Neurosyphilis In Patients Research Articles

Clinical and Laboratory Characteristics, Diagnosis, and Treatment of Patients with Neurosyphilis in Emergency Department: A Retrospective Study of 12 Patients.

Syphilis, caused by Treponema pallidum, presents a diagnostic challenge due to its diverse clinical manifestations. Neurosyphilis has seen a resurgence in recent years, particularly among men who have sex with men and those living with HIV. Diagnosis of neurosyphilis in emergency settings is challenging due to its varied neurological presentations. This study aims to serve as a reference for dermatologists and neurologists in diagnosing and treating neurosyphilis. This retrospective study analyzed patients who presented with neuropsychiatric symptoms and were ultimately diagnosed with neurosyphilis. These patients were collected from the emergency department in Peking Union Medical College Hospital between January 2018 and November 2023. The medical history, clinical symptoms, laboratory examinations, cranial MRI characteristics, and treatment regimens of these patients were investigated. Among the included 12 neurosyphilis patients, memory deterioration was observed in 8 out of the 12 neurosyphilis patients. Diagnosis often resulted in delays, with misdiagnoses mainly including Alzheimer's disease, stroke, and epilepsy. Neuroimaging revealed various abnormalities, predominantly affecting ventricular and temporal regions. Treatment with penicillin-based regimens varied in compliance, with only a minority of patients adhering to guidelines. Treatment outcomes were inconsistent, with some patients experiencing irreversible neurological damage and fluctuating serum rapid plasma reagin (RPR) titers. Diagnosis of neurosyphilis in the emergency department remains challenging, necessitating awareness of its varied neurological presentations. Enhanced diagnostic strategies are imperative to accelerate treatment initiation and improve outcomes for affected individuals.

Neurosyphilis patients presenting with ocular motor cranial nerve palsy in the modern antibiotic era: Case series from two centers and review of the literature

BackgroundSyphilis can mimic the clinical features of many neurological disorders and cause ocular motor cranial nerve palsy (OMCNP). This study aims to characterize the clinical features of neurosyphilis patients presenting with OMCNP. Methods In a retrospective study and literature review, demographic data, clinical presentations, laboratory findings, radiological findings, treatment approaches, and outcomes were recorded and analyzed. ResultsOverall, 0.74 % and 1.64 % of patients presenting to two institutes exhibited syphilitic OMCNP, respectively. A total of 32 patients (23 from the literature) were recruited, with a median age of 46 years and a predominance of males (81.3 %). Meningovascular neurosyphilis was diagnosed in 29 patients (90.6 %), and tabes dorsalis was found in 3 patients (9.4 %). Unilateral OMCNP was present in 24 patients (65.5 %). Unilateral sixth nerve palsy was observed in 10 patients (34.5 %), followed by unilateral third nerve palsy in 9 patients (31.0 %), and unilateral multiple OMCNP in 5 patients (17.2 %). A total of 12 patients (41.4 %) presented with isolated OMCNP, and 4 of these individuals developed other neurological deficits during the disease. Pupillary involvement was found in all patients who presented unilateral third nerve palsies. After treatment, 17 patients (58.6 %) achieved complete recovery of ocular motility; 6 patients (20.7 %) achieved partial recovery; 5 patients (17.2 %) remained stable; and 1 patient (3.5 %) became progressive. ConclusionsPatients presenting with OMCNP alone or combined with other cranial nerve deficits should be screened for neurosyphilis, and the standard treatment regimen should be initiated if a diagnosis of neurosyphilis is established.

Cerebrospinal fluid CXCL13 concentration for diagnosis of neurosyphilis: a systematic review and meta-analysis

ObjectiveTo systematically assess the diagnostic accuracy of CXCL13 testing of cerebrospinal fluid (CSF) for neurosyphilis diagnosing.DesignSystematic review and meta-analysis.Data sourcesPubMed, Embase, Cochrane Library and Web of Science databases from their...

Letter in response to “Frequency of asymptomatic neurosyphilis in patients with latent syphilis: A 4-year retrospective study from a tertiary care center”

Letter in response to “Frequency of asymptomatic neurosyphilis in patients with latent syphilis: A 4-year retrospective study from a tertiary care center”

Neutrophil CD64 index as a potential blood biomarker for the diagnosis of neurosyphilis in secondary and tertiary syphilis: A retrospective study

ObjectiveTo examine the correlation of neutrophil CD64 (nCD64) index with neurosyphilis (NS) across different stages of syphilis. MethodsA total of 1243 syphilis patients at different stages (344 of primary, 385 of secondary, and 514 of tertiary) included in this study were divided into NS and non-NS (NNS). Correlations of nCD64 index with currently used syphilis biomarkers were explored using Spearman correlation test. Relationships between nCD64 index and NS at different stages were investigated by stratified analysis and restricted cubic spline model. The diagnostic performance of nCD64 index for NS was assessed by receiver operating characteristic (ROC) curve. ResultsSignificant statistical correlations of nCD64 index with cerebrospinal fluid (CSF) NS indicators were found in secondary and tertiary syphilis. Increased nCD64 index was associated with increased risk of NS in secondary and tertiary syphilis. ROC analysis values further confirmed the diagnostic potential of nCD64 index for NS. Marked decrease of nCD64 index was observed in NS patients after effective antisyphilitic treatments. ConclusionsThe nCD64 index may help to the diagnosis of NS in secondary and tertiary syphilis.

An observational prospective study based on a large cohort of HIV-negative neurosyphilis patients with particular reference to the Jarisch-Herxheimer reaction.

The purpose of this study is to outline a complete picture of Jarisch-Herxheimer reaction (JHR) in the central nervous system among HIV-negative neurosyphilis patients. A prospective study cohort of 772 cases with almost all stages of neurosyphilis depicted the features of JHR including occurrence rate, risk profiles, clinical manifestations, medical management and prognosis. The total occurrence rate of JHR was 9.3% (95% CI, 7.3-11.4%), including 4.1% (95% CI, 2.7-5.6%) with severe JHR. The reaction started 5h after treatment initiation, peaked after 8h, and subsided after 18h. Patients with severe JHR experienced a longer recovery time (26h). Patients with general paresis (OR = 6.825), ocular syphilis (OR = 3.974), pleocytosis (OR = 2.426), or a high CSF-VDRL titre (per log2 titre increase, OR = 2.235) were more likely to experience JHR. Patients with general paresis had an 11.759-fold increased risk of severe JHR. Worsening symptoms included cognitive impairment, mania, nonsense speech, and dysphoria, while symptoms of hallucination, urination disorder, seizures, myoclonus, or aphasia appeared as new-onset symptoms. Neurosyphilis treatment did not need to be interrupted in most patients with JHR and could be reinstated in patients with seizures under supportive medication when JHR subsided. Severe JHR displayed a 4.1% occurrence rate and clinicians should pay particular attention to patients at a higher risk of JHR. The neurosyphilis treatment regime can be restarted under intensive observation for patients with severe JHR and, if necessary, supportive medication should be initiated and continued until the end of therapy.

ADAMTS5 Promotes Permeability of the Blood-Brain Barrier during Treponema pallidum Subspecies pallidum Invading the Central Nervous System.

The pathogenesis of neurosyphilis remains unclear. A previous study found a noteworthy up-regulation of a disintegrin and metalloproteinase with thrombospondin type 1 motif 5 (ADAMTS5) gene in human brain microvascular endothelial cells cocultured with Treponema pallidum subspecies pallidum (Tp). To investigate the ADAMTS5 role in Tp invading the central nervous system (CNS), we conducted relevant experiments. Our study revealed that Tp caused an increase in human cortical microvascular endothelial cell/D3 (hCMEC/D3) barrier permeability and significantly enhanced ADAMTS5 expression. The heightened permeability of the hCMEC/D3 barrier was effectively mitigated by inhibiting ADAMTS5. During this process, Tp promoted interleukin-1β production, which, in turn, facilitated ADAMTS5 expression. Furthermore, Tp significantly reduced the glycocalyx on the surface of hCMEC/D3 cells, which was also ameliorated by inhibiting ADAMTS5. Additionally, ADAMTS5 and endothelial glycocalyx components notably increased in the cerebrospinal fluid of HIV-negative neurosyphilis patients. This research provided the first demonstration of the ADAMTS5 role in Tp invading the CNS and offered new insight into neurosyphilis pathogenesis.

Frequency of asymptomatic neurosyphilis in patients with latent syphilis: A 4-year retrospective study from a tertiary care center

Frequency of asymptomatic neurosyphilis in patients with latent syphilis: A 4-year retrospective study from a tertiary care center

Clinical and laboratory features of neurosyphilis: A single-center, retrospective study of 402 patients

Neurosyphilis is a serious global health issue and a big challenge in developing countries, related risk factors should be taken seriously. Although there are a certain number of studies describing the clinical and laboratory features and risk factors for symptomatic neurosyphilis (SNS), but some risk factors are still controversial. The aim of this research is to investigate the association between asymptomatic neurosyphilis (ANS) and symptomatic neurosyphilis (SNS) and identify risk factors for SNS. This was a single-center retrospective study in a tertiary hospital in Hangzhou, China. The clinical and laboratory features of neurosyphilis patients from January 1, 2011 to July 31, 2020 were retrospectively reviewed. After detailed assessments based on diagnostic criteria, 402 patients with neurosyphilis were enrolled in this study. There were 299 male and 103 female patients. The median age was 53.5 (45, 61) years. Multivariable logistic regression displayed that SNS were correlated with the following factors: male, without anti-syphilis treatment, high pretreatment serum RPR titer and positive CSF RPR. Our findings suggest a potential association between SNS and specific factors, including male gender, elevated pretreatment serum and CSF RPR titers. Moreover, our observations indicate that individuals without anti-syphilis treatment may be at a higher likelihood of manifesting the symptomatic form. This underscores the importance of considering gender, RPR titers, and treatment status as significant contributors to the risk profile for SNS.

Large-Scale Proteome Profiling Identifies Biomarkers Associated with Suspected Neurosyphilis Diagnosis.

Neurosyphilis (NS) is a central nervous system (CNS) infection caused by Treponema pallidum (T. pallidum). NS can occur at any stage of syphilis and manifests as a broad spectrum of clinical symptoms. Often referred to as "the great imitator," NS can be easily overlooked or misdiagnosed due to the absence of standard diagnostic tests, potentially leading to severe and irreversible organ dysfunction. In this study, proteomic and machine learning model techniques are used to characterize 223 cerebrospinal fluid (CSF) samples to identify diagnostic markers of NS and provide insights into the underlying mechanisms of the associated inflammatory responses. Three biomarkers (SEMA7A, SERPINA3, and ITIH4) are validated as contributors to NS diagnosis through multicenter verification of an additional 115 CSF samples. We anticipate that the identified biomarkers will become effective tools for assisting in diagnosis of NS. Our insights into NS pathogenesis in brain tissue may inform therapeutic strategies and drug discoveries for NS patients.

Cerebrospinal fluid CXCL13 concentration for diagnosis and monitoring of neurosyphilis in people with HIV.

The study aimed to assess and compare cerebrospinal fluid (CSF)-CXCL13 levels in People with HIV (PWH) with suspected neurosyphilis (NS), those with syphilis but without NS, and patients without treponema infection. Additionally, it aimed to evaluate changes in CSF-CXCL13 concentrations before and after antibiotic treatment. This was a prospective cohort study involving 93 PWH suspected of NS. All participants underwent lumbar puncture, with CSF-CXCL13 levels measured at baseline and during follow-up in patients diagnosed with NS. CSF-CXCL13 levels were quantified using ELISA. The Mann-Whitney U test was used to analyze differences between groups, while the Wilcoxon test assessed within subject changes. ROC curve analysis determined the diagnostic efficacy of CSF-CXCL13 for NS. Significantly higher CSF-CXCL13 levels were observed in patients with NS compared to those with syphilis without NS and non-syphilis patients. Posttreatment, a decline in CSF-CXCL13 levels was noted in all NS cases. A CSF-CXCL13 threshold exceeding 60.0 pg/ml, in conjunction with reactive CSF-FTA-ABS, yielded a sensitivity of 88.9% and a specificity of 97.6% for NS diagnosis. CSF-CXCL13 emerges as a valuable adjunctive biomarker for detecting NS in PWH, especially in cases with nonreactive CSF-VDRL. Monitoring CSF-CXCL13 levels also appears effective in evaluating therapeutic response in PWH undergoing NS treatment.

Neurological manifestations of syphilis-HIV coinfection in South Africa

ObjectiveSyphilis and HIV coinfection is highly prevalent in South Africa, and both can cause neurological complications. We describe the clinical presentation and outcome of neurosyphilis in patients with and without HIV coinfection diagnosed at a tertiary facility, Groote Schuur Hospital (GSH), in South Africa. MethodsWe retrospectively analyzed folders of adults with positive cerebrospinal fluid (CSF) fluorescent treponemal antibody absorption test in 2018 and 2019, with follow-up data collected until 2022. ResultsHIV-coinfection was identified in 35% of the 69 included patients. Patients with HIV-coinfection were more likely to be female (58% vs 25% female, p < 0.01), and present earlier (median age = 31 years vs. 40 years, p < 0.001). Neuropsychiatric manifestations (confusion, dementia, psychosis), and strokes were the commonest clinical presentations in both groups. Those with HIV-coinfection were significantly less likely to be diagnosed with neurosyphilis by the treating clinician (71% vs. 91%, p < 0.05), as were those with a negative CSF Venereal Disease Research Laboratory (74% vs. 94%, p < 0.05). Accurate diagnosis of neurosyphilis was associated with an increased 12-month survival (alive: N = 36 [63%]) relative to those who did not receive an accurate diagnosis (alive: N = 2 [17%], p < 0.05). Those who were optimally treated with antibiotics had significantly higher 12-month survival (alive: N = 33, 63%) compared to those with suboptimal treatment (alive: N = 5, 29%), p < 0.01. ConclusionNeurosyphilis presented similarly in those with and without HIV-coinfection. Accurate identification and optimal antibiotic treatment of neurosyphilis, particularly in CSF VDRL negative patients and those with HIV-coinfection, is necessary to improve patient survival.

Treponema pallidum promoted microglia apoptosis and prevented itself from clearing by human microglia via blocking autophagic flux.

Treponema pallidum (Tp) has a well-known ability to evade the immune system and can cause neurosyphilis by invading the central nervous system (CNS). Microglia are resident macrophages of the CNS that are essential for host defense against pathogens, this study aims to investigate the interaction between Tp and microglia and the potential mechanism. Here, we found that Tp can exert significant toxic effects on microglia in vivo in Tg (mpeg1: EGFP) transgenic zebrafish embryos. Single-cell RNA sequencing results showed that Tp downregulated autophagy-related genes in human HMC3 microglial cells, which is negatively associated with apoptotic gene expression. Biochemical and cell biology assays further established that Tp inhibits microglial autophagy by interfering with the autophagosome-lysosome fusion process. Transcription factor EB (TFEB) is a master regulator of lysosome biogenesis, Tp activates the mechanistic target of rapamycin complex 1 (mTORC1) signaling to inhibit the nuclear translocation of TFEB, leading to decreased lysosomal biogenesis and accumulated autophagosome. Importantly, the inhibition of autophagosome formation reversed Tp-induced apoptosis and promoted microglial clearance of Tp. Taken together, these findings show that Tp blocks autophagic flux by inhibiting TFEB-mediated lysosomal biosynthesis in human microglia. Autophagosome accumulation was demonstrated to be a key mechanism underlying the effects of Tp in promoting apoptosis and preventing itself from clearing by human microglia. This study offers novel perspectives on the potential mechanism of immune evasion employed by Tp within CNS. The results not only establish the pivotal role of autophagy dysregulation in the detrimental effects of Tp on microglial cells but also bear considerable implications for the development of therapeutic strategies against Tp, specifically involving mTORC1 inhibitors and autophagosome formation inhibitors, in the context of neurosyphilis patients.

Neurosyphilis in patients at a university hospital in the central west region of Brazil

Neurosyphilis in patients at a university hospital in the central west region of Brazil

Establishment of HIV-negative neurosyphilis risk score model based on logistic regression

ObjectiveTo establish the risk scoring model for HIV-negative neurosyphilis (NS) patients and to optimize the lumbar puncture strategy.MethodsFrom 2016 to 2021, clinical information on 319 syphilis patients was gathered. Multivariate logistic regression was used to examine the independent risk factors in NS patients who tested negative for human immunodeficiency virus (HIV). Receiver operating characteristic curves (ROC) were used to assess the risk scoring model’s capacity for identification. According to scoring model, the timing of lumbar puncture was suggested.ResultsThere were statistically significant differences between HIV-negative NS and non-neurosyphilis (NNS) patients in the following factors. These included age, gender, neuropsychiatric symptoms (including visual abnormalities, hearing abnormalities, memory abnormalities, mental abnormalities, paresthesia, seizures, headache, dizziness), serum toluidine red unheated serum test (TRUST), cerebrospinal fluid Treponema pallidum particle agglutination test (CSF-TPPA), cerebrospinal fluid white blood cell count (CSF-WBC), and cerebrospinal fluid protein quantification (CSF-Pro) (P < 0.05). Logistic regression analysis of HIV-negative NS patients risk factors showed that age, gender, and serum TRUST were independent risk factors for HIV-negative NS (P = 0.000). The total risk score (− 1 ~ 11 points) was obtained by adding the weight scores of each risk factor. And the predicted probability of NS in HIV-negative syphilis patients (1.6 ~ 86.6%) was calculated under the corresponding rating. ROC calculation results showed that the score had good discrimination value for HIV-negative NS and NNS: area under the curve (AUC) was 0.80, the standard error was 0.026 and 95% CI was 74.9–85.1% (P = 0.000).ConclusionThe risk scoring model in this study can classify the risk of neurosyphilis in syphilis patients, optimize the lumbar puncture strategy to a certain extent, and provide ideas for the clinical diagnosis and treatment of HIV-negative neurosyphilis.

Secondary immunoreaction in patients with neurosyphilis and its relevance to clinical outcomes.

Several reported cases of autoimmune conditions such as anti-NMDAR encephalitis and neuromyelitis optica (AQP4) have been considered to be potentially secondary to Treponema pallidum infection. Since the role of immune impairment in neurosyphilis is unclear, in this retrospective study, we examined the correlation of the immune impairment in patients with neurosyphilis with their clinical characteristics and outcomes. Clinical information was collected from patients with neurosyphilis in our center from January 2019 to December 2021. Cerebrospinal fluid (CSF) samples were subjected to indirect immunofluorescence tissue-based assay (IIF-TBA) on mouse brain sections and cell-based assay (CBA). The clinical characteristics and treatment outcomes of TBA-positive and-negative patients were compared. A total number of 81 patients diagnosed with neurosyphilis were included. The results of the CBA tests showed that three cases had anti-NMDAR, AQP4, or GAD65 antibodies, respectively. By TBA test, 38 patients (38/81, 46.9%) had positive immunostains, including staining of neuronal cells in 21 cases (21/38, 55.3%), glial cells in 11 cases (11/38, 28.9%), and neuronal and glial cells in six cases (6/38, 15.8%). We then compared the clinical characteristics and treatment outcomes between the TBA-positive and-negative patients and found that TBA-positive staining was significantly correlated with syphilis antibody titers (p = 0.027 for serum and p = 0.006 for CSF) and head MRI abnormalities (p < 0.001 for parenchymal abnormalities and p = 0.013 for white matter lesions). The cognitive prognosis of TBA-positive neurosyphilis patients was significantly worse than that of TBA-negative patients (p < 0.001). The correlation between the TBA results and clinical data of our neurosyphilis patients imply the presence of secondary immune damage, which affected their prognosis. Therefore, TBA can be used as an additional biomarker for neurosyphilis patient prognosis.

The optimum condition of the toluidine red unheated serum test for the replacement of the venereal disease research laboratory test in cerebrospinal fluid for neurosyphilis diagnosis

BackgroundThe cerebrospinal fluid (CSF) venereal disease research laboratory (VDRL) test remains the standard for the laboratory diagnosis of neurosyphilis. The toluidine red unheated serum test (TRUST) is an alternative to the VDRL test as a serological test for syphilis, but it lacks guidelines for its use in CSF for neurosyphilis diagnosis. MethodsA total of 210 suspected neurosyphilis patients were included, consisting of 124 neurosyphilis patients and 86 syphilis/non-neurosyphilis patients. The TRUST was modified into the CSF-TRUST-10 test with 10 μL of antigen by referring to the CSF-VDRL test, and the CSF-TRUST-17 test with 17 μL of antigen by referring to its procedures in serum. The diagnostic performance of the CSF-TRUST-10 and CSF-TRUST-17 tests and the concordance between them and the CSF-VDRL test were evaluated. ResultsThe diagnostic performance of the CSF-TRUST-10 and CSF-TRUST-17 tests for diagnosing neurosyphilis were comparable to the CSF-VDRL test, as well as the positive rate. The agreement rate was 98.7% between the qualitative CSF-TRUST-10 and CSF-VDRL tests. A total of 91.4% of the quantitative CSF-TRUST-10 results were consistent with the CSF-VDRL test, and the discordant results were no more than two titres. The agreement rate was 98.1% between the qualitative CSF-TRUST-17 and CSF-VDRL tests and 87.6% between the quantitative CSF-TRUST-17 and CSF-VDRL tests. ConclusionsThe CSF-TRUST with 10 μL of antigen could be an alternative for the CSF-VDRL test for neurosyphilis diagnosis. Our results provide a basis for using the TRUST to guide the diagnosis of neurosyphilis.

Neurosyphilis among people with and without HIV infection: A Danish nationwide prospective, population-based cohort study 2015–2021

Comparative data on clinical presentation, laboratory characteristics, treatment, and outcome of neurosyphilis (NS) in people living with HIV (PLWH) and NS patients without HIV are scarce. Nationwide, population-based, prospective cohort study on all adults with NS diagnosed between 2015 and 2021 at departments of infectious diseases in Denmark. We identified 108 patients with NS, which equals a yearly incidence of 0.3/100,000 adults. The median age was 49 years, 85 (79%) were male, 43 (40%) were men having sex with men and 20 (22%) were PLWH. Ninety-five (88%) had early NS, 37 (34%) had ocular or ocular and otogenic NS, and 27 (25%) had symptomatic meningitis. Most common symptoms were visual disturbance (44%), skin rash (40%), fatigue (26%) and chancre (17%). Median CSF leukocyte count was 27×106 cells/L. PLWH less often had neurological deficits (p=0.02). Unfavorable outcome was observed in 23 (21%) at discharge of whom 0 were PLWH (p=0.01). Among the 88 NS patients without HIV a CSF leukocyte count of ≥30×106 cells/L was associated with unfavorable outcome (OR=3.3 (95% confidence interval: 1.1-10.4)). PLWH with NS have better outcomes than NS patients without HIV infection.

Investigation of the role of interleukin 27 in the immune regulation of Treg and Th17 cells in neurosyphilis patients.

Neurosyphilis (NS) is known as a sexually transmitted disease that is very difficult to diagnose and its diagnosis is delayed. Some studies have suggested that the level of interleukin (IL)-27 decreases in syphilis patients and the level of IL-17 increases in these patients, and these immunological changes can be a therapeutic target for these patients. The present study aims to evaluate IL-27's role in the immune regulation of Treg and Th17 cells in NS patients. 400 documented diagnosed syphilis patients were enrolled to the study and divided into two groups of neurosyphilis (NS) and non-neurosyphilis (S). Also 40 healthy volunteers were enrolled as a healthy control group (C). Peripheral blood mononuclear cells (PBMCs) from peripheral blood and cerebrospinal fluid (CSF) by lumbar puncture were collected as samples. mRNA expression and level of IL-27, IL-17, Th17, IL-17-producing CD4 + T cells and also protein concentration and VDRL of CSF were investigated. To obtain proposed results, flow cytometry, RT-PCR and ELISA were used. The mRNA expression of IL-27 in PBMCs declined significantly in NS patients compared to healthy controls ( p = 0.002) and S patients ( p = 0.005) and decreased significantly in CSF of NS patients in comparison to healthy controls ( p = 0.002) and S patients ( p = 0.003). The frequency of IL-17-producing CD4 + T cells increased significantly in PBMCs of NS patients in comparison to healthy controls ( p = 0.004) and S patients ( p = 0.004). This frequency also increased significantly in CSF of NS patients compared to C ( p = 0.007) and S patients ( p = 0.003). Adding rIL-27 significantly prevented the frequency of IL-17-producing CD4 + T cells from naïve CD4 + T cells under Th17 polarizing conditions from NS patients ( p = 0.043), C ( p = 0.043), and S patients ( p = 0.002) in PBMCs, and also 0.03, 0.02 and 0.03 respectively for NS, S and C of CSF. The results revealed a significant negative relationship between CSF protein and VDRL concentrations and CSF IL-27 levels. This study confirms previous efforts on the critical role of IL-17 in NS. Also, it supports other results on the inhibitory effects of IL-27 on the therapeutic potential of IL-27 in NS and the inflammation process.

Comparison of Treponema-specific immunoglobulin G (IgG) index with Treponema pallidum particle agglutination (TPPA) index for detection of intrathecal Treponema-specific antibody synthesis for serological diagnosis of neurosyphilis.

The determination of Treponema-specific intrathecal immunoglobulin synthesis with the Treponema pallidum particle agglutination (TPPA) index is a well-established method recommended in German guidelines for the diagnosis of neurosyphilis. However, the TPPA test is no longer available. The aim of this study was to evaluate whether the determination of a Treponema-specific immunoglobulin G (IgG) index can substitute the TPPA index. Serum and cerebrospinal fluid (CSF) samples from patients with confirmed (n=6) and probable (n=3) neurosyphilis as well as patients with adequately treated syphilis without neurosyphilis (n=4) were investigated. In addition to index calculation further CSF parameters were determined. The results of the Treponema IgG and the TPPA index were consistent in all patients with confirmed neurosyphilis and non-neurosyphilis patients. In two patients with probable neurosyphilis the IgG index appeared more plausible than the TPPA index when taking into account all available laboratory and clinical data of the patients. In conclusion, the determination of Treponema-specific intrathecal immunoglobulin synthesis with the IgG index appears to be a suitable alternative to the TPPA index.