Search

Introduction: Herpes simplex encephalitis (HSE) is the most frequent cause of sporadic necrotizing encephalitis in adults. The aim of this study is to describe the characteristics of HSE and the factors influencing its outcome., Material and Methods: Retrospective study of patients diagnosed with HSE in a tertiary care teaching hospital over a 15-year period. Diagnosis was based on a consistent clinical profile for HSE, plus either a PCR-positive CSF HSV study or consistent brain neuroimaging findings. Patients were divided into 2 groups according to the modified Rankin Scale: good outcome (Grades <=2) and poor outcome (Grades >=3)., Results: Thirty-five patients were included. Mean age was 53.9 years. More than half presented febricula or fever, headache, disorientation, behavioral changes, decreased level of consciousness, or neurological deficit. CSF glucose concentration was normal in all patients and WBC count was normal in 8 (23%). PCR for HSV was positive in 92% and cranial MRI was suggestive of HSE in 100% of patients. Mortality was 8.6%. In relation to outcome, age (OR=1.079; 95% CI, 1.023-1.138) and serum albumin level at admission (OR=0.87; 95% CI, 0.794-0.954) were independent prognostic factors at discharge. At 6 months, days of fever after initiation of acyclovir therapy (OR=1.219; 95% CI, 1.046-1.422) and serum albumin level at admission (OR=0.917; 95% CI, 0.87-0.967) were independent prognostic factors., Conclusions: Normal brain MRI or detection of low CSF glucose concentration requires consideration of diagnoses other than HSE. Age, serum albumin level at admission, and days of fever after initiation of acyclovir therapy were independent prognostic factors of the disease.

Objective: To assess the performance of a polymerase chain reaction (PCR) method in cerebrospinal fluid (CSF) for the diagnosis of nervous system infections caused by herpesvirus, and to estimate the incidence of encephalitis due to herpes simplex virus type 1 in the adult population of the island of Gran Canaria., Methods: We studied 330 CSF specimens from 312 patients (281 HIV-negative and 31 HIV-positive) remitted to investigate clinically suspected encephalitis or meningitis, or to study neuropathy or demyelinating disease. A multiplex PCR technique was used to detect herpes simplex virus types 1 and 2 (HSV-1 and HSV-2), varicella-zoster virus (VZV), human cytomegalovirus (CMV), Epstein-Barr virus and human herpesvirus type 6. The patients' clinical records were reviewed to establish the definite diagnosis., Results: Nine samples from eight patients (2.6%) showed positive results (9.7% of patients with pathological CSF and none with normal CSF). The eight patients had clinical and analytic findings of herpesvirus nervous system infection: HSV-1 DNA in four patients with encephalitis, HSV-2 DNA in one patient with meningitis, VZV DNA in two patients with meningitis and CMV DNA in one HIV-positive patient with encephalitis. Herpesvirus was the cause of 50% of encephalitis cases and 10% of meningitis cases. The incidence of HSV-1 encephalitis was five cases per million inhabitants per year., Conclusions: Diagnosis of herpesvirus nervous system infections by PCR in CSF is not appropriate when CSF parameters are normal. We found a higher incidence of herpesvirus encephalitis than has been reported in other studies.

Objective: To evaluate the usefulness of a rapid and simple PCR method in the diagnosis of herpetic meningoencephalitis in a pediatric population., Patients and Methods: One hundred twenty-three cerebrospinal fluid samples from 114 pediatric patients attending the Hospital Sant Joan de Déu in Barcelona for clinical suspicion of viral meningoencephalitis or to rule out a possible herpetic etiology were evaluated. In addition to classical methods, the diagnostic technique used was PCR amplification of a highly preserved region of the DNA polymerase gene common to herpes virus 1 and 2. All patients were administered acyclovir on admission and until the results of PCR were known. If the result was negative, withdrawal of acyclovir was considered after clinical reexamination. If the result was positive, the therapy was continued for 20 days., Results: Herpes simplex DNA was detected in four patients. In all patients, clinical outcome confirmed the results of PCR, whether positive or negative. PCR results were available within 6.30 and 72 hours (mean: 18 hours)., Conclusion: This simple and rapid PCR technique can be applied in the daily routine of the microbiology laboratory. It allows early diagnosis of herpetic meningocephalitis or, when lacking, exclusion of Herpes simplex etiology.