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Biomedical subjects

G Mieli-Vergani

Publications and source records attributed to G Mieli-Vergani.

At least 19 recordsLinked to original sources
PubMed2002

Serum hyaluronic acid concentrations are increased in cystic fibrosis patients with liver disease.

AIM: To determine whether serum hyaluronic acid (HA) concentrations are abnormal in patients with cystic fibrosis (CF) liver disease, and if so, whether the abnormality is associated with disease severity. METHODS: A total of 74 patients with CF were assessed for evidence of liver involvement as indicated by clinical, ultrasound, and biochemical findings. Serum hyaluronic acid concentrations were measured and compared with concentrations in 293 normal controls. Lung function in the CF patients was also recorded. RESULTS: Thirty four CF patients had no evidence of liver disease; in these, serum HA concentrations were similar to those in healthy controls (median (range): 16.1 (9.4-75.1) v 15 (1-77) microg/l). Nineteen CF patients had established liver disease detected by clinical and ultrasound examination, with significantly increased HA concentrations (56.1 (26-355) microg/l). Serum HA concentrations were also significantly increased, although to a lesser extent, in 21 CF patients with an abnormal liver ultrasound scan alone (22.4 (9.5-43.4) microg/l). There was no correlation between serum HA concentration and lung function. CONCLUSION: Serum HA concentrations were significantly increased in children with clinical or ultrasound evidence of liver disease, being higher in those with more advanced hepatic damage. Despite the inflammation and fibrosis present in CF lungs there was no correlation between HA concentration and lung function, suggesting that high concentrations were a failure of hepatic clearance rather than overproduction in the lung. Longitudinal measurement of HA concentrations may prove a useful marker for the development of significant liver damage in CF patients.

Biomarkers↗
PubMed2001

Hemodynamic response to continuous infusion of dobutamine in Alagille's syndrome.

BACKGROUND: Alagille's syndrome is a rare condition that is characterized by paucity of interlobular bile ducts and peripheral pulmonary artery stenosis. Liver transplantation in the setting of peripheral pulmonary stenosis and right ventricular hypertension seems to be associated with a higher mortality, which raises the concern that these patients are unable to increase their cardiac output in the immediate posttransplantation period to meet the demands of reperfusion and early graft dysfunction and cope with further increases in pulmonary vascular resistance. METHOD: Cardiac catheterization was performed in 15 children with Alagille's syndrome and peripheral pulmonary artery stenosis to measure the cardiac output response to dobutamine infusion. The cardiac output was measured before and during each increment of infusion of dobutamine at 10 microg/kg/min and 20 microg/kg/min by using a thermodilution catheter placed in the pulmonary artery. RESULTS: There was a significant change in the baseline cardiac index (P<0.001) with an infusion of 20 microg/kg/min of dobutamine with an increase from 4.4(1.0) L/min/m2 to 6.4(1.5) L/min/m2. There was, however, a wide variation between individuals in the increase in cardiac index, ranging from 7.3-95%. There was no correlation between the baseline systolic right ventricular/aortic pressure ratios and the increase in cardiac index (r=0.1086). CONCLUSION: The increase in cardiac index, in response to dobutamine in patients with Alagille's syndrome, is independent of the more conventional measurement of the right ventricular pressure. This method of producing a hemodynamic response is closer to the response that results after liver transplantation, and thus, it may be a better way of predicting the outcome of liver transplantation in these patients.

Adolescent↗
PubMed2001

Calcineurin-inhibitor related nephrotoxicity- reversibility in paediatric liver transplant recipients.

AIM: To study the efficacy of mycophenolate mofetil (MMF) as renal rescue in paediatric liver transplant recipients with calcineurin-inhibitor- (CI) related nephrotoxicity. METHODS: Pediatric liver transplant recipients with stable graft function and a glomerular filtration rate (GFR) <80 ml/min/1.73 m2 were enrolled. MMF was introduced at 20 mg/kg/day and increased to 40 mg/kg/day after 1 week. CI dose was then reduced 6 weeks to achieve blood levels 25% of baseline. GFR was reassessed after 6 and 12 months. RESULTS: Fourteen children with a median (range) interval from transplant of 57 (4-111) months were studied. Their median (range) GFR in ml/min/1.73 m2 increased from a baseline of 52 (31-71), to 69 (38-111) and 73 (35-98) at 6 and 12 months, respectively (P=0.00014). Side effects of MMF include leucopaenia in two and backache in one, two of whom discontinued MMF. Acute allograft rejection occurred in three children. All 14 are well with a median (range) follow-up of 24 (14-38) months from MMF introduction. CONCLUSION: MMF allows the recovery of renal function from CI related nephrotoxicity in more than 70% of paediatric liver transplant recipients with renal impairment.

Adolescent↗
PubMed2001

Veno-occlusive disease with multi-organ involvement following actinomycin-D.

Actinomycin-D (Act-D) is a rare cause of veno-occlusive disease (VOD). Between 1993 and 1998, we managed 6 patients, all male, median age 19 months (range 6-48 months) who received Act-D for Wilms' tumour (n=4), clear cell sarcoma (n=1) or rhabdomyosarcoma (n=1). VOD presented with a median platelet count of 12 x 10(9)/l, INR 3.8, fibrinogen 16 mg/l, fibrinogen degradation products (FDPs) > or =80 microg/l, aspartate aminotransferase (AST) 6922 IU/l, bilirubin 47 micromol/l. In 3 cases, transient liver dysfunction and thrombocytopenia without neutropenia had been observed after a previous course of Act-D. All six children developed encephalopathy, hepatomegaly, ascites, reversed portal flow and renal impairment. All received mechanical ventilation and two required haemofiltration. The treatment was supportive. Severe Adult Respiratory Distress Syndrome developed in 3 patients, all of whom died. 3 patients recovered. The outcome of VOD with multi-organ failure is poor. Intravascular coagulopathy precedes and characterises severe VOD during Act-D treatment.

Antibiotics, Antineoplastic↗
PubMed2001

Autoantibodies to human cytosol: a marker of sporadic porphyria cutanea tarda.

The enzymes potentially involved in the pathogenesis of sporadic porphyria cutanea tarda (PCT) reside in liver cytosoles and microsomes. PCT is frequently associated with hepatitis C virus (HCV) infection, which is in turn associated with autoimmune manifestations. To investigate whether autoimmune reactions, possibly triggered by HCV, are involved in the pathogenesis of PCT, we measured by immunoblot autoantibodies to human cytosolic and microsomal liver fractions in 82 patients with PCT (77% with HCV infection), 105 with other liver disorders and 40 healthy subjects. Anti-liver cytosolic antibodies were more frequent in PCT patients (38/82, 46%) than in pathological controls (P < 0.05-P < 0.001) or in healthy subjects (3/40, 8%, P < 0.001). Among PCT patients, anticytosolic antibodies were more frequent in HCV positive (36/63, 57%) than in HCV negative (2/19, 11%, P < 0.05) cases. Reactivity to a 40-kDa cytosolic polypeptide was present in 20 PCT patients (19 HCV positive), being more frequent than in all pathological controls (P < 0.01-P < 0.0001). Histological activity index (P = 0.04) and antibodies to HCV (P = 0.027) - but not HCV RNA - were associated independently with anticytosolic antibodies as assessed by multivariate analysis. In contrast, frequency of antiliver microsomal antibodies was similar in PCT patients (24/82, 29%) and pathological controls (8-26%), being higher in the autoimmune hepatitis control group (23/23, 100%, P < 0.0001). In conclusion, anticytosolic antibodies, particularly to a 40-kDa polypeptide, are frequent in PCT and associated with HCV infection and severity of liver damage.

Adult↗
PubMed2001

Sclerosing cholangitis in the paediatric patient.

Sclerosing cholangitis in childhood is a heterogeneous condition, which has different aetiologies. Sclerosing cholangitis may be inherited and diagnosed in the neonatal period (neonatal sclerosing cholangitis); it may present later with features of autoimmunity (autoimmune sclerosing cholangitis); or it may be associated with a variety of disorders, including Langerhans cell histiocytosis, immunodeficiency, psoriasis, cystic fibrosis, reticulum cell sarcoma and sickle cell anaemia. In contrast to the experience in adult patients, sclerosing cholangitis occurring as an individual disease (primary sclerosing cholangitis) is rare. The initiating events and possible pathogenic mechanisms differ in the various forms of sclerosing cholangitis and are still obscure. Treatment and prognosis depend on the type of sclerosing cholangitis present.

Adolescent↗
PubMed2001

Autoimmune hepatitis/sclerosing cholangitis overlap syndrome in childhood: a 16-year prospective study.

To investigate whether sclerosing cholangitis with an autoimmune serology characteristic of autoimmune hepatitis (AIH) and AIH are distinct entities, we studied 55 consecutive children with clinical and/or biochemical evidence of liver disease and circulating antinuclear (ANA), anti-smooth muscle (SMA), and/or liver-kidney-microsomal type 1 (LKM1) autoantibodies. They underwent liver biopsy, direct cholangiography, sigmoidoscopy, and rectal biopsy at presentation. Twenty-eight were diagnosed as AIH in the absence and 27 autoimmune sclerosing cholangitis (ASC) in the presence of radiological features of cholangiopathy. Twenty-six ASC and 20 AIH had ANA and/or SMA; 1 ASC and 8 AIH LKM1 autoantibody. Similarities between the 2 conditions included most clinical and biochemical parameters and a lower frequency of HLA DR4. Inflammatory bowel disease and histological biliary changes were more common in ASC; coagulopathy, hypoalbuminemia, lymphocytic periportal hepatitis, and HLA DR3 were more common in AIH. Histological biliary changes were observed in 65% of ASC and 31% of AIH patients. Eighty-nine percent responded to immunosuppression. Follow-up liver biopsies from 17 ASC and 18 AIH patients had similarly reduced inflammatory activity and no progression to cirrhosis. Sixteen follow-up cholangiograms from AIH patients and 9 from ASC patients were unchanged, while 8 ASC patients showed a progressive cholangiopathy. One child with AIH and ulcerative colitis developed sclerosing cholangitis 8 years after presentation. At 2 to 16 years (median, 7 years) from presentation, all patients are alive, including 4 ASC patients who underwent liver transplantation. In conclusion, ASC and AIH are similarly prevalent in childhood; cholangiography is often needed to distinguish between these 2 entities, which are likely to lie within the same disease process.

Adolescent↗
PubMed2001

Serum hyaluronic acid as an early prognostic marker in biliary atresia.

PURPOSE: The aim of this study was to assess whether serum concentrations of hyaluronic acid (HA), measured at diagnosis is an early biochemical marker of prognosis in biliary atresia. METHODS: Serum HA was measured at diagnosis using a radiometric assay in 84 infants with biliary atresia (BA), and related to outcome by 5 years of age. RESULTS: Serum HA was higher in the 29 patients who died or required liver transplant by 5 years of age compared with the 56 who survived to 5 years without transplant (490 +/- 216 microg/L v 262 +/- 163 microg/L; P <.001, 95% confidence intervals of the difference 145 to 311 microg/L). CONCLUSION: High serum concentrations of HA at diagnosis may help to identify at an early stage those patients with BA who have a poor prognosis and will require liver transplant by 5 years of age.

Actuarial Analysis↗
PubMed2001

Survival and outcome after hepatic artery thrombosis complicating pediatric liver transplantation.

BACKGROUND/PURPOSE: Hepatic artery thrombosis (HAT) represents a significant cause of graft loss and mortality after pediatric orthotopic liver transplantation (OLT). The incidence and etiology of this complication have been investigated in detail but relatively little is known about outcome. METHODS: A review was conducted of all children with confirmed HAT complicating OLT during a 10-year period (1990 through 1999) in a single center. HAT was established by angiography or at operation in all cases. RESULTS: From a consecutive series of 400 pediatric OLTs, there were 31 (7.8%) instances of HAT in 29 children of median age 3.8 years (range, 8 days to 16 years). Twenty-four (83%) are alive after a median follow-up of 3.6 years. Fourteen cases occurred after transplantation of whole grafts and 17 after reduced or split livers. Of the 18 episodes resulting in retransplantation, there were 5 deaths and 2 second episodes of HAT; surviving children are alive with good graft function. Of the 13 episodes managed without retransplantation, 4 patients underwent attempted early revascularisation of the graft, which was successful in 2, and the remainder initially were treated conservatively. All 13 children are alive after a median follow-up of 4.1 years (range, 0.6 to 5.8), but 5 required radiologic or surgical intervention for biliary or septic complications; biochemical liver function is normal in 8, mildly abnormal in 3, and poor in 2. Retransplantation was less likely in those who had received reduced or split grafts (7 of 17) compared with those who had received whole grafts (11 of 14), but this difference just failed to reach statistical significance (chi(2) = 3.01, 0.1 > P > .05). CONCLUSIONS: Using a selective policy of retransplantation, revascularisation, and conservative treatment, 83% of children survived HAT complicating OLT. Approximately 40% of children with HAT survived without retransplantation. J Pediatr Surg 36:888-891.

Child↗
PubMed2001

Immunohistochemistry of the liver and biliary tree in extrahepatic biliary atresia.

BACKGROUND: Progressive destruction of intrahepatic bile ducts may determine outcome in extrahepatic biliary atresia (EHBA) despite successful portoenterostomy. The aim of this study was to characterize the inflammatory infiltrate of a large series of cases of biliary atresia and relate these findings to clinical outcome. METHODS: Immunohistochemical analysis was performed on frozen tissue sections of extrahepatic biliary tree and liver biopsies obtained (August 1996 to March 1998) from 28 infants with EHBA and 8 liver biopsy specimens from age-matched controls with other cholestatic liver disorders. A semiquantitative scoring system was designed to evaluate the staining with a panel of antibodies to the CD4, CD8, CD25, CD56, CD68, CD71 antigens and to HLA-DR, ICAM-1, VCAM-1, E-selectin and LFA-1. The infants then underwent followup prospectively and divided into 2 prognostic groups at 12 months postoperatively: those who had cleared their jaundice (graded as a good outcome [n = 19]), and those who required liver transplantation or who had failed to clear their jaundice (defined as > 50 micromol/L; graded as poor outcome [n = 9]). RESULTS: CD4(+) lymphocytes and CD56(+) (NK cells) predominated in the liver of infants with EHBA as compared with controls. The infiltrating cells exhibited marked proliferation (CD71 expression) and activation (particularly LFA-1 but also CD25 expression). A smaller subpopulation of the cells also expressed VCAM and E-selectin. HLA-DR was strongly expressed on Kupffer cells and to a lesser extent on proliferating bile ducts and sinusoidal endothelium. Expression of the majority of markers was lower in the remnant bile duct tissue than in the liver of EHBA (P <.05) with only HLA-DR and LFA-1 (on infiltrating cells) and ICAM (on endothelium) expressed strongly in the remnant bile duct tissue. Although quantitatively less pronounced, all of these immunohistochemical features also were noted in non-EHBA cholestatic liver tissue. A good outcome at 12 months was associated with lower CD68 (macrophage) expression in both the liver (P <.05) and biliary tree (P <.05) and with reduced expression of ICAM-1 (P =.05) on infiltrating cells in the biliary remnant. CONCLUSIONS: Immunohistochemical patterns of immune-mediated liver injury and inflammation were prevalent features at the time of portoenterostomy. They were neither exclusive to nor characteristic of EHBA. A reduction in the expression of the macrophage marker (CD68) within the liver and biliary remnants and reduction of ICAM-1 expression on infiltrating cells in the biliary remnants appear to be associated with a better postoperative prognosis.

Antigens, CD↗
PubMed2001

Classification and genetic features of neonatal haemochromatosis: a study of 27 affected pedigrees and molecular analysis of genes implicated in iron metabolism.

Neonatal haemochromatosis (NH) is a severe and newly recognised syndrome of uncertain aetiology, characterised by congenital cirrhosis or fulminant hepatitis and widespread tissue iron deposition. NH occurs in the context of maternal disease including viral infection, as a complication of metabolic disease in the fetus, and sporadically or recurrently, without overt cause, in sibs. Although an underlying genetic basis for NH has been suspected, no test is available for predictive analysis in at risk pregnancies. As a first step towards an understanding of the putative genetic basis for neonatal haemochromatosis, we have conducted a systematic study of the mode of transmission of this disorder in a total of 40 infants born to 27 families. We have moreover carried out a molecular analysis of candidate genes (beta(2)-microglobulin, HFE, and haem oxygenases 1 and 2) implicated in iron metabolism. No pathogenic mutations in these genes were identified that segregate consistently with the disease phenotype in multiplex pedigrees. However, excluding four pedigrees with clear evidence of maternal infection associated with NH, a pedigree showing transmission of maternal antinuclear factor and ribonucleoprotein antibodies to the affected infants, and two families with possible matrilineal inheritance of disease in maternal half sibs, a large subgroup of the affected pedigrees point to the inheritance of an autosomal recessive trait. This included 14 pedigrees with affected and unaffected infants and a single pedigree where all four affected infants were the sole offspring of consanguineous but otherwise healthy parents. We thus report three distinct patterns of disease transmission in neonatal haemochromatosis. In the differentiation of a large subgroup showing transmission of disease in a manner suggesting autosomal recessive inheritance, we also provide the basis for further genome wide studies to define chromosomal determinants of iron storage disease in the newborn.

Adolescent↗
PubMed2001

Improved diagnosis of extraheptic biliary atresia by high frequency ultrasound of the gall bladder.

Ultrasound scanning using a 13 MHz probe was performed on 158 infants, aged 12 weeks or less, presenting with conjugated hyperbilirubinaemia. The gall bladder was identified in 156 infants, 35 of whom had biliary atresia. The two patients in whom no gall bladder was seen both had biliary atresia. The gall bladder shape was normal in 128 patients (9 with biliary atresia) and irregular in 28 patients (26 with biliary atresia). The gall bladder wall was regular in 121 patients (4 with biliary atresia) and irregular in 35 patients (31 with biliary atresia). Combining these findings gave a sensitivity of 91.9%, a specificity of 96.7%, a positive predictive value of 89.5%, a negative predictive value of 97.5% and an accuracy rate of 95.6% for ultrasound of the gall bladder in the identification of biliary atresia. This compares with 90%, 92.4%, 75.3%, 97.3% and 91.9%, respectively, in our previous report using a 7 MHz probe.

Biliary Atresia↗
PubMed2001

Pediatric autoimmune liver diseases: the molecular basis of humoral and cellular immunity.

Pediatric autoimmune liver disease is mainly represented by two similar liver disorders: autoimmune hepatitis (AIH) and autoimmune sclerosing cholangitis (ASC), both characterized by hypergammalobulinemia, interface hepatitis and the presence of a wide range of circulating autoantibodies. Although similar features are seen in AIH and inflammatory bowel disease, histological biliary changes are more common in ASC. In addition to their role as diagnostic markers, autoantibodies, such as anti-extractable nuclear antigen (ENA) antibodies and liver kidney microsomal antibody type 1 (LKM1) may be involved directly in inducing aggressive liver diseases. Although the cellular immune response in pediatric autoimmune liver disease has been less intensively investigated than humoral immunity, the importance of antigen specific T cells has been explored. Both alphabeta and gammadelta T cells derived from either peripheral blood and liver biopsies have highly heterogeneous TCR gene usage and cytolytic activity has been demonstrated. There have been attempts to seek triggers of liver autoimmunity and several sequences shared in common between autoantigens and hepatotropic viruses, namely hepatitis B, C and cytomegalovirus have been identified. The presence of cross-reactivity between homologous sequences, especially between HCV and cytochromes, supports the possibility that molecular mimicry plays a role in the induction of autoantibodies and autoreactive cytotoxic T cells.

Amino Acid Sequence↗
PubMed2000

Response to varicella immunization in pediatric liver transplant recipients.

BACKGROUND: Individuals undergoing therapeutic immunosuppression are at risk of severe varicella-zoster virus (VZV) infection, particularly those without evidence of previous infection. METHODS: Eleven children, median age 10 months (range 5.5 months to 7 years and 9 months) received one dose of varicella vaccine (Varilrix, SmithKline Beecham plc, UK) before liver transplantation (median interval 95 days, range 40-289 days). The serological response to varicella vaccine was evaluated retrospectively and matched with the outcome and management of any subsequent exposures to VZV. RESULTS: Three children responded postimmunization, six children showed no response, and in two children the outcome was difficult to interpret having received blood products. Four children required varicella-zoster immunoglobulin prophylaxis posttransplantation, two of whom developed mild chickenpox. CONCLUSIONS: Only 3 of 11 children developed a clear antibody response to varicella vaccine. Administration of varicella vaccine did not affect the management of subsequent VZV exposures.

Antibody Formation↗
PubMed2000

Recurrence of Langerhans cell histiocytosis in the graft after pediatric liver transplantation.

Two girls were diagnosed with Langerhans cell histiocytosis (LCH) at the age of 16 and 7 months and developed end stage chronic liver disease related to LCH-induced sclerosing cholangitis at 28 and 8 months, respectively. They received liver transplants at 34 and 14 months of age. Five months post-orthotopic liver transplantation (OLT) one of the patients developed posttransplant lymphoproliferative disease, successfully treated with a combination of surgery and reduction of immunosuppression. Fourteen months post-OLT she developed diabetes insipidus, bilateral ear discharge, and new osteolytic lesions. After transplantation both girls had mild skin reactivations of LCH, requiring minimal steroid increments. At 60 and 5 months post-OLT intrahepatic LCH recurrence was diagnosed on the basis of abnormal biliary enzymes and presence of Langerhans cells in the grafts. Initial cholangiography in both patients was unremarkable. LCH activity was controlled by maintenance chemotherapy with vinblastine, etoposide, and prednisolone. Ten months after reappearance of LCH in the liver graft a follow-up cholangiography in one of the girls demonstrated a low grade cholangiopathy. Residual elevation of liver enzymes probably represents an ongoing pathogenic process.

Cholangiography↗