Natural history and clinical features of hepatitis C virus infection during childhood: A nationwide, observational survey in Japan.

AIM: Few data on spontaneous clearance rates of cases of mother-to-child transmission of hepatitis C viral (HCV) infection are available in Japan. Furthermore, the treatment courses of interferon-based and direct-acting antiviral agent (DAA) therapies for children are also unclear. Our aim was thus to clarify the long-term natural progression of HCV infection and the treatment outcomes of children in Japan. METHODS: We conducted a combined multicenter, observational survey involving 65 pediatric institutions in Japan. Pediatric HCV infection cases with patients born between 1973 and 2021 were collected over the 11-year period from 2012 to 2022. A total of 563 patients were enrolled, with 190 excluded for having insufficient laboratory data or treatment information, resulting in 373 eligible cases. RESULTS: Of 328 cases of mother-to-child infection, 34 (10.4%) had spontaneous clearance, with a median time to spontaneous clearance of 3.1 years (range 0.9-7.2 years). Of the total 373 eligible cases, 190 received antiviral therapy (interferon-based therapy, 158; DAA therapy, 32). Sustained virologic response rates after first-line treatment were 75.3% (119/158) and 100% (32/32) for interferon-based therapy and DAA therapy, respectively, with the DAA group showing a shorter time from therapy initiation to viral negativity (2.7 vs. 1.0 months; p = 0.0031). CONCLUSIONS: Approximately 10% of Japanese children infected by mother-to-child transmission achieve spontaneous resolution of HCV infection. Our findings indicate that DAA therapy is safe and highly effective in Japanese children, achieving higher sustained virologic response rates and shorter time to clearance of the virus compared with interferon-based therapy.

Serum Zinc and Selenium in Children with Inflammatory Bowel Disease: A Multicenter Study in Japan.

BACKGROUND: Reports of zinc and selenium deficiencies accompanying inflammatory bowel disease (IBD) mostly have originated from Western countries and concerned adult patients. Whether Japanese children with IBD have similar deficiencies remained unclear. AIM: We aimed to elucidate differences in serum zinc and selenium concentrations in Japanese children between types of IBD. METHODS: Children under 17 years old undergoing care at 12 Japanese pediatric centers were retrospectively enrolled between November 2016 and February 2018 to 3 groups representing Crohn's disease (CD), ulcerative colitis (UC), and normal controls (NC) with irritable bowel syndrome or no illnesses. Serum zinc and selenium were measured by atomic absorption spectrophotometry. Zinc and selenium deficiencies were defined by serum concentrations < 70 µg/dL and < 9.5 µg/dL, respectively. RESULTS: Subjects included 98 patients with CD (median age, 13 years), 118 with UC (11 years), and 43 NC (11 years). Serum zinc and selenium were significantly lower in CD (median, 64 and 12.6 µg/dL respectively) than in UC (69 and 14.6; P < 0.05 and P < 0.001) or NC (77 and 15.7; P < 0.01 and P < 0.001). Zinc deficiency was significantly more prevalent in CD (60.2%) than in NC (37.2%; P < 0.05), but not than in UC (51.7%; P = 0.22). Selenium deficiency was significantly more prevalent in CD (15.3%) than in UC (5.9%; P < 0.05) or NC (0%; P < 0.01). CONCLUSIONS: In Japanese children under 17 years old, serum zinc and selenium were significantly lower in CD than in UC or NC. Zinc and selenium should be monitored, and supplemented when deficient, in children with IBD, especially CD.

Clinical practice guidelines for the management of children with mother-to-child transmitted hepatitis C virus infection.

BACKGROUND: The first guidelines for care of pregnant women carrying the hepatitis C virus (HCV) and their infants were published in 2005 in Japan. Since then, evidence has gradually accumulated worldwide regarding the natural course and treatment of this condition and, especially in recent years, treatment for chronic hepatitis C in adult patients has made great progress. However, the clinical practice policy for children has not been standardized, and new clinical practice guidelines for children with mother-to-child (MTC) transmitted HCV infection have become necessary. METHODS: In the development of the current guideline, we requested cooperation from The Japanese Society for Pediatric Infectious Diseases, The Japan Society of Hepatology, and the Japan Society of Obstetrics and Gynecology. The committee members were recommended and approved by each society to participate in developing the guidelines. The guideline was also created in accordance with the Minds Guide for Practice Guideline Development. The statements were prepared by consensus-building using the Delphi method, based on the comprehensively searched academic papers and guidelines. These articles were retrieved through searching the PubMed, Cochrane Library, and the Igaku Chuo Zasshi databases. RESULTS: Eight clinical questions (CQs) with clinical statements were developed regarding etiology (CQs 1-3), diagnosis (CQs 4 and 5), and treatment (two CQs 6 and 7). In each statement, the consensus rate, evidence level, and recommendation level were determined. CONCLUSION: The guidelines will be helpful in the management of children with hepatitis C MTC transmission.

Very early-onset inflammatory bowel disease in Japan: A nationwide survey.

BACKGROUND AND AIM: Very early-onset inflammatory bowel disease is defined as inflammatory bowel disease diagnosed before 6 years of age. Very early-onset inflammatory bowel disease has various differential diagnoses, including primary immunodeficiency disorders, and is known to be resistant to conventional treatment. Therefore, global attention is required to manage this challenging condition. We conducted a retrospective epidemiological survey of the number of patients, final diagnosis, and examinations performed to diagnose very early-onset inflammatory bowel disease in Japan. METHODS: A primary questionnaire about the number of very early-onset bowel disease cases and its diagnosis was administered to 630 pediatric facilities nationwide in Japan. A secondary survey about the examinations performed to achieve diagnosis was sent to the facilities that responded to the first survey. RESULTS: The answering rate was 92.2% (581/630 facilities); 81 facilities had 225 very early-onset bowel disease patients undergoing their care during the past 68 months. Twenty-six patients (11.6%) were diagnosed with immunodeficiency-associated inflammatory bowel disease. The answering rate of the secondary survey was 70.4% (57/81 facilities). Colonoscopy, esophagogastroduodenoscopy, and small bowel imaging were performed for 99.4%, 67.5%, and 28.8% of patients, respectively. Genetic analysis was performed for 26.9% (43/160 patients) of patients, and 51.2% (22/43) of patients were diagnosed with immunodeficiency-associated inflammatory bowel disease. CONCLUSIONS: Approximately 40 patients are diagnosed yearly in Japan. Imaging studies, especially for small bowel lesions, can be challenging for this unique group of patients. However, a comprehensive approach including immunological and genetic analyses appears useful for diagnosing immunodeficiency-associated inflammatory bowel disease.

Diagnostic accuracy of serum proteinase 3 antineutrophil cytoplasmic antibodies in children with ulcerative colitis.

BACKGROUND AND AIM: Serologic markers such as myeloperoxidase (MPO) antineutrophil cytoplasmic antibodies (ANCA) (MPO-ANCA) have been used to screen patients for ulcerative colitis (UC). However, MPO-ANCA shows limited accuracy in Asians. Proteinase 3 ANCA (PR3-ANCA) has performed better at UC diagnosis in Japanese adults than MPO-ANCA. The present study aimed to evaluate usefulness of PR3-ANCA for diagnosis of UC in Japanese pediatric practice. METHODS: Patients under 17 years old undergoing assessment at 12 Japanese pediatric centers between November 2016 and February 2018 were prospectively enrolled and divided into groups with UC, Crohn's disease (CD), intestinal disease control (IC), and healthy control (HC). Serum PR3-ANCA and MPO-ANCA were analyzed using chemiluminescence enzyme immunoassay kits. RESULTS: Sera from 367 patients (148 with UC at a median age of 12 years; 120 with CD, 13 years; 56 with IC, 10.5 years; and 43 with HC, 10 years) were examined. Median PR3-ANCA values in UC (1.6 U/mL) were greater than in CD (0.2; P < 0.001), IC (0.15; P < 0.001), and HC (0.1; P < 0.001). In receiver operating characteristic curve analyses, the area under the curve for PR3-ANCA was 0.79, significantly greater than for MPO-ANCA (0.58; P < 0.001). Using a cut-off value of 0.8 U/mL determined from the receiver operating characteristic analyses, PR3-ANCA showed significantly greater sensitivity (64.9%) than MPO-ANCA (cut-off, 0.2 U/mL; sensitivity, 19.6%; P < 0.001) and good specificity (83.6%). CONCLUSIONS: In Japanese children and adolescents, PR3-ANCA performed better as a serologic marker for diagnosis of UC than MPO-ANCA. To our knowledge, this is the first report of such a comparison.

Transitional care for inflammatory bowel disease: A survey of Japanese pediatric gastroenterologists.

BACKGROUND: In 2019 we reported the results of a Japanese national survey designed to explore the views of adult gastroenterologists regarding transitional care for patients with childhood-onset inflammatory bowel disease (IBD). For the present study, we conducted a similar survey of pediatric gastroenterologists to compare the views of the two sets of specialists. METHODS: The survey conducted in 2019 involved 48 representative members of the Japanese Society for Pediatric Gastroenterology, Hepatology and Nutrition. They were contacted by conventional mail and their answers were not anonymized. Respondents who had already referred patients with IBD to adult gastroenterologists were asked in a questionnaire to rank the importance of specific statements on a Likert scale. RESULTS: The response rate was 79% and 29 (60%) of the respondents had experienced transitional care for patients with IBD. Transfer to adult care was considered by 90% of the respondents to be the ideal form of medical care for adolescents/young adults with IBD. However, 59% of the respondents had experienced some degree of difficulty when making referrals for such care. The majority of pediatric gastroenterologists considered that the ideal age for transfer was 18-22 years. Among the respondents, physicians at municipal hospitals considered that the presence of diseases other than IBD and a shortage of manpower were significantly more important issues than other practice settings. CONCLUSIONS: The present survey revealed that the general views regarding transitional care for IBD between pediatric and adult gastroenterologists were similar, except for the appropriate time for transfer. The results underline the importance of preparing a transition program appropriate to practice settings.

Hepatitis B virus-related hepatocellular carcinoma in young adults: Efficacy of nationwide selective vaccination.

AIM: Hepatitis B vaccination in infancy was carried out in Japan only when the mother was persistently infected from 1986 to 2016. The aim of the present study was to elucidate the results of vaccination for the prevention of hepatocellular carcinoma in young adults. METHODS: We studied the number of patients who had liver cancer and died from 1976 to 2017 using a national database. Furthermore, we carried out a nationwide survey focusing on patients with hepatitis B virus-related hepatocellular carcinoma who were diagnosed when aged <40 years from 2007 to 2016. RESULTS: The national database showed that the number of deaths of patients aged <40 years decreased from 337 in 1986 to 61 in 2016. Among the 122 patients with hepatocellular carcinoma (HCC) who were registered in the survey, just three patients were born after the start of the vaccination in 1986. Liver cirrhosis, defined by a high Fib-4 index (≥3.25), was found in just 12.5% of the patients at the time of the survey. HCC was incidentally diagnosed in 85 of the 122 (69%) patients. More than 60% of the patients (54/88) were dead at the time of the study, which may be attributed to the delay in diagnosis. CONCLUSIONS: Selective vaccination was effective for the prevention of hepatitis B virus-related HCC. In contrast, many young adults who missed the chance of hepatitis B vaccination and HCC surveillance developed HCC and died. Hepatitis B virus screening in young adults and careful follow up of infected patients are important to prevent HCC development.

Infliximab for pediatric patients with ulcerative colitis: a phase 3, open-label, uncontrolled, multicenter trial in Japan.

BACKGROUND: Pediatric ulcerative colitis (UC) is typically more extensive and has a more active disease course than adult UC, and requires early treatment augmentation to achieve and maintain disease remission. The present study aimed to investigate the efficacy, safety, and pharmacokinetic profile of infliximab (IFX) in pediatric patients with moderate-to-severe UC and inadequate response to existing treatment. METHODS: This open-label, uncontrolled, multicenter, Phase 3 trial was conducted at 17 centers in Japan between April 2012 and September 2014. Pediatric patients (aged 6-17 years) diagnosed with moderate-to-severe UC received a treatment protocol comprising 5 mg/kg IFX at Weeks 0, 2, and 6, and Clinical Activity Index (CAI)-based responders at Week 8 also received treatment at 8-week intervals at Weeks 14 and 22, with a final evaluation at Week 30. RESULTS: A total of 21 patients were treated in this study. IFX therapy rapidly improved clinical symptoms, and this effect was maintained for up to 30 weeks. Overall CAI-based remission rate was 42.9% and overall Pediatric Ulcerative Colitis Activity Index (PUCAI)-based remission rate was 19.0%. Median partial Mayo score was 6.0 at baseline and 4.0 at Week 30 (overall). Among the eight patients who underwent sigmoidoscopy, Mayo response was achieved at Week 30 (overall) in three patients (37.5%). Trough serum IFX concentrations in Week 8 CAI-based responders were maintained throughout the study period. Adverse events and serious adverse events were observed in 95.2 and 14.3% of patients, respectively. CONCLUSIONS: These results support the use of IFX in the treatment of pediatric patients with UC with inadequate response to existing treatment. TRIAL REGISTRATION: ClinicalTrials.gov, registration number: NCT01585155 .

Adult gastroenterologists' views on transitional care: Results from a survey.

BACKGROUND: In 2018, Japanese guidelines for autonomy support of patients with inflammatory bowel disease (IBD) in the transitional period were published. These guidelines, however, were prepared mainly by pediatric gastroenterologists. In order to improve such supportive guidelines, it is necessary for pediatric gastroenterologists to be aware of the attitudes and expectations of adult gastroenterologists. Accordingly, the first Japanese national survey designed to explore the views of adult gastroenterologists regarding successful transitional care was conducted. METHODS: The survey involved institutions at which adult gastroenterologists in the Ministry of Health, Labor and Welfare of Japan's Inflammatory Bowel Diseases Study Group, were working. Physicians were contacted by conventional mail, and their answers were not anonymized. A total of 100 eligible adult institutions were identified. Further specific subgroup analysis was conducted. RESULTS: A response rate of 34% was achieved. Seventy-six percent of the respondents had experienced some degree of difficulty when accepting patients with childhood-onset IBD referred from pediatric gastroenterologists. With regard to the ideal form of medical care for adolescent patients with IBD, transfer to adult care was supported by 94% of the respondents. Only 27% of respondents, however, stated they would have no hesitation in accepting patients referred from pediatric care centers. Two crucial areas requiring improvement were identified: inadequate clinical summaries and lack of patient independence from their parents/caregivers. CONCLUSIONS: The present survey results reinforce the importance of a transitional program of education for childhood-onset IBD patients and the need to improve communication between adult and pediatric gastroenterologists.

Suppression of hepatitis B surface antigen production by combination therapy with nucleotide analogues and interferon in children with genotype C hepatitis B virus infection.

AIM: Sustained suppression of hepatitis B surface antigen (HBsAg) production after interferon (IFN) treatment has not been reported for children with genotype C chronic hepatitis B virus (HBV) infection, which is prevalent in Asia. Among children with hepatitis B envelope antigen-positive genotype C chronic HBV infection, we compared the efficacy of combination therapy with nucleotide analogues and IFN-α in 11 children with 12 historical cases treated with IFN monotherapy. METHODS: The combination of lamivudine and conventional IFN-α was introduced for the first three patients; the other eight patients were treated with entecavir and pegylated IFN. RESULTS: Demographic factors as well as baseline HBsAg titers and HBV-DNA levels were similar between the two groups. In the combination therapy group, viral loads were suppressed in 9/11 to below 4.0 log copies/mL both at the end of the therapy (EOT) and at 6 months after EOT. In contrast, in the IFN monotherapy group, suppression of viral loads was observed in 2/12 and 3/12 at EOT and at 6 months after EOT, respectively. In the combination therapy group, HBsAg titers dropped from 4.03 at pretreatment to 2.91 log IU/mL at 6 months after EOT with 4/11 showing a drop to below 1000 IU/mL (one patient achieved HBsAg clearance). In contrast, the amount of HBsAg did not change during the corresponding periods in the IFN monotherapy group. CONCLUSIONS: Our preliminary results suggest that combination therapy might be effective in the suppression of HBsAg production as well as HBV-DNA production for children with genotype C chronic HBV infection.

Favorable response to immunosuppressive combination therapy with mizoribine and azathioprine in children with primary sclerosing cholangitis.

Primary sclerosing cholangitis (PSC), with no curative intervention, can progress to end-stage liver disease. Mizoribine, a purine antimetabolite, has never been used for the management of PSC. To evaluate the role of mizoribine with azathioprine we undertook a preliminary clinical study in children with PSC. Children with PSC and autoimmune features were simultaneously treated with mizoribine and azathioprine. Ursodeoxycholic acid or mesalazine were not regulated. The primary end-points of our study included improvement of aspartate aminotransferase, alanine aminotransferase, and γ-glutamyltransferase. Liver histology, immunostaining studies of the liver, and magnetic resonance cholangiopancreatography (MRCP) were also assessed. We have treated four PSC children: two treatment-naïve patients (cases 1 and 2), and two with established liver cirrhosis (cases 3 and 4). Both case 1 and 2 showed a normalization of liver enzymes and case 2 showed an improvement in MRCP findings. Cases 3 and 4 also showed an improvement in varices, MRCP findings, and liver histology. The combination therapy may be effective for some children with PSC and autoimmune features. By ameliorating both parenchymal inflammation and cholangiopathy of PSC, the therapy might improve the prognosis for patients. It awaits further prospective studies to confirm the efficacy of this therapy in patients with PSC.

Interferon-based Simeprevir Therapy for Pediatric Patients with Chronic Hepatitis C Viral Infection.

Interferon-based simeprevir therapy showed high efficacy and tolerability in children with genotype 1 hepatitis C virus infection. While direct-acting antivirals (DAAs) therapy are undergoing study in children, this regimen is considered an available therapeutic option for selected patients in countries where DAAs have not yet been approved.

Antiviral therapy for hepatitis B virus during second pregnancies.

Mother-to-child transmission of the hepatitis B virus (HBV) is a major concern for infected mothers, especially after their first child has become an HBV carrier despite immunoprophylaxis. Eight mothers whose first child had become an HBV carrier despite immunoprophylaxis were referred for antiviral therapy during the subsequent pregnancy. All pregnant women were seropositive for both the hepatitis B surface antigen and hepatitis B e antigen. In the treatment group (three receiving lamivudine and two receiving tenofovir), mother-to-child transmission of the HBV was successfully prevented in all infants (5/5). On the other hand, two of three infants became HBV carriers in the untreated group. There were no significant adverse effects in either mothers or infants. Antiviral therapy using lamivudine and tenofovir during the second pregnancy successfully prevented mother-to-child transmission of the HBV for high-risk mothers.

Treatment with infliximab for pediatric Crohn's disease: Nationwide survey of Japan.

BACKGROUND AND AIM: Childhood-onset inflammatory bowel disease (IBD) is characterized by extensive intestinal involvement and rapid early progression. Infliximab (IFX), cyclosporin (CYA), and tacrolimus (FK506) are increasingly used to treat pediatric IBD; however, their long-term effects and adverse events have not been properly investigated in pediatric patients. The aim of this study was to characterize the effects of these biologics and immunomodulators on pediatric IBD patients in Japan. Additionally, we assessed IFX use in pediatric patients with Crohn's disease (CD). METHODS: A national survey of IFX, adalimumab, CYA, and FK506 use in pediatric IBD patients (< 17 years of age) was sent to 683 facilities in Japan from December 2012 to March 2013. Secondary questionnaires were sent to pediatric and adult practitioners with the aim of assessing the effectiveness and safety of IFX for pediatric CD patients. RESULTS: The response rate for the primary survey was 61.2% (N  =  418). Among 871 pediatric CD patients, 284 (31.5%), 24, 4, and 15 received IFX (31.5%), adalimumab, CYA, and FK506, respectively, from 2000 to 2012. According to the secondary survey, extensive colitis (L3, Paris classification) was diagnosed in 69.4% of pediatric CD patients who received IFX. Regarding the effectiveness of IFX in this population, 54.7% (99/181) of patients were in remission, and 42.0% (76/181) were on maintenance therapy. However, 32.0% (58/181) of patients experienced adverse events, and one patient died of septic shock. CONCLUSIONS: Infliximab is reasonably safe and effective in pediatric CD patients and should therefore be administered in refractory cases.

Peginterferon Therapy in Children With Chronic Hepatitis C: A Nationwide, Multicenter Study in Japan, 2004-2013.

OBJECTIVES: The aim of the present study was to review the medical treatment of Japanese children and adolescents with chronic hepatitis C in the past 10 years. METHODS: This nationwide, multicenter study evaluated patients who were younger than 18 years of age when diagnosed with chronic hepatitis C virus (HCV) infection and were treated with pegylated interferon (PEG-IFN) monotherapy or PEG-IFN/ribavirin (RBV) combination therapy between 2004 and 2013. The subjects' median age was 10 (3-18) years, with a male to female ratio of 52:50 and a genotype-1 to genotype-2 ratio of 45:57. Among the 102 patients, 18 received PEG-IFN monotherapy and 84 received PEG-IFN/RBV combination therapy. The IL28B genotype polymorphism was analyzed in patients infected with genotype-1. RESULTS: In patients with HCV genotype-1 infections, sustained virological response (SVR) rates obtained by PEG-IFN monotherapy and by PEG-IFN/RBV combination therapy were 100% (2/2) and 72% (31/43), respectively. In patients with HCV genotype-2 infections, SVRs were 75% (12/16) and 100% (41/41), respectively. In 32 genotype-1 patients available for the IL28B genotype (rs8099917), SVR was achieved in more patients in the IL28B major allele group than in the minor allele group (15/17 vs 7/15, P = 0.021) after PEG-IFN/RBV combination therapy. The frequencies of adverse events were similar between the treatment regimens. CONCLUSIONS: Overall, both therapies showed encouraging results, and were reasonably safe in children and adolescents with chronic hepatitis C. The IL28B genotype was useful for predicting the treatment response to PEG-IFN/RBV combination therapy in this cohort.

Natural history of chronic hepatitis B virus infection in childhood and efficacy of interferon therapy.

OBJECTIVES: In short-term observations, interferon (IFN) therapy has been shown to be effective in producing both biochemical and virological responses in children with chronic hepatitis B virus (HBV) infection. However, in long-term follow up, no studies have shown a clear advantage of IFN therapy during childhood. We conducted a retrospective study on the sustained effect of IFN therapy among a Japanese pediatric population. METHODS AND SUBJECTS: A retrospective study was performed on 155 children with chronic HBV infection who were followed in two affiliated hospitals during the period from 1986 to 2013. RESULTS: The 155 patients comprised 97 males and 58 female. Infection route was maternal transmission in 96/155 patients. HBV genotype was A in 17, B in 6, and C in 51 patients. IFN therapy was performed in 48 patients. One year after the completion of IFN therapy, normalization of alanine aminotransferase (ALT) and lower viral levels (<10(4) copies/ml) was observed in 43 and 29 patients, respectively. The sustained effects of IFN therapy were evaluated by comparison between 43 hepatitis B e-antigen (HBeAg)-positive patients treated with IFN and 67 patients with chronic hepatitis B observed without IFN therapy. A Cox's proportional hazard analysis showed a higher seroconversion rate in the IFN group than in the untreated group (p = 0.003). Similarly, there were higher rates of ALT normalization and lower viral levels in the IFN group than in the untreated group (p = 0.001 for both). CONCLUSION: IFN therapy showed sustained effects for achieving ALT normalization and HBeAg seroconversion and for reducing the viral load in children with chronic hepatitis B.

Transmission route and genotype of chronic hepatitis B virus infection in children in Japan between 1976 and 2010: A retrospective, multicenter study.

AIM: The aim of this study was to clarify the trends of the infectious source of chronic hepatitis B virus (HBV) infection and the HBV genotype in the Japanese pediatric population over the last three decades. METHODS: The present study was a retrospective, nationwide, multicenter study. Patients who were under 20 years of age when diagnosed with chronic HBV infection were eligible for enrollment in this study. A total of 430 patients (male/female, 256/174; age at the time of writing, 1-37 years; median age, 14 years; birth year, 1976-2010) from 11 hospitals were evaluated. RESULTS: The incidence of chronic HBV infection from 1976 to 1980, 1981-1985, 1986-1990, 1991-1995, 1996-2000, 2001-2005 and 2006-2010 was 56, 52, 34, 37, 81, 92 and 78, respectively. Of the 430 patients, 304 (71%), 61 (14%), 11 (3%) and 54 (13%) were infected via mother-to-child transmission, close contact, blood transfusion and unknown source, respectively. After the introduction of perinatal immunoprophylaxis, the rate of mother-to-child transmission increased from 62% during the 1991-1995 period to 86% during the 2006-2010 period. The distributions of genotypes A, B, C, D and F were 3%, 9%, 86%, 2% and 1%, respectively. No obvious change was observed in the distribution of genotypes. Genotype C was significantly associated with mother-to-child transmission. CONCLUSION: Mother-to-child transmission remains the primary source of chronic HBV infection after the introduction of immunoprophylaxis. Taking measures to prevent immunoprophylaxis failure is essential to reduce pediatric chronic HBV infection in Japan.

Association of IL28B polymorphisms with virological response to peginterferon and ribavirin therapy in children and adolescents with chronic hepatitis C.

AIM: The objective of the current study was to find baseline predictive factors of response to therapy with pegylated interferon and ribavirin (PEG-IFN/RBV therapy) in children and adolescents with chronic hepatitis C. METHODS: IL28B genotype and mutations in the core of hepatitis C virus (HCV) were analyzed in 30 patients treated with PEG-IFN/RBV for HCV infection. The initial rate of decrease in the viral load was assessed during the first 2 weeks of treatment. RESULTS: IL28B major allele was seen more frequently in patients with sustained virologic response (SVR) than in non-SVR patients (P < 0.001). There was no difference between these two groups in frequency of Core 70 mutation. Among patients with genotype-1, SVR was achieved in more patients (P = 0.007) in the IL28B major allele group than in those in the minor allele group. The early decrements in the viral load (log/2 weeks) were 3.80 ± 0.86 in the genotype-2 major allele group, 1.82 ± 0.84 in the genotype-1 major allele group, and 0.41 ± 0.33 in the genotype-1 minor allele group. CONCLUSIONS: Among pediatric patients with HCV infection the effectiveness of PEG-IFN/RBV therapy may be lower in the group with genotype-1 IL28B minor alleles than in other groups with IL28B major allele. Treatment strategy should be carefully implemented in patients with IL28B unfavorable type.

[Evaluation of six cases with hypothalamic hamartoma: the relationship between MRI findings and clinical features].

OBJECTIVE: We evaluated the relationship between MRI findings and clinical features in patients with hypothalamic hamartoma (HH). METHODS: We retrospectively reviewed MRI and clinical data (mental retardation, precocious puberty, behavioral problems, and epilepsy) in six patients (3 males and 3 females, ages 12 to 26) with HH. Based on the MRI classification by Arita, HH was classified into two types: parahypothalamic (P) and intrahypothalamic (I). RESULTS: Only one patient was classified as having P-type HH and five were classified as having I-type HH. The patient with P-type HH (diameter 21 mm) showed precocious puberty and mild behavioral problems, but did not developed epilepsy. On the other hand, all patients with I-type HH (diameter 10-32 mm, median 17 mm) developed epilepsy and behavioral problems. Except for one patient, who had the smallest sized HH, I-type four patients developed mental retardation and precocious puberty. Among patients with I-type HH, the size of the tumor was inversely correlated with the age at epilepsy onset and with the degree of mental retardation (DQ/IQ). CONCLUSION: Our data suggested that the MRI classification by Arita, when combined with tumor size, might be helpful in predicting the clinical manifestations in patients with HH.

The burden of rotavirus gastroenteritis and hospital-acquired rotavirus gastroenteritis among children aged less than 6 years in Japan: a retrospective, multicenter epidemiological survey.

BACKGROUND: Rotavirus is a leading worldwide cause of acute gastroenteritis in young children. This retrospective hospital-based study assessed the burden of rotavirus gastroenteritis in children younger than 6 years in Japan. METHODS: Children admitted to eight hospitals for acute gastroenteritis between 2008 and 2009 were identified from hospital admission databases. Diagnosis of acute gastroenteritis/rotavirus gastroenteritis and hospital-acquired rotavirus gastroenteritis was confirmed based on either the International Classification of Diseases and Related Health Problems 10th revision (ICD10) codes (intestinal infectious diseases [AA00-AA09] and rotavirus gastroenteritis [A08.0]) or from rapid rotavirus diagnostic test results. RESULTS: Of 13,767 hospitalized children, 11.9% (1,644), 4.8% (665) and 0.6% (81) were diagnosed with acute gastroenteritis, rotavirus gastroenteritis and hospital-acquired rotavirus gastroenteritis, respectively. Among acute gastroenteritis hospitalizations, 40.5% (665/1,644; ICD10 and rapid test) and 57.7% (645/1,118; rapid test only) were confirmed as rotavirus positive. Of 1,563 children with community-acquired acute gastroenteritis, 584 (37.4%) cases were confirmed as rotavirus positive. The median durations of hospitalization for all and community-acquired rotavirus gastroenteritis were 5.0 days (range: 2.0-133.0 days) and 5.0 days (range: 2.0-34.0 days), respectively. Among rotavirus gastroenteritis hospitalizations, 12.2% (81/665) of cases were hospital-acquired and the median duration of hospitalization was 10.0 days (range: 2.0-133.0 days). The median duration of additional hospitalization due to hospital-acquired rotavirus gastroenteritis was 3.0 days (range: 0-14 days). The overall incidence rate of hospital-acquired rotavirus gastroenteritis was 1.0 per 1,000 children hospital-days. The number of rotavirus gastroenteritis cases peaked between February and May in both 2008 and 2009, and the highest number of cases was reported in March 2008 (21.8%; 145/665). The highest number of rotavirus gastroenteritis hospitalizations (24.1%; 160/665) was observed in children aged 12-18 months. The proportion of hospital-acquired rotavirus gastroenteritis was higher in children aged below 18 months as compared to children at least 18 months of age (0.94 [95% CI: 0.71-1.21] vs. 0.39 [95% CI: 0.25-0.58]) and for children hospitalized for at least 5 days compared to those hospitalized for less than 5 days (0.91 [95% CI: 0.72-1.14] vs. 0.15 [95% CI: 0.05-0.32]). CONCLUSIONS: Both community- and hospital-acquired rotavirus gastroenteritis are significant public health problems in Japan. Data from this study justify the need for the introduction and implementation of rotavirus vaccination in the Japanese national immunization program. TRIAL REGISTRATION: ClinicalTrials.gov, NCT01202201.