Co-inherited Gilbert's syndrome: a factor determining hyperbilirubinemia in homozygous beta-thalassemia. (33/8398)

BACKGROUND AND OBJECTIVE: Patients with thalassemia major and intermedia show a marked variability of serum indirect bilirubin levels. In this paper we tested the hypothesis related to the variability of the glucuronidation bilirubin rate which depends on the configuration of the A(TA)nTAA motif of the UGT1*1 glucuronosyltransferase gene promoter. DESIGN AND METHODS: We studied the configuration of the A(TA)nTAA motif in 26 patients with thalassemia major and 34 with thalassemia intermedia. RESULTS: In patients with thalassemia major and in those with thalassemia intermedia significantly higher bilirubin levels were found in patients with the (TA)7/(TA)7 genotype, than in those with the (TA)7/(TA)6 or (TA)6/(TA)6 genotype. INTERPRETATION AND CONCLUSIONS: These results indicate that the (TA)7/(TA)7 genotype, the configuration found in patients with Gilbert's syndrome, is capable of modifying the clinical phenotype of homozygous beta-thalassemia. This is an example of the role played by co-inherited modifying gene(s) on the extent of clinical heterogeneity of monogenic disorders.  (+info)

(TA)8 allele in the UGT1A1 gene promoter of a Caucasian with Gilbert's syndrome. (34/8398)

BACKGROUND AND OBJECTIVE: Gilbert's syndrome, a chronic non-hemolytic unconjugated hyperbilirubinemia, is caused by a reduction in the activity of hepatic bilirubin UDP-glucuronosyltransferase (UGT1A1). This reduction has been shown to be due to a polymorphism in the promoter region of the UGT1A1 gene. The presence of seven thymine adenine (TA) repeats reduces the efficiency of transcription of the UGT1A1 gene. To elucidate the genetic background of a patient affected by Gilbert's syndrome, we collected blood samples from family members for the analysis of the A(TA)nTAA motif in the promoter region of the UGT1A1 gene. DESIGN AND METHODS: Analysis of the A(TA)nTAA motif in the promoter region of the UGT1A1 gene was performed by PCR. Estimation of UGT1A1 promoter containing the variable (TA) repeats was performed by using a luciferase reporter system. RESULTS: Three different genotypes were identified due to the presence of (TA)6, (TA)7 and (TA)8 repeats. The production of luciferase decreases in inverse relation to the number of repeats. INTERPRETATION AND CONCLUSIONS: The (TA)7 polymorphism, associated with Gilbert syndrome, is the only allele found up to now in white populations, while two other variants (TA)5 and (TA)8 have been identified in black populations. We describe here the first case of a subject affected by Gilbert's syndrome who is heterozygous for the (TA)8 allele in the promoter region of the UGT1A1 gene. This polymorphism, as well as the (TA)7 one, is associated with an increased level of bilirubin and a significant reduction of transcription activity of the UGT1A1 gene.  (+info)

Molecular pathology of Crigler-Najjar type I and II and Gilbert's syndromes. (35/8398)

BACKGROUND AND OBJECTIVE: Crigler-Najjar syndromes type I and II and Gilbert's syndrome are familial unconjugated hyperbilirubinemias caused by genetic lesions involving a single complex locus encoding for bilirubin-UDP-glucuronosyltransferase which is involved in the detoxification of bilirubin by conjugation with glucuronic acid. Over the last few years a number of different mutations affecting this gene have been characterized. The aim of this work is to review the molecular pathology of Crigler-Najjar and Gilbert's syndromes, to discuss its impact on the clinical and genetic classification of these conditions, and on the diagnostic evaluation of clinical pictures associated with unconjugated hyperbilirubinemia. EVIDENCE AND INFORMATION SOURCES: The authors of the present review are involved in the clinical management of patients with familial unconjugated hyperbilirubinemia as well as in the characterization of its molecular bases. Evidence from journal articles covered by the Science Citation Index and Medline has been reviewed and collated with personal data and experience. STATE OF THE ART AND PERSPECTIVES: It has been known for many years that mild to severe deficiency of bilirubin UDP-glucuronosyltransferase in the liver is the cause of two types of familial unconjugated hyperbilirubinemia, Crigler-Najjar syndromes I and II, and Gilbert's syndrome. Since the characterization of the gene encoding for bilirubin UDP-glucuronosyltransferase, a number of mutations affecting the expression of this gene have been identified. These mutations can be classified into three groups: mutations which result in a reduced production of a normal enzyme; mutations which give rise to the synthesis of a structurally abnormal and dysfunctional enzyme; mutations which completely abolish the expression of the affected allele. The combination of mutations affecting the coding region of the gene and of promoter mutations which reduce the expression of the gene accounts for the wide clinical spectrum of familial unconjugated hyperbilirubinemias, ranging from the clinically negligible Gilbert's syndrome to the severe and often fatal Crigler-Najjar type I syndrome. A better understanding of the genetics of these conditions and the availability of molecular diagnosis will improve the diagnostic efficiency and afford better informed genetic counseling, not only for Crigler-Najjar and Gilbert's syndromes, but also for several acquired conditions characterized by unconjugated hyperbilirubinemia.  (+info)

First identification of infectious salmon anaemia virus in North America with haemorrhagic kidney syndrome. (36/8398)

Haemorrhagic kidney syndrome (HKS), a serious disease affecting Atlantic salmon on the east coast of Canada, was determined to be caused by infectious salmon anaemia virus (ISAV) through the isolation of the pathogen on the SHK-1 (salmon head kidney) cell line and confirmation by ISAV-specific immunofluorescent antibody test (IFAT) and reverse transcriptase polymerase chain reaction (RT-PCR). In addition, the defining histopathology of HKS could be reproduced following the injection of material that rendered challenged fish ISAV-positive by cell culture in the absence of any other detectable pathogen. Preliminary nucleotide sequence comparison does not suggest any direct epidemiological connection between the Canadian and Norwegian isolates.  (+info)

Novel mutations in Rsk-2, the gene for Coffin-Lowry syndrome (CLS). (37/8398)

Coffin-Lowry syndrome (CLS) is an X-linked disorder characterized by facial dysmorphism, digit abnormalities and severe psychomotor retardation. CLS had previously been mapped to Xp22.2. Recently, mutations in the ribosomal S6 kinase (Rsk-2) gene were shown to be associated with CLS. We have tested five unrelated individuals with CLS for mutations in nine exons of Rsk-2 using Single Strand Conformation Polymorphism (SSCP) analysis. Two patients had the same missense mutation (C340T), which causes an arginine to tryptophan change (R114W). This mutation falls just outside the N-terminal ATP-binding site in a highly conserved region of the protein and may lead to structural changes since tryptophan has an aromatic side chain whereas arginine is a 5 carbon basic amino acid. The third patient also had a missense mutation (G2186A) resulting in an arginine to glutamine change (R729Q). The fourth patient had a 2bp deletion (AG) of bases 451 and 452. This creates a frameshift that results in a stop codon 25 amino acids downstream, thereby producing a truncated protein. This deletion also falls within the highly conserved amino-catalytic domain of the protein. The fifth patient has a nonsense mutation (C2065T) which results in a premature stop codon, thereby producing a truncated protein. These mutations further confirm Rsk-2 as the gene involved in CLS and may help in understanding the structure and function of the protein.  (+info)

Treatment with the antibiotic roxithromycin in patients with acute non-Q-wave coronary syndromes. The final report of the ROXIS Study. (38/8398)

AIMS: Mounting evidence suggests infection, specifically Chlamydia pneumoniae, plays a role in atherosclerosis. We tested whether antibiotic treatment with the macrolide roxithromycin improves clinical outcome in patients with acute non-Q-wave coronary syndromes. Preliminary reports revealed a reduction in events in the roxithromycin group at 30 days. We now report the long-term follow-up results. METHODS AND RESULTS: Sixty-four per cent of the initial 202 patients with unstable angina who were randomly assigned to receive either roxithromycin or placebo for 30 days completed the active treatment period. At day 30, the primary triple and double end-point rates were 9% and 4% in the placebo group compared to 2% and 0% in the roxithromycin group (unadjusted P = 0.032 and 0.058, respectively). The secondary triple and double end-point rates were again higher in the placebo group at day 90 (12.5% and 6.25% vs 4.37% and 0%, unadjusted P = 0.065 and 0.029, respectively), and at day 180 (14.6% and 7.29% vs 8.69% and 2.17%, unadjusted P = 0.259 and 0.17, respectively). Anti-C, pneumoniae IgG titres were unchanged in both groups while C-reactive protein levels decreased in both strategies, with a more significant decrease in the roxithromycin arm (P = 0.03). Elevated C-reactive protein levels predicted the need for revascularization. CONCLUSIONS: In this pilot trial, roxithromycin appears to extend the clinical benefit of preventing death and re-infarction for at least 6 months after initial treatment.  (+info)

Bilateral basal ganglial necrosis after allogeneic bone marrow transplantation in a child with Kostmann syndrome. (39/8398)

A 6-year-old girl underwent allogeneic BMT from a matched sibling donor for the treatment of Kostmann syndrome. She suddenly became drowsy on day 30 after BMT, and lost consciousness 2 days later. Cranial CT scan showed symmetrical lesions suggesting bilateral necrosis in the basal ganglia. Clinical and laboratory investigations failed to reveal any evidence of neurometabolic disease.  (+info)

Cauda equina syndrome in ankylosing spondylitis: a report of six cases. (40/8398)

Six patients with ankylosing spondylitis and features of a cauda equina syndrome are described. The myelographic findings are discussed in relation to the pathogenesis of the disorder and its natural history. Present experience suggests that the cauda equina syndrome is a more common complication of ankylosing spondylitis than is usually thought.  (+info)