[Diagnostic relevance of the chemokine CXCL13 and anti-C6 peptide antibodies in patients with neuroborreliosis]. / Diagnostický význam chemokinu CXCL13 a protilátek proti C6 peptidu u pacientu s neuroborreliózou.

AIM OF THE STUDY: The study was focused on testing the diagnostic value of detection of the chemokine CXCL13 (B lymphocyte chemoattractant) and anti-C6 peptide (synthetic peptide derived from B. burdorferi VlsE protein) antibodies in patients with neuroborreliosis (NB). MATERIAL AND METHODS: One hundred and twenty-nine patients with clinical suspicion of neuroinfection were included in the study. Eighty patients with NB (positive for antibodies in serum and CSF) were subdivided into four groups (A1-A4) based on positivity/negativity of the antibody index (AI) and pleocytosis. The control group was composed of 49 patients with a negative AI and absence of CSF pleocytosis. Chemokine CXCL13 and anti-C6 antibodies were examined by commercial kits (Human CXCL13/BLC/BCA-1 Immunoassay, R&D Systems, INC, USA and C6 B. burgdorferi (Lyme) ELISA, Immunetics Inc. USA). The CXCL13 cut-off values were set to 130 pg/ml for the CSF and 62 pg/ml for the serum. RESULTS: The highest CSF levels of CXCL13 chemokine were found in group A1 (pleocytosis, AI positive), and they were significantly higher (p < 0.001) comparing with other groups except A3 (pleocytosis, AI negative; p = 0.04). Group A3 also showed significantly higher levels of CXCL13 than groups A2 (without pleocytosis, AI positive; p = 0.005), A4 (without pleocytosis, AI negative), and B (p < 0.001). The differences in the serum CXCL13 levels between groups were non-significant. The serum anti-C6 antibodies were detected in all NB groups and the positivity rates did not differ between groups (92%) except for A3 where 55% of the patients were positive. In the CSF, the highest anti-C6 sensitivity was found in the patients with a positive AI (A1 88.6%; A2 76.9%) while in the groups with a negative AI, it was low (A3 25%; A4 0%). In group B, anti-C6 antibodies were not detected. CONCLUSION: The highest CSF CXCL13 levels were found in early stage NB. Elevated CXCL13 concentrations correlate better with pleocytosis than with AI positivity; however, there exist some patients with a positive AI who have low CXCL13 levels. These patients are most probably those in the late - subacute stage of neuroinfection. The CXCL13 testing seems to be the most diagnostically helpful in the acute stage of NB where AI is still negative. The clinical sensitivity of the C6 ELISA test appears to be insufficient for CSF examination under our conditions. On the contrary, the specificity of this test was proven high, because none of the controls tested positive.

Detection of antigen-specific T cells in patients with neuroborreliosis.

There is a lack of laboratory tests in clinical practice that can detect the activity of borrelial infection. This was the reason for testing an antigen-specific T-cell detection method in patients with neuroborreliosis: the ELISPOT method, which is capable of detecting antigen-specific T lymphocytes in clinical conditions. A group of 32 patients (20 diagnosed with neuroborreliosis; NB) was examined using this commercial method (LymeSpot intrerferon-γ Assay Kit®). Of these 20 NB patients, 10 were found to be positive and 10 negative; four of the five persons tested prior to the antibiotic treatment were positive. Eight patients served as the control group, giving four positive and four negative results. The results achieved so far appear to be unequivocal; still, the test could be expected: a) in non-specific clinical symptoms with borderline or negative proof of antibodies; b) in eraly stage of the disease; c) in the case of seropositivity and unequivocal clinical picture. The basic prerequisite for the clinical utilization of the method, however, is that it be thoroughly tested.

Prospective study on the chemokine CXCL13 in neuroborreliosis and other aseptic neuroinfections.

The study evaluates the clinical significance of CXCL13 (leukocyte chemoattractant synthesized in CSF ) in Lyme neuroborreliosis (LNB) and other aseptic CNS infections. 244 patients with symptoms of neuroinfection and/or LNB were divided into groups: A - patients with LNB-positive antibodies in serum and CSF (96) or CSF only (14); B - patients with aseptic non-borrelial neuroinfections (82); C - negative controls (52). Group A was divided into A1-A4 according to pleocytosis in CSF and AIIgG positivity. The highest CSF CXCL13 concentrations (max. 81,287.60pg/ml; median 1766.90pg/ml) were in A1 (positive AI, pleocytosis) and A3 (negative AIIgG, pleocytosis; max. 7201,60pg/ml, median 56.22pg/ml). A2 (positive AI without pleocytosis) and A4 (negative AI without pleocytosis) had low CXCL13 levels - A2 max. 650.50pg/ml (median<7.80pg/ml); A4 max. 118.56pg/ml (median<7.8pg/ml). In B the median was 28.10pg/ml (max. 595.87pg/ml). In C the CXCL13 concentrations were the lowest (max. 83.83pg/ml; median<7.80pg/ml). The lowest cut-off was 29pg/ml (sensitivity 90.0%, specificity 72.2%), the highest one 400pg/ml (sensitivity 59.6%, specificity 94.0%). The group differences of serum CXCL13 were insignificant. The highest concentrations were at the beginning of the disease. In LNB CXCL13 correlates better with the CSF pleocytosis than AI positivity.

DNA persistence after treatment of Lyme borreliosis.

One hundred twenty-four patients-53 with neuroborreliosis, 48 with erythema migrans, and 23 with Lyme arthritis-were tested in a prospective study for the presence of the DNA of Borrelia burgdorferi sensu lato in plasma, cerebrospinal fluid (CSF), urine, and synovial fluid by nested polymerase chain reaction (PCR). Specific DNA was detected using five amplification systems simultaneously: three targeted chromosomal genes encoding 16S rDNA, flagellin, and p66; and two plasmid sequences of OspA and OspC. Patients were examined clinically and by PCR before and after treatment and again after 3 and 6 months. Before treatment, the specific DNA was detected in 78 patients (62.9 %). Forty-one neuroborreliosis patients were DNA-positive (77.4 %), with CSF positivity in 26 patients, urine in 25, and plasma in 16. Twenty-six erythema migrans patients were DNA-positive (54.2 %), with plasma positivity in 18 cases and urine in 14. Eleven Lyme arthritis cases (47.8 %) were DNA positive (six in urine, five in plasma, and four in synovial fluid). The frequency of PCR positives was comparable in CSF and urine, and it was lower by approximately 50 % in plasma. Specific DNA was also found in a significant number of patients in later testing periods: 48 patients after treatment, 29 patients after 3 months, and 6 patients after 6 months. The prolonged PCR positivity was not explainable by persistent infection according to the clinical manifestations of the disease. Possible explanations of the problem are discussed.

[West Nile virus fever]. / Virus západonilské horecky (west Nile virus).

West Nile virus (WNV) is a member of the Flaviviridae family, genus Flavivirus. Its reservoir hosts are wild birds. Infection is transmitted to humans by infected mosquitoes of the genus Culex. In most cases, it is either asymptomatic or manifests itself as mild fever. Typically, WNV illnesshas a sudden onset with fever above 39 degrees C and accompanying symptoms such as chills, headache, arthralgia, myalgia, back ache, cough and sore throat. Gastrointestinal symptoms are frequently reported. Generalized lymphadenopathy and conjunctivitis may develop. In some patients the infection can progress to meningoencephalitis. Diagnosis is currently based on detection of IgM antibodies in blood and cerebrospinal fluid or direct detection of WNV RNA.

PCR in lyme neuroborreliosis: a prospective study.

OBJECTIVES: DNA proof is the only widely available direct diagnostic tool in Lyme borreliosis. Sensitive PCR detecting of spirochetal DNA was prepared and a prospective study in neuroborreliosis was performed. MATERIALS AND METHODS: 57 hospitalised patients with active neuroborreliosis and proved CSF antibodies synthesis were examined. Nested-PCR (utilizing three targets) was used for the detection of specific DNA in plasma, CSF and urine. RESULTS: Before treatment 36 positive patients (63.1%) were found in all tested specimens in parallel, 28 patients (49.1%) were positive in urine, 20 in CSF (35.0%) and 16 in plasma 28.0%). Later only urine was tested and the following results were obtained: 17 positive patients (30.0%) immediately after treatment, 8 (14.0%) after 3 months and one patient persisted positivity after 6 months. CONCLUSIONS: The highest sensitivity of PCR was achieved in the acute period of neuroborreliosis - 63.1% in three body fluids comparing with CSF antibody synthesis.