Diagnosis of human herpesvirus 6B primary infection by polymerase chain reaction in young children with exanthematic disease

Abstract

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.

Frequency evaluation and molecular characterization of HHV‐6 and HHV‐7 among children under 5 years with fever and skin rash

“…Human Herpesvirus 6 and 7 (HHV‐6 and HHV‐7) are classified in Betaherpesvirena and Roseola virus genus 1,2 . For the first time, HHV‐6 was isolated from AIDS patients and was cultured in T cell culture in 1986 3,4 . Four years later, HHV‐7 was isolated from a healthy blood donor's peripheral blood lymphocytes 5 .…”

“…Primary infections with clinical symptoms in approximately 30% of children are known as roseola or exanthema subitum 9 . Exanthema is a classic early childhood disease with sudden onset of high fever, which lasts 3 to 4 days, and rashes appear as the baby's temperature decreases 3,5 . HHV‐7 is also the cause of about 5%–10% of roseola cases 3,6,10 .…”

“…9 Exanthema is a classic early childhood disease with sudden onset of high fever, which lasts 3 to 4 days, and rashes appear as the baby's temperature decreases. 3,5 HHV-7 is also the cause of about 5%-10% of roseola cases. 3,6,10 HHV-6A is not yet known as a specific disease agent.…”

“…3,5 HHV-7 is also the cause of about 5%-10% of roseola cases. 3,6,10 HHV-6A is not yet known as a specific disease agent. 3,6 Both variants of HHV-6 are related to neurological diseases, although they have different tropisms and pathogenicity.…”

Optimisation of a quantitative polymerase chain reaction-based strategy for the detection and quantification of human herpesvirus 6 DNA in patients undergoing allogeneic haematopoietic stem cell transplantation

“…In Brazil, the first population-based study reporting the prevalence of HHV-6 antibodies was performed by Linhares et al (1991) , who found rates of 76.5% for Brazilians and 77.2% for Japanese immigrants. Since then, studies on HHV-6 seroprevalence and DNA detection (SybrGreen ® based technology) have been reported in solid organ transplant recipients ( de Freitas et al 1994 , de Freitas & Linhares 1997, Oliveira et al 2001 , Canto et al 2008 , Cavalcanti 2011 , Magalhães et al 2011 , Guardia et al 2012 , 20, 2014 ), but the detection by real-time quantitative polymerase chain reaction (qPCR) (TaqMan ® technology based) in HSCT recipients has not been systematically performed in Brazilian patients. The development of diagnostics and immunology methods for HHV-6 detection can provide better surveillance of HHV-6 reactivation ( de Pagter et al 2008b , 2010, Betts et al 2011 , Gerdemann et al 2013 , Leibovitch et al 2014) .…”