Cerebrospinal Fluid Analysis.

Cerebrospinal fluid (CSF) analysis is a diagnostic tool for many conditions affecting the central nervous system. Urgent indications for lumbar puncture include suspected central nervous system infection or subarachnoid hemorrhage. CSF analysis is not necessarily diagnostic but can be useful in the evaluation of other neurologic conditions, such as spontaneous intracranial hypotension, idiopathic intracranial hypertension, multiple sclerosis, Guillain-Barré syndrome, and malignancy. Bacterial meningitis has a high mortality rate and characteristic effects on CSF white blood cell counts, CSF protein levels, and the CSF:serum glucose ratio. CSF culture can identify causative organisms and antibiotic sensitivities. Viral meningitis can present similarly to bacterial meningitis but usually has a low mortality rate. Adjunctive tests such as CSF lactate measurement, latex agglutination, and polymerase chain reaction testing can help differentiate between bacterial and viral causes of meningitis. Immunocompromised patients may have meningitis caused by tuberculosis, neurosyphilis, or fungal or parasitic infections. Subarachnoid hemorrhage has a high mortality rate, and rapid diagnosis is key to improve outcomes. Computed tomography of the head is nearly 100% sensitive for subarachnoid hemorrhage in the first six hours after symptom onset, but CSF analysis may be required if there is a delay in presentation or if imaging findings are equivocal. Xanthochromia and an elevated red blood cell count are characteristic CSF findings in patients with subarachnoid hemorrhage. Leptomeningeal carcinomatosis can mimic central nervous system infection. It has a poor prognosis, and large-volume CSF cytology is diagnostic.

Adenovirus Infection-associated Central Nervous System Disease in Children.

BACKGROUND: Adenovirus (Adv) is a frequent etiology of acute respiratory tract infections. Although rare, neurologic manifestations are known to occur during Adv infection. METHODS: We retrospectively analyzed clinical, laboratory, outcome and the relationship between clinical characteristics and viral detection results in the cerebrospinal fluid (CSF) in children with Adv-associated central nervous system (CNS) dysfunction. RESULTS TWENTYONE: (1.5%) cases had Adv-associated CNS manifestations. The median age was 1.4 years and 20 (95%) were less than 5 years of age. Six (28%) were male. The most frequently cited CNS symptoms were altered consciousness (100%) and seizure (14.3%). Fourteen cases (73.7%) had abnormal electroencephalogram examination and 6 cases (37.5%) had abnormal imaging. None of the patients had received cidofovir administration. Twenty children recovered without sequelae and 1 patient died of respiratory failure. Patients with positive Adv polymerase chain reaction (n = 11) presented lower onset age compared with that of patients with negative Adv polymerase chain reaction (n = 10) in the CSF. Clinical manifestation, laboratory findings, imaging studies and electroencephalogram showed no significant difference between the 2 groups. CONCLUSION: Adv is a rare cause of CNS disease in children, mainly causing altered consciousness. Adv was detected in more cases in the respiratory tract than the CSF, but the majority of patients had the virus detected in both. The lack of Adv in the CSF does not exclude CNS involvement. Furthermore, the viral detection results in the CSF do not seem useful as an indicator of the severity of CNS disease.

[A Seven-Year Evaluation of Viral Central Nervous System Infections]. / Viral Etkenlere Bagli Santral Sinir Sistemi Enfeksiyonlarinin Yedi Yillik Degerlendirmesi.

Identification of viral agents causing central nervous system (CNS) infections increased by the application of nucleic acid tests. In this study, the results of polymerase chain reaction (PCR) for viral agents were evaluated in cerebrospinal fluid (CSF) samples taken from patients with CNS infection. CSF samples taken from 1185 patients between 2010 and 2017 were tested for the presence of Herpes simplex virus (HSV) type 1 and 2, Varicella Zoster virus (VZV), Epstein-Barr virus (EBV), cytomegalovirus (CMV), adenovirus ve enterovirus by PCR in Dokuz Eylul University Hospital. Tests were performed according to the clinicians' orders and results were evaluated retrospectively. The number of tests performed were 1038 for HSV, 882 for adenovirus, 865 for enterovirus, 496 for VZV, 100 for EBV and 92 for CMV. Commercial tests were used for EBV, CMV (Artus QS-RGQ Kits, Qiagen, Germany) and enterovirus (GeneXpert, Cepheid, USA) while the other viruses (HSV, VZV, adenovirus) were tested by in-house real-time PCR assays. Ninety-one CSF (7.7%) samples were positive. The mean age was 13 (<1 to 76 years) while median was seven. The most frequently detected pathogens were enterovirus (63/91, 69%) and HSV-1 (14/91,15%). The number of patients positive for adenovirus, VZV, EBV and CMV were five, four, three and two, respectively. In one patient, both enterovirus (Ct: 29.5) and EBV (Ct: 38.53) were positive. The number of positive samples were increased in summer months. Enterovirus RNA positive patients (n= 60/63, 95.2%) were ≤ 18 years old while 29% were younger than one year of age. Enterovirus positive samples peaked in 2012 and 2014 and detected mainly in summer (60.3%) and autumn (20.6%) months. VZV was mostly detected in patients greater than 65 years of age. Mean Ct of the positive reactions was 31.87 ± 3.5 (22.88-40.32). The lowest and the highest Ct values were detected in HSV-1 assay. The mean Ct value of enterovirus assay (30.4; 25.7-35.9) was lower than the other pathogens' values. In the seven-year period, 7.7% of the1185 patients' CSF samples were positive for viral nucleic acids. As expected, enteroviruses were the most common pathogens in children and detected mainly in summer-autumn period. Syndromic approach in CNS infections could increase the viral pathogen detection.

[Evaluation of viral etiology in central nervous system infections from a university hospital point of view in Izmir based on seven years data]. / Santral sinir sistemi enfeksiyonlarinda viral etiyolojinin Izmir'de bir üniversite hastanesinin yedi yillik verileri üzerinden degerlendirilmesi.

The serious diseases of the central nervous system (CNS); encephalitis and meningitis, have high mortality and morbidity rate especially not diagnosed and treated in time. Nucleic acid testing (NAT) is the tool of choice for viral diagnosis in CNS infections. In this study, viral etiological agents found in cerebrospinal fluid (CSF) samples sent to our university hospital virology laboratory for laboratory diagnosis of CNS infections were retrospectively evaluated and results were compared with other reports from our country. Viral etiological agents found in cerebrospinal fluid (CSF) samples sent to Ege University Faculty of Medicine Department of Medical Microbiology Virology Laboratories for laboratory diagnosis of CNS infection between 01.01.2009-31.12.2015 were evaluated retrospectively. A total of 3778 CSF tests were performed for cell culture of enterovirus (EV) in 487 samples and 3291 tests for nucleic acid testing (NAT) by real time polymerase chain reaction (PCR) in herpes simplex virus 1 (HSV1), herpes simplex virus 2 (HSV2), varicella zoster virus (VZV), Epstein-Barr virus (EBV), cytomegalovirus (CMV), human herpes virus 6 (HHV6) and EV. VZV and EV NAT's were performed during the last one and five years period, respectively. NAT positive results for HSV1, HSV2, CMV, EBV, VZV, HHV6 and EV were 1.80% (24/1333), 0.08% (1/1333), 3.28% (19/580), 4.35% (22/506), 0.46% (1/216), 1.05% (5/478) and 3.37% (6/178), respectively. EV was isolated in 30 (6.20%) of 487 CSF samples by viral culture. Positive samples were mainly from pediatric, neurology and infectious diseases clinics as expected. The number of higher positive results were found in samples sentin december (35.3%), july (12.9%) and november (10.6%). Overall 80% of positive samples belonged to patients over 18 years old. When the results of other studies reported from Turkey are examined, although the positivity rates are generally similar, it is seen that the rates specific to certain factors are higher in selected smaller patient groups like HSV1 and EV. Rapid nucleic acid tests like multiplex PCR and microarray will provide more practical and effective laboratory diagnosis approach in CNS infections, since many more microorganisms may be causative agents.

Divergent cerebrospinal fluid cytokine network induced by non-viral and different viral infections on the central nervous system.

BACKGROUND: Meningoencephalitis is one of the most common disorders of the central nervous system (CNS) worldwide. Viral meningoencephalitis differs from bacterial meningitis in several aspects. In some developing countries, bacterial meningitis has appropriate clinical management and chemotherapy is available. Virus-associated and virus not detected meningoencephalitis are treatable, however, they may cause death in a few cases. The knowledge of how mediators of inflammation can induce disease would contribute for the design of affordable therapeutic strategies, as well as to the diagnosis of virus not detected and viral meningoencephalitis. Cytokine-induced inflammation to CNS requires several factors that are not fully understood yet. METHODS: Considering this, several cytokines were measured in the cerebrospinal fluid (CSF) of patients with undiagnosed and viral meningoencephalitis, and these were correlated with cellularity in the CSF. RESULTS: The results demonstrate that an altered biochemical profile alongside increased cellularity in the cerebrospinal fluid is a feature of patients with meningoencephalitis that are not associated with the detection of virus in the CNS (P < 0.05). Moreover, HIV-positive patients (n = 10) that evolve with meningoencephalitis display a distinct biochemical/cytological profile (P < 0.05) in the cerebrospinal fluid. Meningoencephalitis brings about a prominent intrathecal cytokine storm regardless of the detection of virus as presumable etiological agent. In the case of Enterovirus infection (n = 13), meningoencephalitis elicits robust intrathecal pro-inflammatory cytokine pattern and elevated cellularity when compared to herpesvirus (n = 15) and Arbovirus (n = 5) viral infections (P < 0.05). CONCLUSION: Differences in the cytokine profile of the CSF may be unique if distinct, viral or presumably non-viral pathways initially trigger the inflammatory response in the CNS.

Viral pathogens in children hospitalized with features of central nervous system infection in a malaria-endemic region of Papua New Guinea.

BACKGROUND: Viral central nervous system (CNS) infections are common in countries where malaria is endemic but, due to limited laboratory facilities, few studies have systematically examined the prevalence and clinical consequences of the presence of viruses in cerebrospinal fluid (CSF) from children with suspected CNS infection. METHODS: We performed a prospective study of Papua New Guinean children hospitalized with signs and symptoms of CNS infection. CSF samples from 300 children without proven bacterial/fungal meningitis were analyzed for human herpes viruses (HHV), picornaviruses, influenza, adenoviruses, flaviviruses and bacteria. RESULTS: Fifty-five children (18%) had viral (42), bacterial (20) or both viral and bacterial (7) nucleic acids (NA) identified in their CSF. Human herpes viruses accounted for 91% of all viruses found. The identification of viral or bacterial NA was not associated with any characteristic clinical features. By contrast, malaria was associated with increased identification of viral and bacterial NA and with impaired consciousness, multiple convulsions and age. Malaria was also inversely associated with an adverse outcome. Amongst children with HHV infection, those with HHV-6 and -7 were younger, were more likely have impaired consciousness and had a higher proportion of adverse outcomes than children with CMV. Dengue and enteroviral infections were infrequent. Adenoviral and influenza infections were not identified. CONCLUSION: Infections with HHV-6, HHV-7, dengue and enterovirus have the potential to cause serious CNS disease in young PNG children. However most HHVs in this malaria-endemic setting should be considered to be the result of reactivation from a latent reservoir without clinical sequelae.

Epstein-Barr virus (EBV) load in cerebrospinal fluid and peripheral blood of patients with EBV-associated central nervous system diseases after allogeneic hematopoietic stem cell transplantation.

BACKGROUND: To evaluate the diagnostic and prognostic utility of monitoring the Epstein-Barr virus (EBV) load in the cerebrospinal fluid (CSF) and peripheral blood for the patients with EBV-associated central nervous system (CNS) diseases after allogeneic hematopoietic stem cell transplantation (allo-HSCT), 172 patients undergoing allo-HSCT were enrolled in the study. METHODS: The EBV DNA levels of blood were monitored regularly in recipients of transplants for 3 years post transplantation. The EBV DNA levels of CSF were monitored in patients with EBV-associated CNS diseases before the treatment and at different points following the treatment. RESULTS: Post-transplant EBV-associated diseases developed in 27 patients, including 12 patients with EBV-associated CNS diseases. The 3-year cumulative incidences of EBV-associated diseases and EBV-associated CNS diseases were 19.5 ± 3.5% and 8.6 ± 2.4%, respectively. Patients with EBV-associated diseases showed higher loads of EBV DNA in their blood compared with patients with EBV DNA-emia. No difference was seen between the EBV DNA levels of blood in patients with CNS involvement and patients without CNS involvement. The EBV DNA loads of blood increased 3-14 days before the clinical manifestations of EBV-associated diseases emerged. The EBV DNA loads of CSF were higher than that of blood in patients with EBV-associated CNS diseases. In 12 patients with EBV-associated CNS diseases, EBV DNA levels were declining in both blood and CSF with the control of diseases, and the EBV DNA loads of CSF decreased faster than that of blood in 5 patients who responded to treatment, and the EBV DNA levels of CSF increased in 5 patients who were unresponsive to treatment. On multivariate analysis, the use of anti-thymocyte globulin and intensified conditioning regimens were independent risk factors for EBV-associated diseases and EBV-associated CNS diseases. CONCLUSIONS: EBV-associated CNS diseases are not rare after allo-HSCT. The EBV DNA loads of CSF could act as an important indicator, but the EBV DNA loads of blood could not, for the diagnosis, prognosis, and therapeutic evaluation of EBV-associated CNS diseases.

Viral CNS infections in children from a malaria-endemic area of Malawi: a prospective cohort study.

BACKGROUND: Fever with reduced consciousness is an important cause of hospital admission of children in sub-Saharan Africa, with high mortality. Cerebral malaria, diagnosed when acute Plasmodium falciparum infection and coma are recorded with no other apparent reason, is one important cause. We investigated whether viruses could also be an important cause of CNS infection in such patients, and examined the relative contribution of viral pathogens and malaria parasitaemia. METHODS: We did a prospective cohort study in Blantyre, Malawi. From March 1, 2002, to Aug 31, 2004, we enrolled children aged between 2 months and 15 years who were admitted to hospital with suspected non-bacterial CNS infections. Children with a cerebrospinal fluid (CSF) white cell count of less than 1000 cells per µL and negative bacterial microscopy and culture were deemed to have suspected viral CNS infection. Blood was examined for asexual forms of P falciparum. PCR was done on CSF or on post-mortem brain biopsy specimens to detect 15 viruses known to cause CNS infection. FINDINGS: Full outcome data were available for 513 children with suspected viral CNS infection, of whom 94 (18%) died. 163 children (32%) had P falciparum parasitaemia, of whom 34 (21%) died. At least one virus was detected in the CNS in 133 children (26%), of whom 43 (33%) died. 12 different viruses were detected; adenovirus was the most common, affecting 42 children; mumps, human herpes virus 6, rabies, cytomegalovirus, herpes simplex virus 1, and enterovirus were also important. 45 (9%) of the 513 children had both parasitaemia and viral infection, including 27 (35%) of 78 diagnosed clinically with cerebral malaria. Children with dual infection were more likely to have seizures than were those with parasitaemia alone, viral infection only, or neither (p<0·0001). 17 (38%) of the 45 children with dual infection died, compared with 26 (30%) of 88 with viral infection only, 17 (14%) of 118 with parasitaemia only, and 34 (13%) of 262 with neither (p<0·0001). Logistic regression showed children with a viral CNS infection had a significantly higher mortality than did those who did not have a viral CNS infection (p=0·001). INTERPRETATION: Viral CNS infections are an important cause of hospital admission and death in children in Malawi, including in children whose coma might be attributed solely to cerebral malaria. Interaction between viral infection and parasitaemia could increase disease severity. FUNDING: Wellcome Trust, US National Institutes of Health, and UK Medical Research Council.

Analysis of correlation between cerebrospinal fluid and plasma HIV-1 RNA levels in patients with neurological opportunistic diseases / Análise da correlação entre os níveis de RNA do HIV-1 no líquido cefalorraquidiano e plasma em pacientes com doença neurológica oportunista

The question of whether HIV-1 RNA in cerebrospinal fluid (CSF) is derived from viral replication in the central nervous system or simply reflects the transit of infected lymphocytes from the blood compartment has long been a matter of debate. Some studies found no correlation between CSF and plasma viral load, whereas others did. The lack of a correlation between the two compartments suggests that the presence of HIV-1 RNA is not simply due to the passive passage of the virus from blood to CSF but rather due to intrathecal replication. To evaluate the correlation between plasma and CSF HIV-1 RNA levels and to identify situations in which there is no correlation between the two compartments, seventy patients were prospectively studied. The association between CSF and plasma viral load was evaluated in the total population and in subgroups of patients with similar characteristics. A correlation between the CSF and plasma compartments was observed for patients undergoing highly active antiretroviral therapy (HAART), those with a CD4 T lymphocyte count lower than 200 cells/mm³, and those with increased CSF protein content. On the other hand, no correlation was observed for patients without adequate virological control, who had a CD4 count higher than 200 cells/mm³ and who did not use HAART. The correlation between the two compartments observed in some patients suggests that CSF HIV-1 RNA levels may reflect plasma levels in these subjects. In contrast, the lack of a correlation between the two compartments in patients who were not on HAART and who had normal CSF proteins and a poor virological control possibly indicates compartmentalization of the virus in CSF and, consequently, plasma-independent intrathecal viral replication.

Tem sido objeto de debate a questão se o RNA do HIV-1 no líquido cefalorraquidiano (LCR) é derivado da replicação viral no sistema nervoso central ou simplesmente reflete o tráfego de linfócitos infectados do compartimento sanguíneo. Alguns estudos não mostraram correlação entre a carga viral do plasma e LCR, mas outros sim. A falta de correlação entre os dois compartimentos sugere que a presença de RNA do HIV-1 não é simplesmente devido à passagem do vírus do plasma para o LCR, mas sim a uma replicação intratecal. Para avaliar a correlação entre os níveis de RNA do HIV-1 no plasma e no LCR e tentar identificar situações, na qual, não existe a correlação entre os dois compartimentos avaliaram-se setenta pacientes prospectivamente. A associação entre a carga viral do LCR e plasma foi avaliada na população total e em subgrupos de pacientes com características similares. A correlação entre os dois compartimentos foi observada em pacientes que estavam em uso da terapia antiretroviral (HAART), naqueles que tinham contagem de linfócitos CD4 menor que 200 céls/mm³ e naqueles com aumento da concentração de proteínas no LCR. Por outro lado, não houve correlação para os pacientes que não tinham um controle virológico adequado, os que tinham contagem de CD4 maior que 200 céls/mm³ e aqueles que não estavam usando HAART. A correlação entre os dois compartimentos observada em alguns pacientes sugere que os níveis de RNA do HIV-1 no LCR podem refletir os níveis plasmáticos nestes pacientes. E a falta de correlação ente os dois compartimentos em pacientes que não usavam HAART, nos que tinham uma concentração de proteínas no LCR normal, e nos que não apresentavam bom controle virológico, indica provavelmente a compartimentalização do vírus no LCR e consequentemente replicação viral intratecal independente da do plasma.

Single tube multiplex real-time PCR for the rapid detection of herpesvirus infections of the central nervous system.

Human herpesvirus infection of immunocompromised hosts may lead to central nervous system (CNS) infection and diseases. In this study, a single tube multiplex real-time PCR was developed for the detection of five herpesviruses (HSV-1, HSV-2, VZV, EBV and CMV) in clinical cerebrospinal fluid (CSF) specimens. Two primer pairs specific for the herpesvirus polymerase gene and five hybridization probe pairs for the specific identification of the herpesvirus types were used in a LightCycler multiplex real-time PCR. A singleplex real-time PCR was first optimized and then applied to the multiplex real-time PCR. The singleplex and multiplex real-time PCRs showed no cross-reactivity. The sensitivity of the singleplex real-time PCR was 1 copy per reaction for each herpesvirus, while that of the multiplex real-time PCR was 1 copy per reaction for HSV-1 and VZV and 10 copies per reaction for HSV-2, EBV and CMV. Intra and inter-assay variations of the single tube multiplex assay were in the range of 0.02%-3.67% and 0.79%-4.35%, respectively. The assay was evaluated by testing 62 clinical CSF samples and was found to have equivalent sensitivity, specificity and agreement as the routine real-time PCR, but reducing time, cost and amount of used sample.

Negative association of Epstein-Barr virus or herpes simplex virus-1 with tumefactive central nervous system inflammatory demyelinating disease.

Central nervous system (CNS) demyelination has been suggested to be associated with infections caused by the Epstein-Barr virus (EBV) or herpes simplex virus (HSV)-1. CNS inflammatory demyelinating disease (IDD) rarely presents as a large lesion. We evaluated samples of serum and cerebrospinal fluid (CSF) by enzyme-linked immunosorbent assay to detect recent infection with these viruses and analyzed CSF and brain specimens by polymerase chain reaction (PCR) or immunohistochemical studies for evidence of these viruses in three patients with biopsy-proven CNS IDD. The results of PCR tests for EBV and HSV in CSF or brain specimens were negative. Elevated anti-EBV or -HSV antibody levels were not found in serum or CSF in any patient. Immunohistochemical studies showed that IDD lesions were negative for latent membrane protein (LMP)-1, Epstein-Barr nuclear antigen (EBNA)-2, and EBNA noncoding RNA (EBER)-1. These results suggest a negative association between CNS IDD and EBV or HSV.

Análise molecular de patógenos pela reação em cadeia da polimerase no líquido cefalorraquiano de pacientes infectados com HIV / Molecular analysis of pathogens in cerebrospinal fluid by the polymerase chain reaction in HIV-infected patients

Introdução: A reação em cadeia da polimerase (PCR) foi teste de grande impacto no diagnóstico das meningites e encefalites linfocíticas durante a última década. Esse método foi extensivamente usado no diagnóstico das infecções do sistema nervoso central (SNC), devido a sua habilidade em detectar amostras mínimas de DNA-alvo no líquido cefalorraquiano. Objetivo: O objetivo deste estudo foi identificar a prevalência dos patógenos oportunistas responsáveis por causar problemas neurológicos em pacientes infectados com o vírus da imunodeficiência humana (HIV) e avaliar sua associação com os achados clínicos, laboratoriais e da tomografia computadorizada cerebral (TCC). Pacientes e métodos: Um estudo transversal foi realizado em 203 amostras de líquido cefalorraquiano (LCR) de pacientes do sul do Brasil infectados com HIV e com aparente encefalite e meningite linfocíticas. As amostras foram analisadas para os seguintes agentes pelo método da reação em cadeia da polimerase "nested" ou dupla (N-PCR): citomegalovírus, vírus do Epstein-Barr, vírus do herpes simplex tipos 1 e 2, vírus da varicella zoster, vírus do herpes humano tipo 6, vírus JC, Toxoplasma gondii e micobactérias. Resultado: Pelo menos um patógeno foi encontrado em 77 (38%) dos indivíduos. O Epstein-Barr foi o mais prevalente, com 40 casos (19,7%), seguido pelo citomegalovívus, com 12 casos (15%) e pelo vírus JC, em 9 casos (4,4%). Um N-PCR positivo mostrou associação com aumento de proteínas e de celularidade (P=0,001), meningismo (P=0,017) e tomografia computadorizada anormal (P=0,006). Conclusão: O painel de PCR empregado foi efetivo na identificação de infecções neurológicas severas em pacientes HIV positivos (AU)

Introduction: Polymerase chain reaction (PCR) has had great impact on the diagnosis of lymphocytic meningitis and encephalitis over the last decade. It has been extensively used in the diagnosis of central nervous system (CNS) infections for its ability to detect small amounts of target DNA in the cerebrospinal fluid (CSF). Objective: The aim of this study was to identify the prevalence of opportunistic pathogens responsible for neurological disorders in patients infected with human immunodeficiency virus (HIV) and to evaluate its association with clinical, laboratory and cerebral computed tomography (CCT) findings. Patients and methods: A cross-sectional study was performed on 203 cerebrospinal fluids (CSF) from HIV-infected patients from Southern Brazil, with apparent lymphocytic meningitis and encephalitis. CSF samples were analyzed with probes for cytomegalovirus, Epstein-Barr virus, herpes simplex virus types 1 and 2, varicella zoster virus, human herpes virus type 6, JC virus, Toxoplasma gondii and mycobacterium in nested polymerase chain reaction (N-PCR). Results: At least one pathogen was found in 77 (38.0%) individuals. Epstein-Barr virus was the most prevalent with 40 cases (19.7%), followed by cytomegalovirus with 12 cases (5.9%) and JC virus with 9 cases (4.4%). Positive NPCR showed association with high spinal fluid protein and cell count (P=0.001), meningism (P=0.017) and abnormal CCT (P=0.006). Conclusion: The PCR panel used was effective in screening several neurological infections in HIV positive patients (AU)

Immunophenotypic patterns of T-cell activation in neuroinflammatory diseases.

OBJECTIVES: We aimed to gain insights into the pathogen-specific differences in early adaptive immune responses following central nervous system infections with Borrelia burgdorferi and viral pathogens by studying the immunophenotypic patterns of T-cell activation. Moreover, we wished to determine whether the expression of T-cell activation markers reflects disease activity in multiple sclerosis (MS). METHODS: Proportions of cerebrospinal fluid T-cells expressing the markers HLA-DR, CD25 and CD38 were determined in patients with MS (n = 40), acute viral meningomyeloradiculoneuritis (VID, n = 26), early neuroborreliosis (NB, n = 23) and non-inflammatory neurologic diseases (n = 51) by using flow cytometry. In relapsing-remitting MS, disease activity was assessed by clinical examination and magnetic resonance imaging. RESULTS: For each of the surface markers that were examined, significant differences in T cell proportions were found between patient groups. The proportion of HLA-DR+ T cells was higher and that of CD25+ T cells lower in NB compared with VID. These differences were attributable only to the early phase of the disease (< or = 6 days after symptom onset). Among MS patients, there was a trend for higher proportions of T cells expressing activation markers in patients with gadolinium-enhancing lesions. CONCLUSIONS: The decreased CD25 expression in NB may reflect immunomodulatory effects of B. burgdorferi facilitating persistent infection. Larger prospective studies of T-cell activation markers for ascertaining the association between cellular markers and clinical surrogates of disease activity in MS are warranted.

HIV-1 RNA levels in cerebrospinal fluid and plasma and their correlation with opportunistic neurological diseases in a Brazilian AIDS reference hospital

INTRODUÇÃO: Os níveis de RNA do HIV-1 no plasma refletem a replicação viral sistêmica e a replicação no sistema nervoso central pode ocorrer independentemente da infecção sistêmica, mas a utilidade da medida destes níveis no líquido cefalorraqueano (LCR) permanece indefinida. OBJETIVO: Comparar os níveis de RNA do HIV-1 no LCR e plasma de pacientes sem doenças neurológicas e com diferentes doenças neurológicas, bem como correlacionar estes níveis com a sua evolução e o uso de antiretrovirais. MÉTODO: Foram avaliados 97 pacientes com suspeita de doença neurológica que realizaram punção lombar e que foram divididos em dois grupos: sem doenças neurológicas (23) e com doenças neurológicas (74). Metodologia NASBA foi usada para quantificação do RNA do HIV-1. RESULTADOS: A mediana da carga viral do LCR foi maior em pacientes com neurotoxoplasmose, neurocriptococose, demência pelo HIV e doença neurológica sem etiologia definida quando comparada aos pacientes sem doenças neurológicas. Não houve diferença da carga viral do plasma entre os pacientes com e sem doença neurológica. A mediana da carga viral do plasma e LCR foi maior nos pacientes que faleceram em relação aos tratados com sucesso. A carga viral do LCR e plasma foi menor nos pacientes com doenças oportunísticas que usavam HAART em relação aos que não a usavam. CONCLUSÃO: A carga viral no LRC foi maior nos pacientes com qualquer doença neurológica em relação aos sem doenças neurológicas, mas isto não ocorreu no plasma, sugerindo que doença neurológica influencia mais o compartimento do LCR que o do plasma, mas não foi possível diferenciar as doenças neurológicas pelos níveis de RNA do HIV-1 do LCR.

[Neurologic disease due to adenovirus infection]. / Enfermedad neurologica por adenovirus.

The aim of this study was to assess the prevalence of adenovirusm (ADV) infections in neurological disorders. A total of 108 cerebrospinal fluid (CSF) samples from 79 encephalitis cases, 7 meningitis and 22 other neurological diseases analysed in our laboratory between 2000 and 2002 were studied. Forty nine (47.4%) belonged to immunocompromised patients. Viral genome was detected using nested polymerase chain reaction (Nested-PCR) and ADV genotypes were identified using partial gene sequence analysis of hexon gene. Adenovirus were detected in 6 of 108 (5.5%) CSF samples tested. All of these were from encephalitis cases, 6/79, representing 7.6% of them. No statistically significant differences were observed (p > 0.05) between the immunocompromised and non immunocompromised patients with ADV infection of the central nervous system. Two ADV genotypes (B1 and C) were identified. In conclusion, our results describe the role of ADV in neurologic infections in Argentina. The results contribute to the knowledge of ADV epidemiology, specially in encephalitis.

Determination of the six major human herpesviruses in cerebrospinal fluid and blood specimens of children.

AIM: To detect and differentiate six major human herpesviruses in the cerebrospinal fluid (CSF) and blood of children by polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP). METHODS: We synthesized two pairs of primers in the well-conserved regions of the DNA polymerase gene in human herpesviruses. One pair was designed to amplify cytomegalovirus (CMV), Epstein-Barr virus (EBV), herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2), and the other pair to amplify varicella-zoster virus (VZV) and human herpesvirus 6 (HHV-6) by PCR. Virus species identification was achieved by restriction enzyme digestion with BamHI and BstUI. Ninety-eight CSF and 75 blood specimens were analysed by this technique. At the same time, all blood specimens were also examined by enzyme-linked immunosorbent assay (ELISA). RESULTS: Thirteen (13.3%) of 98 CSF specimens and 26 (34.7%) of 75 blood specimens were positive for herpesvirus DNA in this PCR assay. Only 10 (13.3%) of the blood specimens were positive in ELISA for virus-IgM antibody. Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of PCR in detecting herpesvirus infections compared with ELISA were 100% (10/10), 75.4% (49/65), 38.5% (10/26) and 100% (49/49), respectively. These results indicate that the positive rate of PCR was significantly higher than that of ELISA (p < 0.05). The herpesvirus type of these positive specimens was rapidly detected using restriction enzyme digestion with BamHI and BstUI. CONCLUSIONS: PCR-RFLP is a specific, sensitive and accurate technique for the identification of herpesvirus infections in the CSF and blood of children.

Evaluation of a commercially available reverse transcription-PCR enzyme immunoassay (Enterovirus Consensus kit) for the diagnosis of enterovirus central nervous system infections.

A commercial reverse transcription (RT)-PCR amplification method was compared with culture for the diagnosis of enterovirus meningitis. In total, 99 cerebrospinal fluid (CSF) specimens were examined with the Enterovirus Consensus kit and shell vial culture. RT-PCR allowed the amplification of enterovirus cDNA and its detection in a microtitre plate by hybridisation. Clinical information and CSF analysis were used to resolve the discrepancy in results. The detection limit of the RT-PCR assay was determined with the Third European Union Concerted Action Enterovirus Proficiency Panel. There were 34 true-positive CSF specimens. Of these, RT-PCR detected 33 (sensitivity 97%), while culture detected 19 (sensitivity 54.5%). RT-PCR failed to detect one culture-positive specimen that contained inhibitors. When samples from the Third European Union Concerted Action Enterovirus Proficiency Panel were tested, the RT-PCR method gave identical results to those expected. The Enterovirus Consensus kit was rapid and statistically more sensitive than culture (p < 0.01) for the detection of enteroviruses in CSF, and may offer considerable benefits in the clinical management of patients with enterovirus meningitis.

Factors influencing PCR detection of viruses in cerebrospinal fluid of patients with suspected CNS infections.

BACKGROUND: Polymerase chain reaction (PCR) is used to detect viruses in the cerebrospinal fluid (CSF) of patients with neurological disease. However, data to assist its use or interpretation are limited. OBJECTIVE: We investigated factors possibly influencing viral detection in CSF by PCR, which will also help clinicians interpret positive and negative results. METHODS: CSF from patients with was tested for human herpesviruses types 1-6, JC virus, enteroviruses, and Toxoplasma gondii. The likelihood of central nervous system (CNS) infection was classified as likely, possible, or unlikely. PCR findings in these categories were compared using single variable and logistic regression analysis. RESULTS: Of 787 samples tested, 97 (12%) were PCR positive for one or more viruses. Of episodes likely to be CNS viral infections, 30% were PCR positive compared to 5% categorised as unlikely. The most frequent positive findings were Epstein Barr virus (EBV), enteroviruses, and herpes simplex virus (HSV). Enteroviruses and HSV were found predominantly in the likely CNS viral infection group, whereas EBV was found mainly in the unlikely group. Positive PCR results were more likely when there were 3-14 days between symptom onset and lumbar puncture, and when CSF white cell count was abnormal, although a normal CSF did not exclude a viral infection. CONCLUSIONS: The diagnostic yield of PCR can be maximised by using sensitive assays to detect a range of pathogens in appropriately timed CSF samples. PCR results, in particular EBV, should be interpreted cautiously when symptoms cannot readily be attributed to the virus detected.

Diagnosis of herpesvirus infections of the central nervous system.

The International Herpes Management Forum (IHMF) has produced guidelines to promote improved diagnosis of herpesvirus infections of the central nervous system (CNS). Recommendations include using polymerase chain reaction (PCR) analysis of cerebrospinal fluid (CSF) to help diagnose herpes simplex virus (HSV), varicella zoster virus (VZV) and cytomegalovirus (CMV) infections of the CNS. Laboratories routinely using such tests should participate in a proficiency testing programme. For retrospective diagnosis of herpesvirus infections of the CNS, intrathecal antibody detection can be used as an adjunct to PCR, assuming all appropriate controls are utilized. For suspected cases of herpes simplex encephalitis (HSE), a sensitive HSV PCR test of the CSF should be used in preference to other methods. Cultures are not recommended for HSE except as an adjunctive test in suspected neonatal HSV infections. While research continues into the role of PCR with VZV infections of the CNS, studies demonstrate that the technique is useful for diagnosing varicella-associated CNS syndromes but further research is required for its role in zoster-associated syndromes. For CMV CNS infections, PCR represents the most sensitive diagnostic method and can be used in conjunction with virus culture to determine suspected cases of CMV myelitis. For CNS infections with lymphotropic herpesviruses, a positive PCR test is suggestive, but not definitive, evidence of virus encephalitis. PCR analysis of CSF for Epstein-Barr virus can be useful for diagnosing AIDS-associated primary CNS lymphoma. This article presents the current evidence for these and other guidelines for the diagnosis of herpesvirus infections of the CNS.