Phenotypic variability in Bartter syndrome type I.

Limited phenotypic variability has been reported in patients with Bartter syndrome type I, with mutations in the Na-K-2Cl cotransporter gene (BSC). The diagnosis of this hereditary renal tubular disorder is usually made in the antenatal-neonatal period, due to the presence of polyhydramnios, premature delivery, hypokalemia, metabolic alkalosis, hypercalciuria, and nephrocalcinosis. Among nine children with hypercalciuria and nephrocalcinosis, we identified new mutations consistent with a loss of function of the mutant allele of the BSC gene in five. Three of the five cases with BSC gene mutations were unusual due to the absence of hypokalemia and metabolic alkalosis in the first years of life. The diagnosis of incomplete distal renal tubular acidosis was considered before molecular evaluation. Three additional patients with hypokalemia and hypercalciuria, but without nephrocalcinosis in the first two and with metabolic acidosis instead of alkalosis in the third, were studied. Two demonstrated the same missense mutation A555T in the BSC gene as one patient of the previous group, suggesting a single common ancestor. The third patient presented with severe hypernatremia and hyperchloremia for about 2 months, and a diagnosis of nephrogenic diabetes insipidus was hypothesized until the diagnosis of Bartter syndrome type I was established by molecular evaluation. We conclude that in some patients with Bartter syndrome type I, hypokalemia and/or metabolic alkalosis may be absent in the first years of life and persistent metabolic acidosis or hypernatremia and hyperchloremia may also be present. Molecular evaluation can definitely establish the diagnosis of atypical cases of this complex hereditary tubular disorder, which, in our experience, may exhibit phenotypic variability.

[The role of liver in muscular dystrophy]. / Il ruolo del fegato nella distrofia muscolare.

Epidemiological or anamnestical data may either help or confuse the differential diagnosis of various diseases mainly characterized by asymptomatic hypertransaminasemia. Occasional finding of transaminase elevation may lead to suppose chronic or persistent hepatopathy, particularly when the patient seems to be asymptomatic and presents anamnestic data suggesting intoxication, acquired infection from blood derivatives, origin from geographic areas with high prevalence of viral hepatitis. However, the true existence of hepatic damage, concurrent to a myopathy, may be also related to the primitive diseases. There is evidence, in fact, that in the presence of muscular dystrophy, a disease caused by structural defects of muscular membranes, also hepatocytes show ultrastructural defects. The present work reports the cases of 5 children, hospitalized at the 1st Clinic of Infectious Diseases of the University of Genoa, affected by persistent hypertransaminasemia and showing anamnestical data suggesting hepatitis; histological findings of hepatitis were effectively shown in 3 patients after needle biopsy. All patients proved to be affected by muscular dystrophy. Hepatic damage results cannot be correlated to known causes of hepatopathy. During disease courses heralded by asthenia and hypertransaminasemia, differential diagnosis must take into account non-hepatic diseases, like muscular dystrophy. Although this disease mainly affects the muscle, also the liver seems to be involved, as suggested by histological changes found in some patients.

HBV-DNA-related hepatocellular carcinoma occurring in childhood. Report of three cases.

In a series of 325 HBV chronically infected children observed over an 18-year period, three developed HCC. These three children were born in southern Italy, a region characterized by a high endemic HBV infection rate; each had been infected perinatally, developed an acute hepatitis, and became a chronic carrier. Two of the three with cirrhosis were HBsAg positive at the time their HCC was detected. The remaining case had seroconverted to HBsAb but HBV-DNA integration could be demonstrated in the absence of cirrhosis; moreover HBV antigens were not expressed in the tissue of this case. The interval between HBV infection and HCC appearance in these three cases ranged from six to 11 years. A similarity between these three Italian cases and the majority of HCC arising in chronically infected children in the Far East is noted.

[Liver cirrhosis in childhood. Considerations on 22 cases with different etiology]. / La cirrosi epatica in età pediatrica. Considerazioni su ventidue casi a differente eziologia.

Although rather uncommon and multifactorial in etiology, liver cirrhosis is a severe and often rapidly fatal disease in pediatrics. In our institution, during the last 15 years, 22 children with liver cirrhosis have been followed. The underlying predisposing condition was HBV infection (8 cases), CMV perinatal infection (2 cases), Wilson's disease (4 cases), chronic cholestasis (2 cases) and alcohol abuse (2 cases); in 4 cases no predisposing condition was evident. In all cases the histological examination of the liver was the diagnostic cornerstone. The mean age at diagnosis was 6 years and 8 months, with an early onset especially in the posthepatitis cirrhosis. In 10 out of 22 patients, cirrhosis was not preceded by an history of chronic liver disease. Poor subjective symptomatology was present in 13 of the cases, hepatomegaly in all, splenomegaly in 18 cases, signs of hepatic failure in 13 cases. In all patients various impairments of hepatocellular synthesis were detectable, especially during the period preceding the development of hepatic insufficiency. The mean time to cirrhosis was 5 years. The average duration of the follow up was 3 years and 4 months: during the follow up 6 patients improved, 5 patients showed no clinical or functional modifications of their hepatic disease, 3 patients worsened and 8 died. In order to perform suitable treatment of liver cirrhosis the need of early diagnosis and etiological definition should be emphasized.

[Anatomo-histopathological and immunological correlations in chronic hepatitis]. / Correlazioni anatomo-istopatologiche ed immunologiche nell'epatite cronica.

An immunohistological survey was made of cryostat liver sections from 30 patients: 17 adults and 13 children affected by chronic hepatitis were studied. Immunofluorescent techniques were used to determine the following: HBsAg, HBcAg, HDV, IgG, serum antibodies, B lymphocytes and CD4+, CD8+ and activated T lymphocytes. The tissue antibody response and the inflammatory infiltrate was more evident in CAH than in CPH. The prevalent cell subpopulation in HBV hepatitis is represented by CD8+ while in non-A non-B and autoimmune forms by CD4+. Furthermore, in histologically more serious forms 75% of the T cells were activated with respect to 25% in non active forms. The difference was statistically significant.

[Reactivation of virus replication during immunosuppressive therapy in children with chronic hepatitis B]. / Riattivazione della replicazione virale in corso di terapia immunosoppressiva in bambini affetti da epatite cronica tipo B.

The aim of the present work is to assess whether reactivation of viral replication occurred in children affected by chronic hepatitis undergoing long term immunosuppressive therapy. 123 serum samples belonging to 25 children were retrospectively evaluated for HBV-DNA and HBeAg. Sera were collected prior to and during the protocol treatment (steroids alone or with azathioprine). Presence of HBV-DNA was evaluated by means of molecular hybridization technique, using a radiolabelled probe of cloned HBV-DNA. Sera (100 1) were denatured and transferred into nylon membrane (spot) then prehybridized and hybridized. After washing in stringent conditions, the filter was exposed in autoradiographic cassette with Kodak film XOmat5. Positivity was semiquantitatively evaluated by blackening of the spot. Increase or appearance of HBV-DNA was observed in the sera from 24/25 pts. HBeAg became positive in 4/5 pts previously negative. Obtained data shows reactivation of viral replication during immunosuppressive therapy. Data are especially significant in those cases in which such activity has apparently ceased or not been detected; HBV may be considered as a latent virus.

Treatment of children with chronic hepatitis B with a combination of steroids and human lymphoblastoid interferon.

The efficacy of human lymphoblastoid interferon (Wellferon) therapy was measured in 20 children with chronic hepatitis B with or without pretreatment with prednisolone. Patients were randomised to receive 0.6 mg/kg/day prednisolone for 3 weeks, then at 0.3 mg/kg for a fourth week or placebo. All patients then received interferon 5 MU/m2 i.m. for 12 weeks; daily for 5 days then three times a week for the remaining 11 weeks. Preliminary results show that 25% of children had a permanent loss of viral markers of replication. However, response to interferon varied widely between individuals and a prolonged follow-up is required in order to determine the influence of prednisolone pretreatment on the efficacy of interferon therapy.

Hepatitis B virus (HBV)-DNA-positive hepatocellular carcinoma following hepatitis B virus infection in a child.

Integrated hepatitis B virus (HBV) DNA sequences were found in neoplastic liver tissue of a hepatitis B surface antigen (HBsAg)-negative child who had previously suffered from HBsAg-positive chronic active hepatitis and was anti-HBs and anti-hepatitis B core (HBc) positive at the time of tumor development. Reintegration pattern was consistent with the presence of a single integration site of the HBV genome into cellular DNA, and clonal proliferation of such infected cells. A normal liver, tested in the same experiment with the same amount of total DNA, was negative for viral DNA sequences. These findings support the possible oncogenic role of HBV in the development of liver cancer, not only in adults, but also in children, even in patients who are negative for HBsAg at the time of tumor diagnosis.

Correlation between e/anti e system and evolution of B virus chronic hepatitis in pediatric patients.

The authors have performed a longitudinal study of 118 children affected with B virus chronic hepatitis. Our first observation revealed 92 children with HBeAg positive (26 CPH, 66 CAH), 22 children with anti HBe positive (6CPH, 15 CAH, 1 cirrhosis), 4 children (CAH) with e/anti-e negative. A correlation between the severity of clinical forms and the behaviour of the e/anti-e system was not observed. Seroconversion was observed during the follow up period in 37 of 92 subjects in an average time of 59.83 +/- 32 months, time rather prolonged in patients under immunosuppressive therapy. To compare the clinical progress and the evolution of CPH and CAH respectively, always with regard to the e/anti-e system, statistically significant differences did not result. Only anti HBe positive recovered subjects, inclusive of seroconverted patients and those anti HBe from the first observation, showed significant results to the statistical analysis. Still, seroconversion corresponds frequently to a stable improvement of hepatitis. On the contrary evolution into cirrhosis was observed in 5 patients that had anti HBe antibodies.

Infection with the delta agent in children.

Serological evidence of infection with the hepatitis B virus associated delta agent (delta) was found in 34 of 270 Italian children with HBsAg-positive liver disease. In different histological forms of chronic HBsAg hepatitis the prevalence of delta infection increased in parallel with the activity of the disease and was maximal in children with cirrhosis. During two to seven years of follow up the hepatitis deteriorated in 38% of the 34 patients with delta infection and ameliorated only in 9%. By contrast the disease usually ran a mild course in the 236 delta-negative carriers of HBsAg, with remission in 55% of these children and deterioration in only 7%. The outcome of chronic hepatitis associated with delta infection was not influenced by treatment with steroids and azathioprine. Chronic delta infection in children is usually accompanied by serious liver disease, that has a tendency to progress and is unresponsive to conventional immunosuppressive treatment.