1/6. Bone marrow failure associated with human herpesvirus 8 infection after transplantation.BACKGROUND: Human herpesvirus 8 (HHV-8) infection has been linked to the development of Kaposi's sarcoma and to rare lymphoproliferative disorders. methods: We used molecular methods, serologic methods, in situ hybridization, and immunohistochemical analyses to study HHV-8 infection in association with nonmalignant illnesses in three patients after transplantation. RESULTS: Primary HHV-8 infections developed in two patients four months after each received a kidney from the same HHV-8-seropositive cadaveric donor. Seroconversion and viremia occurred coincidentally with disseminated Kaposi's sarcoma in one patient and with an acute syndrome of fever, splenomegaly, cytopenia, and marrow failure with plasmacytosis in the other patient. HHV-8 latent nuclear antigen was present in immature progenitor cells from the aplastic marrow of the latter patient. Identification of the highly variable K1 gene sequence of the HHV-8 genome in both the donor's peripheral-blood cells and the recipients' serum confirmed that transmission had occurred. HHV-8 viremia also occurred after autologous peripheral-blood stem-cell transplantation in an HHV-8-seropositive patient with non-Hodgkin's lymphoma. Reactivation of the infection was associated with the development of fever and marrow aplasia with plasmacytosis; there was no evidence of other infections. HHV-8 transcripts and latent nuclear antigen were expressed in the aplastic marrow but not in two normal marrow samples obtained before transplantation. CONCLUSIONS: Primary HHV-8 infection and reactivation of infection may be associated with nonneoplastic complications in immunosuppressed patients.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
2/6. Virus-like particles in a case of acute hepatitis with human GB virus-C viraemia.BACKGROUND/AIMS: It is still controversial whether the human GB virus-C can cause liver injury, as in situ demonstration of the virus is still inconclusive. methods: Here we describe the case report of a patient with two episodes of severe acute hepatitis, who had a meticulous clinical, immunological and microbiological work-up, including human GB virus-C rna detection by in situ hybridization and electron microscopy. RESULTS: Human GB virus-C viraemia was found as the only potential cause of hepatitis in this patient. Furthermore, virus-like particles could be demonstrated in the cytoplasm of single hepatocytes by electron microscopy and human GB virus-C rna was detected in the liver by in situ hybridization. CONCLUSION: The presence of human GB virus-C rna in serum together with the demonstration of human GB virus-C rna in the liver, favour acute human GB virus-C infection as the cause of liver injury in this patient. Thus virus-like particles and hepatic human GB virus-C rna should be specifically looked for by electron microscopy and in situ hybridization, especially during the diagnostic work-up of patients with unexplained hepatitis.- - - - - - - - - - ranking = 3keywords = hybridization (Clic here for more details about this article) |
3/6. Epstein-Barr virus (EBV)-associated post-transplantation lymphoproliferative disorder simultaneously affecting both B and T cells after allogeneic bone marrow transplantation.Post-transplantation lymphoproliferative disorder (PTLD) is usually an aberrant proliferation of EBV-infected B cells. We report the case of a 31-year-old man with severe aplastic anemia who suffered PTLD 42 days post-BMT from an unrelated donor. At the onset of PTLD, peripheral blood lymphocytes were comprised of 40% CD20( ) cells, 3% CD4( ) cells, and 56% CD8( ) cells. A highly sensitive in situ hybridization (ISH) method was used to detect EBV-encoded small non-polyadenylated rna 1 (EBER-1) in 33.9% of sorted CD20( ) cells, 4.4% of CD4( ) cells, and 1.4% of CD8( ) cells. Each T-cell fraction contained less than 0.034% of contaminated EBV-infected B cells. Clonal proliferation of both B and T cells was demonstrated by Southern blotting. The patient did not respond to donor leukocyte infusion and died due to deterioration of PTLD. At autopsy, examination of multiple organs revealed B-cell (rather than T-cell) infiltration. This case clearly indicates that EBV can simultaneously infect B and T cells and can induce clonal proliferation of both lymphocyte subsets in severely immunocompromised patients.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
4/6. Cytomegalovirus viremia detected by molecular hybridization and electron microscopy.Fatal cytomegalovirus interstitial pneumonitis developed in a patient with chronic leukemia. The diagnosis was suspected on the basis of cytologic examination of bronchial washings. The virus was subsequently recovered from saliva, urine, and blood leukocytes after 8, 9, and 18 days in culture respectively. Premortem cytomegalovirus dna was found by molecular hybridization methods using a complete viral genome probe in blood leukocytes after 4 hours' reaction time. Electron microscopic examination showed herpes-like virions consistent with cytomegalovirus in 3% of the patient's granulocytes. Thus, dna:dna hybridization and ultrastructural methods can be used for rapid diagnosis of disseminated cytomegalovirus infection.- - - - - - - - - - ranking = 6keywords = hybridization (Clic here for more details about this article) |
5/6. Viral sensitivity testing in patients with cytomegalovirus retinitis clinically resistant to foscarnet or ganciclovir.PURPOSE: Resistance to antiviral therapy is a potential cause of progression of cytomegalovirus retinitis in patients with the acquired immunodeficiency syndrome. We investigated the results of viral sensitivity testing in a series of patients with clinically resistant retinitis who had positive results of blood or urine cytomegalovirus cultures. methods: All patients with newly diagnosed cytomegalovirus retinitis between January 1990 and December 1991 were prospectively studied. Blood and urine cultures for cytomegalovirus were obtained in a nonrandomized subgroup of this group. The results of in vitro sensitivity to foscarnet and ganciclovir, determined by a dna hybridization assay, were then analyzed in seven patients with clinically resistant cytomegalovirus retinitis and whose blood or urine culture results, or both, were positive for cytomegalovirus while on a treatment regimen. RESULTS: foscarnet-resistant cytomegalovirus (ID50 > 300 microM) was isolated from two patients, one of whom was being treated with foscarnet. ganciclovir-resistant cytomegalovirus (ID 50 > 6.0 microM) was isolated from four patients, three of whom were being treated with ganciclovir. foscarnet- and ganciclovir-resistant cytomegalovirus occurred with previous ganciclovir therapy in one patient. Clinical improvement occurred in three patients whose change in therapy was based on viral sensitivity testing. In general, prolonged therapy with one drug was associated with a progressive increase in the ID 50 for that drug. CONCLUSIONS: Viral resistance to foscarnet or ganciclovir may explain refractory cytomegalovirus retinitis in some patients.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
6/6. Five cases of cytomegalovirus infection detected by in situ hybridization and antigenemia assay.We report five cases of cytomegalovirus infection in immunocompromised patients which were detected by either cytomegalovirus antigenemia assay or in situ hybridization. Four cases had leukemia and the other had chronic renal failure. All the three BMT recipients suffered from GvHD. Interestingly, there was an unique case of CMV disease without a history of BMT, which reminded us that CMV could attack immunocompromised patients who had not undergone transplantation, too. Four out of five cases died. We think that cytomegalovirus infection or disease should not be regarded as a minor problem in post-transplantation infection in korea.- - - - - - - - - - ranking = 5keywords = hybridization (Clic here for more details about this article) |