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Pietro Vajro

Publications and source records attributed to Pietro Vajro.

15 recordsLinked to original sources

Seven novel mutations of the UGT1A1 gene in patients with unconjugated hyperbilirubinemia.

The aim of this study was to identify new pathogenic variations of the UGT1A1 gene in 11 patients diagnosed with neonatal unconjugated hyperbilirubinemia. We describe two cases in which clinically unapparent heterozygotic mutations in the UGT1A1 gene may become evident in combination with certain environmental conditions or additional genetic defects.

Crigler-Najjar Syndrome↗

The canine copper toxicosis gene MURR1 is not implicated in the pathogenesis of Wilson disease.

BACKGROUND: It has recently been demonstrated that the Wilson disease (WD) protein directly interacts with the human homolog of the MURR1 protein in vitro and in vivo, and that this interaction is specific for the copper transporter. The aim of the present study was to clarify the role of MURR1 in the pathogenesis of WD as well as in other WD-like disorders of hepatic copper metabolism of unknown origin. METHODS: Using the single-strand conformation polymorphism (SSCP) method followed by sequencing, we analyzed the 5' untranslated region (UTR) and three exons of the MURR1 gene in three groups of patients: 19 WD: patients in whom no mutations were detected in the ATP7B gene, 53 WD: patients in whom only one mutation in the ATP7B gene was found, and 34 patients in whom clinical and laboratory data suggested a WD-like disorder of hepatic copper metabolism of unknown origin. RESULTS: We detected in these patients six rare nucleotide substitutions, namely one splice-site consensus sequence and one missense and four silent nucleotide substitutions. All substitutions except one were found in the heterozygous state. No difference in the frequencies of the various substitutions was observed between patients and controls. CONCLUSIONS: These data suggest that the MURR1 gene and its protein product are unlikely to play a primary role in the pathogenesis of Wilson disease. More extensive studies with larger numbers of clinically homogeneous patients should be carried out to establish whether nucleotide alterations in the MURR1 gene may have a role in causing WD or WD-like disorders or act as modifying factors in the phenotype variability in WD.

Adaptor Proteins, Signal Transducing↗

Emotional and behavioral problems after pediatric liver transplantation: a quantitative assessment.

Several uncertainties regarding psychological problems in children who underwent liver transplantation and the need to differentiate these disturbances from those related to the underlying previous chronic liver disease itself exist. This background triggered the present pilot study to investigate, using quantitative assessment methods, the incidence and the type of emotional and behavioral disturbances after liver transplantation. Sixteen liver transplant recipients (aged 5.7-14.4 yr) and 12 age-matched controls with stable chronic liver disease were assessed through the parent report form of Child Behavior Checklist/ 4-18. The mean time elapsed since transplantation was 8.1 yr. No patient or family had received psychological support during chronic liver disease or at any phase of the transplantation process. Transplanted children scored within borderline range for Internalizing and Total Behavioral Problems and within pathological range for Competences, except for the Activity Scale. Transplanted children showed more Total Behavioral (p = 0.005) and Externalizing Problems (p = 0.0005) than controls. Both groups scored within the pathological range for Total Competences with no significant differences between the two groups. Our findings suggest that in the absence of support programs a psychological risk does exist for a long period of time, after transplantation. Regarding Total Behavioral Problems and Externalizing Problems, this risk is higher than in children with chronic liver disease.

Adolescent↗

Cryptogenic liver disease in four children: a novel congenital disorder of glycosylation.

We investigated the metabolic defect(s) of four children who presented with isolated cryptogenic chronic liver disease, coagulopathy, and abnormalities of several unrelated serum glycoproteins. Analysis of the patients' serum glycoproteins and fibroblasts suggest they have a novel congenital disorder of glycosylation (CDG). All had abnormal transferrin (Tf) isoelectric focusing (IEF) profiles. More detailed analysis of Tf by electrospray ionization mass spectrometry (ESI-MS) showed a plethora of abnormal glycosylations that included loss of 1-2 sialic acids and 1-2 galactose units, typical of Group II defects. Tf from two patients also lacked 1-2 entire oligosaccharide chains, typical of Group One disorders. Total serum N-glycans were analyzed by HPLC and matrix-assisted laser desorption/ionization mass spectrometry and also showed increased proportion of neutral glycan chains lacking sialic acids and galactose units. Analysis of patient fibroblasts eliminated CDG-Ia, through CDG-Ih, -IL and CDG-IId. Our results suggest that a subset of children with clinically asymptomatic, cryptogenic hypertransaminasemia and/or liver steato-fibrosis may represent a novel type of CDG-X with an unknown defect(s). Clinicians are encouraged to test such patients for abnormal Tf glycosylation by ESI-MS.

Child, Preschool↗

Characterization of liver involvement in defects of cholesterol biosynthesis: long-term follow-up and review.

Inborn defects of cholesterol biosynthesis are a group of metabolic disorders presenting with mental retardation and multiple congenital anomalies (MCA/MR syndromes). Functional and structural liver involvement has been reported as a rare (2.5-6%) complication of the Smith-Lemli-Opitz syndrome (SLOS) and it has not been fully characterized. Here, we report on a long-term follow-up study of four patients with SLOS, and one case with lathosterolosis who presented with liver disease and underwent an extensive diagnostic work-up. Reports of liver involvement in cholesterol biosynthesis defects are reviewed. Two main different patterns of liver involvement emerged: progressive cholestasis, and stable isolated hypertransaminasemia. In our series, the first pattern was found in two patients with SLOS and one with lathosterolosis, and the second in two SLOS cases. Cholestasis was associated with early lethality and normal serum gamma-glutamyl-transferase (GGT) levels in SLOS, while possible prolonged survival and high GGT levels were seen in lathosterolosis. Hepatic fibrosis was present in both conditions. Liver biopsy performed in one of our SLOS patients with isolated hypertransaminasemia, showed only mild hydropic degeneration of the hepatocytes. The presence of liver involvement in 16% of the SLOS patients diagnosed at our Center suggests that this complication might have been underestimated in previously reported cases, possibly overshadowed by the severity of multiple malformations. Fetal hepatopathy, cholestasis, and isolated hypertransaminasemia can occur also in other disorders of cholesterol biosynthesis, such as mevalonic aciduria, desmosterolosis, Conradi-Hunermann syndrome, Greenberg dysplasia, and Pelger-Huet homozygosity syndrome. This group of inherited disorders should be considered in the differential diagnosis of patients presenting with liver disease associated with developmental delay and/or multiple malformations. Periodic liver function evaluations are recommended in these patients.

Child↗

Spectrum of UGT1A1 mutations in Crigler-Najjar (CN) syndrome patients: identification of twelve novel alleles and genotype-phenotype correlation.

Crigler-Najjar syndrome types I and II (CN1 and CN2) are usually inherited as autosomal recessive conditions and are characterized by non-hemolytic unconjugated hyperbilirubinaemia. CN1 is the most severe form, associated with the absence of hepatic bilirubin-uridinediphosphoglucuronate glucuronosyltransferase (UGT1A1) activity. CN2 presents intermediate levels of hyperbilirubinaemia as a result of an incomplete deficiency of hepatic UGT1A1 activity. Here, we present the analysis of UGT1A1 gene in 31 unrelated Crigler-Najjar (CN) syndrome patients. This analysis allowed us to identify 22 mutations, 12 of which were not previously described, expanding the spectrum of known UGT1 mutations to 77. Novel mutations, considered pathogenic, including one nonsense mutation, two altered splice sites, one single base deletion and nine missense mutations were identified in coding exons of the UGT1A1gene and flanking introns. Several novel missense mutations localize in critical domain of UGT1A1 enzyme. In addition, the evaluation of Gilbert-type promoter of UGT1A1in Crigler-Najjar (CN) syndrome patients was performed. The polymorphisms of the promoter region can modify the UGT1A1 mutation phenotype. This study represents the molecular characterization of the largest cohort of Italian Crigler-Najjar Gilbert syndrome patients studied so far; increase the mutational spectrum of UGT1A1 allelic variants worldwide and provide a new insight useful for clinical diagnosis and genetic counseling.

Alleles↗

Metabolic, hormonal, oxidative, and inflammatory factors in pediatric obesity-related liver disease.

OBJECTIVE: To examine the role of metabolic, hormonal, oxidative, and inflammatory factors in pediatric obesity-related liver disease. STUDY DESIGN: In 50 obese children (age 7 to 14 years) with (n = 20, group 1) or without (n = 30, group 2) hypertransaminasemia and ultrasonographic liver brightness, we studied insulin resistance (fasting glucose/insulin ratio [FGIR]) and serum levels of leptin, iron, transferrin, ferritin, C-reactive protein (CRP), white blood cell (WBC) count, tumor necrosis factor (TNF)-alpha, interleukin (IL)-6, C282Y and H63D mutations, and erythrocytic glutathione peroxidase (GPX) activity. RESULTS: FGIR (6.7 +/- 4.1 vs 9.2 +/- 5.2; P = .02), serum ferritin (88.8 +/- 36.0 vs 39.9 +/- 24.0 ng/mL; P = .0001), serum CRP (5.4 +/- 6.0 vs 1.1 +/- 1.6 mg/dL; P = 0.004), and GPX (8.4 +/- 0.9 vs 5.0 +/- 0.5 U/g Hb; P = .05) were significantly higher and more frequently deranged in group 1 than in group 2. FGIR, ferritin, and CRP values were simultaneously deranged in 41% of the group 1 patients and in none of the group 2 patients ( P = .098). Serum leptin, iron, and transferrin, WBC, TNF-alpha, IL-6, and C282Y and H63D mutations were similar in the 2 groups. CONCLUSIONS: Insulin resistance, oxidative stress, and low-grade systemic inflammatory status are implicated in pediatric obesity-related liver disease. These findings may be useful in planning pathophysiologically based therapeutic trials for hepatopathic obese children who are unable to follow hypocaloric diets.

Adolescent↗

Features and outcome of autoimmune hepatitis type 2 presenting with isolated positivity for anti-liver cytosol antibody.

BACKGROUND AND AIMS: Autoimmune hepatitis (AIH) type 2 is identified by the presence in the serum of anti-liver/kidney microsome type 1 autoantibody. Anti-liver cytosol autoantibody has been reported in children with autoimmune liver disorders mostly in association with anti-liver/kidney microsome reactivity. However, its role as a sole marker of AIH type 2 is debated. We describe here a series of 18 children and adolescents (15 girls, 3 boys) with AIH with serum anti-liver cytosol type 1 (aLC1) as the only autoimmune marker. METHODS: A retrospective review was conducted from 3 pediatric hepatology units of all children with an autoimmune liver disease associated with aLC1 as found by immunofluorescence and/or immunodiffusion or immunoblotting. RESULTS: Age at first symptoms ranged from 11 months to 14 years; 12 children presented with acute hepatitis, 1 with progressive jaundice, and 5 were asymptomatic. Anti-liver/kidney microsome, antimitochondria, and anti-actin autoantibodies were not detected. Signs of cirrhosis were present in 11 children. Immunosuppressive treatment was effective in all except 2 children who had subfulminant hepatic failure and who required liver transplantation. Sixteen patients (14 with their native liver) currently are alive; 14 patients still are on immunosuppressive therapy after 1 to 22 years. According to the international scoring system for the diagnosis of AIH, 16 patients corresponded to a definite diagnosis and 2 corresponded to a probable diagnosis. CONCLUSIONS: The presence of aLC1 in children with acute or chronic liver disease of unknown origin strongly supports a diagnosis of AIH and is an indication for early immunosuppressive therapy.

Adolescent↗

Vitamin E treatment in pediatric obesity-related liver disease: a randomized study.

OBJECTIVE: A beneficial role of antioxidants in hepatopathic obese individuals has hitherto been inferred only from uncontrolled pilot studies. The authors compared the effect of vitamin E and weight loss on transaminase values and on ultrasonographic bright liver in a controlled group of children with obesity-related liver dysfunction. METHODS: Twenty-eight children with obesity-related hypertransaminasemia and bright liver were randomly allocated to two single-blind groups: group 1 (n = 14) treated with a low-calorie diet associated with oral placebo for 5 months, and group 2 (n = 14) treated with a low-calorie diet associated with oral vitamin E (400 mg/d x 2 months, 100 mg/d x 3 months). Transaminase values and ultrasonographic liver brightness along with weight loss and vitamin E levels were monitored. RESULTS: Variations in transaminase levels and percentage of patients with normalized transaminase values were comparable in the two groups. The disappearance of bright liver was observed only in patients who lost weight and was twice as common in patients from group 1. Two subgroups of patients with complete normalization of transaminase values emerged as a consequence of controlled adherence to diet alone (n = 6; significant decrease of percent overweight: P = 0.0019 ) and to vitamin E alone (n = 7; unmodified percent overweight and significant increase of vitamin E/cholesterol ratio: P < 0.0001). Changes in treatment-induced alanine aminotransferase levels in these two subgroups were comparable at month 2, whereas values at month 5 were significantly lower in the subgroup adherent to diet alone (P = 0.04). In the subgroup adherent to vitamin E alone, after 2 months washout, transaminase remained stable in 5 patients and increased in 2; bright liver persisted in all. CONCLUSIONS: Oral vitamin E warrants consideration in obesity-related liver dysfunction for children unable to adhere to low-calorie diets.

Alanine Transaminase↗

Serum transaminases in children with Wilson's disease.

OBJECTIVES: The response of serum transaminase levels to penicillamine and zinc treatment in Wilson's disease is poorly understood. The aim of this multicenter retrospective study was to evaluate transaminase levels after penicillamine and zinc treatment in children with Wilson's disease. PATIENTS AND METHODS: One hundred and nine patients with Wilson's disease (median age at diagnosis, 7.2 years; range, 1 to 18 years), treated for at least 12 months and observed in the last 20 years at 11 Paediatric Departments were studied. Clinical, laboratory and histologic features at diagnosis and initial treatment were recorded. Efficacy parameters were normalization of serum transaminase level and improved clinical and/or laboratory signs. One hundred and two patients had clinical or laboratory signs of liver disease. RESULTS: Fifty-six of 87 patients (64%) given penicillamine normalized serum alanine aminotransferase (ALT) levels within a median of 17 months (range, 2 to 96 months). Of the 29 patients with persistent hyper-ALT, 17 (59%) switched to zinc; only four of these normalized ALT on zinc within a median period of 38 months (range, 7 to 48 months). Eleven (50%) of the 22 patients given zinc alone normalized ALT within a median period of 6 months (range, 1 to 36 months). Of the 11 patients with persistent hyper-ALT, five switched to penicillamine. Three of the five normalized ALT within a median period of 6 months (range, 6 to 9 months). Overall, in penicillamine-treated and zinc-treated patients with persistent hypertransaminasemia, ALT decreased from a basal median of 236 IU/L (range, 54 to 640 IU/L) to a median of 78 (range, 46 to 960 IU/L) at the end of follow-up (P = 0.0245). Poor compliance was suspected in only 10% of cases. No predictive factor of persistent hypertransaminasemia was identified. Liver disease did not worsen in any patient during the study. CONCLUSIONS: Although the efficacy of penicillamine and zinc is well documented, it is notable that a subset of children with Wilson's disease-related liver disease (36%) had hypertransaminasemia despite appropriate treatment with penicillamine or zinc.

Adolescent↗

Per-rectal portal scintigraphy is complementary to ultrasonography and endoscopy in the assessment of portal hypertension in children with chronic cholestasis.

UNLABELLED: We evaluated the clinical usefulness of 99mTc-pertechnetate per-rectal portal scintigraphy (PPS) in the assessment of portal circulation in children with chronic cholestasis. METHODS: PPS percentage shunt index (%SI) (the amount of radionuclide that shunts the liver and reaches the systemic blood after injection in the rectum) was measured in 22 children (mean age, 7.2 +/- 4.9 y) and compared with established clinical, laboratory, and endoscopic and imaging parameters of portal hypertension (PH). Fourteen children had surgically treated biliary atresia, and 8 had chronic intrahepatic cholestasis. Six clinically well children served as control subjects. RESULTS: The %SI was 14.3 +/- 3.1 and 34.7 +/- 18.8 in controls and in patients, respectively (P < 0.01). A cutoff of 19% correctly allocated 100% of controls and 86% of patients. Mean %SI values were significantly higher in patients with biliary atresia, a high risk of pretransplantation death, esophageal varices (EV) at endoscopy, and an abnormal value for the ratio of lesser omentum thickness to abdominal aorta diameter (LO/Ao) at ultrasonography. Correlations between %SI values and several ultrasonographic continuous variables were statistically significant only for LO/Ao ratios (r = 0.51; P = 0.005) and spleen longitudinal diameters (r = 0.53; P = 0.01). The presence of EV could correctly be predicted only when values of %SI were greater than 30% (100% specificity; 56% sensitivity). Endoscopic and PPS findings agreed for a diagnosis of PH with EV in 3 of 7 patients with normal or borderline ultrasonographic LO/Ao ratios. PPS patterns and %SI values became normal in 3 children who underwent liver transplantation. CONCLUSION: In children with chronic cholestasis, PPS may be an advantageous, minimally invasive tool complementary to ultrasonography and endoscopy for better assessment and follow-up of PH before and after liver transplantation.

Adolescent↗

Noninvasive investigation of hepatopulmonary syndrome in children and adolescents with chronic cholestasis.

Early detection of hepatopulmonary syndrome (HPS) may be delayed because of invasiveness of the diagnostic procedures. In this pilot study, we prospectively investigated the usefulness of determining transcutaneous O(2) tension after 100% O(2) (TcPO(2)100) breathing using a transcutaneous hyperoxia test (THT) in 11 children with chronic cholestasis and without primary cardiopulmonary disease. These patients also underwent alveolar-arterial O(2) gradient testing (AaDO(2)) at an inspired oxygen fraction (FiO(2)) of 0.21, lung scintiscan, and contrast transthoracic echocardiography (TTE). Three of them had a liver transplantation because of the downhill course of their liver disease and respiratory status. THT transcutaneous O(2) tension at 21% FiO(2) (TcPO(2)21) was 75 +/- 13 mm Hg, and increased to 488 +/- 106 mmHg after 100% O(2) breathing (TcPO(2)100). Both mean values were not significantly different from those found in 8 age-matched controls (P = 0.9 and P = 0.5, respectively). However, one patient, in spite of her stable liver function, showed an abnormal TcPO(2)21 and TcPO(2)100 (45 mmHg and 210 mmHg, respectively). This same subject was also the only patient with abnormalities of AaDO(2) (54.2 mm Hg; normal value, < 20 mm Hg), lung scintiscan (brain/lung ratio of technetium-99 fixation (B/L SI) = 9, normal value < 1), and TTE, suggesting intrapulmonary vasodilatations and shunts. Given the clinical development of cyanosis and platypnea, all criteria for HPS were fulfilled, and timing of her liver transplantation was therefore accelerated. This resulted in HPS regression. In children with chronic cholestasis, repeated transcutaneous bedside measurements are a rapid and reliable noninvasive test for characterizing the severity of abnormal oxygenation, and may prove useful also in liver posttransplantation monitoring.

Adolescent↗