1/6. Efficacy of lamivudine for the treatment of hepatitis b virus infection after liver transplantation in children.BACKGROUND: There is at present very little information about hepatitis b virus (HBV) infection in children after liver transplantation. This is the first study to assess the safety and efficacy of lamivudine in this patient population. methods: We describe three children aged 5-14 years who underwent liver transplantation for fulminant hepatitis a, hyperoxaluria, and cystic fibrosis. Despite adequate immunoprophylaxis, two of the children who were serum hepatitis B surface antigen-positive before transplantation (HBV dna-negative by hybridization) had a reactivation of the disease, and one had a de novo HBV infection, at 12-18 months after transplantation. lamivudine 3 mg/kg was administered on a compassionate-use basis for 14-36 months. RESULTS: After 1 month of therapy, HBV dna disappeared from the serum in all patients by hybridization and in two patients by polymerase chain reaction. In all three children, alanine transaminase levels normalized. One child developed lamivudine resistance after 22 months with no evidence of hepatic decompensation. Repeated liver histological studies revealed progression of hepatic fibrosis in one child. All children remained serum hepatitis B surface antigen- and hepatitis B e antigen-positive. No adverse effects of the drug were noted. CONCLUSION: lamivudine is beneficial and well tolerated in children with HBV infection after liver transplantation.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
2/6. Are there histopathologic characteristics particular to fulminant hepatic failure caused by human herpesvirus-6 infection? A case report and discussion.An 8-month-old boy was admitted to a neighboring hospital for severe liver dysfunction and drowsiness 4 days after a diagnosis of exanthem subitum. A diagnosis of fulminant hepatic failure was made, and liver biopsy was performed during the acute stage. The presence of human herpesvirus-6 variant B (HHV-6B) dna was shown in liver tissue by polymerase chain reaction (PCR) and in the endothelium of the portal vein by in situ hybridization (ISH). Histologic examination showed microvesicular steatosis resembling that of Reye's syndrome, even though aspirin had not been prescribed. We considered HHV-6 to be the causative agent in this case and report what is perhaps the first precise histologic description of fulminant hepatic failure caused by HHV-6.- - - - - - - - - - ranking = 0.5keywords = hybridization (Clic here for more details about this article) |
3/6. Congenital anerythremic erythroleukemia presenting as hepatic failure.We report an atypical case of congenital erythroleukemia in a child born with hepatosplenomegaly and abnormal liver tests. The initial peripheral blood cell count showed anemia and hyperleukocytosis with erythroblastosis that disappeared 1 week later. During the next 5 weeks, no blasts were found in the blood, and less than 5% were found on 2 successive bone marrow aspirates. The infant died of hepatic failure. The suspected diagnosis on a premortem liver biopsy was confirmed by an autopsy that showed a blastic infiltration in many organs. These cells expressed only erythroid markers glycophorin A and C. Rearrangement of the myeloid lymphoid leukemia gene was not found by fluorescence in situ hybridization. The main differential diagnoses include metabolic diseases, Langerhans histiocytosis, Pepper syndrome, transient myeloproliferative disorder, and leukemoid reactions. Although some of these can be excluded by the pathologist, others require a multidisciplinary confrontation: clinical, biologic, genetic, and pathologic examinations.- - - - - - - - - - ranking = 0.5keywords = hybridization (Clic here for more details about this article) |
4/6. Life-threatening infectious mononucleosis: is it correlated with virus-induced T cell proliferation?infectious mononucleosis is a well-established clinical entity characterized by the proliferation of B lymphocytes that are infected with Epstein-Barr virus (EBV). These lymphocytes give rise to an increase in specifically reacting cytotoxic T cells, which leads to self-limitation of the lympho-proliferative process. We describe the case of a 1-year-old boy who developed life-threatening EBV infection in association with liver failure, depletion of bone marrow, and severe encephalitis. The fact that clinical cure was achieved when acyclovir (50 mg/[kg.d]) and prednisolone (1 mg/[kg.d]) were administered indicates a correlation between antiviral therapy and clinical improvement. Hypogammaglobulinemia--which had not been present at the onset of disease--persisted after clinical recovery. During the acute phase of the illness, the patient's blood lymphocytes were predominantly T cells, most of which contained the EBV genome, as shown by in situ hybridization; some of these cells stained positive for EBV-specific latent membrane protein. Examination of peripheral blood mononuclear cells in vitro revealed an exceedingly high histocompatibility antigen-unrestricted cytotoxicity against the K562 cell line, which is normally not an immunogenic target of cytotoxic cells in patients infected with EBV. This anomalous natural killer cell-like T cell function suggests that EBV infection of T cells might cause auto-aggressive activity, which was probably responsible for the severity of the infection in our patient.- - - - - - - - - - ranking = 0.5keywords = hybridization (Clic here for more details about this article) |
5/6. Rapid hepatic failure associated with a contracted liver mimicking cirrhosis in a case of nasopharyngeal carcinoma with liver metastasis.A 46-year-old women had an undifferentiated nonkeratinizing nasopharyngeal carcinoma, locally controlled by radiotherapy. Initially, she had normal liver function tests and normal hepatic ultrasonography. Seven months later, she experienced a rapidly progressive hepatic failure manifested by the development of ascites, elevation of serum bilirubin level, and prolongation of prothrombin time. Imaging studies showed a contracted liver and serum biochemical tests were compatible with chronic liver disease, except for an increase of alkaline phosphatase and gamma-glutamyl transpeptidase levels. An endoscopic retrograde cholangiogram ws compatible with changes of sclerosing cholangitis. The patient died of hepatic decompensation within two months. A liver necropsy disclosed diffuse infiltration of carcinoma cells into the hepatic sinusoids and obliterative angio-invasion of the tumor cells with massive fibrotic stroma replacing almost all hepatocytes. in situ hybridization demonstrated expression of Epstein-Barr virus transcripts EBER1 in the tumor cells and proved a metastatic nasopharyngeal carcinoma. The contracted liver is likely to be explained by the tumor-associated desmoplastic change and the obliterative angio-invasion of the tumor. It is important to be aware that, although rare, such an unusual pattern of liver metastasis may mimick cirrhosis clinically and cause rapid hepatic failure in patients with nasopharyngeal carcinoma.- - - - - - - - - - ranking = 0.5keywords = hybridization (Clic here for more details about this article) |
6/6. Donor origin of posttransplant lymphoproliferative disorder localized to a liver allograft: demonstration by fluorescence in situ hybridization.SETTING: Posttransplant lymphoproliferative disorders in solid organ transplantation are mostly of recipient origin. We report an unusual case of posttransplant lymphoproliferative disorder following liver transplantation with localized limited involvement of the solid organ allograft. DESIGN: tissues were obtained at the time of surgery and evaluated by immunohistochemistry, in situ hybridization, and fluorescence in situ hybridization with chromosome X and Y centromeric probes. PATIENT: A 53-year-old Hispanic man with hepatic failure due to hepatitis c virus who underwent orthotopic liver transplant from a female donor and developed posttransplant lymphoma in the transplanted liver. INTERVENTION: Withdrawal of immunosuppression, resection of liver allograft, and second transplant. RESULTS: This posttransplant lymphoproliferative disorder was clearly shown to be derived from Epstein-Barr virus-infected donor lymphoid cells. This was demonstrated by fluorescence in situ hybridization for X and Y chromosomes in paraffin sections in a sex-mismatched transplant. Despite aggressive histology (monoclonal B-cell immunoblastic lymphoma) and lack of response to withdrawal of immunosuppression, the posttransplant lymphoproliferative disorder was successfully managed by repeat liver transplantation without recurrence. CONCLUSION: fluorescence in situ hybridization was used to prove donor derivation in a posttransplant lymphoma of the liver. Allograft-localized donor posttransplant lymphoproliferative disorder may represent a unique category with more favorable prognosis requiring different clinical management from other cases.- - - - - - - - - - ranking = 4keywords = hybridization (Clic here for more details about this article) |