Herpes simplex virus type 2 infections of the central nervous system: A retrospective study of 49 patients

Characteristics and long-term prognosis of Danish residents with a positive intrathecal antibody index test for herpes simplex virus or varicella-zoster virus compared with individuals with a positive cerebrospinal fluid PCR: a nationwide cohort study

OBJECTIVES

We compared characteristics and outcomes of individuals who in the cerebrospinal fluid (CSF) were positive for herpes simplex virus (HSV) or varicella-zoster virus (VZV)-intrathecal antibody index test ([AI]-positive) vs. individuals who were PCR-positive for HSV type 1 (HSV1), type 2 (HSV2), and for VZV.

METHODS

Nationwide cohort study of all Danish residents with positive CSF-AI or -PCR for HSV or VZV (1995-2021). We calculated short- and long-term risks as age-, sex-, and comorbidity-adjusted odds ratios (aOR), adjusted hazard ratios (aHR), and absolute risk differences with 95% CIs.

RESULTS

Compared with individuals with positive PCR for HSV1 (n = 321), HSV2 (n = 497), and VZV (n = 1054), individuals with a positive AI for HSV (n = 177) and VZV (n = 219) had CSF pleocytosis less frequently (leucocyte count >10/μL: HSV-AI: 39%, VZV-AI: 52%, HSV1-PCR: 81%, HSV2-PCR: 92%, VZV-PCR: 83%), and were less frequently diagnosed with central nervous system infection ([aOR {95%CI}]: HSV-AI vs. HSV1-PCR: [0.1 {0.1, 0.2}], HSV-AI vs. HSV2-PCR: [0.1 {0.0, 0.1}], VZV-AI vs. VZV-PCR: [0.2 {0.2, 0.3}]). Individuals with a positive HSV-AI or VZV-AI had increased risk of demyelinating disease ([aOR {95%CI}; aHR {95%CI}]: HSV-AI vs. HSV1-PCR: [4.6 {0.9, 24.5}; aHR not applicable], HSV-AI vs. HSV2-PCR: [10.4 {2.3, 45.9}; 12.4 {2.3, 66.0}], VZV-AI vs. VZV-PCR: [aOR not applicable; 10.3 {1.8, 58.8}]). Disability pension was less frequent among HSV-AI than HSV1-PCR cohort members (5-year risk difference: -23.6%, 95%CI: -35.2, -11.8), and more frequent among VZV-AI than VZV-PCR cohort members (5-year risk difference: 16.8%, 95%CI: 5.0, 28.7).

DISCUSSION

AI-positive individuals differ from PCR-positive individuals in several aspects. AI appears unspecific for current central nervous system infections.

Clinical features and prognostic factors in adults with viral meningitis

Clinical features applicable to the entire spectrum of viral meningitis are limited, and prognostic factors for adverse outcomes are undetermined. This nationwide population-based prospective cohort study included all adults with presumed and microbiologically confirmed viral meningitis in Denmark from 2015 until 2020. Prognostic factors for an unfavourable outcome (Glasgow Outcome Scale score of 1-4) 30 days after discharge were examined by modified Poisson regression. In total, 1066 episodes of viral meningitis were included, yielding a mean annual incidence of 4.7 episodes per 100 000 persons. Pathogens were enteroviruses in 419/1066 (39%), herpes simplex virus type 2 in 171/1066 (16%), varicella-zoster virus in 162/1066 (15%), miscellaneous viruses in 31/1066 (3%) and remained unidentified in 283/1066 (27%). The median age was 33 years (IQR 27-44), and 576/1066 (54%) were females. In herpes simplex virus type 2 meningitis, 131/171 (77%) were females. Immunosuppression [32/162 (20%)] and shingles [90/149 (60%)] were frequent in varicella-zoster virus meningitis. The triad of headache, neck stiffness and hyperacusis or photophobia was present in 264/960 (28%). The median time until lumbar puncture was 3.0 h (IQR 1.3-7.1), and the median CSF leucocyte count was 160 cells/µl (IQR 60-358). The outcome was unfavourable in 216/1055 (20%) 30 days after discharge. Using unidentified pathogen as the reference, the adjusted relative risk of an unfavourable outcome was 1.34 (95% CI 0.95-1.88) for enteroviruses, 1.55 (95% CI 1.00-2.41) for herpes simplex virus type 2, 1.51 (95% CI 0.98-2.33) for varicella-zoster virus and 1.37 (95% CI 0.61-3.05) for miscellaneous viruses. The adjusted relative risk of an unfavourable outcome was 1.34 (95% CI 1.03-1.75) for females. Timing of acyclovir or valacyclovir was not associated with the outcome in meningitis caused by herpes simplex virus type 2 or varicella-zoster virus. In summary, the outcome of viral meningitis was similar among patients with different aetiologies, including those with presumed viral meningitis but without an identified pathogen. Females had an increased risk of an unfavourable outcome. Early antiviral treatment was not associated with an improved outcome in meningitis caused by herpes simplex virus type 2 or varicella-zoster virus.

Fatal HSV-2 primary infection most likely acquired by kidney transplantation: A case report

Herpes simplex virus 2 (HSV-2) rarely causes severe disease, even in solid organ transplant recipients. This paper describes a fatal case of HSV-2 infection, probably transmitted from a donor to a kidney transplant recipient. The donor was seropositive for HSV-2 but not for HSV-1, whereas the recipient was seronegative for both viruses before transplantation, suggesting that the graft was the source of infection. The recipient received valganciclovir prophylaxis due to cytomegalovirus seropositivity. Three months after transplantation, the recipient presented with rapidly disseminated cutaneous HSV-2 infection with meningoencephalitis. The HSV-2 strain was resistant to acyclovir, probably acquired under valganciclovir prophylaxis. Despite early initiation of acyclovir therapy, the patient died. This fatal case of HSV-2 infection, probably transmitted by the kidney graft with acyclovir-resistant HSV-2 from the onset, is uncommon.

Treatment of Herpes Simplex Virus Type 2 Meningitis: A Survey Among Infectious Diseases Specialists in France, Sweden, Australia, and Denmark

Background

We aimed to describe attitudes toward treatment of herpes simplex virus type 2 (HSV-2) meningitis and prioritize future trials.

Methods

This was a self-administered online survey of HSV-2 meningitis treatment among infectious diseases (ID) specialists in France, Sweden, Australia, and Denmark.

Results

A total of 223 ID specialists (45% female) from France (36%), Denmark (24%), Sweden (21%), and Australia (19%) participated in the survey, primarily from university hospitals (64%). The estimated overall response rate was 11% and ranged from 6% (Australia) to 64% (Denmark). Intravenous (IV) acyclovir followed by oral valacyclovir was the favored treatment in 110 of 179 (61%), whereas monotherapy with either IV acyclovir or oral valacyclovir was used by 35 of 179 (20%) and 34 of 179 (19%), respectively. The median total duration was reported to be 7 days (interquartile range, 7-10 days) regardless of antiviral regimen. Immunocompromise influenced decisions on antiviral treatment in 110 of 189 (58%) of respondents, mainly by prolonged total duration of treatment (36/110 [33%]), prolonged IV administration (31/110 [28%]), and mandatory antiviral treatment (25/110 [23%]). Treatment with acyclovir/valacyclovir versus placebo and comparison of acyclovir versus valacyclovir were assigned the highest prioritization scores for future randomized controlled trials on HSV-2 meningitis.

Conclusions

Perceptions of indications for as well as type and duration of antiviral treatment varied substantially among ID specialists.

Application of metagenomic next-generation sequencing technique for diagnosing a specific case of necrotizing meningoencephalitis caused by human herpesvirus 2

Reactivation of latent human herpesvirus 2 (HHV-2) can cause spontaneous recovering aseptic meningitis and recurrent meningitis in adults, but it rarely affects the brain parenchyma to cause encephalitis. Here, we report the case of a 37-year-old male patient admitted to our hospital due to fever with a progressive headache for 3 days and paroxysmal episodes of unconsciousness for 1 day. Brain magnetic resonance imaging (MRI) revealed viral meningoencephalitis. Then, metagenomics next-generation sequencing (mNGS) was applied, which detected 12,024 unique sequences of HHV-2 in cerebrospinal fluid (2022), indicating HHV-2 encephalitis. After antiviral treatment, the patient’s symptoms improved, and he was discharged. During the 1-month follow-up, the patient recovered without any new symptoms, but a brain MRI revealed significant atrophy of the original foci. The patient was finally diagnosed with HHV-2 necrotizing meningoencephalitis, which is extremely rare. mNGS helped with the clinical diagnosis and strengthened our understanding of HHV-2 infections in the central nervous system.

Primary HSV-2 Infection Complicated by Radiculomyelitis in a Young Immunocompetent Female Patient with Inherited Chromosomally Integrated HHV-6: A Case Report

Background: HSV-1, HSV-2 and VZV are alpha Herpesviruses, neurotropic viruses that are associated with various neurologic complications upon primary infection or reactivation. Cases of myelitis and radiculomyelitis are rare and appropriate etiologic diagnoses can be tricky. Case presentation: Here we describe the case of a young immunocompetent woman who developed painful and extended vesicular genital lesions, with subsequent radiculomyelitis. HSV-1/-2 PCRs in the cerebrospinal fluid were misleadingly negative, whereas HHV-6 PCR was positive. Positive anti-HSV-2 IgM and IgG in serum was consistent with HSV-2 primary infection. On the other hand, the detection of HHV-6 DNA was explained by inherited chromosomally integrated HHV-6. The clinical course was favorable with high-dose IV acyclovir and corticosteroids. Conclusion: HSV-2-related radiculomyelitis is a rare clinical entity, which can be difficult to diagnose. In this case report, the causative virus was not detected in the patient’s CSF, whereas HHV-6 DNA, non-pathogenic in this situation, was paradoxically positive. The diagnosis was based on the clinical features typical for HSV-2 primary infection, confirmed by the serology results. The delay between the genital lesions and the appearance of the radiculomyelitis, along with the absence of HSV-2 detection in the CSF, suggests a possible immuno-mediated physiopathological process. As for the HHV-6 DNA detection in the patient’s CSF, it was explained by inherited chromosomally integrated HHV-6. This case illustrates how both negative and positive clinical virology results need careful interpretation according to the clinical findings.

Herpes simplex virus 2 meningitis in adults: A prospective, nationwide, population-based cohort study

BACKGROUND

Data on the clinical presentation are scarce and prognostic factors of Herpes simplex virus type 2 (HSV-2) meningitis remain unknown.

METHODS

Prospective, nationwide, population-based database identifying all adults treated for HSV-2 meningitis at departments of infectious diseases in Denmark from 2015-2020. Unfavorable outcome was defined as Glasgow Outcome Scale (GOS) score of 1-4 and extended GOS score of 1-6. Modified Poisson regression was used to compute relative risks with 95% confidence intervals (RR, 95% CI) for unfavorable outcome.

RESULTS

HSV-2 meningitis was diagnosed in 205 cases (76% female, median age 35 [IQR 27-49]) yielding an incidence of 0.7/100,000/year. Common symptoms were headache 195/204 (95%), photo/phonophobia 143/188 (76%), and neck stiffness 106/196 (54%). Median time to lumbar puncture was 2.0 hours (IQR 1-4.8) and cerebrospinal fluid (CSF) leukocyte count was 360x10 6/L (IQR 166-670) with a mononuclear predominance of 97% (IQR 91-99). Lumbar puncture was preceded by brain imaging in 61/205 (30%). Acyclovir/valaciclovir was administered in 197/205 (96%) cases for a median of 10 days (IQR 7-14).Unfavorable outcome was observed in 64/205 (31%) at discharge and 19/181 (11%) after six months and was not associated with female sex (RR 1.08, 95% CI 0.65-1.79), age ≥35 years (1.28, 0.83-1.97), immuno-compromise (1.07, 0.57-2.03), or CSF leukocyte count >1,000x10 6/L (0.78, 0.33-1.84).

CONCLUSIONS

HSV-2 meningitis often presented as meningeal symptoms in younger females. Unfavorable outcome at discharge was common and was not associated with sex, age, immune-compromise, or CSF leukocyte count. Sequelae persisted beyond six months in one tenth of patients.

Long-Term Survival, Morbidity, Social Functioning and Risk of Disability in Patients with a Herpes Simplex Virus Type 1 or Type 2 Central Nervous System Infection, Denmark, 2000-2016

Background

The long-term prognosis following herpes simplex virus (HSV) central nervous system (CNS) infection is still debated.

Patients and Methods

We examined outcomes in all Danish residents who, during 2000–2016, tested PCR positive for HSV-1 (n=208) or HSV-2 (n=283) in the cerebrospinal fluid, compared to comparison cohorts from the general population (n=2080 and n=2830).

Results

One-year mortality was increased among HSV-1 patients (difference 19.3%; 95% CI: 13.6% to 25.0%) and HSV-2 patients (difference 5.3%; 95% CI: 2.5% to 8.1%), but thereafter mortality was not increased. After exclusion of persons diagnosed with cancer prior to study inclusion, one-year mortality difference for HSV-2 patients was 1.7% (−0.1% to 3.5%). After five years, HSV-1 patients had lower employment (difference −19.8%; 95% CI: −34.7% to −4.8%) and higher disability pension rates (difference 22.2%; 95% CI: 8.4% to 36.0%) than the comparison cohort, but similar number of inpatient days, outpatient visits, and sick leave. HSV-2 patients had employment and disability pension rates comparable to the comparison cohort, but more inpatient days (difference 1.5/year; 95% CI: −0.2 to 3.2), outpatient visits (difference 1.3/year; 95% CI: 0.3 to 3.2), and sick leave days (difference 9.1/year; 95% CI: 7.9 to 10.4).

Conclusion

HSV-1 and HSV-2 CNS infections differ substantially with respect to prognosis. HSV-1 CNS infection is followed by increased short-term mortality and long-term risk of disability. HSV-2 CNS infection has no substantial impact on mortality or working capability but is associated with increased morbidity.

Viral meningitis: current issues in diagnosis and treatment

PURPOSE OF REVIEW

The purpose of this review is to give an overview of viral meningitis and then focus in on some of the areas of uncertainty in diagnostics, treatment and outcome.

RECENT FINDINGS

Bacterial meningitis has been declining in incidence over recent years. Over a similar time period molecular diagnostics have increasingly been used. Because of both of these developments viral meningitis is becoming relatively more important. However, there are still many unanswered questions. Despite improvements in diagnostics many laboratories do not use molecular methods and even when they are used many cases still remain without a proven viral aetiology identified. There are also no established treatments for viral meningitis and the one potential treatment, aciclovir, which is effective in vitro for herpes simplex virus, has never been subjected to a clinical trial.

SUMMARY

Viruses are in increasingly important cause of meningitis in the era of declining bacterial disease. The exact viral aetiology varies according to age and country. Molecular diagnostics can not only improve the rate of pathogen detection but also reduce unnecessary antibiotics use and length of hospitalization. Further research is required into treatments for viral meningitis and the impact in terms of longer term sequelae.

Cost-Effectiveness Study of Criteria for Screening Cerebrospinal Fluid To Determine the Need for Herpes Simplex Virus PCR Testing

The absence of markers of inflammation in the cerebrospinal fluid (CSF) commonly predicts the absence of herpes simplex virus (HSV) central nervous system (CNS) infection. Consequently, multiple authors have proposed and validated criteria for deferring HSV PCR testing of CSF in immunocompetent hosts with normal CSF white blood cell and protein levels (≤5 cells/mm³ and ≤50 mg/dl, respectively). Hosts are considered immunocompetent if they are ≥2 years old and have not had HIV or an organ transplant. Adoption of the criteria may erroneously exclude HSV-infected persons from a necessary diagnostic test or, alternatively, reduce the costs associated with HSV tests with minimal to no effect on patient care. Little is known about the cost-effectiveness of this approach. A decision analysis model was developed to evaluate the adoption of criteria for screening HSV tests of CSF. Estimates of input parameter values combined available literature with a multiyear multisite review at two of the largest health care systems in the United States. Adoption of criteria to screen for HSV test need proved cost-effective when less than 1 in 200 patients deferred from testing truly had an HSV CNS infection. Similar to prior studies, none of the deferred cases had HSV encephalitis (n = 3120). Adoption of these criteria in the United States would save an estimated $127 million ($95 million to $158 million [±25%]) annually. The model calculations remained robust to variation in test cost, prevalence of HSV infection, and random variation to study assumptions. The adoption of criteria to screen HSV PCR tests in CSF represents a cost-effective approach.

Herpes simplex type 2 encephalitis and methotrexate medication: a fortuitous or causative association in a patient with spondyloarthritis?

It is unclear whether immunosuppression is a risk factor for herpes encephalitis. Herein, we describe a rare case of herpes simplex virus type 2 encephalitis in a patient treated with low-dose methotrexate for HLA-B27-associated spondyloarthritis. The patient was successfully treated with acyclovir but presented sequelae of encephalitis. Here we discuss the possible role of low-dose methotrexate therapy as a risk factor of neurological herpes reactivation and severe disease. The host-related and viral risk factors are also addressed.

Herpes simplex and varicella zoster CNS infections: clinical presentations, treatments and outcomes

OBJECTIVES

To describe the clinical manifestations, cerebrospinal fluid (CSF) characteristics, imaging studies and prognostic factors of adverse clinical outcomes (ACO) among adults with herpes simplex virus (HSV) or varicella zoster virus (VZV) CNS infections.

METHODS

Retrospective review of adult patients with positive HSV or VZV polymerase chain reaction on CSF from an observational study of meningitis or encephalitis in Houston, TX (2004-2014), and New Orleans, LA (1999-2008).

RESULTS

Ninety-eight adults patients were identified; 25 had encephalitis [20 (20.4 %) HSV, 5 (5.1 %) VZV], and 73 had meningitis [60 (61.1 %) HSV and 13 (13.3 %) VZV]. HSV and VZV had similar presentations except for nausea (P < 0.01) and rash (P < 0.001). The CSF profile did not differ between HSV and VZV infection. Abnormal neuroimaging findings were found in 11.6 % (10/86) brain CTs and 21.3 % (16/75) brain MRIs. The EEG was abnormal in 57.9 % (11/19). Sixteen patients (16.3 %) had an ACO (10 HSV encephalitis, 3 VZV encephalitis and 3 VZV meningitis). Intravenous acyclovir administered within 48 h was protective against an ACO [OR 0.19 (0.04-0.80), P = 0.02). However, on logistic regression only Charlson comorbidity score >1 and an encephalitis presentation were independently associated with an ACO. The treatment for HSV meningitis was variable, and all patients had a good clinical outcome.

CONCLUSION

Alpha herpes CNS infections due to HSV and VZV infections have similar clinical and laboratory manifestations. ACO was observed more frequently in those patients with comorbidities and an encephalitis presentation.

HSV-2 meningoencephalitis in an immunocompetent young man: what is the pathogenesis and what is the treatment?

Herpes simplex encephalitis is rarely caused by herpes simplex virus type 2 (HSV-2) after the neonatal period. The pathogenesis of HSV-2 encephalitis is not known and its treatment has not been discussed. We report a case of mild meningoencephalitis secondary to HSV-2 primary infection after sexual risk behaviour in a healthy young man. The diagnosis was established upon clinical, biological and electroencephalographic criteria. Aciclovir treatment led to rapid clinical improvement. This case highlights HSV-2 as a rare cause of meningoencephalitis, and questions the management of this rare manifestation of HSV-2 infection.

Long-term neuropsychiatric consequences of aseptic meningitis in adult patients

Aseptic meningitis is considered a benign and self-limiting clinical condition. In contrast to viral encephalitis and bacterial meningitis, the prognosis is usually good. The existing literature is scarce on the potential long-term neuropsychiatric consequences of aseptic meningitis. Previous studies have primarily been retrospective and differences in methodologies make it difficult to draw conclusions regarding the prevalence and nature of neuropsychiatric manifestations. However, studies have reported decreased psychomotor speed and impaired executive and visuo-constructive functions following aseptic meningitis. Larger controlled prospective studies are urgently needed to elucidate the neuropsychiatric complications of aseptic meningitis.

Comparison of clinical manifestations, outcomes and cerebrospinal fluid findings between herpes simplex type 1 and type 2 central nervous system infections in adults

In previous reports on the viral causes of central nervous system (CNS) infections, it has been generally recognized that HSV-1 is a major cause of encephalitis, while HSV-2 is the predominant cause of aseptic meningitis in adults. To examine this matter, the clinical characteristics in the two types of HSV CNS infections were investigated. In a retrospective cohort study which included all adult patients (≥16 years) between January 1999 and December 2013 in a 2,700-bed tertiary care hospital, all the patients in whom PCR of the CSF for HSV was positive were identified. Ninety-five patients with positive CSF PCR results for HSV were included, 21 with HSV-1 and 74 with HSV-2. Many patients with HSV-1 had encephalitis (13/21, 61.9%), whereas most patients with HSV-2 had meningitis (62/74, 83.8%). However, HSV-1 and HSV-2 accounted for similar proportion of patients with HSV encephalitis (13/25, 52.0% vs. 12/25, 48.0%). Neurological sequelae were more frequent among patients with HSV-1 (9/21, 42.9% vs. 6/74, 8.1%; P = 0.001). The present study suggests that HSV-2 is not only a major cause of aseptic meningitis, but also it may cause serious manifestation as HSV-1 encephalitis in adults.

Herpes simplex virus type 2-associated recurrent aseptic (Mollaret's) meningitis in genitourinary medicine clinic: a case report

INTRODUCTION

Cases of idiopathic recurrent benign aseptic meningitis were first described by Mollaret. Today, herpes simplex virus (HSV) is considered the cause of most cases of Mollaret's meningitis.

CASE REPORT

A 40-year-old male was referred to our genitourinary medicine clinic with recurrent genital herpetic lesions. He had HSV-2-positive genital ulcers 8 years earlier. One year after the first infection, he developed severe recurrent attacks of headache associated with meningitis symptoms. The results of all radiological and biochemical tests were normal, but the patient reported a correlation between his attacks and genital herpes flare-ups. We diagnosed the patient with Mollaret's meningitis and started him on continuous suppressive acyclovir therapy, which resulted in marked clinical improvement.

DISCUSSION

Mollaret's meningitis is a rare form of idiopathic recurrent aseptic meningitis that has a sudden onset, short duration, and spontaneous remission with unpredictable recurrence. We believe that the presence of concurrent or recurrent mucocutaneous herpetic lesions can aid its diagnosis, prior to which, affected patients usually have many unnecessary investigations and treatments. Therefore, detailed sexual history should be sought in all patients with aseptic meningitis, and clinicians should also ask about history of recurrent headaches in all patients with recurrent herpetic anogenital lesions. Continuous suppressive acyclovir therapy may reduce the frequency and severity of attacks and can dramatically improve lifestyle.

Herpes simplex virus 2 meningitis: a retrospective cohort study

Herpes simplex virus 2 is a leading cause of viral meningitis and the most commonly recognized infectious cause of benign, recurrent meningitis. We report a retrospective, observational cohort study of patients with herpes simplex virus type 2 (HSV-2) meningitis, confirmed by polymerase chain reaction (PCR) in the cerebrospinal fluid (CSF). The terms "herpes simplex," "meningitis," or "encephalitis" were searched in the medical records system of the Mayo Clinic in Rochester, Minnesota (1995-2008). Patients were included if they had a clinical diagnosis of meningitis and HSV-2 detected by PCR in the CSF. There were 28 patients with 33 episodes identified (83 % female; mean age at presentation of meningitis 36 years, range 17-53; mean time to HSV2 detection from symptom onset 3 days, range 0-6; history of genital herpes 23 %). No patient took oral antiviral treatment at the time of presentation. Episodes were most likely to include headache (100 %), photophobia (47 %), self-reported fever (45 %), meningismus (44 %), and nausea and/or vomiting (29 %). CSF at the time of meningitis was notable for elevated protein (mean 156 g/dL, range 60-258) and white cell count (mean 504 cells/μL, range 86-1,860) with normal glucose (mean 54 mg/dL, range 32-80). Mollaret cells were never detected. Neuroimaging was most often normal (83 %) when performed, although some cases showed nonspecific (14 %) or meningeal changes (3 %). There was no consistent relationship to genital herpes. The duration of treatment with intravenous acyclovir ranged from 3 to 14 days for the first meningitic episode (daily dose range from 500 to 1,000 mg and total dose range from 500 mg q8h for 3 days to 800 mg q8h for 14 days). For subsequent episodes, the duration of treatment of intravenous acyclovir ranged from less than 1 to 14 days (total dose range from 1,390 mg for 1 day to 900 mg q8h for 10 days). The dose of valacyclovir ranged from 500 mg once daily to 500 mg four times daily. The median duration of valacyclovir treatment following the first episode was 10 days (range 3 to 14 days, n = 13). The median duration of valacyclovir treatment following a subsequent meningitic episode was 9 days (range 7 days to indefinite period, n = 9). No patient was reported to have seizures, neurological disability, or death in extended follow-up (mean follow-up 3.4 years). Recurrence of meningitic symptoms was not universal.

Detection of herpes simplex virus (1 and 2), varicella-zoster virus, cytomegalovirus, human herpesvirus 6 and enterovirus in immunocompetent Tunisian patients with acute neuromeningeal disorder

Enteroviruses (EVs) and human herpesviruses (HHVs) are involved frequently in acute neurological disorders of viral etiology. This study aimed to investigate the incidence of herpes simplex virus types-1 (HSV-1) and 2 (HSV-2), varicella-zoster virus (VZV), cytomegalovirus (CMV), human herpesvirus 6 (HHV-6) and human enteroviruses (EVs) in cerebrospinal fluid (CSF) samples of Tunisian immunocompetent patients with neuromeningeal disorders. The patients had been hospitalized at the Fattouma Bourguiba University Hospital (Monastir, Tunisia) between September 2007 and June 2009. At least one viral genome was detected in 58 (46%) out of 126 CSF samples collected. Enterovirus was detected in 31 of the positive samples (53.4%), CMV in 20 (34.5%), HSV-1 in 3 (5.2%), HSV-2 in 6 (10.3%), VZV in 4 (6.9%), HHV-6 in 2 (3.4%). More than one viral genome was detected in seven CSF samples, including CMV DNA in six of the samples. The high frequency of enteroviral infections in aseptic meningitis was confirmed. The detection of CMV DNA only suggests a direct role of this virus in the etiology of acute neuromeningeal disorder.

Sex differences in murine susceptibility to systemic viral infections

Increased susceptibility to autoimmunity in females is often viewed as the consequence of enhanced immunoreactivity providing superior protection against infections. We paradoxically observed greater mortality in female compared to male mice during systemic viral infections with three large double-stranded DNA viruses (herpes simplex virus type I [HSV], murine cytomegalovirus [MCMV], and vaccinia virus [VV]). Indeed, female mice were 27-fold more susceptible to infection with HSV than male mice. Elimination of estrogen by ovariectomy in female mice or addition of estrogen to castrated male mice only partially eliminated the observed sex differences following HSV infection. However, the differences observed in survival between female and male mice were nearly abrogated in the absence of type I interferon receptor signaling and substantially mitigated in absence of DAP12 signaling. Interestingly, the sex-specific impact of type I interferon receptor and DAP12 signaling differentially influenced survival during systemic viral infections with type I interferon receptor signaling enhancing male survival and DAP12 signaling increasing the susceptibility of female mice. These results have potential implications for the sex disparities observed in human autoimmune disorders.

Herpes simplex encephalitis during treatment with tumor necrosis factor-alpha inhibitors

We report 3 cases of herpes simplex virus encephalitis in patients receiving tumor necrosis factor-alpha (TNF-alpha) inhibitors for rheumatologic disorders. Although TNF-alpha inhibitors have been reported to increase the risk of other infectious diseases, to our knowledge, an association between anti-TNF-alpha drugs and herpes simplex virus encephalitis has not been previously described.

Herpes simplex type-2 meningitis: presentation and lack of standardized therapy

BACKGROUND

Herpes simplex type-2 (HSV-2) causes both primary and recurrent lymphocytic meningitis, but optimal patient management is not well defined.

METHODS

In this retrospective observational study, we reviewed the medical records of patients with HSV-2-positive cerebrospinal fluid samples in our laboratory between January 2001 and January 2005.

RESULTS

During the study period, 23 patients, aged 16 to 83 years, had HSV-2 detected in spinal fluid. Nineteen (83%) had meningitis and 4 (17%) had evidence of meningoencephalitis. Seventy-four percent were female. Two (8.7%) had a history of prior genital herpes, and one (4.3%) had genital lesions noted at the time of presentation. Genital examinations were performed at presentation in only 3 patients. Seven (30.4%) patients reported previous episodes of meningitis. Two celibate women developed HSV-2 meningitis or meningoencephalitis following lumbar steroid injection for spinal stenosis. One woman developed HSV-2 meningoencephalitis 3 days postpartum following cesarean section. Antiviral treatment for uncomplicated HSV-2 meningitis varied from none (4 patients) to 14-21 days of intravenous (IV) acyclovir therapy (4 patients). The 11 remaining patients with meningitis received 1-7 days of IV therapy, followed by 7-21 days of oral antiviral therapy. Three of 4 patients with meningoencephalitis received 21 days of IV acyclovir, and one received 3 days IV acyclovir followed by 14 days of oral therapy.

CONCLUSIONS

HSV-2 meningitis presents most often without a history of genital herpes, recurrent meningitis, or genital symptoms. Current management practices are highly variable and may lead to unnecessary hospitalization and prolonged intravenous therapy.

A case of maternal herpes simplex virus encephalitis during late pregnancy

BACKGROUND

A pregnant 25-year-old woman at 32 weeks' gestation was admitted to an emergency unit after her husband had found her drowsy and with her tongue bitten. The day before admission, the patient had developed a fever of 39 degrees C, was suffering from headaches, was nauseated and had vomited. On admission, she had anterograde and retrograde amnesia, but no somatic neurological deficits were detected.

INVESTIGATIONS

Routine laboratory testing, lumbar puncture, cerebrospinal fluid analysis, routine bacteriology, brain MRI, and polymerase chain reaction testing for neurotropic viruses including herpes simplex virus types 1 and 2.

DIAGNOSIS

Maternal herpes simplex virus type 1 encephalitis.

MANAGEMENT

Antiviral and anticonvulsive therapy, supportive treatment, and cesarean section.