Herpes simplex virus type 1 DNA in cerebrospinal fluid of a patient with Mollaret's meningitis

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.

Epstein-Barr virus--associated acute autonomic neuropathy

A 44-year-old man developed blurry vision, photosensitivity, orthostasis, constipation, and acrodysesthesias after a febrile illness. The neurologic examination and ancillary studies were consistent with a dysautonomic small fiber neuropathy. The cerebrospinal fluid (CSF) contained both Epstein-Barr virus (EBV) DNA and antibody to EBV. This is the first report of an acute autonomic neuropathy with documented EBV infection in CSF.

Recurring episodes of meningitis (Mollaret's meningitis) with one showing an association with herpes simplex virus type 2

Benign recurrent aseptic (Mollaret's) meningitis is a rare disease of unknown aetiology. We report the case of a 27-year-old woman who experienced three episodes of lymphocytic meningitis. Human Simplex Virus (HSV) type 2 DNA was detected in the CSF by PCR amplification indicating the diagnosis of recurrent HSV type 2 meningitis. Our observation suggests that search of herpes virus DNA by PCR amplification on CSF may be useful in unexplained recurrent meningitis.

Differential in situ hybridization for herpes simplex virus typing in routine skin biopsies

A herpes simplex virus (HSV) type 2 specific recombinant plasmid probe designated pH2S3 was constructed from non-HSV-1 crossreactive regions of the HSV-2 genome. DNA in situ hybridization on in vitro reconstructed tissue samples of sheep collagen matrix impregnated with herpes virus-infected human cells was used to demonstrate absence of crossreactivity of the pH2S3 probe with HSV-1 and varicella zoster virus under stringent posthybridization washing conditions. It was demonstrated that DNA in situ hybridization with pH2S3 allows specific detection of HSV-2 in routine formalin-fixed, paraffin-embedded patient material.

Herpes simplex virus genomes in human nervous system tissue analyzed by polymerase chain reaction

Herpes simplex virus (HSV) is known to establish latency in human trigeminal ganglia. It has been speculated that the virus might also be present in latent fashion in normal human brain, where it might be responsible for conditions such as herpes simplex encephalitis, and less plausibly as a cause for multiple sclerosis or Alzheimer's disease. To test the possibility that HSV exists in normal human brain, we utilized the polymerase chain reaction to assess the frequency and distribution of HSV genomes in the nervous system tissues of patients dying of nonneurological causes. Nine samples were obtained in a systematic fashion from olfactory bulb, gyrus rectus, hippocampus amygdala, calcarine cortex, pons, medulla, cerebellum, and trigeminal ganglia from each of 40 individuals dying of nonneurological disease. HSV genomes were sought in each sample using primers from four regions of the HSV genome. The primers were capable of detecting HSV genomic sequences from as little as 10 fg of DNA. HSV genomic sequences were identified in 26 (65%) of 40 samples of trigeminal ganglia. From 30 patients seropositive to HSV, sequences were amplified from 23 (77%). HSV genomic sequences could be amplified and detected in 14 (35%) of 40 brains. The positive areas included medulla, olfactory bulbs, pons, gyrus rectus, amygdala, and hippocampus. The study has confirmed the previous demonstration of latent HSV in trigeminal ganglia in normal humans. The frequency of latent HSV in trigeminal ganglia is in general agreement with results obtained by explanation of ganglia.(ABSTRACT TRUNCATED AT 250 WORDS)

Acute myocarditis. Rapid diagnosis by PCR in children

BACKGROUND

The diagnosis of viral myocarditis remains difficult and generally depends on clinical and histological criteria. Viral cultures and serology are often unrewarding, with low yields. The purpose of this study was to analyze the usefulness of polymerase chain reaction (PCR) in the rapid diagnosis of acute myocarditis in children.

METHODS AND RESULTS

PCR was used to analyze 38 myocardial tissue samples from 34 patients with suspected acute viral myocarditis and 17 control patients with congenital heart disease (14) or hypertrophic cardiomyopathy (3). Myocardial samples were obtained at the time of right ventricular biopsy (13 samples), from explanted hearts (18 samples) at transplantation, and from cardiac autopsy specimens (24 samples) and were evaluated for the presence of enterovirus, cytomegalovirus (CMV), adenovirus, and herpes simplex virus (HSV) using PCR primers designed to consensus and unique sequences of these viral genomes. Blood also was obtained at the time of biopsy (11) or transplant (18). In 26 of 38 myocardial samples (68%), viral genome was detected by PCR (15 adenoviral, 8 enteroviral, 2 HSV, 1 CMV), whereas all control myocardial samples and blood samples were negative. Four patients had positive viral cultures, and these matched the PCR findings. Disagreement with histopathology occurred in 13 of 26 PCR-positive specimens, usually associated with adenovirus.

CONCLUSIONS

PCR offers a rapid, sensitive diagnostic method for myocardial viral infection. While enterovirus is an important etiological agent, adenovirus was more prevalent in this series and should be evaluated when etiology is sought. PCR used in conjunction with standard endomyocardial biopsy appears to enhance the likelihood of detecting viral genome in the myocardium of patients with clinical evidence of myocarditis.

Acyclovir-resistant neonatal herpes simplex virus infection of the larynx

A 10-day-old infant with stridor was found to have herpes simplex virus type 2 infection of the larynx. The infant's poor clinical response to both acyclovir and foscarnet prompted extensive clinical and virologic evaluations, which revealed acyclovir-resistant herpes simplex virus.

Zoster sine herpete, a clinical variant

Two otherwise healthy immunocompetent men, ages 62 and 66 years, experienced years of radicular pain without zoster rash. An extensive search for systemic disease and malignancy was negative. Varicella-zoster virus DNA, but not herpes simplex virus DNA, was found in the cerebrospinal fluid of the first patient 5 months after the onset of pain, and in the second patient 8 months after the onset of pain. Prolonged radicular pain without zoster rash combined with the presence of varicella-zoster virus in the cerebrospinal fluid indicates that both men had zoster sine herpete, and strongly supports this syndrome as a clinical variant.

Herpes simplex type 2 in a patient with Mollaret's meningitis: demonstration by polymerase chain reaction

We describe a patient with recurrent self-limited aseptic meningitis meeting the criteria for Mollaret's syndrome, in whom extensive serological investigation and cerebrospinal fluid analysis failed to reveal a specific cause. Using polymerase chain reaction techniques to amplify herpes simplex viral DNA, we were able to identify the presence of herpes simplex virus type 2 in the cerebrospinal fluid. The duration of clinical illness may have been shortened by treatment with intravenous acyclovir. We suggest that herpes simplex virus may be a more common cause of aseptic meningitis than has been demonstrated by current commonly available serological and culture techniques.

Human herpesvirus 6 is present in lesions of Langerhans cell histiocytosis

Langerhans cell histiocytosis (LCH) is a disease characterized by Langerhans cell infiltration of skin and bone, with its most severe form manifested by multifocal infiltration of many organs. The etiology is unknown, although viral infection has been proposed as a potential pathogenic factor. Human herpesvirus 6 (HHV-6), a recently described member of the human herpesvirus family, has been associated with atypical or malignant lymphocytic processes, and immune disorders. Based on these observations, we suspected that HHV-6 may play a role in the pathogenesis of LCH. Lesional tissue of 30 patients with LCH was retrospectively examined for the presence of HHV-6 by using the polymerase chain reaction. Tissue specimens from 63 patients with other benign and malignant histiocytic and lymphocytic diseases served as controls. In addition, all specimens were examined with control primers specific for herpes simplex virus (HSV). HHV-6 DNA was detected in lesions of 14 of 30 patients with LCH (47%). On clinical subgroup analysis, HHV-6 DNA was found in 10 of 16 patients with extraosseous disease (63%) and in four of 14 patients with disease limited to bone (29%). In each case, the prevalence of HHV-6 in LCH lesions was statistically significant, when compared to the control population. HSV DNA was not found in any of the LCH or control specimens. Although the presence of a virus alone does not establish a causal role in the disease, it supports the possibility of an etiologic relationship. From this study, we emphasize the need for further investigation of the potential HHV-6-mediated pathogenesis of LCH.

Molecular biology of herpes simplex virus type 1 latency in the nervous system

Herpes simplex virus (HSV) is one of the best studied examples of viral ability to remain latent in the human nervous system and to cause recurrent disease by reactivation. Intensive effort was directed in recent years to unveil the molecular viral mechanisms and the virus-host interactions associated with latent HSV infection. The discovery of the state of the latent viral DNA in nervous tissues and of the presence of latency-associated gene expression during latent infection, both differing from the situation during viral replication, provided important clues relevant to the pathogenesis of latent HSV infection. This review summarizes the current state of knowledge on the site of latent infection, the molecular phenomena of latency, and the mechanisms of the various stages of latency: acute infection, establishment and maintenance of latency, and reactivation. This information paved the way to recent trials aiming to use herpes viruses as vectors to deliver genes into the nervous system, an issue that is also addressed in this review.

Laboratory techniques in the diagnosis of herpes simplex infection

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Detection of herpes simplex virus DNA in cerebrospinal fluid of Saudi pediatric patients with encephalitis by the polymerase chain reaction

Twelve samples of cerebrospinal fluid (CSF) from Saudi pediatric patients with suspected encephalitis were found negative for herpes simplex virus by cell culture and by nucleic acid hybridization using(32)P-labeled specific probes. After amplification of DNA extracted from 100 microl of each sample using primers for the glycoprotein D gene of HSV, seven specimens were found positive for HSV DNA. Subsequent hybridization with the labeled DNA probe ensured the positivity of the seven samples and further detected one more positive sample, for a total of eight HSV DNA positive cases. This technique improved the detection of HSV in CSF samples and may assist in an early diagnosis for HSV ecephalitis.

Impact of herpesvirus infections in the future

Numerous diverse, often opposing, trends will determine the frequency (and severity) of herpesvirus infections in the future. A major factor is the growing population of iatrogenically immunocompromised patients, accruing especially from large increases in organ and autologous bone marrow transplantation. Of even greater importance is the immense number of human immunodeficiency virus (HIV)-infected patients for whom herpesviruses may: (1) have been a cofactor in acquisition of HIV infection; (2) contribute to in vivo activation of HIV; (3) cause severe infections. Another factor influencing severe herpesvirus infections is the aging of populations in developed countries; this will be associated with a greater prevalence, and more morbid manifestations, of herpes zoster. Sociologic changes will also be important. The consequences of these, such as attempts to influence sexual practices, will be difficult to predict. Other changes, such as more frequent use of early child care facilities, will predictably lead to early acquisition of most herpesviruses, thereby decreasing the incidence of severe disease in adulthood. Factors that will reduce the incidence and/or severity of herpesvirus infections include vaccines (varicella, herpes simplex, cytomegalovirus); prophylactic strategies for immunocompromised hosts (passive immunization, antiviral drugs, blood product selection); more rapid and sensitive diagnostic methods; and suppressive or early antiviral therapy for common infections, such as genital herpes simplex and varicella.(ABSTRACT TRUNCATED AT 250 WORDS)

A prospective study of the polymerase chain reaction for detection of herpes simplex virus in cerebrospinal fluid submitted to the clinical virology laboratory

Polymerase chain reaction (PCR) was prospectively performed with cerebrospinal fluid (CSF) from 51 patients whose CSF was available for analysis and was submitted for viral culture and/or herpes simplex virus (HSV) serology and 20 patients whose CSF was submitted exclusively to the Clinical Biochemistry Laboratory. Primers were used that flanked a 92 bp segment of the HSV DNA polymerase gene (35 cycles). Amplified products were electrophoresed on agarose gel, blotted onto nylon membrane, and probed with a 32P-labelled sequence internal to the primers. For nested PCR, 1 microliter of PCR product was amplified for an additional 35 cycles before electrophoresis and Southern blot analysis. Review of the clinical records revealed that 15 patients had central nervous system (CNS) infections. Specific HSV DNA sequences were detected in CSF specimens of three of the individuals [PCR(2), nested PCR(1)]. Two of these patients had disseminated HSV infection including encephalitis and one patient had aseptic meningitis. The diagnoses of the 12 patients with CNS infection who did not have HSV DNA detected in CSF included encephalitis [varicella-zoster virus (1), cytomegalovirus (1), Mycoplasma pneumoniae (1)], meningitis [Neisseria meningitidis (1), Coccidioides immitis (1), Enterovirus (1), aseptic meningitis (1)], varicella-zoster radiculitis (2), human immunodeficiency virus dementia (2), and transverse myelitis due to Epstein-Barr virus (1). Importantly, HSV DNA was also not detected in the CSF of the 36 patients who did not have CNS infection and 20 samples submitted exclusively to the Clinical Biochemistry Laboratory. Our findings demonstrate the utility of PCR as a rapid, non-invasive method for the routine laboratory diagnosis of CNS infection due to HSV.