Pediatric Clinic, IRCCS Policlinico San Matteo Foundation, Pavia, Italy.
Molecular Virology Unit, Department of Diagnostic Medicine, IRCCS Policlinico San Matteo Foundation, Pavia, Italy.
Acta Biomed. 2022 Mar 21;92(S4):e2021415. doi: 10.23750/abm.v92iS4.12664.
Primary HHV7 infection is almost ubiquitous, and it can present as exanthema subitem. Little is known on the clinical relevance of HHV7 neuroinvasion in immunocompetent children.
We describe 12 patients (median age 9.45 years, 50% males) with acute encephalopathy and active HHV7 infection. In all patients, HHV7-DNA was detected on cerebrospinal fluid (CSF) by RT-PCR.
7/12 patients had meningoencephalitis (two with ADEM and one with MOG antibody-associated CIS); 5/12 showed acute neuropsychiatric symptoms. EEG showed anomalies exclusively in patients with meningoencephalitis. Six patients had RMN anomalies. CSF HHV7 copies ranged between 20 and 3,500 copies/mL (median 66 copies/mL) and mean HHV7 CSF/blood ratio was 0.75. Outcome was favorable in all children, although 3/12 had minor neurobehavioral sequelae. Mean follow-up period of 5.2 months.
HHV7 can determine neuroinvasion in immunocompetent children, leading to acute encephalopathy. Blood-brain barrier damage and high CSF/blood viral copies ratio correlated with a more severe presentation. We speculate on the importance of immune-mediated mechanisms in provoking clinical features.
原发性 HHV7 感染几乎无处不在，它可能表现为出疹。关于免疫功能正常的儿童中 HHV7 神经入侵的临床相关性知之甚少。
我们描述了 12 例急性脑病和活动性 HHV7 感染的患者（中位年龄 9.45 岁，50%为男性）。在所有患者中，通过 RT-PCR 在脑脊液（CSF）中检测到 HHV7-DNA。
12 例患者中有 7 例（2 例伴有 ADEM，1 例伴有 MOG 抗体相关 CIS）患有脑膜炎脑炎；5 例表现为急性神经精神症状。脑电图异常仅见于脑膜炎脑炎患者。6 例患者存在 RMN 异常。CSF HHV7 拷贝数在 20 至 3500 拷贝/毫升之间（中位数 66 拷贝/毫升），HHV7 CSF/血比值平均为 0.75。所有患儿的预后均良好，尽管 3 例患儿存在轻微的神经行为后遗症。平均随访时间为 5.2 个月。
HHV7 可导致免疫功能正常的儿童发生神经入侵，导致急性脑病。血脑屏障损伤和高 CSF/血病毒拷贝数比值与更严重的表现相关。我们推测免疫介导机制在引发临床特征方面的重要性。
