Mona El Raziky

AIM: To study the safety and efficacy of hepatitis A vaccine (HAV) in children with chronic liver disease of various etiologies.

METHODS: Eleven children with chronic liver disease and thirteen age- and sex-matched controls negative for HAV antibodies were vaccinated against hepatitis A after they gave their informed consent. Children with uncontrolled coagulopathy or signs of hepatic decompensation were excluded. The vaccine (Havrix: 720 ELISA units in 0.5 mL, from GlaxoSmithKline Biologicals) was given intramuscularly in the deltoid in 2 doses 6 mo apart. Children were tested for HAV antibodies one and six months after the 1st dose and one month after the 2nd dose. Total serum bilirubin, alanine aminotransferase (ALT), and aspartate aminotransferase (AST) were determined immediately before and after one month of the 1st dose of the vaccine.

RESULTS: Only 7 out of the 11 patients were positive for HAV antibodies after the 1st dose of the vaccine, as compared to 100% of the controls. One month after the 2nd dose, all patients tested were positive for HAV antibodies. No deterioration in liver functions of patients was noted after vaccination. No adverse events, immediate or late, were reported by the mothers after each dose of the vaccine.

CONCLUSION: Hepatitis A vaccine is both safe and effective in this small studied group of children with chronic liver disease. Given the high seroconversion rate, post-vaccination testing for HAV antibodies is not needed.

UNLABELLED: Substance P is the most powerful endogenous vasodilator peptide produced by the enteric nervous system and partly cleared by the liver. Failure of the diseased liver to metabolize a vasodilator substance may be responsible for the rebound increased plasma level of vasoconstrictor intestinal peptide.

AIM: To investigate the plasma level of Substance P and to study its relationship to aldosterone and plasma renin activity changes occurring in pediatric patients with chronic liver disease.

METHODS: Forty patients with chronic liver disease and 10 healthy children were tested for AST, ALT, total and direct bilirubin, creatinine, aldosterone, plasma renin activity and plasma level of Substance P.

RESULTS: The plasma level of Substance P was increased in all patients with chronic liver disease (119.5+/-68.2 pg/ml) compared to controls (16.2+/-4.6 pg/ml). The aldosterone concentration and plasma renin activity were significantly higher in patients [(84.1+/-38.3 ng/dl) and (11.1+/-7.3 ng/ml/h)] than controls [(8.2+/-3.9 ng/dl) and (2.0+/-1.1 ng/ml/h)]. The highest level of Substance P and aldosterone were observed in glycogen storage disease patients.

CONCLUSION: Substance P was found to be increased in chronic liver disease patients; this increase was accompanied by an increase of aldosterone and plasma rennin activity. This correlation raises its potential use as a prognostic marker in chronic liver diseases.

The outcome of hepatitis C virus (HCV) infection acquired in childhood is uncertain because of the diversity of the epidemiological and clinical features of infection and disease. The aim of this study was to determine the outcome of HCV infection in 105 Egyptian children who tested positive for HCV antibody (anti-HCV). The data of 105 anti-HCV-positive children presenting to the Pediatric Hepatology Unit, Cairo University Children's Hospital, between 1995 and 2002, were retrospectively analysed for risk factors. Seventy-four children with available polymerase chain reaction results were further analysed clinically, serologically and histologically. The age range was 1.3-22 years, with a mean of 11.2 +/- 4.9 years. History of blood transfusion was found in 81 children (77%). HCV RNA was detected in 58.1% of 74 children. Persistently elevated alanine aminotransferase (ALT) levels were present in 40 patients (54.1%). Hepatitis B virus markers (HBsAg and/or anti-HBc) were detected in 18 patients (24.3%). Twenty-six of the 43 HCV RNA-positive children underwent a diagnostic liver biopsy that showed chronic hepatitis in 19 patients (73.1%), cirrhosis in one case only (3.8%), and normal biopsy findings in seven children (26.9%). Blood transfusion remains a major risk of HCV transmission among Egyptian children. HCV infection is not always benign in the childhood period. ALT levels remain elevated in half of the children and histological abnormalities are detected in three quarters of HCV RNA-positive cases.

No identifiable cause can be found in more than half of the cases of portal vein thrombosis (PVT). Our aim was to assess the prevalence of factor V Leiden mutation and other thrombophilic factors as risk factors in the development of PVT in the pediatric age group. From March 2001 to January 2002, 40 children with PVT were enrolled in the study, in addition to 20 age-matched and sex-matched controls. Protein C, protein S, antithrombin III, and activated protein C resistance (APCR) were assayed. Molecular study of factor II and factor V mutations was carried out. Of the patients, 25 had detectable hereditary thrombophilia (62.5%), 12 had factor V Leiden mutation (30%), 11 had protein C deficiency (27.5%), 6 had factor II mutation (15%), 1 had antithrombin III deficiency (2.5%), and none had protein S deficiency. Five children had concurrence of more than one defect. Factor V Leiden mutation is the most common hereditary thrombophilia associated with PVT and the relative risk of factor V Leiden mutation, as a cause of PVT, was six times more than in controls (odds ratio=6). Concurrence of more than one hereditary thrombophilic factor was seen in 12.5% of our patients. Circumstantial risk factors (neonatal sepsis, umbilical sepsis, umbilical catheterization) were not more significantly prevalent among patients with hereditary thrombophilia than among those with no detectable abnormalities in anticoagulation.