Discrimination between viral and nonviral meningitis by visually analyzed and quantitative electroencephalography

A prospective study was conducted to assess the ability of the visually analyzed electroencephalogram (VEEG), the quantitative EEG (QEEG) and the Glasgow Coma Scale (GCS) to discriminate between patients with viral and nonviral meningitis. The 55 subjects, aged 14-75 years, fell into one of the following categories: viral (n = 12), bacterial (n = 19), tuberculous (n = 16) or cryptococcal (n = 8) meningitis. EEG recordings and Glasgow Coma Scale (GCS) scores were obtained within 48 hours of admission to hospital. The sensitivity of the VEEG and QEEG for the prediction of patients with nonviral meningitis (true positives in this context) attained reasonably high values of 70% and 80%, respectively. In contrast, the sensitivity of the GCS was only 38%. Each of the three tests achieved high degrees of consistency in this regard with positive predictive values of 94% or better. The specificity for each of the three tests was high, 100% for the VEEG and the GCS and 82% for the QEEG indicating a high probability for the correct prediction of viral meningitis (true negatives). The consistency of this prediction was, however, poor due to negative predictive values of only 53% for the QEEG, 48% for the VEEG and 32% for the GCS. The QEEG results did not reveal any obvious advantages over the VEEG. Rather the assessment of the occurrence of particular VEEG abnormalities showed that patients with delta abnormalities had a very high probability of nonviral meningitis. At the other end of the spectrum, all normal VEEGs occurred in viral meningitis. In important respects the predictive ability of the EEG was superior to that of the GCS. While there was statistically significant agreement between the VEEG and GCS, the degree of agreement was poor. This study indicates that the EEG is a valuable and probably underestimated test in the acute phase of meningitis and provides complementary information to the GCS.

[Lymphocytic meningitis by mumps virus: epidemiologic, clinical, serologic and evolutive analysis of 28 cases]

BACKGROUND

Mumps is a viral infection which is particularly found in children and adolescents and one of its manifestations is as lymphocytary meningitis. The aim of this study was to analyze the clinical, epidemiologic and serologic characteristics of the cases of meningitis by the mumps virus (MMV) observed during an epidemic of mumps.

SUBJECTS AND METHODS

Twenty-eight cases of MMV diagnosed from December 1, 1994 to August 31, 1995 during an epidemic of mumps in the south of the province of Badajoz (Spain) were analyzed. Demographic, clinical, analytical and evolutive data were obtained.

RESULTS

Cases predominated in the winter and summer in adolescents and youths (mean age 16.9 years) with a male:female relationship of 3:1. On admission most patients presented fever, headache, and parotid hypertrophy. Orchitis was observed in half of the males. No case of encephalitis was seen. Hyperproteinorrhachia was observed in the cephalorrhachidian fluid of 79% of the cases and hypoglucorrhachia was found in only two patients (7%). The course was benign, except in four patients (14%) who had sequelae (headache, unilateral hyperacusia and testicular discomfort).

CONCLUSIONS

The epidemiologic and liquoral data of MMV in adolescents agree with those described in series of children. Nonetheless, the absence of encephalic involvement and the high proportion of orchitis is of note.

Autistic subjects with comorbid epilepsy: a possible association with viral infections

This study evaluates the comorbidity of epilepsy as a variable supporting a viral hypothesis in Autism. Data covering a 30-year period (1960-1989), including general population live births, autistic births, and incidence of viral encephalitis and viral meningitis, were collected for Israel. 290 autistic births were evaluated. The annual birth pattern of subjects with comorbid epilepsy fit the seasonality of viral meningitis. These findings support the role of viral C.N.S. infections in the causality of this disorder.

[Acute severe headache: a subarachnoidal hemorrhage?]

Five patients, three women aged 87, 50, and 31 years, and two men aged 31 and 32 years, presented with severe headache of sudden onset. A sudden onset of unusually severe headache is suggestive of an intracranial haemorrhage or other serious disease, even in the absence of focal neurologic deficits. The diagnoses were subdural haematoma, cerebral venous sinus thrombosis, idiopathic thunderclap headache, subarachnoid haemorrhage, and viral meningitis, respectively. There are no characteristics from history or examination that accurately discriminate among all these causes; idiopathic thunderclap headache and subarachnoid haemorrhage are commonest. Consultation of a neurologist and further ancillary investigations are necessary for proper diagnosis and treatment.

Evaluation of combining upper respiratory tract swab samples with cerebrospinal fluid examination for the diagnosis of enteroviral meningitis in children

In a prospective comparative study, the use of combined analysis of upper respiratory tract swab samples and cerebrospinal fluid (CSF) samples was assessed to improve the detection rate of enteroviral meningitis in children. An enterovirus was detected in 32% of patients with aseptic meningitis when testing CSF samples alone compared with 71.5% when combining CSF and respiratory tract findings. An enterovirus was detected in 17% of respiratory tract samples in an age- and sex-matched control group without meningitis. Thus, combining the examination of upper respiratory tract with CSF findings may improve the detection rate of enteroviral meningitis. Upper respiratory tract samples should be included in the diagnosis scheme to differentiate benign enteroviral meningitis from other life-threatening infections of the central nervous system.

The successful containment of coxsackie B4 infection in a neonatal unit

This report describes the containment of a potential enterovirus epidemic in a neonatal intensive care unit. A case of neonatal enterovirus meningitis and myocarditis was identified. Polymerase chain reaction (PCR) was used to assist in appropriate cohorting of contacts. One further infant became cross-infected with Coxsackie B4. Serum PCR was accurate in detecting the infection in the early stages in this asymptomatic neonate. Neonatal enterovirus infection is relatively rare but has the potential to cause outbreaks in neonatal wards. PCR can be used to diagnose and monitor for cross infection.

Recurrence of ibuprofen-induced aseptic meningitis in an otherwise healthy patient

We report the case of a 74-year-old woman who had three episodes of aseptic meningitis in a period of 20 years. These episodes always occurred a few hours after the assumption of a non-steroidal anti-inflammatory drug (NSAID) per os. Nevertheless, the pharmacological anamnesis did not receive proper attention, neither the first nor the second time, and the meningeal syndrome with aseptic liquor was attributed to a viral aggression. However, when the third episode occurred, due to the strict time correlation between the assumption of the drug and the occurrence of symptoms, both the results of the liquoral analysis and the anamnestic records allowed recognition of ibuprofen as the cause of acute meningitis.

[Procalcitonin, a marker of bacterial meningitis in children]

Procalcitonin (PCT) is a new marker connected to systemic bacterial infection. Blood values are parallel to the severity of the disease. In the present Knowledge on PCT, the usefulness is focused on acute pediatric pathology, ICU, and the follow up of grafts and surgery. This paper dwells on the interest in the differential diagnosis for meningitis (viral versus bacterial). At the opposite of CRP and IL6, a very clear cut off for all the cases has been found. The cut off in this study is about 2-3 micrograms/l. PCT, at the difference of cytokines is a very stable molecule in the blood sample. Also a very small quantity of serum (or plasma) 20 microliters is sufficient for one assay. In the future, a point of care assay will be available and should be very interesting in the emergency wards (pediatric or adult ICU). The origin of PCT seems to be--but perhaps not exclusively--mononuclear cells. The absence of an animal model (except monkeys) is actually a difficulty to progress.

[Mollaret's meningitis. A rare disease with a characteristic presentation]

We report a case of a 72-year-old woman, who within a six-year period had four episodes of Mollaret's meningitis. Lumbar punctures during each episode revealed moderate leukocytosis with large mononuclear cells. Characteristic manifestations and differential diagnosis are briefly reviewed. There is no established therapy for Mollaret's meningitis. Extensive investigations failed to reveal a specific cause of this disease, although there is some evidence for infection caused by Herpes simplex-virus.

[Recurrent Mollaret's meningitis of herpetic origin]

BACKGROUND

Benign recurrent meningitis, or Mollaret's meningitis, is an uncommon disease whose viral origin was long unidentified. Since 1991, about twenty cases have been reported in patients with herpes infection.

CASE REPORT

A female patient had experienced repeated episodes of spontaneous meningitis since 1983. The episodes resolved spontaneously and no etiology had been identified. A spinal tap was performed when the patient was again hospitalized a new episode of meningitis and PCR amplification of the herpes simplex virus type 2 (HSV 2) was positive. The patient was given long term acyclovir per os. A new spinal tap after resolution of the meningitis episode was PCR HSV2 negative.

DISCUSSION

HSV2 infection is one of the known causes of Mollaret's meningitis. Long-term antiviral therapy appears to prevent recurrence as was observed in our patient.

Herpes simplex virus type 2 DNA detected in cerebrospinal fluid of 9 patients with Mollaret's meningitis

We present clinical and virological data on 9 patients, 7 women and 2 men aged 31-56 years, with recurrent aseptic meningitis (Mollaret's meningitis). Polymerase chain reaction detected Herpes simplex virus type 2 DNA in cerebrospinal fluid samples from all patients collected during their latest attacks of meningitis. Six patients had no history of genital herpes. Only 1 patient was offered prophylactic antiviral treatment during the study period (45 months).

[Quantitative levels of serum amyloid A protein and other proteins in cerebrospinal fluid and serum of patients with meningitis]

Serum amyloid A protein (SAA), a putative precursor of the AA protein which constitutes amyloid fibrils in secondary amyloidosis, is evaluated as a sensitive acute-phase reactant in serum. At present, SAA concentration in serum is determined by latex nephelometry, but this assay cannot detect SAA in the low concentration range lower than 10 ng/ml. We have developed a sensitive enzyme immunoassay (EIA) for determining low concentrations of SAA. The assay is reproducible, reliable and requires no pretreatment of specimen prior to assay. We measured levels of SAA by this EIA in both cerebrospinal fluid (CSF) and serum of patients with suspected meningitis, measured also levels of albumin, alpha 2 macroglobulin and C-reactive protein (CRP) to investigate if these protein levels are useful for differential diagnoses of meningitis and for indicators damage of blood-CSF barrier. The SAA reference value in CSF is 3.99 +/- 1.74 ng/ml (mean +/- SD for nonmeningitis patients). The CRP concentration in CSF in bacterial meningitis was much higher than in viral meningitis, but CRP in CSF was also high in bacterial infection other than meningitis. On the other hand, SAA concentration in CSF in these patients with any meningitis are significantly higher than the reference values of SAA (p < 0.001). However, the differences in SAA concentrations among the three types (bacterial, viral and mycotic meningitis) of meningitis were not significant.

[Herpes simplex and lymphocytic choriomeningitis viruses in infections of the central nervous system--clinical and cerebrospinal fluid characteristics]

INTRODUCTION

A great number of various viruses are stated as the cause of acute infections and damages of the central nervous system. In most cases these are minor damages which exhibit as meningeal syndrome and a specific finding in the cerebrospinal fluid. According to the dominant location, central nervous system infections can take a form of meningitis, encephalitis or myelitis. Since the inflammatory process of the meninges can not be separated from the inflammatory process of the brain, we usually speak of meningoencephalitis. The etiological diagnosis of meningitis and encephalitis is established by isolating the virus from the cerebrospinal fluid and by finding the presence of the specific antibodies in the blood and in the cerebrospinal fluid. The most common causes of the viral meningitis are Enteroviruses, the Mumps virus, Arthropode borne viruses, the Herpes viruses, Adeno viruses and the Lymphocytic choriomeningitis virus. The aim of our study was to establish the correlation between the clinical features and immunological and cerebrospinal fluid changes and the degree of the damage to the blood-brain barrier during the infections of the central nervous system, caused by the Herpes Simplex virus and the Lymphocytic choriomeningitis virus.

MATERIAL AND METHODS

From a group of 103 patients, who had been treated for viral meningitis and meningoencephalitis, a group of 27 patients with established specific viral etiology--Herpes Simplex virus and Lymphocytic choriomeningitis virus, had been taken into the account. Herpes Simplex infection had been proven by the complement binding reaction and the neutralisation test of the even samples of serum. The diagnosis of Lymphocytic choriomeningitis was confirmed by the immunofluorescence test of the pharynx swabs and cerebrospinal fluid. The clinical features, such as body temperature, encephalitic signs, and electroencephalographic findings had been followed and compared.

RESULTS

Herpes Simplex infection had been found in 20 patients, Lymphocytic choriomeningitis had been proven in 7 patients. All the patients had increased body temperature. Only four of the patients exhibited encephalitic signs, all infected by the Herpes Simplex virus. Patients from the Herpes Simplex group showed various degrees of consciousness disturbances, ranging from somnolence to coma, while the Lymphocytic choriomeningitis patients exhibited none. Higher pleocytosis and protein level had been found in the Lymphocytic choriomeningitis group.

DISCUSSION

Viral diseases of the central nervous system are the result of the direct damage of the brain and meninges by the virus and immunological processes. Herpes Simplex meningitis usually has a good prognosis. Lymphocytic choriomeningitis has longer course of the disease and exhibits more severe clinical features.

CONCLUSION

In cases of the central nervous system infections, caused by Herpes Simplex virus or Lymphocytic choriomeningitis virus, the correlation between the severeness of clinical features and the degree of damage of the blood-brain barrier, the level of pleocytosis and the increase of the cerebrospinal fluid proteins had been established.

Genital recurrent infection occurring 6 months after meningitis due to the same herpes simplex virus type 2 (HSV-2) strain evidence by restriction endonuclease analysis

Herpes simplex virus type 2 (HSV-2) is more often sexually transmitted and associated with genital recurrent infection. However, HSV-2 neurological manifestations such as meningitis were already reported. We describe a case of meningitis due to HSV-2, preceded by signs suggesting a common cystitis, in a woman with no history of primary or recurrent genital infection. Six months later genital herpetic lesions occurred. One HSV-2 strain was obtained from cerebrospinal fluid (CSF) and another from genital lesions. The molecular comparative analysis using restriction endonuclease digestion patterns showed the similarity of the two strains. Our report illustrates that HSV-2 infections are underdiagnosed and that molecular techniques can be of value in clarifying the physiopathology of HSV diseases.

Herpes simplex virus

CNS infections caused by human herpesvirus 1 and human herpesvirus 2-herpes simplex virus type 1 and herpes simplex virus type 2--are reviewed. The major diseases associated with these viruses are meningitis and encephalitis. Two forms of encephalitis are known, neonatal encephalitis and encephalitis occurring after the neonatal period. Both diseases are associated with high mortality and morbidity and require prompt diagnosis and aggressive antiviral chemotherapy. Methods for the specific diagnosis of these infections are reviewed and the value of intrathecal antibody assay and nucleic acid amplification techniques are emphasised.

Molecular typing of enteroviruses: current status and future requirements. The European Union Concerted Action on Virus Meningitis and Encephalitis

Human enteroviruses have traditionally been typed according to neutralization serotype. This procedure is limited by the difficulty in culturing some enteroviruses, the availability of antisera for serotyping, and the cost and technical complexity of serotyping procedures. Furthermore, the impact of information derived from enterovirus serotyping is generally perceived to be low. Enteroviruses are now increasingly being detected by PCR rather than by culture. Classical typing methods will therefore no longer be possible in most instances. An alternative means of enterovirus typing, employing PCR in conjunction with molecular genetic techniques such as nucleotide sequencing or nucleic acid hybridization, would complement molecular diagnosis, may overcome some of the problems associated with serotyping, and would provide additional information regarding the epidemiology and biological properties of enteroviruses. We argue the case for developing a molecular typing system, discuss the genetic basis of such a system, review the literature describing attempts to identify or classify enteroviruses by molecular methods, and suggest ways in which the goal of molecular typing may be realized.

[Meningitis by enterovirus in pediatrics. Clinical characteristics and virologic diagnosis]

BACKGROUND AND METHODS

With the aim of knowing the etiology of aseptic meningitis (pleocytosis in LCR with negative bacterial culture and positive or negative virus culture or without pleocytosis with viral culture in positive LCR), 48 children attending the Emergency Department of our hospital from June to December, 1995 were prospectively studied. Pharyngeal and rectal swab, LCR for bacteria and virus and blood cultures were carried out. The samples were inoculated in fibroblasts MRC-5, RD and BGM. The cytopathic effect was identified by immunofluorescence. Typing was performed in the National Center of Public Health Care Microbiology, Virology and Immunology in Majadahonda (Spain).

RESULTS

Isolation of the virus was positive in 40/48 (83.3%) of the children: in 17 (35.5%) of LCR and the remaining 23/40 (47.9%) of pharyngeal and/or rectal swab. In all the cases the cytopathic effect was detected in MRC-5. The viruses found were echovirus 30 and 5. A greater incidence of the disease was observed in November and December.

CONCLUSIONS

Meningitis by enterovirus is frequent in our area. Culture of the virus in LCR, the pharynx and stools is useful on suspicion of aseptic meningitis since the virus may be isolated from LCR in more than one third of the patients. Serotyping aids in surveilling the appearance of outbreaks and to know the predominant viruses. Cell culture is the diagnostic treatment of choice, but has a low sensitivity and is slow. The application of other techniques such as PCR which have a greater sensitivity and with high specificity for the diagnosis of these infections is necessary.