CHILDREN INFECTED WITH HCV AFTER CARDIAC SURGERY DURING INFANCY SHOW A HIGH SPONTANEOUS CLEARANCE RATE OF THE VIRUS. A STUDY ON 458 PATIENTS.

Abstract

170 Hepatitis C is the main cause of post transfusion hepatitis. Clinical course and risk of cirrhosis seem to be different in children infected early in their life compared to adults. However, only a few data exist about this observed difference. We examined 458 patients who had undergone cardiac surgery during their first year of life at the German Heart Center before 1991. All patients were screened for anti HCV-antibodies to investigate the prevalence in this group of patients. Anti-HCV positive patients were further examined for elevation of transaminases, γGT, IgG and HCV-RNA in serum. All RNA-positive patients were genotyped (RFLP), a subset of 10 HCV-RNA positive patients was liver biopsied. Results: 67 patients out of 458 patients were HCV seropositive (prevalence of 13.6%) as confirmed by western blot analysis. 27 of 67 anti-HCV positive patients were positive for HCV-RNA with a duration of infection between 8 and 27 years (genotypes: 1a 15pt., 1b 11pt., 3a 1pt). 22 anti-HCV positive patients were RNA negative as confirmed by three consecutive HCV-RNA-analyses within one year. All of them have been infected by blood transfusions during the first year of life and lost the virus within 8 to 28 years. There were no significant differences between RNA-positive and RNA negative patients regarding transaminases,γGT, or bilirubin. However, there was a tendency towards higher IgG-levels in the RNA-positive group. Liver biopsies in a subset of 10 RNA positive patients showed only very mild portal inflammation without parenchymal lesions in 9 patients, cirrhosis was found in only one patient due to coinfection with HCV and HBV. Summary: Our results show a prevalence of 13.6% of HCV among pediatric patients who underwent cardiac surgery before 1991, 13 times higher compared to the normal German population. Surprisingly most of the patients have normal transaminases even 27 years after beeing infected. 27 of 67 anti-HCV antibody positive patients were still RNA positive with a predominance of the genotypes 1a and 1b. However up to now 33% of anti HCV positive patients lost their HCV-virus within 8-27 years of infection. Liver biopsies in subset of 10 RNA-positive patients showed only minor portal inflammation in 9 of 10. Conclusion: HCV-infection in early childhood seems to coincide with a higher spontaneous clearance of the virus and a very slow progression of liver damage compared to patients who aquired the disease as adults. This observation might be due to a different immunological response against the virus in infants compared to adults.