1/6. Large vessel arteritis associated with human herpesvirus 6 infections.A 9-month-old boy presented with chronic arteritis of the aorta and its major branches. The clinical manifestations at onset of his illness were compatible with those of Kawasaki syndrome. However, the febrile period lasted for 2 months despite various immunosuppressive therapies, and the levels of c-reactive protein remain high 18 months after onset. Elevated circulating immune complexes, decreased serum complement levels, hypergammaglobulinaemia and monoclonal gammopathy were observed. Active HHV-6 infection was shown by increased serum levels of antihuman herpesvirus-6 (HHV-6) IgG and IgM antibodies, and positive HHV-6 dna in sera, peripheral blood mononuclear cells (PBMNC) and lymph nodes. HHV-6 was actively replicating in PBMNC and lymph nodes, as shown by the detection of transcripts for the virus structural antigen. These results suggest that large vessel arteritis can be associated with HHV-6 infection.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
2/6. Human herpesvirus 6 genome and antigen in acute multiple sclerosis lesions.Evidence for a candidate multiple sclerosis (MS) virus, human herpesvirus 6 (HHV-6), was sought in biopsy specimens of acute lesions that presented clinically as cerebral tumors obtained from 5 patients. Histopathology, magnetic resonance imaging, and clinical course confirmed the diagnosis of MS in each case. A sensitive in situ polymerase chain reaction (ISPCR) method was used to detect HHV-6 genome, in conjunction with immunocytochemical staining (ICC) to detect viral and cellular antigens. ISPCR revealed numerous oligodendrocytes, lymphocytes, and microglia containing HHV-6 genome within all lesions, whereas ICC showed only the HHV-6 glycoprotein 116 antigen in some reactive astrocytes and microglia. High frequencies of neuroglial and inflammatory cells containing HHV-6 genome were present in acute-phase lesion tissue from patients who were free of the effects of chronic MS and had not been received immunomodulatory therapy for MS. The prevalence of HHV-6 genome-containing cells, including oligodendrocytes, in each lesion suggests that HHV-6 plays a role in the demyelinative pathogenesis of MS; the significance of the discrepant expression of viral antigens remains uncertain.- - - - - - - - - - ranking = 7keywords = antigen (Clic here for more details about this article) |
3/6. Drug-induced hypersensitivity syndrome associated with Epstein-Barr virus infection.association of drug-induced hypersensitivity syndrome with viral infection is debated. Human herpesvirus 6 (HHV-6) reactivation has been the most frequently reported infection associated with this syndrome. However, a case of cytomegalovirus (CMV) infection was recently described associated with anticonvulsant-induced hypersensitivity syndrome. We report a case of severe allopurinol-induced hypersensitivity syndrome with pancreatitis associated with Epstein-Barr virus (EBV) infection. Active EBV infection was demonstrated in two consecutive serum samples by the presence of anti-EBV early antigen (EA) IgM antibodies and an increase in anti-EBV EA IgG antibodies, whereas no anti-EBV nuclear antigen IgG antibodies were detected. EBV dna was detected by polymerase chain reaction (PCR) in peripheral blood mononuclear cells. Reactivation of HHV-6 was suggested only by the presence of anti-HHV-6 IgM antibodies, but HHV-6 dna was not detected by PCR in the serum. Other viral investigations showed previous infection (CMV, rubella, measles, parvovirus B19), immunization after vaccination (hepatitis b virus), or absence of previous infection (hepatitis c virus, human immunodeficiency virus). We suggest that EBV infection may participate in some cases, as do the other herpesviruses HHV-6 or CMV, in the development of drug-induced hypersensitivity syndrome.- - - - - - - - - - ranking = 2keywords = antigen (Clic here for more details about this article) |
4/6. Successful treatment of life-threatening human herpesvirus-6 encephalitis with donor lymphocyte infusion in a patient who had undergone human leukocyte antigen-haploidentical nonmyeloablative stem cell transplantation.BACKGROUND: Encephalitis as the result of human herpesvirus (HHV)-6 is usually fatal when it is resistant to antiviral drugs. methods: We describe a patient who developed HHV-6 encephalitis after human leukocyte antigen-haploidentical transplantation using a reduced intensity regimen. RESULTS: The patient developed severe disorientation, amnesia, and tremors on day 28. magnetic resonance imaging of the brain revealed limbic encephalitis, and the cerebrospinal fluid sample was positive for only HHV-6 in polymerase chain reaction analysis. Neither ganciclovir nor foscarnet was effective. The patient recovered from the critical condition of HHV-6 encephalitis after donor lymphocyte infusion (DLI). Almost all of his symptoms resolved, polymerase chain reaction tests for HHV-6 in the cerebrospinal fluid were negative, and magnetic resonance imaging findings were normal. CONCLUSIONS: This is the first report of DLI as a treatment for HHV-6 encephalitis and the first report of DLI from an human leukocyte antigen-haploidentical donor as a treatment for life-threatening viral infection.- - - - - - - - - - ranking = 6keywords = antigen (Clic here for more details about this article) |
5/6. Human herpesvirus-6-associated acute lymphadenitis in immunocompetent adults.In contrast to other causes of herpetic lymphadenitis, the histological features associated with human herpesvirus-6 (HHV-6) infection have remained elusive since its discovery in 1986. We describe the histologic and phenotypic changes associated with acute HHV-6 lymphadenitis in two immunocompetent adults who presented with fever, fatigue, generalized lymphadenopathy, and elevated liver enzymes. serologic tests for human immunodeficiency virus, acute Epstein-Barr virus, and cytomegalovirus infection were negative. Lymph node biopsies were consistent with viral lymphadenitis. Intranuclear and cytoplasmic inclusions were identified in CD4-positive T lymphocytes in expanded paracortical areas. Immunohistochemical staining with monoclonal antibody to the HHV-6 gp60/110 kDa envelope glycoprotein showed that the inclusions were positive for viral antigen. Electron microscopy demonstrated numerous viral particles in the cytoplasm and nucleus, characteristic of herpesviridae family. Clustering of viral particles was observed, which has previously been reported only in infected tissue culture cells. PCR followed by sequencing of dna extracted from the lymph nodes identified the virus as HHV-6, type B. This is the first report that documents distinctive histologic features of HHV-6 lymphadenitis and demonstrates that the cells harboring the virus in vivo are CD4-positive T lymphocytes.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
6/6. Post-mortem diagnosis of encephalitis in a 75-year-old man associated with human herpesvirus-6 variant A.An HHV-6 variant A infection is described in a 75 year-old man in association with meningoencephalitis identified at autopsy. The patient presented with fever and anorexia, then he developed altered consciousness, motor weakness, progressive lethargy, and coma, and died 21 days after hospital admission. Histopathological examination showed perivascular lymphocytic infiltrates in the central nervous system (CNS). serum and cerebral spinal fluid (CSF) samples drawn from the patient were tested for viruses by a nested polymerase chain reaction (nPCR). HHV-6 primers A and C [Aubin et al., 1991: J Clin Microb 29: 367-372] and HS6AE and HS6AF from [Dewhurst et al. (1993): J Clin Microb 31: 416-418] disclosed a 750 bp genomic product of HHV-6 in both types of biological samples. Restricted site analysis showed that the HHV-6 dna amplified belonged to the variant A of the virus. Short sequences of HHV-6 dna could also be detected in the dna extracted from formalin-fixed, paraffin-embedded sections of CNS tissues by use of one (GM5 and GM6) of three pairs of HHV-6 primers that were selected. Immunohistochemical examination of brain sections, employing a specific monoclonal antibody directed against the HHV-6 gp 102 protein, detected the viral antigen in neurons and glial cells.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |