Serum matrix metalloproteinase-9 (MMP-9) as a biomarker in paediatric and adult tick-borne encephalitis patients

Matrix metalloproteinases (MMPs) play an important role in central nervous system infections. We analysed the levels of 8 different MMPs in the cerebrospinal fluid (CSF) of 89 adult patients infected with tick-borne encephalitis (TBE) virus and compared them with the levels in a control group. MMP-9 was the only MMP that showed significantly increased CSF levels in TBE patients. Serum MMP-9 levels were subsequently measured in 101 adult TBE patients at various time points during the neurological phase of TBE and at follow-up. In addition, serum MMP-9 was analysed in 37 paediatric TBE patients. Compared with control levels, both paediatric and adult TBE patients had significantly elevated serum MMP-9 levels. In most adult patients, serum MMP-9 levels peaked at hospital admission, with higher serum MMP-9 levels observed in patients with encephalitis than in patients with meningitis. Elevated serum MMP-9 levels were observed throughout hospitalisation but decreased to normal levels at follow-up. Serum MMP-9 levels correlated with clinical course, especially in patients heterozygous for the single-nucleotide polymorphism rs17576 (A/G; Gln279Arg) in the MMP9 gene. The results highlight the importance of MMP-9 in the pathogenesis of TBE and suggest that serum MMP-9 may serve as a promising bioindicator of TBE in both paediatric and adult TBE patients.

Selected Biomarkers of Tick-Borne Encephalitis: A Review

Tick-borne encephalitis (TBE) is an acute disease caused by the tick-borne encephalitis virus. Due to the viral nature of the condition, there is no effective causal treatment for full-blown disease. Current and nonspecific TBE treatments only relieve symptoms. Unfortunately, the first phase of TBE is characterized by flu-like symptoms, making diagnosis difficult during this period. The second phase is referred to as the neurological phase as it involves structures in the central nervous system-most commonly the meninges and, in more severe cases, the brain and the spinal cord. Therefore, it is important that early markers of TBE that will guide clinical decision-making and the choice of treatment are established. In this review, we performed an extensive search of literature reports relevant to biomarkers associated with TBE using the MEDLINE/PubMed database. We observed that apart from routinely determined specific immunoglobulins, free light chains may also be useful in the evaluation of intrathecal synthesis in the central nervous system (CNS) during TBEV infection. Moreover, selected metalloproteinases, chemokines, or cytokines appear to play an important role in the pathogenesis of TBE as a consequence of inflammatory reactions and recruitment of white blood cells into the CNS. Furthermore, we reported promising findings on tau protein or Toll-like receptors. It was also observed that some people may be predisposed to TBE. Therefore, to understand the role of selected tick-borne encephalitis biomarkers, we categorized these factors and discussed their potential application in the diagnosis, prognosis, monitoring, or management of TBE.

The increased intrathecal expression of the monocyte-attracting chemokines CCL7 and CXCL12 in tick-borne encephalitis

Tick-borne encephalitis (TBE) is a relatively severe and clinically variable central nervous system (CNS) disease with a significant contribution of a secondary immunopathology. Monocytes/macrophages play an important role in the CNS inflammation, but their pathogenetic role and migration mechanisms in flavivirus encephalitis in humans are not well known. We have retrospectively analyzed blood and cerebrospinal fluid (CSF) monocyte counts in 240 patients with TBE presenting as meningitis (n = 110), meningoencephalitis (n = 114), or meningoencephalomyelitis (n = 16), searching for associations with other laboratory parameters, clinical presentation, and severity. We have measured concentrations of selected monocytes-attracting chemokines (CCL7, CXCL12, CCL20) in serum and CSF of the prospectively recruited patients with TBE (n = 15), with non-TBE aseptic meningitis (n = 6) and in non-infected controls (n = 8). The data were analyzed with non-parametric tests, p < 0.05 considered significant. Monocyte CSF count correlated with other CSF inflammatory parameters, but not with the peripheral monocytosis, consistent with an active recruitment into CNS. The monocyte count did not correlate with a clinical presentation. The median CSF concentration of CCL7 and CXCL12 was increased in TBE, and that of CCL7 was higher in TBE than in non-TBE meningitis. The comparison of serum and CSF concentrations pointed to the intrathecal synthesis of CCL7 and CXCL12, but with no evident concentration gradients toward CSF. In conclusion, the monocytes are recruited into the intrathecal compartment in concert with other leukocyte populations in TBE. CCL7 and CXCL12 have been found upregulated intrathecally but are not likely to be the main monocyte chemoattractants.

Increased concentration of interferon lambda-3, interferon beta and interleukin-10 in the cerebrospinal fluid of patients with tick-borne encephalitis

Tick-borne encephalitis (TBE) has a wide clinical spectrum, from asymptomatic to severe encephalitis, and host-dependent factors determining the outcome remain elusive. We have measured concentrations of pro-inflammatory/Th1 interferon-γ (IFNγ), immunomodulatory/Th2 interleukin-10 (IL-10), anti-viral type I (IFNβ) and type III (IFNλ3) interferons in cerebrospinal fluid (csf) and serum of 18 TBE patients, simultaneously genotyped for polymorphisms associated with the expression of genes IFNL3 (coding IFNλ3), IL10, CD209 and CCR5. IL-10, IFNβ and IFNλ3 were up-regulated in csf, with IFNλ3 level higher in patients with the milder clinical presentation (meningitis) than in meningoencephalitis. There was an increased serum IFNβ and a tendency for increased serum IL-10 in meningitis patients. Genotype in rs12979860 locus upstream of IFNL3 was associated with IFNλ3 expression and in rs287886 (CD209) - IL-10 expression. IL-10, IFNβ and IFNλ3 are expressed and play a protective role in TBE and their expression in TBE patients is associated with genetic polymorphisms.

[Serological confirmation of the prevalence of tick-borne encephalitis virus among patients with neurological infections in the Warmia-Masuria province in 2006-2010]

The aim of the study was to analyze of tick-borne encephalitis (TBE) in the Warmia-Masuria province on the basis of serological testing of 878 patients with symptoms of neurological infections, diagnosed in 2006-2010 in the Voivodeship Sanitary-Epidemiological Station in Olsztyn. Specific IgM and IgG antibodies against the TBE virus were detected in serum and cerebrospinal fluid samples by ELISA method. Percentage of persons with serologically confirmed TBE was 15.5%. This confirms contact with TBE virus and its role as the suspected cause of neurological infections in patients in the Warmia-Masuria province. Men and people over 46 years of age were more commonly seropositive. Among examined patients the percentage of seropositive men was 18.1% and the proportion of seropositive women was - 12.9%. Most positive results were found in patients between 46 and 50 years of age (20.7%) and in those aged 56-60 years (19.5%). Seasonal patterns were detected, with highest proportion of seropositive results in July, August and October.

[Serum and cerebrospinal fluid concentration of vitamins A, E and C in patients with tick-borne encephalitis]

We included in our study 18 patients hospitalized because of tick borne encephalitis (tbc) at the Departament of Infectious Diseases and Neuroinfections of Medical University of Bialystok. In this group, concentration of vitamins A, E and C in serum and cerebrospinal fluid (CSF) was measured before and after treatment. The control group consisted of 11 patients with no inflammatory changes in CSF were observed. We did not observe significant differences in concentration of vitamins in serum and CSF before and after treatment comparing to controls. However, we showed significant increase in concentration of vitamin E before and after treatment in both serum and CSF in patients with tbc in comparison with control group.

[Cilliary neurotrophic factor in tick-borne encephalitis]

THE PURPOSE OF THIS STUDY

To evaluate concentrations of cilliary neutrophic factor (CNTF) in serum and cerebrospinal fluid of patients with tick-borne encephalitis (TBE) and bacterial meningitis.

MATERIAL AND METHODS

49 patients (14 females and 35 males), aged 19 to 62 were examined. Patients were divided into three groups: group I--23 patients (47%) with diagnosed TBE, group II--16 patients (33%) with bacterial meningitis and 10 (20%) healthy individuals as control group. The examination was performed twice before and after 4-weeks treatment. In achieved results CNTF concentration in serum from group I and II in both examinations was significantly higher compared to control group.

RESULTS

Patients with TBE showed higher serum CNTF concentration compared to group with bacterial meningitis in both examinations as well. In examination 1 cerebrospinal fluid CNTF concentration of both groups was significantly higher in comparison to control group. Examined cytokine CSF concentration was higher in group with bacterial meningitis. After treatment CNTF concentration decreased significantly in group I and II. In group I CNTF concentration was comparable to control group.

CONCLUSION

Concentration of CNTF in csf could be used as a marker of the inflammatory process in the central nervous system.

Tick-borne encephalitis in Slovenia from 2000 to 2004: comparison of the course in adult and elderly patients

OBJECTIVE

To present epidemiological data and clinical characteristics of tick-borne encephalitis (TBE) in adult patients, and to compare findings in the subgroup over the age of 60 years with those aged 60 or under.

METHODS

The information for this retrospective study was obtained by review of medical documentation. All patients over 15 years of age hospitalized at the Department of Infectious Diseases, University Medical Center Ljubljana, Slovenia, between 2000 and 2004 with pleocytosis (cerebrospinal fluid leukocyte count >5 x 10(6) cells/l) and the presence of serum IgM antibodies against TBE virus qualified for inclusion in this report. Patients were divided into two groups according to their age (patients over the age of 60 were classified as seniors and those aged 60 or under as adults); the findings in the two groups were compared.

RESULTS

Of 448 patients with TBE, 318 were in the adult group and 130 in the senior group. Males predominated in both groups. A biphasic course of the illness was reported by 56% of patients. There were no significant differences in the majority of clinical parameters in the initial phase of TBE but several distinctions between adults and seniors were found in the second phase of the illness. Adults more often presented with fever, headache, stiff neck and photophobia, whereas seniors more frequently reported fatigue, altered consciousness and decreased muscle strength, these differences indicating a more classic course of TBE in the younger group and a somehow different and more severe acute disease in the older group. More severe acute disease and less favorable outcome in seniors was further corroborated by the occurrence of urine retention (18/318, 5.7% versus 27/130, 20.8%; P < 0.001), frequency of pareses (10/318, 3.1% versus 7/130, 5.4%; P = 0.002) and the need for antiedematous treatment (103/318, 32.4% versus 61/130, 46.9%; P = 0.005), as well as by the duration of treatment, duration of hospital stay and the death rate (0/318 versus 3/130, 2.3%; P = 0.024). Several distinctions were present also in laboratory findings, including higher cerebrospinal fluid leukocyte count in the adults than in the seniors (107 x 10(6) cells/l versus 47 x 10(6) cells/l; P < 0.001).

CONCLUSION

Direct comparison of the course and outcome of TBE revealed several distinctions between patients over 60 years of age and those aged 60 or under and corroborates previous assumptions that TBE is a more serious illness in the elderly population.

Chemokines CXCL10 and CXCL11 in the cerebrospinal fluid of patients with tick-borne encephalitis

OBJECTIVES

The aim of our study was to determine whether cerebrospinal fluid (CSF) of patients with tick-borne encephalitis (TBE) contains CXCL10, CXCL11, p40 subunit of interleukin-12 (IL-12)/IL-23, IL-18 and IL-15. We compared serum and CSF concentrations of CXCL10 and analysed the possible concentration gradient of this chemokine between the periphery and central nervous system.

MATERIALS AND METHODS

The study enrolled 19 TBE patients and 10 patients with non-inflammatory neurological diseases.

RESULTS

CSF of TBE patients contained CXCL10 (median 217 pg/ml), CXCL11 (8.3 pg/ml), p40 subunit of IL-12/IL-23 (38.9 pg/ml), IL-18 (30.1 pg/ml) and IL-15 (5.9 pg/ml). CXCL10 in the CSF of TBE patients was higher compared with serum (median 62 pg/ml, P < 0.001).

CONCLUSION

CSF of TBE patients contains CXCL10, CXCL11, p40 subunit of IL-12/IL-23, IL-18 and IL-15. Increased CXCL10 concentration in CSF suggests a role for this chemokine in the recruitment of CXCR3-expressing T-cells into the CSF of TBE patients.

[Concentration of interleukin 6 and 10 in tick-borne and purulend encephalomeningitis]

The aim of the study was to evaluate concentrations of interleukin 6 (IL-6) and interleukin (IL-10) in serum and cerebrospinal fluid (csf) of patients with tick-borne encephalitis (tbe) and purulent meningitis before and after 4 weeks of treatment.

MATERIAL AND METHODS

Group I consisted of 23 patients with tbe and group II - 16 patients with bacterial meningitis. Group III (control) consisted of 10 healthy men.

RESULTS AND CONCLUSIONS

In patients with tbe and purulent meningitis concentrations of IL-6 and IL-10 in serum and csf were initially increased and tended to remain increased after 4 weeks of treatment. It suggests significant role of IL-6 and IL-10 in inflammatory process within cns. Higher concentrations of IL-6 than IL-10 in csf than in serum suggests their local synthesis within cns and tendency to the limitation of the inflammatory response to the intratecal compartment. Concentrations of both IL-6 and IL-10 in csf and serum remained sgnificantly higher in patints with purulent meningits than in tbe, both before and after treatment. This observation may be helpful in diagnosing the ethiology of meningitis and meningoencephalitis and monitoring the course of the disease.

[Concentration of the beta-chemokine CCL5 (RANTES) in cerebrospinal fluid in patients with tick-borne encephalitis]

BACKGROUND AND PURPOSE

In tick-borne encephalitis (TBE), perivascular infiltrates are formed within the central nervous system (CNS) and are accompanied by pleocytosis with a predominance of T CD4+ lymphocytes in cerebrospinal fluid (CSF). Factors responsible for leukocyte flow into CNS in TBE have not been investigated. We evaluated the concentration of the chemotactic factor for lymphocytes, chemokine CCL5 (RANTES, Regulated upon Activation, Normal T cell Expressed and Secreted) in CSF and serum of patients with TBE and assessed its correlation with CSF pleocytosis.

MATERIAL AND METHODS

Group I consisted of 10 patients with TBE virus infection presenting as meningitis; group II included 11 patients with TBE presenting as encephalomeningitis or myeloencephalomeningitis. The control group consisted of 8 patients, in whom neuroinfection and infection with TBE virus was excluded. The concentration of CCL5 was measured by ELISA in CSF and serum samples taken within 24 hours after hospitalization (examination 1) and in the convalescence period, on average after 16 days (examination 2).

RESULTS

Mean CCL5 concentration in serum did not differ between the groups, while in CSF it was significantly increased in group I (64.3+/-75.5 pg/ml in examination 1 and 44.4+/-39.5 pg/ml in examination 2) and in group II (38.4+/-17.0 pg/ml in examination 1 and 48.8+/-24.7 pg/ml in examination 2) in comparison with controls (3.7+/-5.3 pg/ml). There was no significant difference regarding CCL5 concentration between groups I and II and between the examination 1 and 2. There was no correlation between the concentration of CCL5 and CSF parameters.

CONCLUSIONS

The concentration of CCL5 is increased in CSF, but not in serum of patients with TBE. This increase does not depend on the clinical form of the disease and is sustained after the disappearance of the symptoms of acute infection. Further studies are necessary to determine the source of CCL5, and its role in the pathogenesis of TBE and its sequelae.

[Intercellular adhesion molecules sICAM-1, sICAM-2, sICAM-3 and IFNgamma in neuroborreliosis and tick-borne encephalitis]

OBJECTIVE

The aim of this study was to evaluate the serum and CSF concentration of soluble intercellular adhesion molecules sICAM-1, sICAM-2, sICAM-3 and proinflammatory cytokine IFNgamma in patients with tick-borne encephalitis (TBE) and neuroborreliosis.

METHODS

The study group consisted of 40: 20 with TBE meningitis and 20 with Lyme meningitis. The serum and CSF levels of adhesion molecules and IFNgamma were determined by ELISA assay twice: before and after treatment.

RESULTS

Before treatment the concentrations of adhesion molecules and IFNgamma in serum as well as in CSF were significantly higher in both studied groups than in control group (with the exception of the serum level of sICAM-2 in TBE group). After the treatment, the serum parameters in TBE group decreased to the control level. CSF levels were also reduced, but still remained higher than in the control group. In patients with neuroborreliosis serum concentration of sICAM-1 and sICAM-2 did not change as compared with its level before treatment but other studied parameters in serum and CSF decreased significantly.

CONCLUSIONS

The results of our study confirm the participation of intercellular adhesion molecules in the pathogenesis of viral (TBE) and bacterial (neuroborreliosis) neuroinfections.

Elevated concentration of the chemokine CCL3 (MIP-1alpha) in cerebrospinal fluid and serum of patients with tick borne encephalitis

PURPOSE

Chemokines, including a chemoattractant for mononuclear cells CCL3 (MIP-1alpha), are responsible for attracting leukocytes into central nervous system (CNS) and cerebrospinal fluid (CSF) in meningitis and encephalomeningitis. We investigated the possibility of the involvement of CCL3 in tickborne encephalitis (TBE) pathogenesis.

MATERIAL AND METHODS

We studied 26 patients with TBE; 13 with meningitis (group I) and 13 with encephalomeningits (group II). Control group included 11 patients without infectious disease of the CNS. CCL3 concentration was measured by ELISA in serum and CSF on admission (examination 1) and after 2 weeks (examination 2) in TBE patients and once in controls.

RESULTS

In all control samples CCL3 concentration was below detection limit. In TBE, CCL3 serum concentration was: in group I--10.1 +/- 4.1 (mean +/- SD, ng/ml) in examination 1 and 12.4 +/- 4.8 in examination 2, and in group II--12.5 +/- 3.9 and 13.5 +/- 4.8, respectively. In CSF, CCL3 was detected: in group I in 5 patients in examination 1 (178 +/- 236 pg/ml) and 11 in examination 2 (457 +/- 215), in group II--in 8 (357 +/- 311) and 7 patients (326 +/- 330), respectively. There were no differences between group I and II. The comparison of CCL3 concentration gradient with albumin gradient between serum and CSF supported the possibility of intrathecal synthesis of CCL3.

CONCLUSIONS

1) Synthesis of CCL3, perhaps including intrathecal synthesis, is increased in TBE. 2) CCL3 concentration was much lower in CSF than in serum of the TBE patients, which argues against its significant role as chemoattractant in this condition.

[Evaluation of soluble platelet cell adhesion molecule sPECAM-1 and chemokine MCP-1 (CCL2) concentration in CSF of patients with tick-borne encephalitis]

Platelet-endothelial cell adhesion molecule-1 (PECAM-1) is a glycoprotein involved in the transendothelial migration of leukocytes and MCP-1 is a proinflammatory protein, member of the 1 subfamily of chemokines, acting as activator of specific leukocytes. The expression of PECAM-1 and MCP-1 was studied in various pathological processes, but very little is known about the significance of these molecules during inflammatory reaction in viral diseases of the nervous system, including tick-borne encephalitis.

MATERIAL AND METHODS

Cerebrospinal fluid was obtained from 17 patients with TBE, treated at the Department of Infection Diseases in Białystok. The level of sPECAM-1 and MCP-1 was evaluated by the ELISA method. The control group consisted of 18 patients in which the battery of tests, including CSF study, has excluded the organic character of the neurological syndrome. The U- Mann-Whitney test was applied to establish the statistical significance of the results.

RESULTS

The concentration of sPECAM-l and MCP-1 in cerebrospinal fluid of TBE patients was significantly increased in comparison with the. control group.

CONCLUSIONS

Elevated concentration of sPECAM-1 and MCP-1 may be a result of increased release from endothelical cells, activated T-cells, platelets and monocytes. Increased expression of sPECAM-1 is the significant but unspecific event in immunological processes in inflammatory reaction in TBE. The increased concentration of MCP-1 seems to be an essential event in the pathomechanism of inflammation in the central nervous system in TBE. It would be valuable in clinical conditions to search for the methods of inhibition of the increased expression of sPECAM-1 and MCP-1 in TBE to diminish the inflammatory reaction.

[Soluble CD40 and soluble CD40L concentrations in the serum and the cerebrospinal fluid of patients with tick borne encephalitis and neuroborreliosis]

BACKGROUND AND PURPOSE

The interaction between CD40 and CD40L is essential in generating of an immunological response also intrathecally. The aim of the study was estimation of a concentration soluble form of CD40, CD40L (CD154) in the bacterial and viral inflammation of the central nervous system in two compartments - blood circulation and intrathecally, before and after the treatment.

MATERIAL AND METHODS

sCD40 and sCD40L were tested twice before and after treatment in pairs serum and CSF of 40 patients treated in the Dept. of Infectious Diseases and Neuroinfections. Patients were divided in two groups: (n=20) patients with tick borne encephalitis (TBE) (group I, n=20) and patients with neuroborreliosis in the form of lymphocytic meningitis (group II, n=20). ELISA assays were performed.

RESULTS

Significantly increased concentrations of sCD40, sCD40L in CSF (higher in neuroborreliosis) were measured. We found also an increased concentration of sCD40L in inflammatory CSF in both tested groups (in neuroboreliosis lasting also after 4 weeks of treatment), compared with the control group (below the detection limit in normal CSF).

CONCLUSIONS

Results of estimation of the sCD40 and sCD40L concentrations indicate their role in the intrathecal inflammation process of bacterial and viral etiology. The increased serum concentration of sCD40L in TBE and CD40 in neuroborreliosis indicate that peripheral activation of the immunological system persists after cessation of treatment and after the clinical recovery. The defense mechanisms are more pronounced in neuroborreliosis than in tick borne encephalitis.

Ein Fall einer autochthonen Frühsommermeningoenzephalitis (FSME) in Mecklenburg-Vorpommern

HISTORY

A 61-year-old man was bitten by a tick at Lake Woblitz, near the town of Neustrelitz in former East Germany. Nine days later he saw his general practitioner because of fever and headache. Three weeks after the tick bite he was hospitalized with fever (39.2 degrees C) and mental confusion. Because he had taken a Nile cruise six months earlier, malaria was considered and he was transferred to the department of tropical medicine and infectious diseases of the University of Rostock.

INVESTIGATIONS

The patient was somnolent, his speech was slurred, and he had amnesic aphasia, as well as impaired fine motor control, but no meningism, focal signs, pyramidal tract or sensory impairment. Cerebrospinal fluid (CSF) showed mild lymphocytosis (9,400 leukocytes per microL; 89% lymphocytes) and elevated protein concentration (1322 mg/L) with blood brain barrier impairment and intrathecal IgM synthesis. Anti-tick-bite encephalitis (TBE) antibodies (ELISA: IgG and IgM) were present in serum and CSF, and serum immunofluorescence showed an eight-fold titer increase within two weeks. These findings confirm the diagnosis of TBE. Other infections (including those with cross-reacting flaviviruses) were excluded by appropriate antibody testing.

THERAPY AND CLINICAL COURSE

There is no specific antiviral treatment for TBE, but on symptomatic therapy the patient recovered fully within four weeks.

CONCLUSION

The site of the patient's infection is located 10 km to the west of an old TBE focus, but no TBE virus had been detected there after 1975. The case demonstrates that TBE should be included in the differential diagnosis of meningoencephalitis, even if the patient has not been in an acknowledged TBE endemic area.

[Serum and cerebrospinal concentrations of sICAM-1 sICAM-2, sICAM-3 in neuroborrellosis and tick borne encephalitis--preliminary report]

OBJECTIVE

The aim was to evaluate the concentrations of the soluble forms of ICAM-1, ICAM-2, ICAM-3 in the serum and cerebrospinal fluid (CSF) of patients with neuroborreliosis and thick borne encephalitis before and after therapy in comparison with the control group.

MATERIAL AND METHODS

We examined 30 patients, 10 in each group: neuroborreliosis-group I (NB), tick borne encephalitis--group II (TBE) and in the control group (group K). The diagnosis of neuroborreliosis and TBE based on the clinical features was confirmed by ELISA assays: FSME Virus/TBE Virus test (VIRION, Germany) for TBE and Borrelia IgM and IgG Recombinant (Biomedica Austria) for NB. The assays of sICAM-1, sICAM-2, sICAM-3 (ELISA, Bender Med System, USA) were performed twice in group I and II: before and after 3-4 weeks long treatment and once in control group.

RESULTS AND CONCLUSIONS

Increased concentration of soluble forms of ICAM-1, ICAM-2, ICAM-3 in CSF suggest their important role in inflammatory process of viral and bacterial origin. In NB group, the serum concentrations of sICAM-1, sICAM-2 were significantly increased before and after treatment in comparison with control as well as with the analogous test results in TBE group. It may suggest NB as the part of systemic inflammation. The CSF concentration of sICAM-2 decreases after treatment in NB group in comparison with the analogous test results of TBE group. The increased CSF concentration of sICAM-2 in TBE group when compared to the CSF concentration in NB group suggest slow recovery and still persisting immunological activation in this group, even when the neurological symptoms disappeared. Increased concentrations in CSF in both diseases indicate intrameningeal activity of lymphocytes and may be a useful marker of inflammation.

[Interferon gamma concentration in the cerebrospinal fluid of patients with tick-borne encephalitis]

BACKGROUND AND PURPOSE

The purpose of this work was to evaluate interferon gamma (IFN-g) concentration in the cerebrospinal fluid of patients with diagnosed tick-borne encephalitis (TBE) early in the course of the disease and after the treatment.

MATERIAL AND METHODS

The cerebrospinal fluid of 40 patients with TBE was examined. Patients were divided into 4 groups: group 1 consisted of 13 patients with mild clinical course, group 2 included 12 patients with prolonged TBE showing the presence of inflammatory markers after the treatment, group 3 comprised 9 patients with severe TBE presenting with disorders of consciousness and group 4 consisted of 6 patients with a simultaneous B. burgdorferi infection. The cerebrospinal fluid was examined twice--during TBE diagnosing and after the treatment. IFN-g was detected by the ELISA method.

RESULTS

The concentration of IFN-g in the cerebrospinal fluid in the first examination was significantly higher in all four groups of patients in comparison with controls. After the treatment, concentration of IFN-g decreased significantly in all studied groups. The highest concentration of IFN-g at the first examination was found in group 3. The concentration of IFN-g at the second examination was similar among 4 groups of patients and in controls.

CONCLUSIONS

We found the correlation between IFN-g concentration in the cerebrospinal fluid of patients at the early stage of TBE and inflammation activity. We did not find any association between IFN-g concentration and a persistent increase of the cerebrospinal fluid parameters.

Development of a quantitative real-time RT-PCR assay with internal control for the laboratory detection of tick borne encephalitis virus (TBEV) RNA

BACKGROUND

Tick borne encephalitis virus (TBEV), is a human flavivirus causing tick borne encephalitis (TBE), a viral infection of the central nervous system endemic in Europe and Asia.

OBJECTIVES

To develop a reverse transcription polymerase chain reaction (RT-PCR) assay based on quantitative real-time RT-PCR technology (TaqMan) for detection and quantification of TBEV RNA. The test includes an internal control (IC) to avoid false negative results.

STUDY DESIGN

The system was established and validated using wild-type (WT) non-infectious synthetic RNA representing a fragment of the 3' non-coding region of the TBEV genome. In addition, synthetic RNA differing from the WT synthetic RNA by a unique probe binding region was used as IC to monitor the overall efficiency of the RT-PCR.

RESULTS

The analytical sensitivity of the assay was at least ten copies of the TBEV synthetic transcript in presence of 50 copies of the IC. Successful amplification was obtained for different strains within the TBEV complex (Hypr, Hochosterwitz, Laibach, Elsass=Alsace, ZZ9, Wladiwostok). Among 14 serum and 21 cerebrospinal fluid (CSF) samples obtained from 28 patients with clinical suspicion of TBEV 1 CSF sample tested positive for TBEV RNA. In addition, no TBEV RNA could be detected in blood samples obtained from three vaccinated people 1 and 3 days post-vaccination. Thus indicating that a positive result is unlikely to be caused by recent vaccination.

CONCLUSIONS

A quantitative, highly sensitive and specific real-time RT-PCR assay has been developed for the detection of TBEV RNA. Inclusion of an IC is important to monitor the possible occurrence of false-negative results caused by the presence of inhibitory factors. This assay should be an important asset for the routine laboratory detection of TBEV RNA.

[Lactoferrin and its role in the pathogenesis of tick-borne encephalitis]

The content of lactoferrin (LF) was studied in the liquor and blood of patients with tick-borne encephalitis (TBE) of the meningeal and focal types; additionally, the information density of the discussed parameter was assessed for evaluating the severity and degree of the inflammation process in the central nervous system (CNS). The LF level was determined in liquor of 37 samples obtained from TBE patients (main group) and of 10 persons with osteochondrosis (controls); it was also determined in the serum taken from 21 TBE patients and from 40 healthy donors by using the immune-enzyme analysis. The LF concentration in TBE patients was found to exceed the normal value by 1.5-3 times during the whole observation period. As for the liquor, it was high, by the onset of the disease, by more than 20 times, however, after the 7th day it was higher 6-fold. A direct dependence of a concentration of the studied protein on a form and severity of the disease was established. The LF level in the liquor of TBE patients alongside with clinical signs can be an objective indicator of a severity and activity of the inflammation process in the CNS; it can also be a criteria of how much the conducted therapy effective is.

Report of the Meningitis Program of the International Scientific Working Group on TBE. Serological screening of patients with viral CNS-infection of unknown etiology in search of undiagnosed TBE cases

The endemicity of tick-borne encephalitis (TBE) in Europe is changing. Potential undetected or emerging TBEV foci and the risk of underdiagnosis due to a low awareness among the medical community form the background of this retrospective multicenter follow-up study. We investigated the possibility of undiagnosed TBE cases among patients with presumed viral central nervous system (CNS)-infection of unknown etiology. Eight centers in four European countries provided sera and/or cerebrospinal fluid (CSF) samples from 233 individuals. The samples were screened with a commercial TBEV ELISA test system (IgM and IgG). Positive or borderline samples were re-evaluated at the Institute of Virology in Vienna by an in-house ELISA test and a neutralization test (NT). Two previously undiagnosed Swedish TBE patients were verified. Three additional individuals from Swedish centers were IgG ELISA and NT positive. No NT positive individuals were found from France, Belgium or The Netherlands. Nineteen individuals were found IgG TBE ELISA positive, but negative in NT, indicating unspecific reactivity. At least four of those patients were vaccinated against yellow fever. The probable reason for the reactivity seen in these individuals is the well-known cross-reactivity existing among flaviviruses.

Lymphocyte subset numbers in cerebrospinal fluid: comparison of tick-borne encephalitis and neuroborreliosis

OBJECTIVE

The aim of this study was to analyze lymphocyte subset numbers in cerebrospinal fluid (CSF) from patients with tick-borne encephalitis (TBE) and acute neuroborreliosis.

METHODS

CSF lymphocyte subsets were enumerated in 42 TBE and nine neuroborreliosis patients using flow cytometry.

RESULTS

The CSF numbers of CD4+, CD8+, HLA-DR+ and total-T lymphocytes, B lymphocytes, and NK cells were all greater in neuroborreliosis patients than in TBE patients. Neuroborreliosis patients showed positive correlation of CSF protein levels with the numbers of CD4+, HLA-DR+ and total-T lymphocytes. Also, the numbers of CSF B lymphocytes correlated positively with intrathecal Borrelia burgdorferi-specific IgG antibodies. Conversely, TBE patients demonstrated intrathecal protein levels that correlated positively with all investigated CSF lymphocyte subsets.

CONCLUSION

These results suggest an intensive recruitment of lymphocyte subsets into the central nervous system (CNS) during acute neuroborreliosis, whereas TBE is characterized by a lower accumulation of lymphocyte subsets in the CSF.

[Decreased antioxidant-defence mechanisms in cerebrospinal fluid (CSF) in patients with tick-borne encephalitis (TBE)]

14 patients with Tick-borne Encephalitis (TBE) aged 21-64 (mean = 42.3) were analysed. The activity of superoxide dismutase (SOD), glutathione reductase (GSSG-R), glutathione peroxidase (GSH-Px), concentrations of malondialdehyde (MDA) and total sulphydryl groups (-SH) were measured in cerebrospinal fluid (CSF). Control group consisted of 10 patients whose CSF parameters remained in normal range. The CSF examination was performed twice: before and 3 weeks after treatment. The analysed activity of SOD, GSH-Px, GSSG-R, MDA and total sulphydryl groups (-SH) during the acute stage of the disease was significantly lower comparing to the control group. Despite the treatment, GSSG-R activity, MDA concentration and total sulphydryl groups--SH further lowered significantly. Although the SOD activity in CSF was higher in the second examination, it remained significantly lower comparing to the control group. We showed that the GSH-Px and GSSG-R activity in CSF after the acute stage of the TBE remained significantly lower than in the control group. Our examinations prove that during the TBE an increased generation of oxygen-derived free radicals occurs what shows decreased activity of the antioxidant parameters (SOD, GSH-Px, GSSG-R) and decreased concentration of total sulphydryl groups--SH in CSF. Our results suggest that during TBE, molecular structures injury of enzymes and antioxidative reactive cofactors may occur.

Serum time course of two brain-specific proteins, alpha(1) brain globulin and neuron-specific enolase, in tick-born encephalitis and Lyme disease

METHODS

Time courses of the serum concentrations of two brain-specific proteins (BSP), alpha(1) brain globulin (alpha(1)BG, an astroglial marker) and neuron-specific enolase (NSE), were studied in patients with severe tick-born encephalitis (TBE) and Lyme disease (LD; neuroborreliosis). The concentrations were determined on the second day of the acute phase and then on the 7th, 12th, 18th, and 23rd days. Apparent rate constants for the elimination of the BSP from blood (k(e)) were calculated with the non-linear regression.

RESULTS

In patients with TBE, the highest serum concentrations of alpha(1)BG and NSE, observed on the second day, were followed by their monotonic decrease to the normal levels reached by the 23rd day. The mean k(e) values for alpha(1)BG and NSE were found to be significantly different (0.086+/-0.003 vs. 0.057+/-0.006 day(-1), respectively; p<0.05). Higher serum levels of both BSP were observed in the more severe clinical cases and in the cases with unfavorable outcomes. Similar profiles were also observed for the serum alpha(1)BG and NSE in LD.

CONCLUSIONS

These results suggest that, in the patients examined, the blood-brain barrier was partially impaired; the quantitative parameters of the serum BSP time courses can be indicative of the extents of the neuronal and/or glial lesions.

Predictive value of serum and cerebrospinal fluid procalcitonin levels for the diagnosis of bacterial meningitis

BACKGROUND

The value of serum and cerebrospinaL fluid (CSF) procalcitonin for differentiating between acute bacterial and viral meningitis was assessed and compared to other parameters which are usually used in clinical practice.

PATIENTS

45 adult patients (20 with bacterial and 25 with tick-borne encephalitis, TBE) were included in this prospective study.

RESULTS

The median serum procalcitonin Level in patients with bacterial meningitis was 6.45 ng/ml (range 0.25-43.76 ng/ml) and in the group with viral meningitis 0.27 ng/ml (range 0.05-0.44 ng/ml). 11 patients with bacterial meningitis had an elevated procalcitonin concentration not only in serum, but also in CSF. A serum procalcitonin Level > 0.5 ng/ml had a positive predictive value for bacterial meningitis of 100% and a negative predictive value of 93%, while corresponding values for CSF procalcitonin were 100% and 74%, respectively.

CONCLUSION

Serum and CSF procalcitonin concentrations > 0.5 ng/ml appear to be a reliable indicator of bacterial central nervous system (CNS) infection, with maximal positive predictive values and high negative predictive values.

[The possible role of alpha 2-macroglobulin in regulating the immune components of the brain in tick-borne encephalitis]

In tick-borne encephalitis certain immunopathological reactions develop in the tissues of the central nervous system; alpha 2-macroglobulin may serve as the marker of the activity of these reactions. The dynamic study of liquor taken from 16 patients with the meningeal and focal forms of tick-borne encephalitis (TBE), 8 patients with severe craniocerebral traumas accompanied by meningitis and 10 patients with osteochondrosis was made. As revealed in this study, in TBE patients the level of alpha 2-macroglobulin increases 3.5-fold and remains stable during the acute period of the disease.

Comparison of the epidemiological and clinical features of tick-borne encephalitis in children and adults

The aim of this prospective study was to compare epidemiological data and clinical features in children and adults with tick-borne encephalitis (TBE). Patients with aseptic meningitis diagnosed at the University Medical Centre, Department of Infectious Diseases, Ljubljana, Slovenia, from June to August 1997, in whom the diagnosis of TBE was ascertained by the presence of serum IgM antibodies against TBE virus, who were serologically negative for Borrelia burgdorferi sensu lato and had a negative PCR CSF result on enteroviral infection, were included in the study. Out of 213 patients with aseptic meningitis, 80 (37.56%) fulfilled inclusion criteria. There were 20 children and 60 adults. In both groups males predominated. Virtually all patients had headache and fever, and more than 50% suffered from vomiting. The majority of patients in both groups recalled a tick bite, had a biphasic course of the illness, and was found to have obviously expressed meningeal signs. In both groups the median CSF leukocyte count was somewhat lower than 100 x 10(6)/l with a predominance of lymphocytes. Children were more often given antibiotics during the initial phase of TBE than adults (p = 0.0095). Several other statistically significant distinctions (p < 0.05) were found including the frequency of fatigue, malaise, vertigo, photophobia, myalgias, arthralgias, as well as elevated CSF albumin and protein concentration, elevated albumin quotient and IgG quotient; all these findings were more often present in adults. In addition a longer duration of fever, more frequent need for anti-edematous treatment and longer hospitalization were found in adults. Direct comparison of clinical and epidemiological characteristics of TBE in children and adults revealed differences in several clinical and laboratory features and corroborates the previous conclusion that TBE in childhood is a milder illness than TBE in adults.

Laboratory findings in tick-borne encephalitis--correlation with clinical outcome

Infection with the tick-borne encephalitis virus (TBEV) can result in various neurological complications. At present, there are little data available on laboratory findings that might help predict the clinical course and prognosis of tick-borne encephalitis (TBE). In the present study 100 patients with TBE were examined in respect to various laboratory parameters potentially characteristic for the disease and indicative for the prognosis in TBE. Pleocytosis, impairment of the blood-CSF barrier and intrathecal synthesis of immunoglobulins (IgM > IgG, IgA) were common findings in most patients. On admission to the hospital, 84% of the patients presented with an intrathecal synthesis of TBEV-specific IgM and/or IgG antibodies in the CSF. At follow-up, intrathecal synthesis of TBEV-specific antibodies was demonstrated in all patients studied within 15 days after the first examination, but changes of CSF parameters did not correlate with the clinical course of disease. In contrast to those with moderate course of disease, patients with severe courses of TBE displayed higher cell counts in the CSF and lower concentrations of neutralizing antibodies in serum, and more frequently revealed an intrathecal synthesis of total IgG. TBE-specific oligoclonal IgG antibodies in the CSF were demonstrated only in three patients with prior, incomplete, vaccination against TBE. The severe course of disease in individual patients with TBE may result from a slow or low production of neutralizing antibodies. In these patients, the more intense damage of the CNS tissue is reflected by higher cell counts in the CSF. At onset of disease the presence of a low concentration of neutralizing antibodies in serum and a high cell count in the CSF might indicate an unfavorable course of TBE.

[Cerebrospinal fluid serotonin concentration in pyogenic and tick-borne encephalomeningitis]

Cerebrospinal fluid (CSF) serotonin was determined in 38 patients with pyogenic meningitis and tick-borne encephalitis (TBE) before and after treatment. Increase of CSF serotonin concentration was observed in acute phase of pyogenic meningits and normalized after treatment.

Prevalence of antibodies to tick-borne encephalitis virus and Borrelia burgdorferi sensu lato in samples from patients with abnormalities in the cerebrospinal fluid

Within the last few years, an increase in cases of tick-borne encephalitis (TBE) as well as an expansion of TBE-endemic regions have been noted in southern Germany. In 1994, a patient was diagnosed for the first time with TBE that had been acquired in Saarland. Up to this point, the Saarland had been considered TBE-free. In a retrospective study, we tested serum samples from 904 patients with abnormalities in the cerebrospinal fluid (CSF) for TBE antibodies. The IgG ELISA used (Immunozym-FSME-IgG, Immuno GmbH, Heidelberg, Germany) yielded 47 positive and 134 borderline sera. The percentage of positive sera showed a significant increase during the time period studied (1989-1994): One IgG-positive serum sample was also IgM-positive. Of the CSF samples, 2 were IgG-positive and 7 were borderline for IgG. In three patients, a positive intrathecal antibody index (IAI) was found, indicating an incrathecal antibody production. An analysis of the vaccination history of the patients showed that only 19% of the patients with a positive TBE IgG titre and only 5.9% of the borderline patients had been vaccinated against TBE. We compared 98 patients that tested positive or borderline for TBE IgG with 98 sex-and-age-matched patients that tested negative. The parameters studied included the patient's complaints upon discharge, the average duration of stationary treatment and 16 different neurological symptoms. We did not observe any significant differences between the two groups. We also tested the sera of 704 of the 904 patients for antibodies to Borrelia burgdorferi (Borrelia burgdorferi ELISA, Genzyme Virotech GmbH, Rüsselsheim, Germany). 155 (22.0%) of the sera were IgG-positive, 136 (19.3%) were borderline, 32 patients (4.6%) had a positive intrathecal antibody index (IAI). The fact that no patient with a clinically manifest case of TBE had acquired the disease in the Saarland indicates that the actual risk of acquiring an acute TBE in the Saarland is very low, despite the high percentage of samples that tested positive for IgG in the ELISA. The increase in the number of serum samples that tested positive for TBE IgG during the last years could be explained by an expansion of TBE regions into the Saarland, increasing vaccination of the population or more travel to endemic regions. The proportion of patients with IgG antibodies to Borrelia was 22%. Because only part of the patients suffered from an acute, clinically manifest borreliosis, and since the serum IgG titre had remained positive for many years after contact with the microorganisms, we suspected that a large percentage of the population would show signs of a clinically silent infection in their sera. 4.6% of the patients had a positive IAI quotient, a clear indication of neuroborreliosis.

[Concentrations of tumor necrosis factor alpha and interleukin-1 beta in cerebrospinal fluid in the course of tick-borne encephalitis]

CSF concentrations of TNF-alpha and Il-1 beta were detected in patients with TBE. The cytokines were detected by immunometric assay by MEDGENIX kit. CSF Concentrations of TNF-alpha and IL-1 beta in patients with TBE were significantly higher than in control group before as well as after treatment and normalization of CSF parameters. These concentrations were lower comparing to one obtained in group of bacterial meningitis. There was no correlation between concentration of cytokines and other CSF parameters (cytosis, protein, glucose concentration). Concentrations of analysed cytokines did not change significantly before and after treatment. Detection of CSF concentrations of TNF-alpha and Il-1 beta in patients with tick-borne encephalitis can be used to evaluate efficacy of treatment and retreat of infection.

Cytologic and immunoenzymatic findings in CSF from patients with tick-borne encephalitis

OBJECTIVE

To evaluate the dynamics of cytologic changes in the cerebrospinal fluid (CSF) of patients with tick-borne encephalitis (TBE) and to determine the various forms of mononuclear cells by immunocytochemical methods.

STUDY DESIGN

To perform a cytologic analysis of 200 cells in stained sediment of CSF. To determine the population and subpopulation of mononuclear cells by using monoclonal antibodies.

RESULTS

Pleocytosis in CSF in patients with TBE during the first three days of illness was, on average, 570 cells per cubic millimeter with about 60% neutrophils. Mononuclear cells predominated from the fifth day of illness. Among lymphoid cells, 18% carried marker CD20 and 60% of them marker CD3. Among monocytoid cells, 66% carried marker CD32.

CONCLUSION

CSF cytology findings reflect the immunologic and inflammatory changes in the CNS during TBE.

Clinical value of specific intrathecal production of antibodies

The production of intrathecal antibodies is considered a highly specific marker for an infection of the central nervous system (CNS), e.g. borreliosis or tick-borne encephalitis (TBE). To investigate the validity of this assumption, we examined records of patients who had been hospitalized between 1989 and 1995, who were tested for borreliosis (n = 8003) and TBE (n = 904) and whose cerebrospinal fluid (CSF) had subsequently tested positive for intrathecal production of antibodies. The time period between the beginning of the symptoms and the time of the CSF examination ranged from one day to six weeks. Seventy-seven patients showed a production of intrathecal antibodies against Borrelia burgdorferi. Three of these patients were false positives with no history and no clinical signs of neuroborreliosis. In two cases, this was due to a non-specific cross-reaction caused by a preceding infection with syphilis. The third false positive was possibly caused by an earlier administration of immunoglobulins. Three patients showed a production of intrathecal antibodies against TBE virus. Two of these patients were false positives. In one case, we suspect that the production of intrathecal antibodies was caused by a non-specific immune reaction during an acute neuroborreliosis. One year earlier, the patient had contact with TBE virus through a vaccination against TBE. The cause of the second false positive is unclear, the clinical findings, acute encephalitis and the serological analysis suggest a cross-reaction with a virus similar to TBE. A specific intrathecal production of antibodies is not a proof for an infection of the CNS. In unclear cases, one should carry out a Western blot analysis or, if one suspects a case of TBE, a neutralization test.

Flow cytometric analysis of lymphocytes in cerebrospinal fluid in patients with tick-borne encephalitis

INTRODUCTION

Cerebrospinal fluid (CSF) lymphocyte subsets were examined by flow cytometry in 33 patients with tick-borne encephalitis (TBE) in order to determine their values.

PATIENTS AND METHODS

Lymphocytes were isolated from CSF and lymphocyte subsets were determined: lymphocytes T (CD3+), lymphocytes B (CD19+), NK cells (CD3-CD56+), helper T cells (CD3+CD4+) and cytotoxic T cells (CD3+CD8+). The expression of IL-2 receptors (CD25+) and transferrin receptors (CD71+) on T cells and HLA-DR molecules on T cell subsets was examined. Furthermore, possible relationships among different TBE patient population variables (gender, age, severity of disease, duration of meningitis) were considered.

RESULTS

The analyses of the CSF lymphocyte population subsets are presented. Lymphocytes T (CD3+) were significantly higher in the CSF than in the peripheral blood as was the case with the T cells that expressed transferrin receptors (CD71). Lymphocytes B (CD19+) and NK cells (CD3-CD56+) prevailed in the peripheral blood. In the early course of the disease, a higher expression of HLA-DR molecules on T lymphocytes was observed, while later a higher expression of IL-2 receptors (CD25+) was observed.

DISCUSSION

Significant differences in lymphocyte subsets between the CSF and the peripheral blood were found. Significant time-dependent changes of CSF lymphocyte subsets during course of infection were observed. The results of the present study give us deeper insight into CNS cellular immunopathogenic mechanisms in patients with TBE.

Tick-borne encephalitis complicated by a polio-like syndrome following a holiday in central Europe

We report a case of Central European tick-borne encephalitis (CETE) in a 54-year-old man, presenting with fever and neurological complications following a holiday in Austria. A disease resembling paralytic poliomyelitis may develop with upper and lower extremity paralysis, as is the case in our patient. Our patient was most likely infected by eating goat's cheese, made of unpasteurised goat's milk. The diagnosis was confirmed by a positive IgM antibody response to the virus in the serum.

Intrathecal production of neopterin and beta 2 microglobulin in tick-borne encephalitis (TBE) compared to meningoencephalitis of other etiology

To study the pathophysiology of tick-borne encephalitis (TBE), the kinetics of neopterin and beta 2 microglobulin (beta 2M) production were measured in sequential, cerebrospinal fluid (CSF) and serum samples in 133 patients with aseptic meningoencephalitis (TBE, n = 72; non-TBE, n = 61). Intrathecal production of neopterin was demonstrable in all patients. Neopterin levels in CSF were elevated already at day 2: geometric mean value in TBE 36 nmol/l (range 1-253), in the non-TBE group 29 nmol/l (0.2-96). At day 9 and week 6 the neopterin level was significantly higher in TBE (86 (19-725) and 17 (4-122) nmol/l) than in non-TBE (28 (5-109) and 3 (0.2-58) nmol/l) (p < 0.001). After 1 year CSF levels were within the normal range. The beta 2M response in CSF followed the pattern of neopterin. The intensity and duration of neopterin and beta 2M was not correlated to the clinical course. Neopterin seems to be a more sensitive indicator of intrathecal T-cell response and inflammatory reaction than beta 2M. The results indicate that a long-lasting strong inflammatory reaction is of pathophysiological significance in TBE.

Antibodies against tick-borne encephalitis virus (TBEV) non-structural and structural proteins in human sera and spinal fluid

Western immunoblotting of the serum and spinal fluid of patients with tick-borne encephalitis (TBE) revealed the presence of antibodies against non-structural and internal virion proteins. Antibodies against different viral proteins have been shown to appear 8 days postinfection and to circulate for more than 2 months in case of acute TBE. Antibodies against structural glycoprotein E and non-structural glycoprotein NS1 do not prevail over antibodies against other kinds of viral proteins. The large viral non-structural proteins NS5 and NS3 and small hydrophobic proteins NS2A and NS4B can cause an effective immune response as well. There is no strong correlation between immune response spectrum and fever or meningitis forms of disease. However, sera of patients with chronic TBE contained IgM antibodies to virus-specific proteins more than 1 year later and IgG antibodies with very low titers (if any).

Increased intrathecal synthesis of fibronectin in bacterial and carcinomatous meningitis

Immunoreactive fibronectin (Fn) was quantified in paired cerebrospinal fluid (CSF) and serum samples from patients with bacterial meningitis (n = 46), tick-borne encephalitis (TBE) (n = 6), HIV infection (n = 6), Guillain-Barré syndrome (n = 5), carcinomatous meningitis (n = 11), multiple sclerosis (n = 15), disk disease (n = 11), and controls (n = 28). A highly significant elevation of CSF Fn was found in bacterial meningitis, TBE, and carcinomatous meningitis. There were no significant differences in serum Fn between any of the groups. An Fn index to estimate the rate of intrathecal Fn synthesis reached the highest value in bacterial meningitis. Our findings suggest that CSF Fn may be an indicator of adequate host reaction and tissue repair. For diagnostic purposes, the determination of CSF Fn probably does not add much to routine CSF laboratory tests.

Agents of equine viral encephalomyelitis: correlation of serum and cerebrospinal fluid antibodies

A survey was conducted by testing 115 paired equine serum and cerebrospinal fluid samples by hemagglutination-inhibition for antibodies to Powassan and snowshoe hare viruses, and by virus neutralization for antibodies to equine herpesvirus type 1. Twenty-five samples were from horses with spontaneous neurological disease and the remainder from horses euthanized because of various nonneurological disorders. All sera and cerebrospinal fluids were negative for antibodies to Powassan virus. Fifty-one sera (44.3%) and 15 cerebrospinal fluids (13.0%) had antibodies to snowshoe hare virus. Ninety-eight sera (85.2%) and four cerebrospinal fluids (3.5%) were positive for antibodies to equine herpesvirus type 1. Powassan virus was inoculated intracerebrally into one, and intravenously into four ponies. Neurological signs associated with a nonsuppurative encephalomyelitis occurred in three ponies. Antibodies to Powassan virus were detected in sera of all animals but in cerebrospinal fluids of only two. Powassan virus was isolated from brain and spinal cord of only the intracerebrally inoculated animal.

Tick-borne encephalitis: a simple method for detection of antibody production in the brain

Antibodies found in c.s.f. of patients with TBE are usually produced in the CNS itself, although their presence might also be due to a leak in the blood brain barrier. In the case of local antibody production the ratio of the TBE specific IgM or IgG to the total immunoglobulin is relatively high in c.s.f., whereas in case of a leak this ratio is lower and corresponds to that of the serum. Local antibody production in the brain can therefore be assumed, if the ratio is higher in c.s.f. than in serum. It is possible to determine this ratio in an anti-mu or anti-gamma capturing antibody ELISA, provided that the concentration of capturing antibodies represents the limiting factor of the test system. Under these conditions the absorbance values obtained are a direct reflection of the TBE reactive to nonreactive antibody ratio, since they compet for the limited binding sites presented on the solid phase. Higher extinction values of c.s.f. compared to that of serum are therefore an indication for local antibody production in the brain. Using the method described, differences were found in the production of IgM and IgG antibodies against TBE in the CNS from patients with different clinical history.

Investigations on blood and cerebrospinal fluid lymphocytes in patients suffering from tick-borne encephalitis

This paper deals with the immuno-pathological characteristics of tick-borne encephalitis. With the appearance of neurological signs, there is a strong T cell reaction in th peripheral blood. The following seven days are characterized by the appearance of specific cell-mediated reaction in the peripheral blood; in the cell-mediated reaction in the peripheral blood; in the cerebrospinal fluid, an increasing number of B cells and specific antibodies can be detected. After a week, the percent positivity of cell-mediated immune reactions is higher and there is a T cell dominance in the cerebrospinal fluid. Intact cellular immunity against specific antigen is required for the management of this disease. There are major differences in the results obtained from patients suffering from meningitis alone and those suffering from meningoencephalitis.