of the study was to identify moderate liver impairment in a group of hyperbilirubinaemic adolescents. Using gas chromatography we assessed both total bile acid and primary bile acid levels in 50 adolescents with juvenile hyperbilirubinaemia. At the same time we performed hepatologic examinations and subsequent follow-up assessment of these patients for a period of at least 2 years. As a control group we examined 30 adolescents without any impairment of both the liver and gastrointestinal tract, and 18 patients with low grade (moderately) active chronic hepatitis. In both groups we assessed total and primary bile acids levels as well as conventional liver tests (bilirubin, ALT, AST). On the basis of the clinical course and laboratory findings we divided our patients with juvenile hyperbilirubinaemia into two groups: a group of individuals with Gilbert's syndrome (30 patients) and a group of individuals with probable moderate liver impairment (20 patients). The latter group consisted of the adolescents who exhibited bilirubinaemia over 90 micromol/l and/or exhibited hepatomegaly or splenomegaly proved by the ultrasound examination and/or exhibited intermittent elevation of the liver aminotransferases serum levels. In the group of individuals with moderate liver impairment serum total bile acid levels were significantly elevated in 26% of patients, and the serum cholic acid level was significantly elevated in 25% of patients. These two parameters mutually correlated at a high level of significance. Juvenile hyperbilirubinaemia is one of the common conditions of adolescent age. Its etiology is diverse; it includes both benign conditions like Gilbert's syndrome and post-hepatitic and toxic conditions that require a long-term regimen and follow-up examinations. The number of people suffering from juvenile hyperbilirubinaemia has been growing in the population. Currently 4-6% of the adolescent population suffers from this disease. This growing number is probably caused by external factors of our environment (infection, toxic effects). The determination of mild liver disease in hyperbilirubinaemic patients and the provision of an adequate regimen of exercise and adequate nutritional measures is of great importance for the health of the adolescent population.

[Gilbert's syndrome--myths and reality]

Gilbert's syndrome is defined as a hereditary, mild, chronic, unconjugated hyperbilirubinemia occurring in the absence of overt hemolysis or any other evidence of liver disease. It is caused by a mutation of the specific UDP glucuronosyl transferase conjugating bilirubin with glucuronic acid resulting in a reduced activity of this enzyme. Gilbert's syndrome is considered as a rather benign disorder without necessity of any therapeutic intervention. It is therefore crucial to establish a correct diagnosis and differentiate this syndrome from serious disorders of the liver tissue. In recent years strong antioxidant effects of bilirubin were demonstrated in numerous studies and the protective role of hyperbilirubinemia in the pathogenesis of various oxidative stress-mediated diseases was suggested. Gilbert's syndrome and its relationship to associated disorders such as hemolysis, pigment cholelithiasis, neonatal jaundice, schizophrenia and drug interactions are also being discussed.