Interferon treatment in children with chronic hepatitis C: long-lasting remission in responders, and risk for disease progression in non-responders.

BACKGROUND AND AIM: Large interferon-based therapeutic trials are still lacking in children with hepatitis C and the long-term safety and efficacy of interferon is unknown. This study describes the outcome of hepatitis C in 43 children enrolled in an open-label interferon trial, and were followed up to 66 months after stopping treatment. PATIENTS AND METHODS: All patients received interferon alfa2a (5MU/m(2)) thrice weekly for 6 months; children with genotype 1b received 3MU/m(2) thrice weekly for 6 additional months. RESULTS: Nine children discontinued interferon for adverse events and three were not compliant to treatment. Eight (19%, intention to treat analysis), including 2/20 (10%) with genotype 1b and 6/12 (50%) with genotypes 2 or 3, were sustained responders 12 months after stopping therapy. During further follow-up (mean+/-S.D.: 44.7+/-14.6 months), response was maintained; two non-responders cleared viremia, while a young boy progressed to cirrhosis. CONCLUSIONS: Small sample size and therapy withdrawal are the major limitations in the interpretation of our results. Nevertheless, our data, suggesting that response to interferon in children with hepatitis C is genotype-related and stable, agree with the results of large studies in adults. The outcome in non-responders was variable, including persistence of viremia and mild-moderate cytolysis (most cases), progression to cirrhosis, or eventual sustained viremia clearance.

Mimicry between the hepatitis C virus polyprotein and antigenic targets of nuclear and smooth muscle antibodies in chronic hepatitis C virus infection.

Autoantibodies to smooth muscle (SMA) and nuclear components (ANA) arise in the natural course of chronic infection with hepatitis C virus. In view of the growing evidence for 'molecular mimicry' as a mechanism of autoimmunity we investigated whether cross-reactive immune reactions between host smooth muscle/nuclear components and HCV antigens may contribute to the formation of SMA and ANA in chronic HCV infection. Computer-assisted protein database search methods were used to identify three smooth muscle (smoothelin698-717, myosin1035-1054, vimentin69-88) and three nuclear (matrin722-741, histone H2A11-30, replication protein A133-152) host antigens with the highest local sequence similarity to the HCV polyprotein and 20-mer peptides corresponding to these regions were constructed. Sera from 51 children with chronic HCV infection [median age: 8 (2-16); 27 boys], 26 SMA positive and five ANA positive, were tested for reactivity to the synthesized HCV peptides and their human homologues by enzyme linked immunosorbent assay (ELISA). Sera from patients with HBV infection and chronic liver disease of different aetiologies were used as controls. 'Double reactivity' to HCV peptides and smooth muscle/nuclear homologues was associated strongly with HCV infection (P < 0.001 for both). Humoral cross-reactivity was established as the basis for double recognition by competition ELISA. Double-reactivity to smooth muscle and HCV peptide antigens correlated with SMA positivity by indirect immunofluouresence (P = 0.05). Of 15 patients double-reactive to myosin1035-1054 and its HCV homologue, 13 recognized whole myosin by immunoblot. These results suggest that ANA and SMA in chronic HCV infection may arise, at least in part, as a consequence of cross-reactive immune responses to HCV and host smooth muscle/nuclear antigens.

An epidemiological survey of hepatitis C virus infection in Italian children in the decade 1990-1999.

BACKGROUND: A retrospective-prospective survey of Italian children with hepatitis C virus (HCV) infection was planned in 1998 to explore the epidemiologic features of infection during the past decade. METHODS: Anti-HCV-positive patients (or HCV RNA-positive infants) aged 1 month to 16 years, consecutively observed in 20 pediatric Institutions, were considered. An anonymous epidemiologic questionnaire based on clinical records was used. RESULTS: From 1990 through March 1999, 606 patients were observed (296 boys, average age 5.8 years). Maternal infection (46% of cases) and blood transfusions (34%) were the most frequent risk factors. Of 279 infected mothers, 61% did not recall a putative source of infection (by history, many could possibly have had exposure through routes such as therapeutic injections with nondisposable material), whereas 94 (34%) admitted drug abuse, including 49 (17%) coinfected with human immunodeficiency virus (HIV). Only 157 (26%) children were born after 1991: 90% of their mothers were infected (11% were HIV coinfected vs. 25% mothers of older children, P < 0.01). CONCLUSIONS: Maternal infection is a prominent source of pediatric HCV infection in Italy. The fact that most mothers had a history of covert exposure to HCV, probably through percutaneous routes that are no longer operating, and that the number of those with HIV coinfection has decreased suggests that the frequency of pediatric infection could decrease in the future.

Predictive value of Epstein-Barr virus genome copy number and BZLF1 expression in blood lymphocytes of transplant recipients at risk for lymphoproliferative disease.

Epstein-Barr virus (EBV) genome numbers and RNA transcripts from the immediate-early EBV gene BZLF1 were monitored by means of polymerase chain reaction in peripheral blood lymphocytes (PBLs) of 44 children who received liver transplants. The 2 tests were compared, using several parameters to assess their value as predictors of posttransplantation lymphoproliferative disease (PTLD). All patients were infected with EBV. BZLF1 mRNA was positive in 70% of patients, with highest expression in those with largest virus load. Four patients developed PTLD that could not be unequivocally diagnosed by any of the parameters considered alone. Sensitivity of EBV genome number (>/=40,000 EBV copies/10(5) PBLs) and BZLF1 mRNA (BZLF1:glyceraldehyde-3-phosphate-dehydrogenase ratio >/=0.5) was 100%. Specificity of each of the 2 tests alone (98% and 58%, respectively) improved (to 100% and 83%, respectively) when measurement of serum IgG level was included. Because decreased virus load, but not BZLF1 mRNA expression, accurately predicted favorable responses of PTLD to therapy, monitoring of EBV genome numbers alone appears sufficient in children with liver transplants.

Long term effect of alpha interferon in children with chronic hepatitis B.

BACKGROUND/AIMS: The purpose of this study was to better define the long term prognosis of infection and disease in children with chronic hepatitis B treated with interferon (IFN) alpha. PATIENTS: A total of 107 children with chronic hepatitis B who received IFN alpha for three or six months in two clinical trials were followed for a mean period of 69 (17) months. Response to treatment was defined as loss of hepatitis B e antigen (HBeAg) within 12 months after stopping treatment. A control group of 59 patients was also followed for a shorter mean time (46 (19) months). RESULTS: Sixteen (15%) treated children responded during therapy and 18 (17%) during post-treatment follow up; 31 (29%) non-responders lost HBeAg during subsequent years. High pretreatment levels of transaminases and a greater histological activity index were predictors of response. Kaplan-Meier estimates of cumulative HBeAg clearance rates at five years were similar between treated patients (60%) and controls (65%). After HBeAg clearance, all cases lost hepatitis B virus DNA and 94% had normal transaminase levels. Loss of hepatitis B surface antigen (HBsAg) occurred in four (25%) patients who responded during treatment but in none of the other treated or untreated patients. CONCLUSIONS: After five years' observation, the proportion of treated children with sustained HBeAg clearance comprised an equal number of responders and non-responders and did not differ from that observed in untreated controls, suggesting that IFN simply accelerated a spontaneous event. However, IFN significantly improved the rate of HBsAg loss in cases with more prominent disease activity who were early responders, and may be particularly useful in this type of patient.

Low virological response to interferon in children with chronic hepatitis C.

BACKGROUND/AIMS: Children with chronic hepatitis C were recently found to have higher rates of sustained response to interferon compared to adults. The aim of this study was to verify the response to interferon using frequent viremia measurements. METHODS: Sera from 25 children (13 males; mean age 7.9 years) with chronic hepatitis C, treated with recombinant alpha-2b interferon for 12 months, were tested for liver function tests and viremia levels for a median of 27.5 months. Autoantibodies were evaluated during and after interferon. RESULTS: Fifteen patients completed 12 months of interferon; treatment was stopped in 10 other patients. In 11 (44%) patients viremia was undetectable already at the second administration of interferon; one of them remained viremia-free up to the end of follow-up and had persistently normal alanine-aminotransferase levels (complete sustained responder). A complete sustained response was observed only in one other patient, who normalized alanine aminotransferase and cleared viremia from the 3rd month of therapy. Three patients with persistent viremia normalized alanine-aminotransferase from the 3rd week of therapy up to the end of follow-up (biochemical sustained responders). Viremia was undetectable during treatment in four patients, who stopped interferon because of worsening in hypertransaminasemia. Three of these four patients were anti-liver-kidney microsomal type 1-positive. CONCLUSIONS: In this study the response rate to interferon was very low and viremia and transaminase findings were often discordant.

Chronic cryptogenic hepatitis in childhood is unrelated to hepatitis G virus.

OBJECTIVES: The aim of this study was to define the features of chronic cryptogenic hepatitis (CCH) in childhood and to investigate whether it is related to hepatitis G virus infection. METHODS: Forty-six children (24 males; age range, 1.5 to 17 years) with CCH were studied. CCH was diagnosed when serum alanine aminotransferase concentrations were more than 1.5 times normal for longer than 6 months without any apparent cause of liver disease. RESULTS: No patient had acute symptomatic onset or had received a blood transfusion. Three had undergone minor surgical procedures. All appeared to be healthy during follow-up (median, 4.2 years; range, 1 to 10 years). Hypertransaminasemia was the only aberrant liver function test. Elevated serum alanine aminotransferase values alternated with normal values in 40 children (86.9%). Five children (10.8%) had a spontaneous sustained (>12 months) remission of hypertransaminasemia. Twelve (26%) had laboratory signs of autoimmunity, but none fulfilled the criteria for autoimmune hepatitis. Of 20 children who underwent liver biopsy, 13 (65%) had minimal chronic hepatitis, 4 (20%) had mild chronic hepatitis and 3 (15%) had moderate chronic hepatitis. Serum hepatitis G virus RNA was detected in 2 girls (4%) whose risk factor was a hepatitis G virus-infected mother and a minor surgical procedure, respectively. In 12 families at least 1 other member had chronic liver disease. CONCLUSIONS: Childhood CCH seems to be a symptomless disease characterized by isolated hypertransaminasemia with onset during the first 4 years of life and mild to moderate histologic liver lesions. Although the frequency of spontaneous remissions is low, childhood CCH seems, in the short run, to be a nonprogressive disease. Hepatitis G virus does not play a major role in CCH.

Safety and immunogenicity of hepatitis A vaccine in infants: a candidate for inclusion in the childhood vaccination programme.

Forty-eight infants received a single dose (720 ELISA units = 0.5 ml) of inactivated hepatitis A vaccine at the fifth month of age with booster at the 11th month of age, together with the second and third doses of the vaccines compulsory under Italian law (diphtheria, tetanus, oral polio and hepatitis B). Overall, the seroconversion rate was 100%. The anti-HAV geometric mean titre (GMT) reached 3,021 mIU/ml in infants born to anti-HAV-negative mothers, but only 399 mIU/ml in infants born to anti-HAV-positive mothers. Hepatitis A vaccine was immunogenic, safe and well tolerated without significant side-effects. There seems to be no reason for not including it in childhood vaccination programmes particularly in low endemic HAV areas.

Mimicry between the hepatitis B virus DNA polymerase and the antigenic targets of nuclear and smooth muscle antibodies in chronic hepatitis B virus infection.

Autoantibodies to nuclear and smooth muscle are common in hepatitis B virus (HBV) infection. To understand their origin, we scanned protein databases and found that HBV-DNA polymerase (HBV-pol) shares 7-9 amino acid sequences with nuclear (MHC II trans-activator, nuclear pore core protein, nuclear mitotic apparatus, and polymyositis sclerosis Ag) and smooth muscle proteins (caldesmon and myosin). Twenty-mer peptides with relevant homologues and an irrelevant control peptide were constructed and ELISAs were established. Sixty-five children with chronic HBV infection, 104 patients with other chronic liver diseases (CLD), 36 patients with extrahepatic autoimmune diseases, and 24 healthy controls were investigated. Double reactivity to HBV-pol peptides and corresponding self homologues was observed in 40% of HBV-positive patients as compared with four (4%) with other chronic liver diseases, two (6%) with extrahepatic autoimmune diseases, and in none of the healthy controls (p < 0.001 for all). Double reactivity to myosin or caldesmon peptides and their HBV-pol homologues was associated with anti-smooth muscle Ab positivity by immunofluorescence (p < 0.05 for both). HBV-positive sera double reactive for myosin or caldesmon and their homologous HBV-pol peptides also reacted with the native proteins on immunoblot. Fifty to ninety percent Ab inhibition to individual HBV-pol and HBV-pol99-118 peptides was noted by preincubation with individual HBV-pol/self homologue peptide and native proteins, respectively, but not with control peptide. Our results show that cross-reactive immunity targeting homologous sequences of viral and self proteins may partly account for autoantibody production in HBV infection.

Macroenzyme investigation and monitoring in children with persistent increase of aspartate aminotransferase of unexplained origin.

Ten children with asymptomatic persistent cryptogenic increased serum levels of aspartate aminotransferase (AST) were screened for detection and monitoring of AST macroenzyme (macroAST). MacroAST was found in 4 patients; their serum AST levels were significantly higher than in those without biochemical evidence of macroAST (mean +/- SD: 515 +/- 433 and 78 +/- 16 IU/L, respectively; P = .0095). MacroAST was a persistent, benign phenomenon and was probably not congenital.

Autoantibody prevalence in children with liver disease due to chronic hepatitis C virus (HCV) infection.

HCV infection and interferon-alpha (IFN-alpha) therapy have been associated with autoimmunity. To assess whether chronic liver disease (CLD) due to HCV infection or its treatment with IFN-alpha cause autoimmune manifestations, the prevalence of tissue autoantibodies in 51 children with chronic HCV infection and 84 with other CLD was analysed by standard techniques. Sixty-five percent of patients with chronic HCV infection, 66% with chronic hepatitis B infection and 60% with Wilson's disease were positive for at least one autoantibody. In the 51 subjects with chronic HCV infection (29 treated with IFN-alpha, 22 untreated), tested on 165 occasions over a median of 9 months (range 5-42 months), autoantibodies to nuclei (ANA), smooth muscle (SMA), gastric parietal cell (GPC) and/or liver kidney microsomal type 1 (LKM-1) were similarly prevalent in treated and untreated patients (90% versus 68%, P = 0.12). Positivity for SMA was present in 67%, GPC in 32%, ANA in 10%, LKM-1 in 8% of cases. Treatment with IFN-alpha had to be suspended due to transaminase elevation in one SMA-positive, one ANA-positive but in three of four LKM-1-positive patients. Our results show that: (i) autoantibodies are common in viral-induced hepatitis and Wilson's disease; (ii) positivity for SMA, GPC, ANA is part of the natural course of chronic HCV infection, their prevalence being unaffected by IFN-alpha; and (iii) IFN-alpha should be used cautiously in the treatment of LKM-1/HCV-positive patients.

Further delineation of the molecular pathology of Wilson disease in the Mediterranean population.

This study presents the update results of an ongoing project on the delineation of the spectrum of mutations at the Wilson disease (WD) gene in WD patients of Mediterranean origin. In studying 59 patients, of whom were 26 Continental Italians, 22 Sardinians, 9 Turkish, and 2 Albanians, we have found 31 novel and three known mutations. Of the novel mutations, 3 are deletions, two nonsense, 2 splice or consensus splice site, and 24 missense. The large majority of the missense mutations lie in evolutionary conserved regions of the WD gene of documented functional importance. Most of our patients were compound heterozygotes, and only a few were homozygotes. In addition, three polymorphisms were detected. By adding the new data to those previously reported by our group, we have to date detected 85% of mutations in the WD chromosomes from Continental Italians, 30% from Sardinians, 81.7% from Turkish and 66.7% from Albanians. Most of the mutations characterized are rare, and only a limited number are common. Of the common mutations 5 were found in Continental Italians, two in Sardinians and a single one in Turkish. Because there are so many causative mutations of the disease, the preclinical and prenatal diagnosis of WD should be carried out by a combination of mutation and linkage analysis.

Chronic unexplained liver disease in children with primary immunodeficiency syndromes.

Liver disease may be found in patients with primary immunodeficiency syndromes because of the high risk of infection with hepatotropic viruses related to the treatment with blood derivatives. The prevalence of liver disease in these patients and its etiology, however, is still not completely understood. We have evaluated the prevalence and the etiology of liver disease in children with different forms of primary immunodeficiencies. Thirty patients included in the study underwent molecular studies to detect common hepatotropic viruses, including hepatitis C and G viruses. Liver involvement was found in 11 of 30 (36.6%) patients. All patients with liver disease had deficiencies of specific immunity, with a prevalence in this subgroup of 47.8%. Liver disease was more severe in patients with T and B cell combined immune disorders than in those with a selective T cell immunodeficiency. Moreover, the severity of the disease correlated with an overall more rapid fatal outcome. A viral etiology was found in only six of these patients, whereas in the remaining five patients, no cause of liver injury was identified. In the virally infected patients, hepatitis C virus was the most common viral agent. In patients with immunodeficiencies, there is a high prevalence of liver disease not fully explained on the basis of the common viral infections.