Neurologic morbidity after herpes simplex virus type 2 meningitis: a retrospective study of 40 patients

Viral lumbosacral radiculitis (Elsberg syndrome) in Denmark

PURPOSE

To describe clinical features and outcomes of viral lumbosacral radiculitis (Elsberg syndrome).

METHODS

Nationwide population-based cohort study of all adults hospitalised for viral lumbosacral radiculitis at departments of infectious diseases in Denmark from 2015 to 2020.

RESULTS

Twenty-eight patients with viral lumbosacral radiculitis were included (mean annual incidence: 1.2/1,000,000 adults). The median age was 35 years (IQR 27-43), and 22/28 (79%) were female. All patients had urinary retention, with 17/28 (61%) needing a catheter. On admission, at least one sign or symptom of meningitis (headache, neck stiffness, photophobia/hyperacusis) was present in 18/22 (82%). Concurrent genital herpetic lesions were present in 11/24 (46%). The median cerebrospinal fluid leukocyte count was 153 cells/µL (IQR 31-514). Magnetic resonance imaging showed radiculitis/myelitis in 5/19 (26%). The microbiological diagnosis was herpes simplex virus type 2 in 19/28 (68%), varicella-zoster virus in 2/28 (7%), and unidentified in 7/28 (25%). Aciclovir/valaciclovir was administered in 27/28 (96%). At 30 days after discharge, 3/27 (11%) had persistent urinary retention with need of catheter. At 180 days after discharge, moderate disabilities (Glasgow Outcome Scale score of 4) were observed in 5/25 (20%).

CONCLUSIONS

Urinary retention resolved within weeks in most patients with viral lumbosacral radiculitis, but moderate disabilities according to the Glasgow Outcome Scale were common at the end of follow-up.

Benign recurrent lymphocytic meningitis (Mollaret's meningitis) in Denmark: a nationwide cohort study

BACKGROUND AND PURPOSE

Data on clinical features and outcomes of benign recurrent lymphocytic meningitis (BRLM) are limited.

METHODS

This was a nationwide population-based cohort study of all adults hospitalized for BRLM associated with herpes simplex virus type 2 (HSV-2) at the departments of infectious diseases in Denmark from 2015 to 2020. Patients with single-episode HSV-2 meningitis were included for comparison.

RESULTS

Forty-seven patients with BRLM (mean annual incidence 1.2/1,000,000 adults) and 118 with single-episode HSV-2 meningitis were included. The progression risk from HSV-2 meningitis to BRLM was 22% (95% confidence interval [CI] 15%-30%). The proportion of patients with the triad of headache, neck stiffness and photophobia/hyperacusis was similar between BRLM and single-episode HSV-2 meningitis (16/43 [37%] vs. 46/103 [45%]; p = 0.41), whilst the median cerebrospinal fluid leukocyte count was lower in BRLM (221 cells vs. 398 cells; p = 0.02). Unfavourable functional outcomes (Glasgow Outcome Scale score of 1-4) were less frequent in BRLM at all post-discharge follow-up visits. During the study period, 10 (21%) patients with BRLM were hospitalized for an additional recurrence (annual rate 6%, 95% CI 3%-12%). The hazard ratio for an additional recurrence was 3.93 (95% CI 1.02-15.3) for patients with three or more previous episodes of meningitis.

CONCLUSIONS

Clinical features of BRLM were similar to those of single-episode HSV-2 meningitis, whilst post-discharge outcomes were more favourable. Patients with three or more previous episodes of meningitis had higher risk of an additional recurrence.

An IKBKE variant conferring functional cGAS/STING pathway deficiency and susceptibility to recurrent HSV-2 meningitis

The mechanisms underlying susceptibility to recurrent herpes simplex virus type 2 (HSV-2) meningitis remain incompletely understood. In a patient experiencing multiple episodes of HSV-2 meningitis, we identified a monoallelic variant in the IKBKE gene, which encodes the IKKε kinase involved in induction of antiviral IFN genes. Patient cells displayed impaired induction of IFN-β1 (IFNB1) expression upon infection with HSV-2 or stimulation with double-stranded DNA (dsDNA) and failed to induce phosphorylation of STING, an activation marker of the DNA-sensing cyclic GMP-AMP synthase/stimulator of IFN genes (cGAS/STING) pathway. The patient allele encoded a truncated IKKε protein with loss of kinase activity and also capable of exerting dominant-negative activity. In stem cell-derived microglia, HSV-2-induced expression of IFNB1 was dependent on cGAS, TANK binding kinase 1 (TBK1), and IKBKE, but not TLR3, and supernatants from HSV-2-treated microglia exerted IKBKE-dependent type I IFN-mediated antiviral activity upon neurons. Reintroducing wild-type IKBKE into patient cells rescued IFNB1 induction following treatment with HSV-2 or dsDNA and restored antiviral activity. Collectively, we identify IKKε to be important for protection against HSV-2 meningitis and suggest a nonredundant role for the cGAS/STING pathway in human antiviral immunity.

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.

Herpes Simplex Virus 1 and 2 Infections during Differentiation of Human Cortical Neurons

Herpes simplex virus 1 (HSV-1) and 2 (HSV-2) can infect the central nervous system (CNS) with dire consequences; in children and adults, HSV-1 may cause focal encephalitis, while HSV-2 causes meningitis. In neonates, both viruses can cause severe, disseminated CNS infections with high mortality rates. Here, we differentiated human induced pluripotent stem cells (iPSCs) towards cortical neurons for infection with clinical CNS strains of HSV-1 or HSV-2. Progenies from both viruses were produced at equal quantities in iPSCs, neuroprogenitors and cortical neurons. HSV-1 and HSV-2 decreased viability of neuroprogenitors by 36.0% and 57.6% (p < 0.0001), respectively, 48 h post-infection, while cortical neurons were resilient to infection by both viruses. However, in these functional neurons, both HSV-1 and HSV-2 decreased gene expression of two markers of synaptic activity, CAMK2B and ARC, and affected synaptic activity negatively in multielectrode array experiments. However, unaltered secretion levels of the neurodegeneration markers tau and NfL suggested intact axonal integrity. Viral replication of both viruses was found after six days, coinciding with 6-fold and 22-fold increase in gene expression of cellular RNA polymerase II by HSV-1 and HSV-2, respectively. Our results suggest a resilience of human cortical neurons relative to the replication of HSV-1 and HSV-2.

Clinical use of steroids in viral central nervous system (CNS) infections: three challenging cases

The role of adjunctive corticosteroids in reducing morbidity and mortality of viral CNS infections remains poorly defined. Clinicians are often left in a quagmire regarding steroid use in complex and rapidly evolving viral CNS infections. Limited studies have explored the underlying mechanisms behind the potential benefit of steroids. Here, we describe steroid use in three cases of viral CNS disease: varicella zoster virus (VZV), Powassan virus, and influenza A-associated acute necrotizing encephalopathy.

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.

Herpes Simplex Virus Type 2 Radiculomyelitis Disguised as Conversion Disorder

Herpes simplex virus type 2 (HSV-2) is the most common cause of genital herpes with a seroprevalence of 20-30% in developed countries and 80% worldwide. In addition to neonatal encephalitis and meningitis, HSV-2 is associated with radiculomyelitis marked by pain, paresis, sphincter disturbances, sensory loss, or ascending necrotizing myelitis. We report the case of a patient with a lengthy psychiatric history who presented with lower extremity pain and weakness. Cervical, thoracic, and lumbar MRI scans with and without gadolinium contrast revealed no significant stenosis, neural compression, or other abnormal findings, and the brain MRI with and without gadolinium contrast was normal. The initial diagnosis was conversion disorder due to myriad psychological stressors. Polymerase chain reaction (PCR) of CSF detected HSV-2 and a lymphocytic pleocytosis, and the diagnosis of radiculomyelitis was confirmed. She was treated with i.v. acyclovir for 3 weeks followed by valacyclovir. The patient attained no improvement of her symptoms within 8 months; however, she reported decreased pain and improved strength of the lower extremities by 17 months. Neurologists should be aware of the association between HSV-2 and radiculomyelitis, particularly in the setting of a patient with psychiatric comorbidities. Recognition of HSV-2 through PCR of CSF and prompt treatment with acyclovir may prevent devastating neurological sequelae.

Combined testing for herpes simplex virus and Mycobacterium tuberculosis DNA in cerebrospinal fluid of patients with aseptic meningitis in Burkina Faso, West Africa

BACKGROUND

Little is known about the involvement of herpes simplex virus (HSV) or Mycobacterium tuberculosis (MTB) as potentially curable causes of central nervous system (CNS) infections in sub-Saharan Africa.

OBJECTIVE

In this study, we developed a PCR assay dedicated to simultaneous testing of HSV1/HSV2 and MTB in Burkina Faso, a country where HSV is neglected as a cause of CNS infection and where TB prevalence is high.

METHODS

A consensus HSV1/HSV2 set of primers and probe were designed and combined to primers and probe targeting the IS6110 repetitive insertion sequence of MTB. Analytical performances of the assay were evaluated on reference materials. Cerebrospinal fluid (CSF) collected from subjects with aseptic meningitis was tested for HSV1/HSV2 and MTB DNA.

RESULTS

The UL29 gene was chosen as a highly conserved region targeted by the HSV1/HSV2 nucleic acid test. The lower limits of detection were estimated to be 2.45 copies/µL for HSV1, 1.72 copies/µL for HSV2, and 2.54 IS6110 copies per µL for MTB. The PCR was used in 202 CSF collected from subjects suspected of aseptic meningitis. Five samples (2.46%) tested positive, including two children positive for HSV1 (0.99%) and three adults tested positive for MTB (1.47%).

CONCLUSION

Using an in-house real-time PCR assay, we showed that both HSV and MTB are etiologic pathogens contributing to aseptic meningitis in Burkina Faso. This molecular test may have clinical utility for early diagnosis for those treatable CNS infections.

CXCL11 production in cerebrospinal fluid distinguishes herpes simplex meningitis from herpes simplex encephalitis

Background

The closely related herpes simplex viruses 1 and 2 can cause inflammations of the central nervous system (CNS), where type 1 most often manifest as encephalitis (HSE), and type 2 as meningitis (HSM). HSE is associated with severe neurological complications, while HSM is benign in adults. We proposed that studying the chemokine and cytokine production in cerebrospinal fluid (CSF) and serum could indicate why two closely related viruses exhibit different severity of their accompanied CNS inflammation.

Methods

Secretion patterns of 30 chemokines and 10 cytokines in CSF of adult patients with acute HSE (n = 14) and HSM (n = 20) in the initial stage of disease were analyzed and compared to control subjects without viral central nervous system infections and to levels in serum.

Results

Most measured chemokines and cytokines increased in CSF of HSE and HSM patients. Overall, the CSF chemokine levels were higher in CSF of HSM patients compared to HSE patients. However, only five chemokines reached levels in the CSF that exceeded those in serum facilitating a positive CSF-serum chemokine gradient. Of these, CXCL8, CXCL9, and CXCL10 were present at high levels both in HSE and HSM whereas CXCL11 and CCL8 were present in HSM alone. Several chemokines were also elevated in serum of HSE patients but only one in HSM patients. No chemokine in- or efflux between CSF and serum was indicated as the levels of chemokines in CSF and serum did not correlate.

Conclusions

We show that HSM is associated with a stronger and more diverse inflammatory response in the CNS compared to HSE in the initial stage of disease. The chemokine patterns were distinguished by the exclusive local CNS production of CXCL11 and CCL8 in HSM. Inflammation in HSM appears to be restricted to the CNS whereas HSE also was associated with systemic inflammation.

Electronic supplementary material

The online version of this article (doi:10.1186/s12974-017-0907-5) contains supplementary material, which is available to authorized users.

Elsberg syndrome: A rarely recognized cause of cauda equina syndrome and lower thoracic myelitis

Objective:

Elsberg syndrome (ES) is an established but often unrecognized cause of acute lumbosacral radiculitis with myelitis related to recent herpes virus infection. We defined ES, determined its frequency in patients with cauda equina syndrome (CES) with myelitis, and evaluated its clinical, radiologic, and microbiologic features and outcomes.

Methods:

We searched the Mayo Clinic medical records for ES and subsequently for combinations of index terms to identify patients with suspected CES and myelitis.

Results:

Our search yielded 30 patients, 2 diagnosed with ES and an additional 28 with clinical or radiologic evidence of CES retrospectively suspected of having ES. We classified patients in 5 groups according to diagnostic certainty. MRI and EMG confirmed that 2 had only myelitis, 5 only radiculitis, and 16 both. Two had preceding sacral herpes infection and 1 oral herpes simplex. Spinal cord lesions were commonly multiple, discontinuous, not expansile, and centrally or ventrally positioned. Lesions generally spared the distal conus. Nerve root enhancement was occasionally prominent and was smooth rather than nodular. Lymphocytic CSF pleocytosis was common. Thirteen patients (43%) had viral isolation studies, which were commonly delayed; the delay may have accounted for the low rate of viral detection. Acyclovir was administered to 6 patients. Most patients recovered with sequelae; 1 patient experienced encephalomyelitis and died.

Conclusion:

ES is a definable condition likely responsible for 10% of patients with combined CES and myelitis. Radiologic findings are not entirely specific but may help in differentiating ES from some competing diagnostic considerations. We propose criteria to facilitate diagnosis.

Detection of Herpes Simplex and Varicella-Zoster Viruses in Patients with Bell's Palsy by the Polymerase Chain Reaction Technique

Objectives:

Infectious causes of peripheral facial paralysis are well known. Bell's palsy, however, is an idiopathic facial paralysis, and the genesis is still unknown. Herpes simplex virus type 1 (HSV-1) and varicella-zoster virus (VZV) have been suggested as etiologic agents.

Methods:

Twenty consecutive adult patients with Bell's palsy were included in the study. Ten adult patients operated on for chronic otitis served as controls. A biopsy specimen from the posterior auricular muscle was resected within 72 hours after the onset of Bell's palsy and was analyzed together with cerebrospinal fluid (CSF) by nested polymerase chain reaction for HSV-1 and VZV DNA. Serum samples were analyzed for antibodies to HSV-1 and VZV.

Results:

HSV-1 DNA was found in the muscle biopsy specimen from 1 of the 20 patients, but was not found in any of the CSF samples. VZV DNA was detected in the muscle biopsy as well as the CSF from 1 other patient. All controls were negative. Seventeen of 19 patients had stationary serum antibody concentrations to HSV-1, and none displayed an antibody titer rise. A significant antibody titer rise to VZV was found in 1 of 19 patients, whereas 17 of 19 had stationary antibody levels.

Conclusions:

HSV-1 or VZV DNA was detected in 10% of patients with Bell's palsy in the present study. Viral replication might already have declined in many cases at the onset of the palsy. Use of an HSV-1/VZV polymerase chain reaction on a muscle biopsy specimen or CSF does not seem to be the method of choice for rapid etiologic diagnosis in the acute phase of Bell's palsy.

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.

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.

Peripheral nervous system manifestations of infectious diseases

Infectious causes of peripheral nervous system (PNS) disease are underrecognized but potentially treatable. Heightened awareness educed by advanced understanding of the presentations and management of these infections can aid diagnosis and facilitate treatment. In this review, we discuss the clinical manifestations, diagnosis, and treatment of common bacterial, viral, and parasitic infections that affect the PNS. We additionally detail PNS side effects of some frequently used antimicrobial agents.

Hemorrhagic and ischemic stroke secondary to herpes simplex virus type 2 meningitis and vasculopathy

Herpes simplex virus type 2 (HSV-2) meningitis dogmatically is benign and self-limited in the immune competent patient. However, we describe how left untreated HSV-2 meningitis can be complicated by vasculitis and both ischemic and hemorrhagic stroke. We report a 57-year-old woman with lymphocytic meningitis complicated by ischemic stroke and intracerebral hemorrhage in the setting of vasculopathy and HSV-2 DNA detected in CSF successfully treated with acyclovir and corticosteroids. Subsequent angiographic magnetic resonance imaging revealed improvement in the vasculopathy after treatment. This case demonstrates that HSV-2 meningitis may take a less benign course and further provides the first evidence of angiographic improvement in addition to clinical improvement after definitive treatment.

Herpes simplex virus meningitis complicated by ascending paralysis

A case of herpes simplex virus (HSV) meningitis complicated by ascending paralysis with almost complete recovery following antiviral treatment is reported. We present this case to illustrate the importance of including HSV-induced neuropathy in the differential diagnosis of acute neurologic symptoms following the viral illness.

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.

Long-term valacyclovir suppressive treatment after herpes simplex virus type 2 meningitis: a double-blind, randomized controlled trial

BACKGROUND

Herpes simplex virus type 2 (HSV-2) is a common cause of acute and recurrent aseptic meningitis. Our aim was to determine the impact of antiviral suppression on recurrence of meningitis and to delineate the full spectrum of neurological complications.

METHODS

One hundred and one patients with acute primary or recurrent HSV-2 meningitis were assigned to placebo (n = 51) or 0.5 g of valacyclovir twice daily (n = 50) for 1 year after initial treatment with 1 g of valacyclovir 3 times daily for 1 week in a prospective, placebo-controlled, multicenter trial. The primary outcome was time until recurrence of meningitis. The patients were followed up for 2 years.

RESULTS

The first year, no significant difference was found between the valacyclovir and placebo groups. The second year, without study drugs, the risk of recurrence of verified and probable HSV-2 meningitis was significantly higher among patients exposed to valacyclovir (hazard ratio, 3.29 [95% confidence interval, 10.06-10.21]). One-third of the patients experienced 1-4 meningitis episodes during the study period. A considerable morbidity rate, comprising symptoms from the central, peripheral, and autonomous nervous system, was found in both groups.

CONCLUSIONS

Suppressive treatment with 0.5 g of valacyclovir twice daily was not shown to prohibit recurrent meningitis and cannot be recommended for this purpose after HSV meningitis in general. Protection against mucocutaneous lesions was observed, but the dosage was probably inappropriate for the prevention of HSV activation in the central nervous system. The higher frequency of meningitis, after cessation of active drug, could be interpreted as a rebound phenomenon.

Mollaret's meningitis and herpes simplex virus type 2 infections

Benign recurrent aseptic meningitis is a rare disorder described by Mollaret in 1944. When initially described, this form of aseptic meningitis had no identifiable infecting agent. New sophisticated diagnostic tools have now identified herpes simplex type 2 virus as the most commonly isolated agent. Antiviral treatment has been used successfully for prophylaxis and treatment.

Low prevalence of varicella zoster virus and herpes simplex virus type 2 in saliva from human immunodeficiency virus-infected persons in the era of highly active antiretroviral therapy

OBJECTIVES

Human herpesviruses, e.g., herpes simplex virus (HSV) type 1, Epstein-Barr virus, and cytomegalovirus, appear in saliva at greater frequency in persons infected with human immunodeficiency virus (HIV) than in healthy individuals. However, it is not known if varicella zoster virus (VZV) and HSV-2 appear simultaneously during HIV infection at greater frequency in saliva in this era of highly active antiretroviral therapy (HAART). The aim of this study was to investigate the prevalence and amounts of VZV and HSV-2 in the saliva of HIV-infected orally asymptomatic patients.

STUDY DESIGN

Quantitative polymerase chain reaction was used to investigate the prevalence, quantity, risk, and correlations of salivary VZV and HSV-2 from 59 HIV-seropositive individuals and 53 healthy control subjects in a case-control cross-sectional study. Seventy-eight percent of the HIV-seropositive patients (46 out of 59) were taking HAART.

RESULTS

VZV DNA was detected in the saliva of 5.1% (3 out of 59) of the HIV-positive group and in only 1 healthy control 1.9% (1 out of 53; P = .62). The amount of VZV DNA in the expressors was low, generally <1,100 copies/mL, with no observed difference between the HIV-positive group and the control subjects (P = 1.0). HSV-2 DNA was not detected in either group. In the HIV-infected group, VZV shedding occurred in those on HAART, but was not associated with oral lesions, specific CD4(+) or CD8(+) T-cell levels, or demographic factors.

CONCLUSIONS

Varicella zoster virus was detected at low prevalence in the saliva of HIV-infected persons, whereas HSV-2 was not detected in the saliva of this cohort. HAART does not appear to diminish the risk for asymptomatic VZV shedding.

Recurrent lymphocytic meningitis positive for herpes simplex virus type 2

We found the prevalence of recurrent lymphocytic meningitis associated with herpes simplex virus type 2 (HSV-2) was 2.2/100,000 population in Finland during 1996-2006, higher than previous estimates. PCR was most sensitive in detecting HSV-2 DNA from cerebrospinal fluid if the sample was taken 2-5 days after symptom onset.

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.

Aseptic meningitis and encephalitis because of herpesviruses and enteroviruses in an immunocompetent adult population

BACKGROUND AND AIM

Human herpesviruses (HHVs) and enteroviruses (EVs) are the major causative agents of CNS viral infections. The aim of the study was to identify the etiology and determine the frequency of aseptic meningitis and encephalitis due to HHVs and EVs in an immunocompetent adult population.

METHODS

Eighty-one patients (ages >or=15) with aseptic meningitis or encephalitis treated in the Infectious Diseases Hospital of Thessaloniki, Greece, during 2003-2006, were included in the study. Polymerase chain reaction for detection of herpes- and enterovirus genome direct in cerebrospinal fluid samples was performed.

RESULTS

Based on clinical and laboratory data, 36/81 patients had meningitis and 45/81 had encephalitis. Etiology was defined in 11 patients (31%) with aseptic meningitis. EVs were the major causative agents (8/36, 22%), followed by varicella zoster virus (2/36, 5%) and herpes simplex virus-2 (HSV-2) (1/36, 3%). Etiology was identified in 8 of 45 (18%) patients with encephalitis, EV (4/45, 9%) and HSV-1 (4/45, 9%) being the most common pathogens.

CONCLUSION

Enteroviruses are the most common cause of adult aseptic meningitis and together with HSV-1 the main causes of encephalitis.

Central nervous system infections of herpesvirus family

Herpesviruses are one of the most common groups of pathogens causing central nervous system infections in humans. They mostly cause encephalitis, meningitis, or myelitis in immunocompetent and immunocompromised patients. Children, adults, and the elderly can all be affected. Although contrast-enhanced CT is more widely used for diagnosis, contrast-enhanced MR imaging combined with diffusion-weighted imaging is superior to CT in the detection of early changes and the real extent of the disease, and in assessing prognosis and monitoring response to antiviral treatment. More sophisticated techniques, such as MR spectroscopy and perfusion imaging, can aid in the differential diagnosis of herpesvirus infections from other tumoral, demyelinating, and ischemic processes.

[Herpes simplex virus meningitis in 11 patients]

METHOD

We reviewed retrospectively the demographic, clinical, biological characteristics and outcomes of 11 patients with HSV meningitis.

RESULTS

Among the 11 patients, six were infected with HIV, four had a documented history of genital herpes, and one recurrent meningitis. In all cases, the onset of symptoms was abrupt, with severe headache and fever. On admission, 9/11 patients had severe meningismus; two patients had HSV anogenital ulcerations. CSF analysis showed in every case a significant increased of leukocytes with a lymphocytic pleocytosis, a mild elevated protein level and a normal glucose level. HSV was detected in the CSF in every case by PCR: the typing performed on six patients was positive in every case for HSV-2. Intravenous acyclovir (IV ACV) was started in 10/11 cases (range: 3-10 days), switched to valaciclovir (VACV) (range: 5-7 days); one patient was treated with ACV per os for 10 days. The total resolution of symptoms occurred within 48hours in every case. Two patients presented with recurrent HSV-2 meningitis in the next two months, with favorable outcome under IV ACV: a switch to long term VACV 500mg/day was prescribed without any recurrence. No patient presented with recurrence after a median follow-up of 30 months.

CONCLUSION

Early recognition and treatment might improve the outcome of such infections. Adjunctive oral VACV after IV ACV treatment seems to be associated with a good clinical response in patients presenting with HSV meningitis. The duration of such treatments, including prophylactic treatments to prevent recurrent episodes must be better documented.

Herpes simplex encephalitis in Sweden, 1990-2001: incidence, morbidity, and mortality

BACKGROUND

Herpes simplex encephalitis (HSE) is a devastating disease.

METHODS

In Sweden, a nationwide retrospective study of the incidence, morbidity, and mortality associated with HSE during the 12-year period 1990-2001 was conducted. The national inpatient register data were used, and diagnostic data from the virus laboratories were validated.

RESULTS

In the study period, 638 patients hospitalized in Sweden received a primary diagnosis of HSE. Of these, 236 patients had a confirmed infection of the central nervous system due to herpes simplex virus type 1. This corresponds to an incidence of confirmed HSE due to herpes simplex virus type 1 of 2.2 cases per million population per year. Of the survivors, 87% were readmitted to the hospital. The most frequent diagnosis at readmission was epilepsy, which was found in 49 patients (21% of the 236 total patients; 24% of 203 survivors), with a median onset 9.3 months after the diagnosis of HSE. This corresponds to a 60- to 90-fold increase in risk, compared with that for the general population. Neuropsychiatric sequelae were evident in 45 (22%) of 203 surviving patients. The incidence of venous thromboembolism, including pulmonary embolism, was 5-14 times higher than that in the general population. Among patients with HSE due to herpes simplex virus type 1, the 1-year mortality was 14% (33 of 236 patients died), which was 8 times higher than expected.

CONCLUSIONS

This is, to our knowledge, the first study to report long-term, nationwide follow-up data for patients with virologically confirmed HSE. There is considerable morbidity after HSE, with epilepsy being the most common diagnosis. This demonstrates the need for expanding our knowledge of the pathogenesis of HSE to direct more effective antiviral and antiinflammatory treatments.

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

Herpes simplex virus type 2 (HSV-2) infections of the central nervous system (CNS) are rare with meningitis as the most common clinical presentation. We have investigated the clinical spectrum of CNS infections in 49 adult consecutive patients with HSV-2 genome in the cerebrospinal fluid (CSF). HSV-2 in the CSF was determined by polymerase chain reaction (PCR), and patients were diagnosed as encephalitis or meningitis according to predefined clinical criteria by retrospective data information from consecutive clinical journals. The annual crude incidence rate of HSV-2 CNS disease was 0.26 per 100,000. 43 (88%) had meningitis of whom 8 (19%) had recurring lymphocytic meningitis. Six patients (12%) had encephalitis. 11 of 49 patients (22%) had sequelae recorded during follow-up. None died as a result of HSV-2 CNS disease. Thus, the clinical presentation of HSV-2 infection of the CNS is mainly meningitis but encephalitis does occur and neurological sequelae are common. Recurring lymphocytic meningitis is associated with reactivation of HSV-2 and the condition might be underdiagnosed.

Increased detection rate in diagnosis of herpes simplex virus type 2 meningitis by real-time PCR using cerebrospinal fluid samples

Efficient and sensitive diagnostic methods are needed in the management of virus infections in the central nervous system. There is a demand for an evaluation of the sensitivity of PCR methods for early diagnosis of meningitis due to herpes simplex type 2 (HSV-2) and varicella-zoster virus (VZV). The objective of this study was to evaluate real-time PCR in the detection of HSV-2 and VZV DNA from cerebrospinal fluid (CSF) for etiological diagnoses in clinically well-characterized cases of primary and recurrent aseptic meningitis. Samples from 110 patients, 65 of whom were diagnosed with or were strongly suspected of having HSV-2 meningitis and 45 with acute aseptic meningitis of unknown causes, were analyzed. Results were compared with the outcome of nested PCR for HSV-2 infection. Clinical parameters were analyzed in relation to CSF viral load. With real-time PCR, HSV-2 DNA was found in CSF from 80% (52/65) of patients with clinical HSV-2 meningitis compared to 72% (47/65) found by nested PCR. The sensitivity of real-time HSV-2 PCR was found to be 87% (33/38) in primary and 70% (19/27) in recurrent meningitis. The HSV-2 viral load was significantly higher in primary than in recurrent meningitis and correlated with the degree of inflammation. VZV DNA was detected in 2 of 45 samples (4.4%). Real-time PCR for the diagnosis of HSV-2 meningitis was evaluated in a large, clinically well-characterized sample of material and found to identify more cases than nested PCR in the group of patients with recurrent meningitis. Quantification of DNA enables further research of disease prognosis and treatment.

Main adult herpes virus infections of the CNS

Herpes viruses are widely involved in human infectious diseases, and some are life threatening, such as CNS infections. These manifestations vary according to the type of virus involved and the immune status of the patient. This article will review the clinical manifestations (encephalitis, myelitis, meningitis and postinfectious encephalomyelitis), the diagnostic strategies and the presently used drugs (acyclovir, valacyclovir, ganciclovir, valgancyclovir, foscarnet and cidofovir). The review will also discuss drugs that are currently in the pipeline and that could be used in the future.

Multiphasic encephalomyelitis in a patient with recurrent herpes simplex type 2 meningitis

We here describe a patient with a history of recurrent HSV-2 meningitis who had been free from symptoms for almost 20 y when he developed an acute encephalomyelitis. The clinical course laboratory and radiological findings support an acute multiphasic disseminated encephalomyelitis induced by a recurrent HSV-2 infection.

Herpes simplex virus type 2 recurrent meningitis (Mollaret's meningitis): a consideration for the recurrent pathogenesis

We report a 44-year-old Japanese woman with herpes simplex virus (HSV) type 2 recurrent meningitis (Mollaret's meningitis). The diagnosis was confirmed by nested polymerase chain reaction in her cerebrospinal fluid, but the patient's conventional HSV antibodies by complement fixation, neutralizing test or enzyme immunoassay showed low titres with low lymphoproliferative response. Several similar cases are discussed. Although the reason for the recurrent pathogenesis is uncertain, our report suggests that the low immune response including immune evasion may be involved in the pathogenesis of HSV type 2 recurrent meningitis. For this patient, long-term suppressive and patient-initiated therapies were conducted to prevent the recurrence of meningitis.