Clinical Characteristics of Primary HHV-6B Infection in Children Visiting the Emergency Room. Issue 10 (October 2019)

• Record Type: Journal Article
• Authors: Hattori, Fumihiko; Kawamura, Yoshiki; Kozawa, Kei; Miura, Hiroki; Miyake, Misa; Yoshikawa, Akiko; Ihira, Masaru; Yoshikawa, Tetsushi
• Is Part Of: Pediatric infectious disease journal. Volume 38:Issue 10(2019)
• Publication Date: 2019-10
• Subjects: exanthema subitem -- febrile seizure -- real-time PCR; Communicable diseases in children -- Periodicals; Infection in children -- Periodicals; 618.929
• DOI: 10.1097/INF.0000000000002379
• Languages: English
• ISSNs: 0891-3668

Abstract

Abstract : Objective: This cohort study, based on the design of a prior study in the United States, was conducted to elucidate the clinical features of primary human herpesvirus-6B (HHV-6B) infection. Methods: Between June 2014 and May 2016, febrile children younger than 5 years who visited the emergency room (ER) and underwent blood examination were enrolled in this study. Results: Fifty-nine (12%) of the 491 patients were diagnosed with primary HHV-6B infection. The rates of both simple and complex febrile seizure were significantly higher in patients with primary HHV-6B infection than in those without ( P < 0.001 and P = 0.008, respectively). The median age at primary HHV-6B infection was 15 months. Forty-seven (79.7%) of the 59 patients with primary HHV-6B infection were younger than 2-year-old. Clinical features were compared between HHV-6B–infected patients older and younger than 2 years. The frequency of apparent infection (exanthema subitum) was significantly higher in the younger patients ( P = 0.01). The median leukocyte ( P = 0.01) and lymphocyte ( P < 0.001) counts in the patients older than 2 years were significantly lower than those in the younger patients. Conclusions: Primary HHV-6B infection accounted for 12% of ER visits. Secondary febrile seizures, in particular the complex type, were considered to be a major contributor to the disease burden of primary HHV-6B infection. The timing of primary HHV-6B infection occurred at older ages than in past reports, and the frequency of inapparent infection was higher in older patients.