1/38. Hypoperfusion of right hemisphere on brain SPECT in a patient with exanthem subitum and left hemiparesis. Left hemiparesis exhibited during the post-eruptive stage of exanthem subitum (ES) in an 11-month-old girl. Tc-99m HMPAO brain SPECT showed diffuse hypoperfusion in right hemisphere. Hemiparesis has occasionally been reported as central nervous system (CNS) complications of ES, and Tc-99m HMPAO brain SPECT was useful for evaluating of CNS involvement. ( info) |
2/38. Isolation and identification of human herpesvirus 7 from an infant with exanthem subitum. Exanthem subitum (ES) is a common childhood exanthematous disease. In a recent study of ES due to human herpesvirus 6 (HHV 6), we isolated human herpesvirus 7 (HHV 7) from the peripheral blood mononuclear cells (PBMC) of a seven month-old infant with typical symptoms of ES. The identity of the virus was confirmed by indirect immunofluorescence using HHV 7 specific monoclonal antibody and by amplification of the HHV 7 specific genomic sequences using the polymerase chain reaction (PCR). Paired serum samples from the infant showed serological conversion to the isolated virus. The clinical manifestations of ES in this infant appeared to be milder than the classical ES due to HHV 6. ( info) |
3/38. A practitioner's guide to human herpesvirus-6 (HHV-6) and human herpesvirus-7 (HHV-7). Human herpesvirus-6 (HHV-6) and HHV-7 are newly recognized ubiquitous human viruses first discovered in patients with AIDS or lymphoproliferative disorders. Much more information is available about the clinical characteristics of infection with HHV-6 than HHV-7. Primary infection with HHV-6 occurs in early childhood and is most commonly manifested as an undifferentiated highly febrile illness, with seizures noted to be the most common complication. A subset of children develop the classic manifestations of roseola infantum or exanthem subitum. Other neurologic diseases in adults such as encephalitis and multiple sclerosis also have been linked to HHV-6; however, the role of HHV-6 in these clinical entities has not been fully elucidated. Although HHV-6 and hiv are both tropic for CD4 lymphocytes and interact in vitro, there is no evidence at present that HHV-6 plays a role in hiv disease. HHV-7 is similar to HHV-6 in genetic organization and structure. Little is known of the clinical characteristics of infection with HHV-7 or its ability to cause disease in children or reactivation in adults. ( info) |
4/38. 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. ( info) |
| Experience with confirmed high fever, 40 C (104 F) or more, in a private practice during 14 years is presented. The records of 1,500 patients covering 8,000 patient years disclosed only 108 confirmed episodes of high fever. Eleven diagnostic categories included 149 diagnoses. Fourteen of 43 roentgenographic examinations yielded positive findings, including two cases of pneumonia not detected on physical examination. Two of six stool cultures yielded specific enteric pathogens. Convulsions occurred in 12 of the 108 episodes of high fever, and recurred only once in one child. There were no deaths in this series of children with high fevers. Only one diagnosis, pneumonia, was significantly more frequent in confirmed high fever than in unconfirmed high fever. Lastly, the ability of a group of mothers to read thermometers set at three different temperatures proved to be surprisingly good. ( info) |
| A 5 month old girl had typical clinical features of acute myocarditis just after the febrile period of exanthem subitum and died immediately. She had been healthy, with normal development, and there was no family history of particular note. Myocardial postmortem findings were compatible with acute myocarditis. Although the isolation of human herpesvirus 6 (HHV-6) was not attempted, positive IgM antibody to HHV-6 was detected in the patient's serum. Moreover, HHV-6 variant B dna was detected in several tissues, including myocardium, by the polymerase chain reaction (PCR). In contrast, antibody responses to human herpesvirus 7, another causal agent of exanthem subitum, were not found, and enteroviral rna was not detected in myocardial tissues by reverse transcription PCR. Apoptotic changes were seen in infiltrating cells within the myocardial tissues by means of the TUNEL method. HHV-6 antigen was not detected in several tissues (including myocardium) by immunohistochemical analysis. In conclusion, HHV-6 may have been the causative agent of fatal acute myocarditis in this infant. ( info) |
7/38. Fatal human herpesvirus 6-associated multifocal meningoencephalitis in an adult female patient. Human herpesvirus 6 (HHV 6) is a known cause of central nervous system infection in immunocompromised patients. Less is known about the clinical course of HHV 6 encephalitis in immunocompetent patients. We report a case of meningoencephalitis in a 42-y-old immunocompetent patient associated with HHV 6 infection. ( info) |
8/38. Human herpesvirus-6 infection in neonates: Not protected by only humoral immunity. BACKGROUND: Infants are usually protected from various viral infections, including human herpesvirus-6 (HHV-6) and human herpesvirus-7 (HHV-7) infections, during the early infantile period by antibodies transferred from their mothers. However, rare cases of exanthem subitum (ES) in neonates have been described in published reports. methods: From the infantile patients of febrile illness, HHV-6 and HHV-7 dna were examined by the polymerase chain reaction method. antibodies to HHV-6 and HHV-7 were detected by indirect immuno-fluorescence assay and neutralization test. Viral isolation was attempted from the patient's peripheral blood mononuclear cells (PBMC) during the acute phase of febrile illness. RESULTS: Human herpesvirus-6 was verified virologically in two neonates who were clinically diagnosed as ES within the first month of life. Although high copies of HHV-6 dna were detected in their PBMC during the acute phase, the isolation of HHV-6 from their PBMC was not successful. Neutralizing antibodies to HHV-6 were detected in sera of the acute phase, and those antibodies were considered to be transferred from their mothers. Antibody titers showed fourfold elevation in sera of the convalescent phase. The HHV-6 infection occurred despite the presence of pre-existing maternal antibody. Human herpesvirus-7 and HHV-7 dna were not detected from their clinical samples. CONCLUSIONS: This observation suggests that HHV-6 infection could not be protected by only humoral immunity. ( info) |
9/38. Human herpesvirus 6 encephalitis associated with hypersensitivity syndrome. Hypersensitivity syndrome, a serious systematic reaction to a limited number of drugs, is associated with the reactivation of human herpesvirus 6. A 56-year-old man developed acute limbic encephalitis followed by multiple organ failure during the course of toxic dermatitis induced by aromatic anticonvulsants. The clinical features of skin eruptions, high fever, eosinophilia, and atypical lymphocytosis were compatible with drug hypersensitivity syndrome. The patient showed seroconversion for human herpesvirus 6, and polymerase chain reaction detected human herpesvirus 6 dna in the cerebrospinal fluid. To our knowledge, this is the first report of human herpesvirus 6 encephalitis associated with hypersensitivity syndrome. ( info) |
| A female infant developed guillain-barre syndrome 20 days after having exanthem subitum confirmed serologically as human herpesvirus 6 infection. dna of human herpesvirus 6 was detected in peripheral blood mononuclear cells collected on admission. ( info) |