Herpesviruses oral shedding and viremia in renal transplant recipients: A longitudinal study.

BACKGROUND: The objective was to assess the oral shedding and viremia of human herpesviruses in renal transplant recipients. METHODS: This is a cohort study in which the participants were examined in three different periods: the first within 24 hours before renal transplantation and the second and third ones 15-20 and 45-60 days after the transplantation. Mouthwash and blood samples were collected in each period and then submitted to screening for the presence of eight types of human herpesviruses by using multiplex PCR. RESULTS: HSV-1 and EBV were more frequent in the saliva after renal transplantation, 15- to 20-day period after the transplant. EBV was found in the saliva of 26 (35.6%) patients before renal transplantation and in 56.2% and 46.6% of them, in the 15- to 20-day and 45- to 60-day periods after the transplant, respectively. High detection rates (75.3%-78.1%) were found for HHV-7 despite the lack of significant variations between the study periods. There was no concordance between herpesviruses oral shedding and viremia. CONCLUSION: We concluded that the pattern of excretion of HSV-1 and EBV in saliva is changed immediately after renal transplantation, increasing in the 15- to 20-day period after the transplant surgery. No concordance between herpesviruses oral shedding and viremia was observed.

Pitiriasis rosada en el embarazo: reporte de caso / Pityriasis rosea in pregnancy: case report

RESUMEN A pesar de que la Pitiriasis Rosada se considera una condición cutánea benigna, en el marco del embarazo, hay estudios que relacionan la aparición de esta patología con complicaciones asociadas en el feto. Metodología: Se realiza un reporte de caso, prospectivo, a una mujer de 36 años chilena que presentó esta patología durante la semana 12 de gestación. El objetivo fue describir, la evolución y control y contrastar su evolución con la evidencia científica actual sobre esta temática. Resultados: Paciente presenta placas eritematodescamativas concordantes con diagnóstico de pitiriasis rosada (superficie afectada menos al 50% de su cuerpo), sin presentar enantema, ni síntomas sistémicos. Tuvo un recién nacido sano a las 38 semanas de gestación, sin presentar ningún efecto adverso de los que relaciona la literatura analizada. Conclusiones: Distintos estudios han estudiado los posibles efectos adversos en el feto en madres que han presentado Pitiriasis Rosada en el embarazo, sin embargo, en este reporte de caso no se presentaron complicaciones asociadas. Faltan estudios realizados en mayor cantidad de pacientes.

ABSTRACT Although Pityriasis Rosea is considered a benign cutaneous condition, in the context of pregnancy, there are studies that relate the appearance of this pathology with associated complications in the fetus. Methodology: A prospective case report was made to a 36-year-old Chilean woman who presented this pathology during the twelve weeks of pregnancy. The objective was to describe, the evolution and control and to contrast its evolution with the current scientific evidence on this subject. Results: Patient presents concordant erythematous-desquamative plaques with diagnosis of Pityriasis Rosea (surface affected less than 50% of his body), without presenting enanthem, nor systemic symptoms. Had a healthy newborn at 38 weeks of gestation, without presenting any adverse effect related to the analyzed literature. Conclusions: Different studies have studied the possible adverse effects on the fetus in mothers who have presented pityriasis rosea in pregnancy, however in this case report there were no associated complications. Missing studies in a greater number of patients.

Polirradiculoneuritis aguda asociada a infección por Virus Herpes Humano 7 en un paciente adulto inmunocompetente / Acute polyradiculoneuropathy associated with human Herpes Virus 7 in an immunocompetent patient: case report

Human herpes virus 7 (HHV-7) is a cause of encephalitis, meningitis and myeloradiculoneuropathy in adults who are immunocompetent or with immunosuppression. The involvement of the peripheral nervous system is always associated with myelitis. We report a case of acute polyradiculoneuropathy due to HHV-7, without involvement of central nervous system, in an immunocompetent patient. A 35-years-old man complained of lumbar pain radiating to both buttocks. On examination muscle strength and tendon reflexes were normal. He had asymmetric pinprick and light touch saddle hypoesthesia and also in the perineal region, dorsum and lateral aspect of the left foot. Magnetic resonance imaging showed mild thickening and contrast enhancement of cauda equina nerve roots. Polymerase chain reaction performed on cerebrospinal fluid was positive for HVV-7. Other inflammatory, infectious and neoplastic etiologies were ruled out. Lumbar pain and hypoesthesia improved progressively and neurological examination was normal after one month. He did not receive antiviral therapy.

[Acute polyradiculoneuropathy associated with human Herpes Virus 7 in an immunocompetent patient. Case report]. / Polirradiculoneuritis aguda asociada a infección por Virus Herpes Humano 7 en un paciente adulto inmunocompetente.

Human herpes virus 7 (HHV-7) is a cause of encephalitis, meningitis and myeloradiculoneuropathy in adults who are immunocompetent or with immunosuppression. The involvement of the peripheral nervous system is always associated with myelitis. We report a case of acute polyradiculoneuropathy due to HHV-7, without involvement of central nervous system, in an immunocompetent patient. A 35-years-old man complained of lumbar pain radiating to both buttocks. On examination muscle strength and tendon reflexes were normal. He had asymmetric pinprick and light touch saddle hypoesthesia and also in the perineal region, dorsum and lateral aspect of the left foot. Magnetic resonance imaging showed mild thickening and contrast enhancement of cauda equina nerve roots. Polymerase chain reaction performed on cerebrospinal fluid was positive for HVV-7. Other inflammatory, infectious and neoplastic etiologies were ruled out. Lumbar pain and hypoesthesia improved progressively and neurological examination was normal after one month. He did not receive antiviral therapy.

Detection of Merkel cell polyomavirus in oral samples of renal transplant recipients without Merkel cell carcinoma.

Merkel cell carcinoma (MCC) is a rare but aggressive neuroendocrine cancer, with approximately 80% of cases associated with Merkel cell polyomavirus (MCPyV). The lack of information concerning its occurrence in non-MCC immunosuppressed populations led to the investigation of MCPyV DNA in saliva and oral biopsies from 60 kidney allograft recipients and 75 non-transplanted individuals (control group). In contrast to herpesviruses, which was also investigated (CMV, HHV-6A, and B, HHV-7) MCPyV was detected predominantly in patients with oral lesions (gingivitis and/or periodontitis) of both transplanted and non-transplanted groups (P=0.016) and in the saliva of the transplanted group (P=0.009). MCPyV co-detection with CMV (P=0.048), and HHV-6 (P=0.020) in the saliva of transplanted patients requires further investigation on a possible role of co-infection.

Correlation of cytomegalovirus and human herpesvirus 7 with CD3+ and CD3+ CD4+ cells in chronic periodontitis patients.

BACKGROUND AND OBJECTIVE: Human chronic periodontitis is an inflammatory process characterized by dense accumulation of immune cells in the periodontal tissue. The periodontitis can lead to loss of teeth in the patient and the pathogenesis of this disease is not completely known. This study tested the hypothesis that chronic periodontitis-affected sites can harbor betaherpesviruses and that viruses are linked to a profile of the inflammatory infiltrate. MATERIAL AND METHODS: Biopsies of periodontal tissue were taken from periodontitis-affected patients and from healthy subjects. Immunohistochemistry was performed to count CD19(+) B cells, CD3(+) total T cells, T-CD4(+) and T-CD8(+) cell subsets, and PCR was performed to detect cytomegalovirus and human herpesvirus 6 and 7 in the samples. One slide of each sample was stained with Giemsa for histopathological examination and to evaluate the quality of the cellular infiltrate. RESULTS: As expected, tissues collected from healthy subjects presented no significant level of inflammatory infiltration and were therefore excluded from immunostaining procedures. Results showed that CD19(+) B cells were in higher number than CD3(+) T cells in the periodontitis-affected tissue, but this was not statistically significant. The T-CD4(+) lymphocyte subset was significantly higher than the T-CD8(+) lymphocyte subset (p = 0.004) in the samples. Cytomegalovirus and human herpesvirus 7 were found at periodontitis-affected sites, but not in tissue collected from healthy subjects (p = 0.04 and p = 0.04, respectively). Human herpesvirus 6 was rarely detected. We found a correlation between cytomegalovirus and lower CD19(+) /CD3(+) ratios (ratio < 0.9, p = 0.003) and between human herpesvirus 7 and lower CD19(+) /CD3(+) ratios (ratio < 0.9, p = 0.003) and higher CD4(+) /CD8(+) ratios (ratio > 1.1, p = 0.002). CONCLUSION: This study shows that cytomegalovirus and human herpesvirus 7 can be present at periodontitis-affected sites but are uncommon at healthy periodontal sites. Moreover, our data suggest that cytomegalovirus can be related to an inflammatory infiltrate with predominance of CD3(+) T cells, whereas human herpesvirus 7 can be associated with an infiltrate with predominance of T-CD4(+) cells. However, further studies are necessary to support this hypothesis. Herpesviruses could play a role in human chronic periodontitis by modulation of the T cell response.

Detection of human herpesvirus 7 infection in young children presenting with exanthema subitum.

In this study, we assessed the prevalence of human herpesvirus-7 (HHV-7) in 141 serum samples from children less than four years of age with exanthematic disease. All samples were negative for measles, rubella, dengue fever and parvovirus B19 infection. Testing for the presence of human herpesvirus-6 (HHV-6)-specific high avidity IgG antibodies by indirect immunofluorescence assay (IFA) revealed two main groups: one composed of 57 patients with recent primary HHV-6 infection and another group of 68 patients showing signs of past HHV-6 infection. Another 16 samples had indeterminate primary HHV-6 infection, by both IgG IFA and IgM IFA. Serum samples were subjected to a nested polymerase chain reaction to detect the presence of HHV-7 DNA. Among patients with a recent primary HHV-6 infection, HHV-7 DNA was present in 1.7% of individuals; however, 5.8% of individuals tested positive for HHV-7 DNA in the group with past primary HHV-6 infection. Among the 16 samples with indeterminate diagnosis, 25% (4/16) had HHV-7 DNA (p < 0.002). We hypothesise that HHV-7 might be the agent that causes exanthema. However, a relationship between clinical manifestations and the detection of virus DNA does not always exist. Therefore, a careful interpretation is necessary to diagnose a primary infection or a virus-associated disease. In conclusion, we detected HHV-7 DNA in young children from the state of Rio de Janeiro, Brazil.

[Meningomyelitis associated with infection by human herpes virus 7: report of two cases]. / Meningomielitis asociadas a infección por herpes virus humano 7: Comunicación de dos casos.

Human herpesvirus 7 (HHV-7) may cause encephalomyelitis in immune competent adults. We report two patients infected by the virus. A 34-year-old male presenting with paraparesis and a sensitive deficiency located in D6 dermatome. Cerebrospinal fluid had 35 white blood cells per mm³ and 75 mg protein per dl. A PCR-microarray examination was positive for HHV-7. The patient was treated with prednisolone and ganciclovir with full recovery. A 27-year-old male presenting with headache, fever and diarrhea. Cerebrospinal fluid analysis showed 160 cells per mm³ and 75 mg protein per dl. Viral RNA detection was positive for HHV-7. The patient was managed with analgesia and rest and was discharged with the diagnosis of viral meningitis. Our communication supports the notion that HHV-7 may be considered as pathogen factor in humans, even in immune competent ones.

Detection of human herpesvirus 6 and 7 DNA in saliva from healthy adults from Rio de Janeiro, Brazil.

In this study, we aimed to evaluate virus shedding in the saliva of healthy adults from the metropolitan region of the city of Rio de Janeiro, Brazil, in order to verify the prevalence of both human herpesviruses 6 and 7 (HHV-6, HHV-7). The studied group comprised 182 healthy individuals at Pedro Ernesto University Hospital, who were being seen for annual odontologic revisions. Saliva specimens were subjected to a multiplex polymerase chain reaction (PCR) to detect the presence of HHV-6A, HHV-6B and HHV-7. The total Roseolovirus DNA prevalence was 22.4%. The PCR detected a HHV-6 prevalence of 9.8%, with HHV-6A detected in 7.1% of the samples and HHV-6B in 2.7%. HHV-7 DNA was revealed in 12.6% of the studied cases. Multiple infections caused by HHV-6A and 7 were found in 2.1% of the samples. No statistical differences were observed regarding age, but for HHV-7 infection, an upward trend was observed in female patients. Compared to studies from other countries, low prevalence rates of herpesvirus DNA were detected in saliva from the healthy individuals in our sample. PCR methodology thus proved to be a useful tool for Roseolovirus detection and it is important to consider possible geographic and populations differences that could explain the comparatively low prevalence rates described here.

IgG subclasses and DNA detection of HHV-6 and HHV-7 in healthy individuals.

Human herpesvirus 6 (HHV-6) and 7 (HHV-7) are common opportunistic agents in immunocompromised hosts, although infection with HHV-6 and HHV-7 can also be observed in immunocompetent hosts. Despite similar biology and epidemiology, this study evaluated differences in the IgG subclass distribution associated with HHV-6 and HHV-7 in seropositive, healthy persons. The identified subclasses were also compared with the detection of HHV-6 and HHV-7 DNA. For these assays, sera, plasma, and saliva samples were obtained from 40 healthy blood donors in Argentina who were seropositive for both HHV-6 and HHV-7. HHV-6 and HHV-7 DNA were detected in saliva and plasma samples using nested PCR, and specific IgG subclasses were determined using immunofluorescent assays of sera samples. HHV-7 DNA was detected in 90% of all plasma samples and in 100% of saliva samples. In contrast, HHV-6 DNA was not detected in any of the plasma samples, and it was detected in only 6 of 40 saliva samples. Determination of IgG subclass distributions showed that HHV-6 was restricted to IgG1, whereas HHV-7 IgG subclasses included two groups, one restricted only to IgG1 and the other to IgG1 and IgG3. These results demonstrate the differences between HHV-6 and HHV-7 DNA range detection in saliva and plasma samples, as well as the IgG subclass patterns for each virus type, in healthy persons in Argentina.

Human herpesvirus-7 in Brazilian liver transplant recipients: a follow-up comparison between molecular and immunological assays.

Human herpesvirus-6 and -7 (HHV-6, HHV-7) remain latent after primary infection and can reactivate after transplantation. HHV-6 active infection has been related to some clinical manifestation, but the role of HHV-7 remains unclear. The clinical significance of HHV-7 DNAemia is not completely known and the immune response against HHV-7 has been poorly studied in transplantation. In this study, we investigated HHV-7 DNAemia in liver transplant recipients and evaluated the immunoglobulin (Ig) G and IgM response against HHV-7. A total of 22 adult liver transplant recipients were followed up for 90 days. HHV-7 DNAemia was detected by nested polymerase chain reaction (PCR) in DNA extracted from sera. IgG and IgM detection was performed by immunofluorescent assay using HHV-7-infected cord blood mononuclear cells. A significant virus antibody response was defined as either a positive IgM or a > or =4-fold rise in the virus IgG antibody. All patients had pre-transplant HHV-7-positive serostatus. Nine of 22 (40.9%) patients presented HHV-7 DNAemia during follow-up. All these patients had anti-HHV-7-positive IgM and/or significant increase in IgG titers with concurrent or subsequent DNAemia. In patients without DNAemia and low persistent IgG antibody titers, IgM was not detected. Correlation between nested PCR and IgM detection was statistically significant (P=0.01). Our study indicates that nested PCR in DNA extraction from serum can be useful to detect and monitor HHV-7 active infection in liver transplant recipients. IgM antibody detection also can be useful as a first immunological technique to detect active infection, especially if combined with PCR.

Detection of human herpesvirus-7 by qualitative nested-PCR: comparison between healthy individuals and liver transplant recipients.

Diagnosis of human herpesvirus-7 active infection in transplant patients has proved difficult, because this virus is ubiquitous and can cause persistent infections in the host. The significance of viral DNA detected in leukocytes by PCR is unclear and cross-reaction in serological tests may occur. This study aimed to evaluate nested-PCR to detect human herpesvirus-7 active infection in liver transplant recipients compared to healthy individuals. human herpesvirus-7 nested-PCR was performed on leukocytes and sera of 53 healthy volunteers and sera of 29 liver transplant recipients. In healthy volunteers, human herpesvirus-7 was detected in 28.3% of leukocytes and 0% of serum. human herpesvirus-7 was detected in sera of 48.2% of the liver transplant recipients. Nested-PCR on DNA extracted from leukocytes detected latent infection and the study suggests that nested-PCR performed on serum could be useful to detect human herpesvirus-7 active infection in liver transplant recipients.

Detection and monitoring of human herpesvirus 7 in adult liver transplant patients: impact on clinical course and association with cytomegalovirus.

We herein have described HCMV and HHV-7 detection during the follow-up of 29 adult liver recipients in our transplant unit. For basic immunosuppression, the patients received cyclosporine and symptomatic HCMV infection was treated with gancyclovir. The most prevalent etiology for liver transplantation was hepatitis C or alcohol abuse (45% of patients). The laboratory monitoring to 180 days after transplantation was performed by nested-polymerase chain reaction to HCMV or HHV-7. HCMV DNA was detected in 19/29 of patients (65.5%) and HHV-7 DNA, in 14/29 of patients (48.2%). The time-related appearance of HHV-7 and HCMV DNA differed significantly (P = .02); their detection was considered independent (P = .2). The results showed that few patients remained free of HHV-7 or HCMV after liver transplantation, indicating that most patients were actively infected with more then one virus sequentially and not concurrently. Graft dysfunction, fever, gastrointestinal system abnormalities, and interstitial pneumonitis dominated the clinical pictures. Thirteen of 29 patients (44.8%) developed symptomatic HCMV active infections. The relationship between the detection of HCMV DNA, and HCMV disease development was significant (P = .0004). In HCMV-free patients, no symptoms or significant laboratory findings were linked with HHV-7. However, HHV-7 was frequently detected sequentially after HCMV, and an interaction of HCMV and/or HHV-6 to increase their pathogenic effects could not be excluded. Further studies should be performed including HHV-6 to evaluate the relationship, among beta herpesviruses.

Congenital infections with human herpesvirus 6 (HHV6) and human herpesvirus 7 (HHV7).

OBJECTIVE: To examine whether: (1) congenital human herpesvirus 6 (HHV6) and human herpesvirus 7 (HHV7) infections occur; whether (2) their manifestations differ from postnatal infections; and whether (3) HHV6 and HHV7 infections differ despite their close relatedness. STUDY DESIGN: HHV6 and HHV7 infections acquired congenitally and postnatally in normal children were compared using viral isolation, serology, reverse-transcription polymerase chain reaction (RT-PCR) and nested DNA-PCR for HHV6 variant A (HHV6A), HHV6 variant B (HHV6B), and HHV7. RESULTS: HHV6 DNA was detected in 57 (1%) of 5638 cord bloods. HHV7 DNA, however, was not detected in 2129 cord bloods. Congenital HHV6 infections differed from postnatal infections, which were acute febrile illnesses. Congenital infections were asymptomatic, 10% demonstrated reactivation at birth, and HHV6 DNA persistence in follow-up blood samples was significantly more frequent. One-third of congenital infections were HHV6A, whereas all postnatal infections were HHV6B. CONCLUSIONS: Congenital HHV6 infections occurred in 1% of births, similar to the rate for cytomegalovirus infection. Congenital infections were clinically and virologically distinct from postnatal infections. Congenital HHV7 infections, however, were not detected, suggesting considerable differences in transmission and pathogenesis in these closely related beta-herpesviruses.

Human herpesvirus 6 (HHV6) DNA persistence and reactivation in healthy children.

OBJECTIVE: To determine in healthy children after primary infection the persistence of human herpesvirus 6 (HHV6) DNA, the presence and frequency of HHV6 re-activation or re-infection, and the relationship of both to illness and the presence of human herpesvirus 7 (HHV7) infection. STUDY DESIGN: Children 1 to 12 years of age with previous HHV6 infection were prospectively evaluated by HHV6 and HHV7 DNA polymerase chain reaction (PCR) and reverse transcription (RT)-PCR for HHV6. HHV6 plasma antibody titers were measured. Illnesses were recorded by diary, and physician records were reviewed. RESULTS: HHV6 DNA was detected in >or=1 peripheral blood mononuclear cell (PBMC) samples in 89% of children. HHV6 reactivation and re-infection were detected by RT-PCR in 1.1% of samples. Detection of HHV6 DNA was intermittent in 76% of children and was not associated with cumulative rates of illness. Illness at a study visit was significantly associated with the absence of HHV6 and HHV7 DNA in PBMC samples and was not associated with HHV6 antibody titer or the presence of HHV6 DNA in saliva. CONCLUSIONS: HHV6 DNA persists in most children intermittently following primary infection and is unrelated to illness. Reactivation of HHV6 occurs in healthy children without apparent illness.

Human herpesvirus-7 as a cause of exanthematous ilnesses in Belém, Pará, Brazil.

We screened sera from 370 patients suffering from exanthematous illnesses in Belém, North Brazil, for the presence of human herpesvirus-7 (HHV-7) IgM and IgG antibodies. Samples were obtained from January 1996 to December 2002 and were processed by a HHV-7-specific indirect immunofluorescence assay (IFA). HHV-7-specific IgM and/or IgG antibodies were found in 190 (51.4%) of these patients, with similar prevalence rates (IgM+ and IgG+ subgroups taken together) for female and male subjects: 52.5% and 50.3%, respectively. Serological status as defined by IgG was identified in 135 (36.5%) patients. In 55 (14.9%) of the patients HHV-7 IgM antibodies were detected. HHV-7 IgM- and- IgG antibody rates were similar (p > 0.05) when male and female subjects are compared: 14.4% versus 15.3% and 38.1% versus 35.0%, respectively. Statistically significant difference (p = 0.003) was noted when HHV-7-IgM-positive female and male patients aged 5-8 months are compared. Prevalence rates ranging from 4.6% (female, 5-8 months of age) to 93.3% (female, > 10 years of age) and 12.2% (male, 5-8 months) to 80.0% (male, 8-10 years of age) were noted in the IgG- positive subgroups. A subgroup (n = 131) of patients with IgM or IgG HHV-7 antibodies were examined for the presence of DNA using a polymerase chain reaction/nested PCR. Recent/active HHV-7 infection occurred at a rate of 11.0% (6/55) among patients whose samples presented IgM+ specific antibodies. In a subgroup (n = 76) of patients with high HHV-7-IgG antibody levels (titre > 1:160) DNA could not be detected in sera examined by PCR/nested PCR. Of the six recent/active infections, four subjects with less than 1 year and two with 3 and 6 years of age, presented typical exanthem subitum (E.S), as defined by higher fever (> 38.0 degrees C) with duration of 24 to 72 hours, followed by a maculopapular skin rash. Our results underscore the need for searching HHV-7 infection in patients with exanthematous diseases, particularly those presenting with typical E.S. HHV-7 appears therefore to emerge as a newly recognized pathogen of exanthem in our region.

Definition and distribution analysis of glycoprotein B gene alleles of human herpesvirus 7.

As for other herpesviruses, glycoprotein B (gB) of human herpesvirus 7 (HHV-7) is believed to play a major role in virus infection and as a target of the host immunogenic response. Using nested PCR, we amplified the whole HHV-7 gB gene from 108 human peripheral blood mononuclear cell samples and studied its variability. By means of restriction fragment length polymorphism (RFLP) analysis, three distinct patterns, designated I, II, and III, were defined and detected at frequencies of 93, 5, and 2%, respectively. Determination of the nucleotide sequence allowed us to recognize five critical positions in the gB gene with six specific combinations of point changes at these positions. These combinations were gB alleles A, B, C, D, E, and F. Alleles D and E corresponded to RFLP patterns II and III, respectively, while the other four alleles corresponded to RFLP pattern I. Identical gB alleles were detected in serial samples as well as in paired samples of blood and saliva from the same individuals, except for one case. In contrast, the distribution of gB alleles differed according to the geographical origin of the human samples: C was the most frequent allele in both African and Caribbean samples, whereas F was the most frequent allele in European ones. Although none of the allele-specific nucleotide changes induced any modification at the protein level, the definition of gB alleles provided convenient viral markers for the study of both HHV-7 infections and human population genetics.

Primary human herpesvirus 7 infection: a comparison of human herpesvirus 7 and human herpesvirus 6 infections in children.

OBJECTIVE: To define the clinical and virologic characteristics of primary human herpesvirus 7 (HHV-7) infection and to compare these characteristics with those of primary human herpesvirus 6 (HHV-6) infection. STUDY DESIGN: A prospective convenience sample study of 496 children < or =3 years old. HHV-7 and HHV-6 infections were identified by viral isolation. Polymerase chain reaction and serology for HHV-7 and HHV-6 were performed. Clinical and laboratory characteristics of patients were obtained from medical records and follow-up interviews. RESULTS: Children with primary HHV-7 infection (n = 8) were identified and compared with children with primary HHV-6 infection (n = 29) detected during the same time period. All children were febrile (mean temperature 39.8 degrees C) with no difference in the degree of fever, frequency of rash, or gastrointestinal complications between the groups. The median age of children with primary HHV-7 infection was 26 months, significantly older than that of children with primary HHV-6 infection (median, 9 months). Children with primary HHV-7 infection were also more likely than those with primary HHV-6 infection to have seizures associated with the illness (P = .004). CONCLUSION: Primary infection with HHV-7 can cause a highly febrile illness in childhood, complicated by seizures. The serologic diagnosis of primary HHV-6 and HHV-7 infections may be confounded by cross-reacting antibodies.

Human herpesvirus 7 infection associated with central nervous system manifestations.

The clinical features of infection with human herpesvirus 7 (HHV-7) are not well described. Exanthem subitum is the only illness that is confirmed to be caused by HHV-7. We report two children who had exanthem subitum associated with central nervous system manifestations. Two strains of HHV-7 were isolated sequentially from peripheral blood mononuclear cells and saliva of the some child who had exanthem subitum complicated with acute hemiplegia in childhood. Two strains were confirmed to be HHV-7 by means of monoclonal antibodies to human herpesvirus 6 (HHV-6) and HHV-7, polymerase chain reaction, and DNA analysis. During the convalescent period, the antibody titer to HHV-7 rose from less than 1:10 to 1:320, whereas the antibody titer to HHV-6 remained less than 1:10. Another child with exanthem subitum complicated by acute hemiplegia had serologic evidence of primary HHV-7 infection. These two cases demonstrate a new relationship between HHV-7 and central nervous system symptoms.

Prevalencia del virus humano herpes 7 en donadores de sangre mexicanos / Prevalence of human herpes viruz 7 in Mexican blood donors

El herpes virus humano 7 (HHV-7) fue aislado recientemente de las células CD4 de individuos sanos; actualmente se realizan estudios de suposible asociación con enfermedades de humanos. Se estudiaron 200 muestras de sangre de candidatos a donadores asintomáticos del banco de sangre del Hospital General de México, utilizando la prueba de inmunofluorescencia indirecta (IFA) en células SupT1 infectadas con el HHV-7 en la Universidad de Colonia, Alemania. El 83.5 por ciento de las muestras fueron de varones y el 16.5 por ciento de mujeres; provenían de 12 diferentes estados de la república mexicana con predominio del Distrito Federal (60.5 por ciento) y del Estado de México (28 por ciento) con edad promedio de 29.2 años. El HHV-7 fue detectado en el 98.5 por ciento de los casos a diferentes titulaciones; el 84.5 por ciento presentó títulos elevados (ò 1:80). El 1 por ciento resultó positivo a hepatitis B, el 2 por ciento a sífilis, y el 0.5 por ciento a brucella. Todos fueron negativos a hepatitis C así como al VIH. La elevada prevalencia de HHV-7 deberá aclararse en investigaciones futuras que permitan determinar la posible asociación de títulos altos con infección activa, así como el significado de ésta en relación a enfermedad