RESUMO
An immunocompetent toddler came to medication attention with gastroenteritis, complicated by encephalopathy and hepatitis. Multiplexed testing using a polymerase chain reaction meningitis panel was positive for human herpesvirus 6 (HHV-6). Clinical correlation, quantitative HHV-6 polymerase chain reaction, and metagenomic next-generation sequencing supported a likely diagnosis of primary HHV-6B infection.
Assuntos
Encefalopatias/virologia , Exantema Súbito/virologia , Gastroenterite/virologia , Hepatite/virologia , Herpesvirus Humano 6/isolamento & purificação , Reação em Cadeia da Polimerase Multiplex , Herpesvirus Humano 6/genética , Humanos , Imunocompetência , Lactente , Masculino , Medição de RiscoRESUMO
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.
Assuntos
DNA Viral/análise , Exantema Súbito/virologia , Herpesvirus Humano 7/isolamento & purificação , Brasil/epidemiologia , Pré-Escolar , Exantema Súbito/diagnóstico , Exantema Súbito/epidemiologia , Herpesvirus Humano 7/genética , Humanos , Reação em Cadeia da Polimerase , PrevalênciaRESUMO
INTRODUCTION: Exanthem subitum is a classical rash disease of early childhood caused by human herpesvirus 6B (HHV-6B). However, the rash is frequently misdiagnosed as that of either measles or rubella. METHODS: In this study, a nested multiplex polymerase chain reaction (PCR) was used to diagnose HHV-6B primary infection, differentiate it from infections caused by HHV-6A and compare it to antibody avidity tests. The samples were separated into case group and control group according to the results of the indirect immunofluorescence assay (IFA) technique. RESULTS: From the saliva samples analyzed, HHV-6A DNA was detected in 3.2 percent of the case group and in 2.6 percent of the control group. Regarding HHV-6B, PCR detected viral DNA in 4.8 percent of the case group and in 1.3 percent of the control group. Among the serum samples studied, a frequency of 1.7 percent was determined for HHV-6A in the case group and 1.2 percent in the control group. PCR did not detect HHV-6B DNA in serum samples. The sensitivity and specificity of the PCR technique ranged from 0 percent to 4.8 percent and 97.5 percent to 100 percent, respectively, compared to IFA. CONCLUSIONS: The PCR technique was not suitable for diagnosing primary infection by HHV-6B in children with exanthematic disease and should not substitute the IFA.
INTRODUÇÃO: O exantema súbito é uma doença comum durante a infância e pode ser causada pela infecção por herpesvirus humano tipo 6B (HHV-6B). No entanto, a erupção cutânea característica dessa doença, é frequentemente confundida com outras viroses como sarampo ou rubéola. MÉTODOS: Foi utilizada a técnica de reação em cadeia da polimerase (PCR) no formato nested multiplex para o diagnóstico de infecção primária por HHV-6B, diferenciação entre as infecções causadas pelo HHV-6A e comparação com testes de avidez de anticorpos. As amostras foram separadas em grupo caso e grupo controle, de acordo com os resultados do teste de imunofluorescência indireta (IFA). RESULTADOS: Nas amostras de saliva analisadas, o DNA do HHV-6A foi detectado em 3,2 por cento no grupo caso e em 2,6 por cento das amostras do grupo controle. Em relação ao HHV-6B, o DNA viral foi observado em 4,8 por cento no grupo caso e em 1,3 por cento no grupo controle. Após a realização da PCR nas amostras de soro, o DNA do HHV-6A foi detectado em 1,7 por cento no grupo caso e em 1,2 por cento no grupo controle, enquanto o DNA do HHV-6B não foi detectado. A sensibilidade e a especificidade da técnica de PCR variaram de 0 por cento a 4,8 por cento e de 97,5 por cento a 100 por cento, respectivamente, quando comparado com a IFA. CONCLUSÕES: A técnica de PCR não se mostrou adequada para o diagnóstico de infecção primária pelo HHV-6B em crianças com doença exantemática e não deve substituir a IFA.
Assuntos
Criança , Humanos , Anticorpos Antivirais/sangue , DNA Viral/análise , Exantema Súbito/diagnóstico , /genética , Afinidade de Anticorpos , Diagnóstico Diferencial , Exantema Súbito/virologia , Técnica Indireta de Fluorescência para Anticorpo , /imunologia , Reação em Cadeia da Polimerase/métodos , Sensibilidade e Especificidade , Saliva/virologiaRESUMO
INTRODUCTION: Exanthem subitum is a classical rash disease of early childhood caused by human herpesvirus 6B (HHV-6B). However, the rash is frequently misdiagnosed as that of either measles or rubella. METHODS: In this study, a nested multiplex polymerase chain reaction (PCR) was used to diagnose HHV-6B primary infection, differentiate it from infections caused by HHV-6A and compare it to antibody avidity tests. The samples were separated into case group and control group according to the results of the indirect immunofluorescence assay (IFA) technique. RESULTS: From the saliva samples analyzed, HHV-6A DNA was detected in 3.2% of the case group and in 2.6% of the control group. Regarding HHV-6B, PCR detected viral DNA in 4.8% of the case group and in 1.3% of the control group. Among the serum samples studied, a frequency of 1.7% was determined for HHV-6A in the case group and 1.2% in the control group. PCR did not detect HHV-6B DNA in serum samples. The sensitivity and specificity of the PCR technique ranged from 0% to 4.8% and 97.5% to 100%, respectively, compared to IFA. CONCLUSIONS: The PCR technique was not suitable for diagnosing primary infection by HHV-6B in children with exanthematic disease and should not substitute the IFA.
Assuntos
Anticorpos Antivirais/sangue , DNA Viral/análise , Exantema Súbito/diagnóstico , Herpesvirus Humano 6/genética , Afinidade de Anticorpos , Criança , Diagnóstico Diferencial , Exantema Súbito/virologia , Técnica Indireta de Fluorescência para Anticorpo , Herpesvirus Humano 6/imunologia , Humanos , Reação em Cadeia da Polimerase/métodos , Saliva/virologia , Sensibilidade e EspecificidadeRESUMO
BACKGROUND: Human herpesvirus type 6 (HHV-6) has been shown to infect almost all children by 4 years of age. Primary infection causes an undifferentiated febrile illness, with approximately 30% of children exhibiting the classic clinical manifestations of exanthem subitum. Even with typical clinical presentation, exanthem subitum is frequently misdiagnosed as measles or rubella. Our aim was to describe the frequency and clinical manifestations of HHV-6 infection in children less than 4 years of age enrolled in a study designed to define the etiology of rash diseases. PATIENTS AND METHODS: The study was conducted between January 1998 and December 2006 at a general hospital and a large primary health care unit from Niterói, Rio de Janeiro, Brazil. Sera from 223 children, in whom measles, rubella, dengue fever, and parvovirus B19 infections were excluded, were studied for anti-HHV-6 antibodies using an indirect immunofluorescence test. Demographic and clinical data of those patients were described. RESULTS: Ninety-seven (43.5%) of the children had evidence of primary HHV-6 infection. The age of onset peaked at 6-11 months and 75% of the HHV-6 infection occurred in children between 6 and 17 months. Only 21% of the HHV-6 cases had a typical roseola-like illness and 73% and 46%, respectively, fulfilled the clinical criteria of measles and rubella suspected case. CONCLUSIONS: Our study confirms the importance of HHV-6 infection in young children and highlights the difficulties of diagnosing a rash illness on clinical grounds alone.
Assuntos
Exantema Súbito/epidemiologia , Exantema Súbito/virologia , Herpesvirus Humano 6/isolamento & purificação , Infecções por Roseolovirus/epidemiologia , Infecções por Roseolovirus/virologia , Anticorpos Antivirais/sangue , Brasil/epidemiologia , Pré-Escolar , Exantema Súbito/diagnóstico , Feminino , Técnica Indireta de Fluorescência para Anticorpo , Humanos , Lactente , Masculino , Sarampo/diagnóstico , Infecções por Roseolovirus/diagnóstico , Rubéola (Sarampo Alemão)/diagnóstico , Estudos SoroepidemiológicosRESUMO
BACKGROUND: Parvovirus B19 infections are associated with different clinical manifestations that vary from symptom-less to severe. The main clinical manifestations are erythema infectiosum or fifth disease, transient aplastic crisis in individuals with hemoglobinopathies, chronic anemia in the immunocompromised, acute polyarthralgia syndrome in adults, hydrops fetalis, spontaneous abortion and stillbirth. Although the classical features of B19 and rubella infections are distinct, uncommon presentations can lead to misdiagnosis. OBJECTIVE: The goal of this study was to assess the occurrence of parvovirus B19 (B19) infection in patients with clinical signs of toxoplasmosis or rubella, both of which were not confirmed by laboratorial techniques. STUDY DESIGN: Serum samples from 214 patients were collected between January 1996 and December 1997 in the state of Rio de Janeiro, Brazil, B19 specific IgG and IgM were detected by using commercial enzyme-linked immunosorbent assays (ELISA), and viral nucleic acid was detected employing a nested polymerase chain reaction (PCR) protocol. RESULTS: Combining the results obtained by IgM ELISA and PCR, 14.5% of the samples were positive in one or both tests, with a concordance of 92.5% between the two techniques. CONCLUSIONS: Specimens collected in 16 out of 22 municipalities were positive in at least one out of the three tests employed, indicating that parvovirus B19 circulates in several regions of the state of Rio de Janeiro.
Assuntos
Infecções por Parvoviridae/virologia , Parvovirus B19 Humano/isolamento & purificação , Aborto Espontâneo/virologia , Adolescente , Adulto , Anticorpos Antivirais/sangue , Brasil , Criança , Pré-Escolar , DNA Viral/análise , Ensaio de Imunoadsorção Enzimática , Exantema Súbito/virologia , Feminino , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Lactente , Masculino , Pessoa de Meia-Idade , Infecções por Parvoviridae/fisiopatologia , Parvovirus B19 Humano/genética , Parvovirus B19 Humano/imunologia , Reação em Cadeia da Polimerase , GravidezRESUMO
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.
Assuntos
Encefalopatias/virologia , Infecções por Herpesviridae/patologia , Herpesvirus Humano 7 , Anticorpos Antivirais/análise , Encefalopatias/patologia , DNA Viral/análise , Epilepsia Generalizada/virologia , Epilepsia Tônico-Clônica/virologia , Exantema Súbito/patologia , Exantema Súbito/virologia , Feminino , Hemiplegia/virologia , Herpesvirus Humano 6/genética , Herpesvirus Humano 6/imunologia , Herpesvirus Humano 6/isolamento & purificação , Herpesvirus Humano 7/genética , Herpesvirus Humano 7/imunologia , Herpesvirus Humano 7/isolamento & purificação , Humanos , Lactente , Leucócitos Mononucleares/virologia , Reação em Cadeia da Polimerase , Saliva/virologiaRESUMO
Recent human herpesvirus 6 (HHV-6) infection was detected in cases of exanthem subitum (ES) involving four children, aged 10 to 24 months, between April and August 1994, in Belém, Brazil. By using the indirect immunofluorescence antibody assay (IFA), significant increases (at least eight times) in antibody concentrations were noted from the acute to the convalescent serum samples, with titers ranging from < 1:10/1:80 to < 1:10/1:640 (patients 3 and 2, respectively). All children had high fever (over 39 degrees C) for three days, followed by generalized, maculo-papular skin rash. A physical examination of the children also revealed concomitant, cervical lymph node swelling and tonsillar pharyngitis in two of them.
Assuntos
Anticorpos Antivirais/sangue , Exantema Súbito/virologia , Herpesvirus Humano 6/imunologia , Brasil , Pré-Escolar , Exantema Súbito/diagnóstico , Feminino , Técnica Indireta de Fluorescência para Anticorpo , Humanos , Lactente , MasculinoRESUMO
We evaluated febrile convulsions prospectively in 42 children to investigate the association between acute human herpesvirus-6 (HHV-6) infection and first-time febrile convulsions, using both virologic and serologic methods. Eight children had primary HHV-6 infection documented by viral culture and an additional three by acute- and convalescent-phase serologic studies. These findings indicate that acute HHV-6 infection is a frequent cause of febrile convulsions in young children.