Lymphoblastoid interferon alfa treatment in chronic hepatitis C.

Interferon is becoming the standard treatment in adults for chronic hepatitis C. Twenty one children with histologically proved chronic hepatitis C (10 boys, range 2.5-13 years), who were otherwise healthy, were enrolled in a randomised controlled study to test their response to interferon alfa. Eleven children were treated with lymphoblastoid interferon alfa (3 million units/m2) for 12 months; 10 children received no treatment. All had raised transaminases and positive antihepatitis C virus (HCV) antibodies and HCV-RNA. Alanine aminotransferase (ALT) serum levels became normal in five (45%) treated patients after a mean of three weeks (range 1-6 weeks) and no relapse had occurred by the end of follow up (30th month). Only one (10%) untreated patient had normal ALT serum levels from the 11th until the 30th month. Disappearance of serum HCV-RNA, persisting throughout the follow up period, was observed in the six children (five treated) whose ALT became normal. Biopsy specimens in treated patients showed a significant improvement in Knodell''s score (median (SD) basal 9.0 (2.2); final 2.0 (0.4)). Interferon treatment was well tolerated in all. This study confirms the efficacy of interferon in children with chronic hepatitis C, not only by restoring normal ALT serum levels, but also viral clearance and histological amelioration of liver inflammation. Contrary to reports in adults no biochemical and virological relapses occurred in responder children.     

Liver histology and alanine aminotransferase levels in children and adults with chronic hepatitis C infection

BACKGROUND: Chronic hepatitis C is often a mild disease in children, but whether this is related to younger age or shorter duration of infection is unclear. Histologic severity has been shown to correlate with duration of infection regardless of age. OBJECTIVES: We compared histologic findings in children and adults with chronic hepatitis C while controlling for sex, duration of infection, hepatitis C virus (HCV)-RNA level, and genotype. METHODS: Twenty-one children and 52 adults whose infection was less than 20 years in duration and who had undergone a liver biopsy were included. Two blinded liver pathologists reviewed the liver biopsies and scored inflammatory activity and fibrosis using the modified Knodell scoring system. RESULTS: The groups were the same with respect to HCV-RNA level (P=0.8), and genotype (P=0.6) but differed in duration of disease (P=0.01) and sex composition (P=0.005). Covariate analysis showed no influence of genotype, duration of infection, or HCV-RNA level on outcome. In controlling for sex, children had significantly milder liver disease and alanine aminotransferase (ALT) elevations. CONCLUSIONS: With equal duration of infection, HCV-RNA level, and genotype, children have lower serum ALT levels and less severe liver disease than adults infected with HCV.     

Hepatitis C virus infection and interferon therapy in patients with Down syndrome.

BACKGROUND: The clinical features of hepatitis C virus (HCV)-associated liver diseases, or the efficacy of interferon (IFN) therapy in children with Down syndrome (DS) remain to be elucidated. The purpose of the present paper was to survey the features of liver diseases in this subset of children and evaluate the efficacy of IFN treatment in those patients. METHODS: A questionnaire was sent to 41 members of the Japan Society of Pediatric Hepatology. Ten of them reported on 11 patients with DS who had concomitant chronic HCV infection, providing information on liver disease and the response to IFN treatment. RESULTS: Interferon therapy of 24 weeks duration using natural IFN-alpha was instituted in six of the 11 patients with DS, but none of the six patients cleared HCV-RNA from their serum. Among 12 age- and sex-matched control children who were treated with IFN using the same regimen against chronic HCV infection, half of them had a favorable response to IFN therapy with a sustained clearance of HCV-RNA from their serum. The major baseline features including alanine aminotransferase levels, HCV genotype and viral load were not apparently different between the six patients with DS and the 12 controls. CONCLUSIONS: IFN therapy for HCV infection in patients with DS may be unfavorable as compared with non-DS children.     

Lamivudine treatment for chronic hepatitis B infection in children unresponsive to interferon

BACKGROUND/AIMS: Lamivudine is a potent inhibitor of hepatitis B virus (HBV) replication. This prospective open study reports the results of lamivudine treatment in children with chronic hepatitis B infection who did not respond to previous interferon treatment. PATIENTS AND METHODS: Lamivudine, 3 mg/kg/day (maximum, 100 mg/day), was given for 52 weeks to 20 children and adolescents, ages 8.5 to 19 years, with chronic hepatitis B infection who had been treated with interferon 2 to 5 years earlier. We evaluated virologic and biochemical responses, the occurrence of YMDD mutants and adverse effects. RESULTS: All children were HBV DNA+, hepatitis B e antigen (HBeAg) /anti-hepatitis B e antibody- at start of treatment. At the end of 1 year, HBV DNA declined by 95% in all patients, and 8 of 18 (44%) had sustained undetectable HBV DNA by hybridization assay. Median pretreatment alanine aminotransferase (ALT) x1.5 upper limit of normal decreased to ALT x0.9 upper limit of normal after 1 year. One child became HBeAg-negative. YMDD mutants were detected in 11 of 17 (65%) children after 1 year of lamivudine treatment. Among children with YMDD mutant variants, 54% maintained normal ALT values and 45% had undetectable HBV DNA by hybridization assay. No adverse effects were observed. CONCLUSIONS: Children with chronic hepatitis B infection treated with lamivudine after failure of interferon therapy had decreased HBV replication and improved ALT values. However, lamivudine treatment resulted in an exceptionally high rate of lamivudine-resistant mutants and low HBeAg seroconversion rate.     

Relation between serum hepatitis C virus-RNA levels and efficacy of interferon-β therapy

We performed two courses of interferon-β (IFN-β) to a child with chronic hepatitis C. A complete response was not obtained by the first interferon treatment, however, the results of the second treatment differed from those of the first. Hepatitis C virus (HCV)-RNA remained negative and both aspartate aminotransferase and alanine aminotransferase levels remained normal after completion of the second course. From these results we estimated that HCV-RNA levels before IFN therapy could be significantly associated with the efficacy of this treatment. The serum level of HCV-RNA was 10⁶ copies/50 μL before the first treatment, but was 10³ copies/50 μL before the second course. We conclude that IFN therapy to children with hepatitis C should always be directed at providing a cure. Even if the clinical effects of the first course are minimal decreasing quantities of HCV-RNA still offer hope for cure by subsequent readministration.     

Mother-to-infant transmission of hepatitis C virus

Anti-hepatitis C virus (HCV) antibodies and HCV-RNA were measured in the sera of 22 anti-HCV positive, HIV-1 negative mothers and their infants. ELISA and RIBA II were used for anti-HCV determination. HCV-RNA was measured by a nested polymerase chain reaction. HCV-RNA was found in 12 of 22 mothers. All 22 children were followed for 12 months. All were anti-HCV positive by the fourth month; 18 became anti-HCV negative between the 8th and 12th month. HCV-RNA was detected in 5 of 22 infants in the fourth month. They remained HCV-RNA positive. All children born to HCV-RNA negative mothers were HCV-RNA negative while 5 of 12 babies born to HCV-RNA positive mothers were infected. All five infected babies were born to mothers infected through transfusions or drug use. ALT levels in mothers seemed to have no effect on mother-to-infant transmission. Hence evidence for perinatal transmission of HCV from HCV-RNA positive mothers was demonstrated in the present study.     

Interferon-alpha treatment for chronic hepatitis C in children

Interferon-alpha therapy has been proven efficient in chronic hepatitis C infection. Although it has been used as a standard therapy in adults, there are limited data on benefits of interferon treatment in children. We conducted a study of recombinant interferon-alpha therapy in 10 children with chronic hepatitis C. They had high aminotransferase values and positive antibodies to hepatitis C virus and HCV-RNA for at leas six months. Interferon-alpha was given at a dosage of 5 million units/m2 body surface three times a week for six months. At the end of therapy, five (50%) of the patients had complete response and two partial response. Three patients were nonresponders. Eight of the patients could be followed up for six months after stopping therapy, at which point one of the four complete responders and a partial responder relapsed. One of the three nonresponders had complete response at 12 months. Eventually, four (50%) of eight patients were complete responders. All of the nonresponders were the patients with previous malignant diseases. These findings suggest that interferon-alpha has beneficial effects in children with chronic hepatitis C, and a six month therapy seems to be reasonable. Patients with underlying malignant disease are not good candidates for interferon treatment.     

Virus genotype 1b and long-term response to interferon alpha monotherapy in children with chronic hepatitis C

Interferon alpha (IFN-) remains the basic modality in the treatment of chronic hepatitis C in children, but the effects of therapy are still unsatisfactory. The aim of this study was to evaluate parameters linked to IFN- response within a 2-year period. Human C virus (HCV) infected children (n=34) were subdivided into IFN-treated (n=20) and IFN-untreated (n=14 control) groups. The IFN-treated group received a dosage 3 MU of IFN- three times a week for 24 weeks. Liver biopsy was performed in all IFN-treated children and the HCV genotype was determined before the start of the study. Patients were sequentially screened for alanine transaminase (ALT) activity and tested for the presence of HCV-RNA in serum. All patients had either mild persistent or moderate active hepatitis, which was diagnosed from the liver biopsy. In the IFN-treated group ALT normalisation was observed by the end of treatment in 9/20 patients, but after 6 months 10 patients (50%) had sustained ALT normalisation and in 4 of them the virus was eliminated. They continued to show these features up to the end of the observation period (2 years). Eighteen out of 24 children tested had 1b genotype of virus. Out of 10 responders, all patients who were clear of HCV had the 1b genotype. The median age of responders (6.0, range 3.8–16) was significantly lower than non-responders (14.0, range 4–15) In the control group none of the children were clear of HCV-RNA. Conclusion: The negative predictive effect of HCV genotype 1b in the course of IFN- treatment may be not valid in children and other features have to be taken into account in the assessment of the efficacy of therapy.Abbreviations HCV human C virus - RNA ribonucleic acid - PCR polymerase chain reaction - ALT alanine aminotransferase - RBC red blood cells - HBsAg hepatitis B surface antigen - ELISA enzyme linked immunosorbent assay - CMV cytomegaly virus - IFN interferon - MU mega units - ETR end of treatment response - SR ALT sustained biochemical (ALT) response - HAI histological activity index - R responders - NR non-responders - U/l units per litter - CPH chronic persistent hepatitis - CAH chronic active hepatitis - APC antigen presenting cells - MHC major histocompatibility complex - ALL acute lymphoblastic leukaemia - CML chronic myelogenous leukaemia     

Efficacy of interferon-α2b treatment in children with chronic hepatitis B who have previously undergone therapy for cancer

BACKGROUND: The aim of the present study was to evaluate the efficacy of treatment with recombinant interferon (IFN)-alpha2b in 12 children with chronic hepatitis B who had previously undergone therapy for cancer. METHODS: Nine children had acute leukemias and the other three children had solid tumors. The mean (+/-SD) age of the children was 8.4+/-3.8 years (range 4-16 years). All cases were hepatitis B virus (HBV)-DNA positive and 11 were hepatitis B e antigen (HBeAg) positive. One was anti-HBe positive (mutant strain). Four cases were anti-delta IgG positive. Liver biopsy revealed chronic hepatitis B in 11 patients and cirrhosis in one patient. Interferon-alpha2b was given at a dose of 5 MU/m2 three times a week, subcutaneously, for 12 months. RESULTS: Elimination of serum HBV-DNA was obtained in three cases, but a further three patients demonstrated a marked decrease in HBV-DNA levels after therapy. Three of 11 patients seroconverted from HBeAg to anti-HBe. Alanine aminotransferase (ALT) levels returned to normal in three of nine cases in whom the ALT levels were high before treatment. At the end of therapy, the mean histologic activity index score was significantly diminished (P = 0.0039). CONCLUSIONS: In conclusion, a 12 month course of IFN-alpha2b induces some beneficial effects on virologic, biochemical and histologic indices in children with chronic hepatitis B who have previously undergone therapy for cancer.     

Comparison of standard and high dosage recombinant interferon alpha 2b for treatment of children with chronic hepatitis B infection

BACKGROUND: Interferon is currently the most useful therapeutic agent for chronic viral hepatitis. The aim of this study was to compare the efficacy of standard and high dosages of interferon in children with chronic hepatitis B virus (HBV) infection. METHODS: Thirty children with chronic hepatitis B infection were randomly assigned to receive 5 million units/m2 body surface area (Group I) or 10 million units/m2 body surface area (Group II) recombinant interferon alpha 2b three times weekly for 6 months. Patients were followed for at least 6 months (range, 6 to 18; median, 9 months) after the end of therapy, by physical and serologic examination every 3 months. RESULTS: Clearance of HBV DNA occurred in 4 (27%) patients from Group I and 9 (60%) patients from Group II at the end of therapy. Hepatitis B e antigen (HbeAg) clearance was 7% (1 patient) and 53% (8 patients) in the two groups, respectively (P < 0.05). HBV DNA was undetectable in 40 and 60% of the children at the 12th month of randomization in Groups I and II, respectively. HBeAg/antibody to HBeAg seroconversion was found in 33% (5 patients) who received standard dosage and 60% (9 patients) in the high dosage group. Sustained complete response (normal alanine aminotransferase, negative HBeAg and HBV DNA at 12th month) was obtained in 5 and 9 patients respectively from groups I and II (P > 0.05). Only mean baseline serum alanine amino-transferase concentrations were predictive of response to interferon. CONCLUSIONS: A 6-month course of interferon alpha 2b in children with chronic HBV disease was well-tolerated by most patients. Sustained suppression of HBV was obtained in 60% of patients with high dosage interferon and in 33% of the patients receiving standard dosage. Although these results were not statistically significant, studies with more patients are needed to ascertain whether high dosage improves the response rate.     

Chronic liver disease after treatment of malignancies in children]

Chemotherapy, which has greatly improved the prognosis of children with malignant diseases, is potentially hepatotoxic. Furthermore, there is a risk for viral hepatitis acquired by blood products. In this study we looked for hepatotoxicity and for chronic viral hepatitis during and after chemotherapy in 50 unselected children with malignant diseases. 29 children had been treated for leukemia or lymphoma, 19 for solid tumors, 2 for histiocytosis. All patients had been treated before 1991 and had received blood products not screened for hepatitis C-antibodies. In 18 girls and 32 boys aged 12.3 years (range 6.7-24.5 years) hepatitis B- and hepatitis C-serology and liver function tests were measured during a routine check-up 3.6 years (range 0.5-11.8 years) after the last chemotherapy. Liver function tests during chemotherapy were reviewed retrospectively. During chemotherapy 86% of children showed increased ALT and AST levels, 10% had levels above 500 U/l. At follow up 16 children (32%) had pathological liver function tests, especially slightly increased AST and ALT, 13 of these 16 patients had chronic hepatitis C. In contrast only 2 of 34 patients with normal liver function tests had a viral hepatitis (p = 0.001). Patients with elevation of AST and ALT above 100 U/l during chemotherapy had significantly more often a viral hepatitis than those with normal or slightly elevated aminotransferases. Our study shows that hepatocellular damage is a frequent complication following chemotherapy. However this progresses to chronic liver disease very rarely unless the patient acquired a viral hepatitis. The prevalence of chronic hepatitis C was very high in our patients. As screening of blood products for hepatitis C-antibodies is routinely performed since 1991 this problem is likely to have decreased.     

Treatment of chronic hepatitis C in children

Since the discovery of hepatitis C virus (HCV) in 1989, significant advances have been made in our understanding of this important viral pathogen. Children at risk for HCV infection include recipients of potentially contaminated blood products and organ transplants, and infants born to HCV-infected mothers. Chronic HCV infection is usually asymptomatic in children but active hepatitis, cirrhosis and hepatocellular carcinoma can occur. The development of treatment strategies for chronic hepatitis C in children has directly evolved from clinical trials in adults. Sustained virologic response, defined by undetectable HCV RNA in serum 24 wk after completion of treatment, occurs in approximately 36% of children treated with conventional interferon alone and in about 50% of those given conventional interferon in combination with ribavirin. Pegylated interferon-based treatment regimens are better than those based on conventional interferon in adults but little is known about pegylated interferon in children. Factors associated with a favorable response to antiviral therapy in children are similar to those in adults and include infection with HCV genotype 2 or 3 and low pretreatment serum HCV RNA levels. Treatment related adverse events in children include 'flu-like' syndrome, fatigue, anorexia, weight loss, depression, anemia, leukopenia and thrombocytopenia.     

Alpha interferon and lamivudine combination therapy for chronic hepatitis B in children

BACKGROUND: Lamivudine is a new alternative therapeutic agent for chronic hepatitis B, in which alpha interferon (IFN-alpha) monotherapy is not successful enough. Published reports have revealed no satisfactory data on IFN-alpha and lamivudine combination therapy in children. The aim of this study is to investigate the efficacy and safety of this combination therapy in children with chronic hepatitis B. METHODS: Children with chronic hepatitis B were given either IFN-alpha and lamuvidine (group 1, n = 47) or IFN-alpha alone (group 2, n = 30). Alpha interferon was administered as 5 million U/m2 s.c., thrice a week for 6 months and lamivudine 4 mg/kg per day p.o., maximum 100 mg, for 1 year. Clinical examination was performed; blood cell counts and serum alanine aminotransferase (ALT) and amylase were studied at each visit. At the third, sixth and twelfth month, serological markers were determined. RESULTS: End of therapy response was achieved in 19 (40.4%) patients in group 1 and in 14 (46.7%) children in group 2 (P > 0.05). In group 1, pretreatment serum ALT and hepatic activity index (HAI) were statistically higher in children who responded to therapy (P < 0.005). In group 2, mean serum ALT was higher and hepatitis B virus (HBV) DNA was lower in responders. Sustained response rate was 40.4 versus 43.3% in two groups. CONCLUSION: The response rate of IFN-alpha and lamivudine combination therapy in children with chronic hepatitis B was similar to that of IFN-alpha monotherapy. High ALT level and HAI, rather than low HBV-DNA level were found to be important predictors of response.     

Increased risk of chronic hepatitis in children with cancer

BACKGROUND: There is a risk of viral hepatitis for children with cancer. Both hepatitis B virus (HBV) and hepatitis C virus (HCV) infections in countries with high prevalence cause major problems in the management of cancer patients. In this study, we evaluated the incidence and chronicity of HBV and HCV infections in children with malignant diseases receiving chemotherapy. PROCEDURE: One hundred ninety-eight children with cancer (mean age = 7.5 +/- 2.5 years) and 100 healthy children as a control group were screened for HBV and HCV. Liver function tests, the number of transfusions, HBV and HCV serology were regularly monitored. In seropositive children, HBV-DNA and HCV-RNA were measured. Chronic hepatitis was defined as having an alanine aminotransferase (ALT) level three times of upper normal limit, positive HBV and HCV antigenemia for longer than 6 months. Liver biopsies were performed in all children with chronic hepatitis. The relationship between the chronic hepatitis and study parameters was statistically analyzed. RESULTS: HBsAg positivity, anti-HCV, and mixed (HBV and HCV) infection were found in 11.6, 5.5, 2% of children, respectively. Most HBV infected children developed chronic hepatitis (48%) while 26 and 21.7% became carriers and immune, respectively. One died of acute fulminant HBV hepatitis. Of HCV infected children, 63.6% also had positive HCV-RNA. Four children with mixed infection (100%) all progressed to chronic hepatitis. In this setting, chronic hepatitis was observed in 22 of 38 infected children (57.8%). The majority had leukemia and lymphoma. Children with HBsAg antigenemia developed chronic hepatitis in shorter time than HCV positive children (median 13 months vs. 51 months, P < 0.001). CONCLUSION: We observed an increased incidence of chronic hepatitis and even mortality due to HBV infection. This suggests that HBV and HCV infections are serious causes of morbidity and mortality in children with cancer.     

Interferon for chronic hepatitis C in patients cured of malignancy

Six patients with chronic hepatitis C who were cured of malignancy were treated with recombinant interferon-alpha at the dose of 4 MU/m² for 12 months; the post-treatment follow up period was 12 months. Therapy was stopped within 6 months in three patients because of persistently abnormal alanine aminotransferase levels. In the remaining three patients, a complete normalization of alanine amnotransferase levels was obtained during treatment but it was not maintained after the end of interferon therapy. In addition, no patient cleared hepatitis C virus ribonucleic acid in serum. These results suggest that recombinant interferon is not effective in patients with chronic hepatitis C who were cured of a previous malignancy.     

Chronic hepatitis B infection: long term comparison of children receiving interferon alpha and untreated controls

OBJECTIVES: To investigate the virological outcome of chronic hepatitis B (CH-B) in children who received interferon alpha (IFN) compared with no treatment. METHODS: Seventy-four children with CH-B (median age, 6.1 years; 44 boys) selected from a cohort of 158 cases were included and divided into two groups: IFN-treated (n = 37) and control (n = 37). The controls were matched with the treated children by baseline alanine aminotransferase (ALT) levels, sex and age. The Kaplan-Meier method was performed to estimate the time to clearance of hepatitis B e antigen (HbeAg) and hepatitis B surface antigen (HbsAg). RESULTS: Mean duration of follow-up was comparable in two groups (5.2 +/- 3.8 years in treatment group versus 5.2 +/- 3.7 years in control group, NS). HBeAg and HBsAg loss occurred in 20 (54.1%) and three treated children versus 13 (35.1%) and one untreated children (NS), respectively. The 7-year cumulative HBeAg and HBsAg clearance rates were 47.5% and 8.9% after the first visit in the treatment group versus 33.5% and 4.0% in untreated children (NS), respectively. Elevated baseline ALT (two times upper limit of normal) had a significant effect on the long-term cumulative rate of HBeAg seroconversion in treated patients (P = 0.01) but not in the untreated group. CONCLUSIONS: These findings show that the overall long-term virological outcome does not differ significantly between IFN-treated and untreated children but that a significant benefit of treatment on the long term rate of HBeAg seroconversion is obtained in children with higher baseline ALT levels.     

Interferon treatment for chronic hepatitis B: enhanced response in children 5 years old or younger

OBJECTIVE: To test the hypothesis that there is an improved response to interferon in children with chronic hepatitis B (HBV) who are < or =5 years of age. STUDY DESIGN: Retrospective chart review of 22 consecutive children with chronic HBV (ages 17 months to 17 years; median, 83.9 months; 14 male, 8 female) treated with interferon-alpha2b. RESULTS: Ten patients (48%) responded to treatment [HBeAg (-), Anti-HBe (+), HBV DNA (-), HBsAg (+) and normal alanine aminotransferase/aspartate aminotransferase (ALT/AST) at 6 months after treatment], and 5 seroconverted HBsAg [above plus HBsAg negative and anti-HBs (+)]. Seven of 9 patients (78%) < or =5 years of age responded (5 cleared HBsAg). Three of 13 patients (23%) >5 years of age responded. Patient age at treatment was significantly lower in responders (63 +/- 70 months) versus nonresponders (104 +/- 55 months, P =.005). AST, ALT, and HBV DNA at the start of treatment were not different between responders and nonresponders or between patients < or =5 and >5 years old. CONCLUSIONS: Interferon treatment may be more effective in younger children with chronic hepatitis B.     

Update on prevention and treatment of viral hepatitis in children.

Viral hepatitis is a persisting concern. Outbreaks of hepatitis A occur in developed countries where only 10% to 20% of the population is seroprotected. The disease may cause fulminant liver failure and death. People who are targeted for vaccination include intravenous drug users, homosexuals, and chronic hepatitis patients. Secondary prophylaxis of household contacts is an efficient way to prevent secondary cases. Universal vaccination is now in progress for hepatitis B. Vaccination failure may occur in low birth weight infants, or in infants infected in utero. Chronic carriers of viral hepatitis may progress to cirrhosis and hepatocarcinoma, the latter risk being most important for men infected at birth. Alcohol intake should be avoided in carrier adolescents. Interferon is able to triple the rate of hepatitis B e antigen loss and decouple the rate of hepatitis B s antigen loss after one year, shortening disease evolution and, it is to be hoped, decreasing the risk of unfavorable outcome. Similarly, lamivudine increases by four times the rate of hepatitis B e antigen loss in adults. However, precore mutants may be selected by immune pressure after seroconversion in children, and tyrosine-methionine-aspartate-aspartate (YMDD) mutations appear in 15% of patients treated with lamivudine after 1 year. Hepatitis C is mainly acquired during childhood via true vertical transmission. The risk of acquiring Hepatitis C is related to the presence and amount of RNA for hepatitis C virus in mothers at the time of birth. The infection rate for the hepatitis C virus is higher in children from mothers who have tested positive for HIV, and higher if these children are themselves coinfected with HIV. Treatment with interferon alone has a poor rate of efficiency, although pediatric studies remain scarce. Combination treatment using ribavirin plus interferon yield a higher rate of success in eradicating viral infection in adults.     

Serum levels of hepatitis C virus RNA in infants and children with chronic hepatitis C.

BACKGROUND: The role of serum hepatitis C virus (HCV) load in infectivity, disease activity, and response to interferon treatment has been investigated in adults, and controversial results have been obtained. Little is known about HCV load in infants and children with HCV infection. PURPOSE: To investigate the relation between HCV load in serum and features of associated liver disease in infants and children with HCV infection. METHODS: Hepatitis C viral load was investigated in serial samples in 43 children with chronic HCV infection, including 32 patients aged 4 to 16 years infected by different routes and 11 vertically infected infants observed prospectively since birth. RESULTS: Overall viremia ranged between 2.7 and 6.9 log copies/ml (median, 5.56 log/ml) and fluctuated slightly during the follow-up. Median HCV RNA levels did not significantly differ among infants, children, and adolescents. Viral load was also independent of sex, route of infection, clinical manifestation, alanine aminotransferase levels, and liver histology. All 11 perinatally infected children became chronic HCV carriers, whatever their initial viral load; retrospective testing of sera taken in the first day of life in three infants showed high viremia levels. CONCLUSIONS: Viremia levels observed in children were similar to those reported in adults, were independent of age, biochemical activity of liver disease, and chronicity of infection. They were also relatively stable, suggesting that serial measurement of viral load is useless in untreated infants and children. The detection of viremia at birth in children in whom chronic hepatitis developed later suggests the possibility of in utero infection.