{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,27]],"date-time":"2026-08-27T16:44:32Z","timestamp":1787849072997,"version":"build-2784847793"},"reference-count":21,"publisher":"MDPI AG","issue":"16","license":[{"start":{"date-parts":[[2024,8,8]],"date-time":"2024-08-08T00:00:00Z","timestamp":1723075200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"University of Medicine and Pharmacy Carol Davila"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["JCM"],"abstract":"<jats:p>Background: Human herpesvirus 6 (HHV-6) is considered a ubiquitous virus, with many countries reporting a seroprevalence of more than 80\u201390% among the general population. However, this virus is unique among herpesviruses in its ability to integrate into the genetic material of the host\u2019s cells. Thus, there are three ways by which HHV-6 can cause an active infection\u2013primary infection, reactivation of a latent acquired infection, or activation of iciHHV-6 (inherited chromosomally integrated HHV-6). Whole blood quantitative polymerase chain reaction (qPCR) is very useful in distinguishing between iciHHV-6 and primary infection\/reactivation. Our aim is to assess the role of HHV-6 in the aetiology of central nervous system (CNS) infections in adults and children, to describe all HHV-6-positive cases in an attempt to determine the susceptible population and to identify potential risk factors that can be linked to HHV-6 meningoencephalitis. Methods: We performed a retrospective study involving patients that were admitted to Prof. Dr. Matei Bals National Institute of Infectious Diseases, Bucharest, Romania, with a diagnosis of meningitis or encephalitis. We only selected the clinical records of patients that had a multiplex PCR Biofire\u00ae FilmArray\u00ae meningitis\/encephalitis panel. Results: We report a 5% HHV-6 positivity in the cerebrospinal fluid (CSF) of patients with CNS infections tested with a commercial multiplex PCR M\/E (meningitis\/encephalitis) panel. Additionally, 2% to 4% of the total study population (n = 100) had active HHV-6 infections, which denotes 40 to 80% of the HHV-6-positive samples. We did not observe any statistically significant correlation between HHV-6 positivity in the CSF and variables such as age, sex, or comorbidities, including obesity, diabetes, hypertension, immunosuppression, or oncologic disease. Therefore, no risk factors could be linked with HHV-6 positivity in the CSF. Conclusions: although multiplex qualitative PCR is highly useful for providing rapid results and identifying nearly every pathogen that can cause meningitis\/encephalitis, we have to be aware of this type of test\u2019s limitations. All patients with HHV-6 detectable in their CSF via a multiplex PCR test should also undergo qPCR testing from both CSF and blood to prevent over-diagnosing HHV-6 CNS infections, to avoid unnecessary antiviral treatments, and ensure the accurate identification of the true diagnosis.<\/jats:p>","DOI":"10.3390\/jcm13164660","type":"journal-article","created":{"date-parts":[[2024,8,8]],"date-time":"2024-08-08T12:13:14Z","timestamp":1723119194000},"page":"4660","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["Human Herpesvirus 6\u2014A Rare Aetiologic Agent for CNS Infections in Immunocompetent Individuals or an Underestimation?"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0009-0004-0117-7980","authenticated-orcid":false,"given":"Oana Alexandra","family":"Ganea","sequence":"first","affiliation":[{"name":"Faculty of General Medicine, Department of Infectious Diseases, \u201cCarol Davila\u201d University of Medicine and Pharmacy, Dionisie Lupu Street No. 37, 010458 Bucharest, Romania"},{"name":"\u201cMatei Bals\u201d National Institute of Infectious Diseases, Dr. Calistrat Grozovici Street No. 1, 021105 Bucharest, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"C\u0103t\u0103lin","family":"Tili\u0219can","sequence":"additional","affiliation":[{"name":"Faculty of General Medicine, Department of Infectious Diseases, \u201cCarol Davila\u201d University of Medicine and Pharmacy, Dionisie Lupu Street No. 37, 010458 Bucharest, Romania"},{"name":"\u201cMatei Bals\u201d National Institute of Infectious Diseases, Dr. Calistrat Grozovici Street No. 1, 021105 Bucharest, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anca","family":"Streinu-Cercel","sequence":"additional","affiliation":[{"name":"Faculty of General Medicine, Department of Infectious Diseases, \u201cCarol Davila\u201d University of Medicine and Pharmacy, Dionisie Lupu Street No. 37, 010458 Bucharest, Romania"},{"name":"\u201cMatei Bals\u201d National Institute of Infectious Diseases, Dr. Calistrat Grozovici Street No. 1, 021105 Bucharest, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4118-8268","authenticated-orcid":false,"given":"Daniela","family":"Pi\u021bigoi","sequence":"additional","affiliation":[{"name":"Faculty of General Medicine, Department of Infectious Diseases, \u201cCarol Davila\u201d University of Medicine and Pharmacy, Dionisie Lupu Street No. 37, 010458 Bucharest, Romania"},{"name":"\u201cMatei Bals\u201d National Institute of Infectious Diseases, Dr. Calistrat Grozovici Street No. 1, 021105 Bucharest, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anca Cristina","family":"Dr\u0103g\u0103nescu","sequence":"additional","affiliation":[{"name":"\u201cMatei Bals\u201d National Institute of Infectious Diseases, Dr. Calistrat Grozovici Street No. 1, 021105 Bucharest, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mihai","family":"Lazar","sequence":"additional","affiliation":[{"name":"Faculty of General Medicine, Department of Infectious Diseases, \u201cCarol Davila\u201d University of Medicine and Pharmacy, Dionisie Lupu Street No. 37, 010458 Bucharest, Romania"},{"name":"\u201cMatei Bals\u201d National Institute of Infectious Diseases, Dr. Calistrat Grozovici Street No. 1, 021105 Bucharest, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nicoleta","family":"Mihai","sequence":"additional","affiliation":[{"name":"Faculty of General Medicine, Department of Infectious Diseases, \u201cCarol Davila\u201d University of Medicine and Pharmacy, Dionisie Lupu Street No. 37, 010458 Bucharest, Romania"},{"name":"\u201cMatei Bals\u201d National Institute of Infectious Diseases, Dr. Calistrat Grozovici Street No. 1, 021105 Bucharest, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Drago\u0219","family":"Florea","sequence":"additional","affiliation":[{"name":"Faculty of General Medicine, Department of Infectious Diseases, \u201cCarol Davila\u201d University of Medicine and Pharmacy, Dionisie Lupu Street No. 37, 010458 Bucharest, Romania"},{"name":"\u201cMatei Bals\u201d National Institute of Infectious Diseases, Dr. Calistrat Grozovici Street No. 1, 021105 Bucharest, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sorin \u0218tefan","family":"Aram\u0103","sequence":"additional","affiliation":[{"name":"Faculty of General Medicine, Department of Infectious Diseases, \u201cCarol Davila\u201d University of Medicine and Pharmacy, Dionisie Lupu Street No. 37, 010458 Bucharest, Romania"},{"name":"\u201cMatei Bals\u201d National Institute of Infectious Diseases, Dr. Calistrat Grozovici Street No. 1, 021105 Bucharest, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1657-3642","authenticated-orcid":false,"given":"Victoria","family":"Aram\u0103","sequence":"additional","affiliation":[{"name":"Faculty of General Medicine, Department of Infectious Diseases, \u201cCarol Davila\u201d University of Medicine and Pharmacy, Dionisie Lupu Street No. 37, 010458 Bucharest, Romania"},{"name":"\u201cMatei Bals\u201d National Institute of Infectious Diseases, Dr. Calistrat Grozovici Street No. 1, 021105 Bucharest, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,8,8]]},"reference":[{"key":"ref_1","first-page":"90","article-title":"Human herpes simplex virus-6 (HHV-6) detection and seroprevalence among Qatari nationals and immigrants residing in Qatar","volume":"2","author":"Zedan","year":"2021","journal-title":"IJID 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