聚合酶链反应诊断单纯疱疹病毒性脑炎

用聚合酶链反应（ＰＣＲ）扩增患者脑脊液（ＣｈＦ）中病毒特异性ＤＮＡ可早期快速诊断单纯疱疹病毒性脑炎（ＨＳＥ）。１９例临床确诊的病毒性脑炎患者，经ＰＣＲ在ＣＳＦ中检出单纯疱疹病毒（ＨＳＶ）１３例，全部阳性标本均经分子杂交证实为ＨＳＶ－ＤＮＡ，而１４例其他神经疾病（ＯＮＤ）对照组均为阴性，显示了这一方法的特异性。其中７例病毒性脑炎ＣＳＦ标本分别用ＰＣＲ分子杂交和病毒分离等三种方法检测ＨＳＶ；显示ＰＣＲ最为敏感。表明ＰＣＲ技术的广泛应用将提高ＨＳＥ的早期诊断水平，指导临床正确治疗。     

The role of laboratory investigation in the diagnosis and management of patients with suspected herpes simplex encephalitis: a consensus report. The EU Concerted Action on Virus Meningitis and Encephalitis.

As effective therapies for the treatment of herpes simplex encephalitis (HSE) have become available, the virology laboratory has acquired a role of primary importance in the early diagnosis and clinical management of this condition. Several studies have shown that the polymerase chain reaction (PCR) of CSF for the detection of herpes simplex virus type 1 (HSV-1) or type 2 (HSV-2) DNA provides a reliable method for determining an aetiological diagnosis of HSE. The use of PCR in combination with the detection of a specific intrathecal antibody response to HSV currently represents the most reliable strategy for the diagnosis and monitoring of the treatment of adult patients with HSE. The use of these techniques has also led to the identification of atypical presentations of HSV infections of the nervous system and permits the investigation of patients who develop a relapse of encephalitic illness after an initial episode of HSE. A strategy for the optimal use of the investigative laboratory in the diagnosis of HSE and subsequent management decisions is described.     

A young patient of acute encephalitis complicated with acyclovir encephalopathy without renal dysfunction]

A previously healthy 30-year-old woman was admitted to our hospital because of impaired consciousness after convulsion. A temporary diagnosis of herpes simplex encephalitis was made, and intravenous acyclovir (ACV) therapy (250 mg four times daily in normal saline over 2 hours) was started. Three days later, she became confused, and was having hallucinations, dysarthria and generalized painful seizures occurred without focal neurologic deficit. Whether the neuropsychiatric symptoms were related to herpes simplex encephalitis or acyclovir neurotoxity was initially unclear. The brain MRI and lumbar puncture findings were initially normal, but abnormal FLAIR lesions appeared later. ACV-associated encephalopathy was considered. ACV was discontinued, and she recovered from the neurological disorder within 24 hours. Although blood levels of acyclovir were not determined, it is unlikely that they were in a toxic range, in view of her normal renal function.     

单纯疱疹病毒脑炎早期诊断方法的研究

】目的探讨单纯疱疹病毒脑炎（ＨＳＥ）早期诊断的最佳方法。方法运用免疫细胞化学（ＩＣＣ）、原位杂交（ＩＳＨ）和聚合酶链式反应（ＰＣＲ）三种方法分别对２６例病理诊断为病毒性脑炎患者的脑组织标本进行检测单纯疱疹病毒（ＨＳＶ）。结果３例标本用ＩＣＣ检测出ＨＳＶ抗原,４例用ＩＳＨ、５例用ＰＣＲ检测出ＨＳＶ核酸,共６例被确诊为ＨＳＥ。结论３种方法均为早期诊断ＨＳＥ的敏感方法,尤以ＰＣＲ最敏感,若联合应用ＩＣＣ和ＰＣＲ是最佳搭配     

巢式聚合酶链反应检测脑脊液中单纯疱疹病毒DNA

应用巢式聚合酶链反应(PCR)检测患者脑脊液(CSF)中单纯疱疹病毒1型(HSV-1)DNA。23例经鞘内HSV-1特异性IgG抗体检测阳性的“HSV-1型性脑炎(HSE)”中19例PCR阳性,4例阴性患者病程均超过1个月。22例IgG阴性的“散发性脑炎”中7例PCR阳性,此7例皆于发病1周内检查CSF,其中2例取材于发病当日。1周后复查7例患者,CSF PCR仍为阳性,IgG皆阴性,提示PCR适用于HSE的早期诊断。     

Immunocytochemical characterization of long-term persistent immune activation in human brain after herpes simplex encephalitis

The clinical, virological and immunocytochemical features of three children who recovered from acute herpes simplex encephalitis (HSE) before the age of 2 years, and who developed secondary severe focal epilepsy after a symptom-free period, leading to neurosurgery 3-10 years later are described. In one child, relapse of HSE occurred immediately after surgery. In all three patients, brain sample biopsies showed abundant CD3-positive T lymphocytes with a majority of CD8 cells, and abundant activated macrophage-microglial cells, a pattern similar to that found in acute HSE. Herpes simplex virus DNA was retrieved from the tissue biopsy in one case. The long-term persistent cerebral inflammatory process observed after HSE differed from that observed in another chronic viral disease, subacute sclerosing panencephalitis. This inflammatory reaction may be a result either of low-grade viral expression or self-induced immune activation. The role of inflammation in triggering epilepsy remains hypothetical. Solving these issues should have major therapeutic implications. Herpes simplex virus DNA latency in brain may be the source of replicative HSE relapse.     

Herpes simplex encephalitis in childhood]

Central nervous system (CNS) infection by herpes simplex virus (HSV) in childhood consists of herpes simplex encephalitis and CNS infections in neonates. Herpes simplex encephalitis in children resembles that in adults, but CNS infections in neonates differs from adult herpes simplex encephalitis in pathogenesis and clinical features. Trans-neuronal transmission by HSV type 1 causes herpes simplex encephalitis both in children and adults, while hematogeneous spread by HSV type 1 or type 2 causes CNS infections in neonates. Mortality of CNS infections by HSV in childhood has been improved since early diagnosis by polymerase chain reaction and anti-viral therapies have been established. However, neurological morbidity has not yet been improved and sometimes HSV infections relapse after the acyclovir therapy. Recently, longer acyclovir therapy with larger doses is recommended for the treatment of CNS infections in childhood.     

Mild form of acute herpes simplex encephalitis in childhood

We describe two patients, aged 3.5 years,and 15 years, with a mild form of herpes simplex encephalitis (HSE). The disease was characterized by convulsions and lymphocytic pleocytosis in the cerebrospinal fluid (CSF). Involvement of herpes simplex virus (HSV) was established by antibody measurements in serum and CSF. Recovery was complete with no antiviral drug administration. It appears that scrutinized serological work-up would widen our concept of mild forms of HSE, with a better prognosis and complete recovery.     

A case of herpes simplex encephalitis diagnosed by polymerase chain reaction]

A case of a 55-year-old male with herpes simplex encephalitis (HSE) was reported. He was admitted because of fever, headache and memory disturbance. T1 weighted MRI showed low signal intensity and T2 weighted imaging revealed high signal intensity in the medial portions of bilateral temporal lobes. Herpes simplex virus (HSV) antibody titer in cerebrospinal fluid (CSF) was not elevated. HSV DNA in CSF was amplified by polymerase chain reaction (PCR) and identified by the microplate hybridization method. The PCR technique would be useful for the diagnosis of HSE.     

Herpes encephalitis during natalizumab treatment in multiple sclerosis

In this case report we describe the first non-fatal herpes simplex virus encephalitis (HSE) case with natalizumab for multiple sclerosis (MS). A 36-year-old woman, previously treated with immunomodulatory and immunosuppressive drugs for MS, developed acute encephalitis after 6 monthly natalizumab perfusions. Brain imaging demonstrated suggestive bi-temporal lesions. Herpes simplex virus type-1 DNA was detected in cerebrospinal fluid. The patient improved gradually after a 21-day course of intravenous acyclovir, but neuropsychiatric changes remained 5 months later. Our non-fatal case of HSE and other reported cases of herpes infections provide evidence of an increased risk with natalizumab and point to the need for clinicians to maintain awareness.     

阿昔洛韦对单纯疱疹病毒脑炎小鼠脑细胞的保护作用

目的 了解单纯疱疹病毒脑炎(HSE)脑细胞结构的改变及药物的影响。方法 采用光学显微镜及透射电子显微镜观察HSE小鼠脑细胞结构的变化，并给予阿昔洛韦(ACV)及地塞米松(DEX)治疗，观察治疗后脑细胞结构的变化。结果 HSE小鼠脑神经细胞明显肿胀，核仁固缩，核内结构破坏，线粒体及高尔基体可见空泡样变性，核仁内可见病毒颗粒。用药物干预的小鼠脑神经细胞改变较轻微，未找到病毒颗粒；与单用ACV干预的小鼠相比，用ACV DEX干预的小鼠脑神经细胞及毛细血管周围水肿明显减轻。结论 HSE早期给予ACV DEX治疗，对HSE脑细胞结构有明显保护作用。     

Herpes simplex encephalitis in North West India.

All patients admitted with provisional diagnosis of an encephalitic illness over a period of 30 months, were studied. Special investigations included CSF analysis, EEG, CT scan and MRI. Herpes simplex virus (HSV) antibody estimation in CSF and blood was done simultaneously using ELISA. Patients with diagnosis of cerebral venous thrombosis, cerebral malaria, tubercular meningitis etc, who resembled herpes simplex encephalitis (HSE), were excluded systematically with relevant investigations. 28 patients showed electroencephalographic, serologic and/or neuroradiological evidence of herpes simplex encephalitis. Males were affected more than females. Age ranged from 4 years to 65 years. Main clinical features included altered sensorium (100%) and seizures (89%). Serological test for HSV antibody in CSF and blood was positive in 14 patients. Fronto-temporal localisation was seen in EEG of 18 patients. CT and MRI were fairly characteristic with bilateral asymmetric fronto-temporal lesions. Patients with mild disease and who reported earlier responded well to treatment with acyclovir. Mortality was higher if treatment was delayed or if the disease was severe. Delayed treatment even in less severe cases produced neurological deficit in many survivors. Despite limitations of non-availability of CSF-PCR and serial estimation of HSV antibodies, the study is an attempt to highlight the value of high index of suspicion of HSE on clinical grounds, systematically excluding cases with different aetiologies resembling HSE and planning early antiviral therapy to reduce both mortality and morbidity associated with this fatal disease.     

Demonstration of herpes simplex virus DNA in CSF cells by in situ hybridization for early diagnosis of herpes encephalitis

Summary Herpes simplex virus (HSV) was studied by in situ DNA hybridization with a biotinylated cDNA probe in 56 air-dried methanol-fixed cerebrospinal fluid (CSF) cell preparations which had been collected from 12 patients with herpes simplex encephalitis (HSE) during the previous 5 years. In three additional HSE cases, freshly prepared acetone-fixed CSF cell preparations were available. In all cases, CSF cell preparations were obtained by cytocentrifugation. Herpes simplex virus DNA could be demonstrated in 8 of the 12 HSE cases with methanol-fixed cells (66%) and in all 3 cases with fresh acetone-fixed CSF cells. The earliest CSF sample was available at the onset of symptoms and showed positive DNA hybridization. In three cases hybridization was positive after a clinical course of more than 5 weeks but was usually found in the 1st week of illness before the beginning of specific inthrathecal IgG synthesis. In 54 control cases with other acute inflammatory diseases of the CNS, including 14 cases of varicella-zoster meningitis, no positive hybridization was detected. These findings strongly suggest that in situ hybridization in CSF cells is a reliable tool for the early and rapid diagnosis of HSE, especially at the onset of the disease, when no antibodies can be detected.     

Herpes simplex encephalitis relapses in children: differentiation of two neurologic entities

Relapses of herpes simplex encephalitis (HSE) occurring after the completion of antiviral treatment have been reported repeatedly in children. The authors report data on six children who had at least one relapse of HSE. Two different mechanisms may account for these relapses, including viral replication or an immuno-inflammatory process, with different therapeutic attitudes. Relapses with viral replication may reveal host susceptibility to herpes simplex virus infection.     

A polymerase chain reaction assay of cerebrospinal fluid in patients with suspected herpes simplex encephalitis.

A polymerase chain reaction (PCR) was used to detect herpes simplex virus (HSV) deoxyribonucleic acid (DNA) in CSF of 109 patients with possible herpes simplex encephalitis. HSV DNA was found in 20/109 patients. In 14 of these patients the diagnosis was confirmed by a rise in CSF antibodies, isolation of HSV from the brain, or both. In 3 patients CSF antibodies did not rise and 3 patients did not have a follow up lumbar puncture or a brain biopsy. In 19/20 patients HSV DNA was present in the first CSF specimen. The virus was identified as HSV I in 15 patients and HSV II in 4; the virus was not typed in the other patient. A possible diagnosis of herpes simplex encephalitis was not confirmed in the 89 PCR-negative patients. HSV DNA was present in CSF of 3 patients who had meningitis with herpetic genital infections but it was not found in 24 patients with other neurological diseases. The results suggest that the detection of HSV DNA in CSF using a PCR assay will be an accurate method of early diagnosis of herpes simplex encephalitis.     

Primary herpes virus infection and ischemic stroke in childhood: A new association?

We describe, to our knowledge, the first case of arterial ischemic stroke after primary herpes simplex virus type 1 (HSV1) infection in a previously healthy child, without signs of encephalitis. A 10-year-old previously healthy girl was admitted to our hospital with acute left-sided hemiparesis which involved the lower half of her face. Submandibular lymphadenitis and oral vesicular lesions were present. MRI confirmed the suspicion of an acute ischemic stroke. Immunoglobulin M antibodies to HSV1 were detected. Cerebrospinal fluid polymerase chain reaction for herpes virus was negative. She was treated with aspirin (3 mg/kg) and intravenous acyclovir (10 mg/kg every 8 hours) for 21 days. Immunoglobulin G antibodies to HSV1 appeared 16 days after admission. Twelve months after her hospitalization the patient’s examination was normal. Stroke should be considered a possible complication of HSV1 primary infection. Guidelines for the management of acute stroke in children are needed.     

Akathisia in association with herpes simplex encephalitis relapse and opercular syndrome in children

We report a 2-year-old boy with herpes simplex virus type 1 encephalitis (HSE) and opercular syndrome who presented with clinical relapse characterized by chorea-like involuntary movements that suggest akathisia. The patient initially presented with multiple focal seizures that cause epilepsia partialis continua, polymerase chain reaction (PCR) for herpes simplex virus type 1 was positive. He developed hypersalivation, speech and swallowing difficulties within 30 days. Based on these findings the patient was diagnosed as having opercular syndrome due to HSE. He developed akathisia on 44th day of admission as a relapse and he was successfully treated with propranolol.     

Herpes simplex encephalitis: diagnostic problems and late relapse

A 5-year-old female presented with prolonged afebrile right-sided focal seizures, right brachio-facial paralysis, and dysarthria; consciousness was not altered. Fever appeared 20 hours after onset of neurological symptoms. At admission (day 1) cerebral computerized tomography and cerebrospinal fluid (CSF) analyses were normal including undetectable alpha-interferon (alpha-IFN) and negative herpes simplex virus (HSV) polymerase chain reaction (PCR). Acyclovir was started at a dosage of 60mg/kg/day for 21 days and neurological symptoms improved. Cerebral magnetic resonance imaging (MRI) showed lesions in the left thalamus and left parietal lobe. On day 8, CSF contained an elevated leukocyte count with a predominance of lymphocytes, but alpha-IFN and HSV DNA were still undetectable. Delayed intrathecal synthesis of specific anti-HSV antibodies was found on day 26 and confirmed herpes simplex encephalitis (HSE) diagnosis. Twenty months after this episode, the patient presented with a febrile meningeal syndrome. PCR detected HSV DNA in CSF and cerebral imaging showed a new left temporal lesion. At relapse onset, intrathecal synthesis of specific anti-HSV antibodies had disappeared. Acyclovir was started at a dosage of 60mg/kg/day for 21 days and neurological status improved. At discharge, neurological examination showed right hemiparesis and bucco-facial dyspraxia. Diagnostic problems of HSE diagnosis in children are highlighted. It is suggested that the premature disappearance of intrathecal synthesis of a specific anti-HSV antibody might play a permissive role in the resurgence of cerebral viral replication.     

Viral encephalitis

Acute viral encephalitis may be caused by a wide range of viruses but the most important is herpes simplex encephalitis (HSE) because of its severity, especially if untreated, and its good response to specific treatment with acyclovir. The outcome of any CNS viral infection is dependent on both the immune status of the host and the virulence of the infecting virus. In evaluating a patient with suspected viral encephalitis there are 3 essential steps, namely the identification of a true parenchymal virus infection of the brain rather than a non–infective encephalopathy, the distinction of an infectious viral encephalitis from an acute disseminated encephalomyelitis (ADEM), and then the determination, where possible, of the specific virus involved. In practice, the precise viral cause of the encephalitis may never be established. Analysis of the CSF for herpes simplex virus (HSV) DNA using the Polymerase Chain Reaction (PCR) has been a significant advance in the diagnosis of HSE as this test has a very high sensitivity and specificity especially with appropriate sample timing. It is essential to commence early treatment with intravenous acyclovir in patients suspected of having HSE because of the remarkable safety and efficacy of this drug and the dangers of delaying potentially effective treatment of life threatening disease. This review outlines the general management approach in patients suspected of having viral encephalitis.     

Clinico-pathologic case of slowly progressive herpes simplex encephalitis without temporal necrosis

A case of herpes simplex encephalitis (HSE) is reported. The patient experienced short term memory disorders and irritability progressing over 3 months, without seizures or fever. The CSF was normal. CT showed a small low density area in the right posterior orbito-frontal region. At post-mortem examination, one month later, the temporal cortex appeared largely spared by necrosis, which involved the posterior orbito-frontal areas. Cowdry type A inclusions, herpes virus like particles and fluorescent reaction with HSV1 monoclonal antibodies strongly supported the diagnostic. Such atypical cases of long duration have apparently seldom been reported. They suggest that HSE should be considered in the differential diagnosis of a subacute encephalopathy.