Predicting asymptomatic neurosyphilis using peripheral blood indicators

Ischemic stroke as a presenting feature of neurosyphilis in an immunocompetent adult and attained complete recovery following treatment: a case report and review of the literature

BACKGROUND

Neurosyphilis typically presents with nonspecific symptoms such as behavioral changes or cognitive impairment, rather than an initial stroke.

CASE PRESENTATION

This case report describes a Black African man in his thirties who experienced sudden weakness on the left side of his body. Computed tomography suggested a nucleo-capsular ischemic lesion. However, given his young age and lack of traditional stroke risk factors, further investigations were pursued. Laboratory tests revealed positive results for syphilis in both blood and cerebrospinal fluid. Additional imaging (head and neck angiography) indicated intracranial vasculitis with widespread and acute ischemia in the right hemisphere. Treatment with ceftriaxone and aspirin was initiated. Through ongoing monitoring and care, the patient's neurological condition improved.

CONCLUSION

The case underscores the critical need for prompt diagnosis and comprehensive assessment in patients experiencing stroke-like symptoms, especially in younger individuals. By recognizing neurosyphilis as a potential cause, healthcare providers can initiate timely treatment and improve patient outcomes.

Lymphocyte to monocyte ratio and lymphocyte to neutrophil ratio in neurosyphilis may affect the response to therapy and diagnostic efficacy

To investigate the effects of lymphocyte to monocyte ratio (LMR), lymphocyte to neutrophil ratio (LNR), and serum toluidine red unheated serum test (sero-TRUST) titers on the therapy response of HIV negative neurosyphilis (NS) patients after initial therapy. HIV negative NS patients who received initial therapy at the Second Hospital of Nanjing were selected as the research participants, and demographic data, as well as clinical and laboratory data, were collected through follow-up.Group the study population based on response to therapy status, with complete response to therapy as the endpoint of the study. Cox regression analysis of factors influencing response to therapy after initial therapy. Time-dependent ROC curve evaluation of LMR and LNR prediction ability. Among the 249 patients included in this study, 200 were in the response to therapy group and 49 were in the therapy non-response to therapy group. Cox regression analysis found that baseline blood LMR > 1.93, LNR > 0.3, and sero-TRUST titer > 1:16 can affect the response to therapy outcomes. However, there was no statistically significant difference between LMR and LNR with and without response in the therapy group. The time-dependent ROC curve shows that the AUC for evaluating response to therapy is moderately sensitive based on baseline sero-TRUST titers, or LNR after 3 months of therapy, sero-TRUST difference from baseline. Baseline blood LMR > 1.93 and sero-TRUST titers ≥ 1:16 may be important prognostic factors affecting response to therapy in HIV negative NS patients. Baseline sero-TRUST titer > 1:16, LNR increase > 0.12 or sero-TRUST titer decrease > 2-fold after 3 months of therapy can be used as auxiliary indicators to evaluate the occurrence of therapy response in patients.

Serum homocysteine levels as a predictor of neurosyphilis among HIV-negative syphilis patients: A single-center retrospective study

This study investigates the differences in peripheral blood parameters between patients with non-neurosyphilis and neurosyphilis, aiming to identify potential serum biomarkers to predict the occurrence of neurosyphilis and avoid unnecessary lumbar punctures. A retrospective analysis was conducted on 110 HIV-negative syphilis patients in this study. We found that the serum homocysteine (Hcy) levels in the non-neurosyphilis group, asymptomatic neurosyphilis group, and symptomatic neurosyphilis group were 12.30 (10.45, 13.25), 17.50 (12.03, 26.28), and 15.70 (13.70, 20.20), respectively. The serum Hcy levels in the asymptomatic neurosyphilis group and symptomatic neurosyphilis group were significantly higher than those in the non-neurosyphilis group (P<0.05). The AUC for serum Hcy in diagnosing neurosyphilis was 0.861 (95% CI: 0.715-0.950), with a sensitivity and specificity of 98.47% and 71.43% respectively. The study indicated that serum Hcy levels serve as a potential biomarker to differentiate neurosyphilis from non-neurosyphilis.

Neutrophil-related indicators as potential peripheral blood biomarkers for the diagnosis of neurosyphilis: a cross-sectional study

BACKGROUND

Neurosyphilis (NS) is the most serious complication elicited by the invasion of Treponema pallidum (T. pallidum) into the central nervous system. Identifying the neuro-invasion of T. pallidum as early as possible is important. Looking for indicators with good performance and convenient to operate is in great demand for the diagnosis of NS.

METHODS

A cross-sectional study was conducted on 428 human immunodeficiency virus (HIV)-negative syphilis patients who underwent therapy in Shanghai Skin Disease Hospital from April 2022 to June 2023. The syphilis patients were further grouped into non-neurosyphilis (NNS), asymptomatic neurosyphilis (ANS) and symptomatic syphilis (SNS). Laboratory examination results of these patients were analyzed.

RESULTS

Significantly elevated neutrophil CD64 (nCD64) index and neutrophil to lymphocyte ratio (NLR) were observed in ANS and SNS patients compared with those of NNS patients. nCD64 index and NLR were strongly correlated with serum and cerebrospinal fluid (CSF) TRUST titer, CSF WBC and CSF protein levels in NS patients. nCD64 index and NLR were independent factors influencing NS, especially ANS. Logistic regression models based on nCD64 index, NLR and serum TRUST titer exhibited better diagnostic performances to the currently used markers in NS diagnosis. Particularly, for NS patients with negative CSF TRUST, diagnostic performance of the combined nCD64 and NLR was obviously superior to CSF protein and CSF WBC.

CONCLUSIONS

Neutrophil-related indicators-nCD64 index and NLR have potential application value in the diagnosis of NS, especially for the CSF TRUST negative patients.

Refining a non-invasive prediction model for neurosyphilis diagnosis by using immunoassay to detect serum anti-TP0435 (TP17) and TP0574 (TP47) IgG antibodies: two-centre cross-sectional retrospective study in China

OBJECTIVES

Invasive lumbar puncture is the conventional method for diagnosing neurosyphilis (NS). We investigated a non-invasive alternative method to detect serum Treponema pallidum-specific antibodies against highly immunogenic antigens TP0171 (TP15), TP0435 (TP17), and TP0574 (TP47) by using luciferase immunosorbent assay.

METHODS

A total of 816 HIV-negative patients suspected of NS from the Beijing and Guangzhou cohorts were retrospectively selected and tested for serum anti-TP15, TP17, and TP47 IgG antibodies. Two diagnostic prediction models were developed using stepwise logistic regression in the Beijing cohort, and evaluated in the Guangzhou cohort for external validation.

RESULTS

Serum antibodies against TP15, TP17, and TP47 showed moderate capability for NS diagnosis in the Beijing cohort and the corresponding area under the receiver operating characteristic curves (AUCs) were 0.722 [95% confidence interval (CI): 0.680-0.762)], 0.780 (95% CI: 0.741-0.817), and 0.774 (95% CI: 0.734-0.811), respectively. An expanded NS prediction model integrated with anti-TP17 and anti-TP47 antibodies showed better performance than the base NS diagnostic model without anti-TP17 and anti-TP47 antibodies with the AUC of 0.874 (95% CI: 0.841-0.906) vs. 0.845 (95% CI: 0.809-0.881) (p = 0.007) in the development cohort, and 0.934 (95% CI: 0.909-0.960) vs. 0.877 (95% CI: 0.840-0.914) (p < 0.001) in validation cohort, respectively. Decision curve analysis revealed that the net benefit of the expanded model exceeded that of the base model when the threshold probability was between 0.10 and 0.95 in both the development and external validation cohorts.

DISCUSSION

Serum antibodies against TP17 and TP47 exhibited promising diagnostic capability for NS and significantly enhanced the predictive accuracy of model for NS diagnosis. Our study highlights the potential of serum treponemal antibody detection as a non-invasive method for NS diagnosis to substitute invasive lumbar puncture in NS diagnosis.

LC-MS metabolomics and lipidomics in cerebrospinal fluid from viral and bacterial CNS infections: a review

There is compelling evidence that a dysregulated immune inflammatory response in neuroinfectious diseases results in modifications in metabolic processes and altered metabolites, directly or indirectly influencing lipid metabolism within the central nervous system (CNS). The challenges in differential diagnosis and the provision of effective treatment in many neuroinfectious diseases are, in part, due to limited understanding of the pathophysiology underlying the disease. Although there are numerous metabolomics studies, there remains a deficit in neurolipidomics research to provide a comprehensive understanding of the connection between altered metabolites and changes in lipid metabolism. The brain is an inherently high-lipid organ; hence, understanding neurolipidomics is the key to future breakthroughs. This review aims to provide an integrative summary of altered cerebrospinal fluid (CSF) metabolites associated with neurolipid metabolism in bacterial and viral CNS infections, with a particular focus on studies that used liquid chromatography-mass spectrometry (LC-MS). Lipid components (phospholipids) and metabolites (carnitine and tryptophan) appear to be the most significant indicators in both bacterial and viral infections. On the basis of our analysis of the literature, we recommend employing neurolipidomics in conjunction with existing neurometabolomics data as a prospective method to enhance our understanding of the cross link between dysregulated metabolites and lipid metabolism in neuroinfectious diseases.

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

Objective

To examine the correlation of neutrophil CD64 (nCD64) index with neurosyphilis (NS) across different stages of syphilis.

Methods

A 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.

Results

Significant 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.

Conclusions

The nCD64 index may help to the diagnosis of NS in secondary and tertiary syphilis.

Prediction of clinical progression in nervous system diseases: plasma glial fibrillary acidic protein (GFAP)

Glial fibrillary acidic protein (GFAP), an intracellular type III intermediate filament protein, provides structural support and maintains the mechanical integrity of astrocytes. It is predominantly found in the astrocytes which are the most abundant subtypes of glial cells in the brain and spinal cord. As a marker protein of astrocytes, GFAP may exert a variety of physiological effects in neurological diseases. For example, previous published literatures showed that autoimmune GFAP astrocytopathy is an inflammatory disease of the central nervous system (CNS). Moreover, the studies of GFAP in brain tumors mainly focus on the predictive value of tumor volume. Furthermore, using biomarkers in the early setting will lead to a simplified and standardized way to estimate the poor outcome in traumatic brain injury (TBI) and ischemic stroke. Recently, observational studies revealed that cerebrospinal fluid (CSF) GFAP, as a valuable potential diagnostic biomarker for neurosyphilis, had a sensitivity of 76.60% and specificity of 85.56%. The reason plasma GFAP could serve as a promising biomarker for diagnosis and prediction of Alzheimer's disease (AD) is that it effectively distinguished AD dementia from multiple neurodegenerative diseases and predicted the individual risk of AD progression. In addition, GFAP can be helpful in differentiating relapsing-remitting multiple sclerosis (RRMS) versus progressive MS (PMS). This review article aims to provide an overview of GFAP in the prediction of clinical progression in neuroinflammation, brain tumors, TBI, ischemic stroke, genetic disorders, neurodegeneration and other diseases in the CNS and to explore the potential therapeutic methods.

Neurosyphilis: insights into its pathogenesis, susceptibility, diagnosis, treatment, and prevention

Background and aim

Invasion of the central nervous system by Treponema pallidum can occur at any stage of syphilis. In the event that T. pallidum is not cleared promptly, certain individuals may experience progression to neurosyphilis, which manifests as cognitive and behavioral abnormalities, limb paralysis, and potentially fatal outcomes. Early identification or prevention of neurosyphilis is therefore crucial. The aim of this paper is to conduct a critical and narrative review of the latest information focusing exclusively to the pathogenesis and clinical management of neurosyphilis.

Methodology

To compile this review, we have conducted electronic literature searches from the PubMed database relating to neurosyphilis. Priority was given to studies published from the past 10 years (from 2013 to 2023) and other studies if they were of significant importance (from 1985 to 2012), including whole genome sequencing results, cell structure of T. pallidum, history of genotyping, and other related topics. These studies are classic or reflect a developmental process.

Results

Neurosyphilis has garnered global attention, yet susceptibility to and the pathogenesis of this condition remain under investigation. Cerebrospinal fluid examination plays an important role in the diagnosis of neurosyphilis, but lacks the gold standard. Intravenous aqueous crystalline penicillin G continues to be the recommended therapeutic approach for neurosyphilis. Considering its sustained prominence, it is imperative to develop novel public health tactics in order to manage the resurgence of neurosyphilis.

Conclusion

This review gives an updated narrative description of neurosyphilis with special emphasis on its pathogenesis, susceptibility, diagnosis, treatment, and prevention.

Serum Ubiquitin C-Terminal Hydrolase-L1, Glial Fibrillary Acidic Protein, and Neurofilament Light Chain Are Good Entry Points and Biomarker Candidates for Neurosyphilis Diagnosis Among Patients Without Human Immunodeficiency Virus to Avoid Lumbar Puncture

BACKGROUND

Laboratory tests to diagnose neurosyphilis using cerebrospinal fluid (CSF) are currently disadvantageous as a lumbar puncture is required, which may result in patients with neurosyphilis missing an opportunity for early diagnosis. Thus, blood biomarker candidates that are more convenient and minimally invasive to collect for diagnosing neurosyphilis is urgently needed.

METHODS

This observational study aimed to analyze serum ubiquitin C-terminal hydrolase-L1 (UCH-L1), glial fibrillary acidic protein (GFAP), and neurofilament light chain (NF-L) levels in 153 patients without human immunodeficiency virus (HIV) and to evaluate their diagnostic performance in neurosyphilis compared with CSF.

RESULTS

Serum UCH-L1, GFAP, and NF-L levels were significantly higher in patients with neurosyphilis compared with patients with uncomplicated syphilis or non-syphilis. For the diagnosis of neurosyphilis, serum UCH-L1, GFAP, and NF-L revealed sensitivities of 90.20%, 80.40%, and 88.24%, and specificities of 92.16%, 78.43%, and 80.39%, respectively, at cutoff levels of 814.50 pg/mL, 442.70 pg/mL, and 45.19 pg/mL, respectively. In patients with syphilis, serum UCH-L1, GFAP, and NF-L levels correlated strongly or moderately with those in the CSF, with similar or better diagnostic performance than those in the CSF. The testing algorithms' sensitivity and specificity increased to 98.04% and 96.08%, respectively, when subjected to parallel and combination testing, respectively.

CONCLUSIONS

To avoid lumbar puncture, each serum UCH-L1, GFAP, and NF-L is a good entry point and biomarker candidate for the diagnosis of neurosyphilis among patients without HIV. These proteins used in concerto can further improve the diagnostic sensitivity and specificity.

MRI of neurosyphilis with mesiotemporal lobe lesions of "knife-cut sign” on MRI: A case report and literature review

Neurosyphilis with mesiotemporal lobe lesions remains a difficult entity to diagnose, especially when it mimics herpes simplex encephalitis (HSE). Here, we report what appeared to be the first case of mesiotemporal imaging of neurosyphilis presenting as a "knife-cut" sign and mimicking HSE pathological hallmarks on imaging. The magnetic resonance imaging (MRI) changes in neurosyphilis and HSE were indistinguishable in the initial diagnosis because of the common involvement of the mesiotemporal lobe. Neurosyphilis was diagnostically confirmed by positive readings in the treponema pallidum hemagglutination assay (TPHA), rapid plasma reagin (RPR) and cerebrospinal fluid-polymerase chain reaction (CSF-PCR) tests for Treponema pallidum infection. Neurosyphilis and HSE had similar clinical features and signs on MRI, except the knife-cut sign which is a common diagnosis in HSE. Therefore, neurosyphilis with mesiotemporal changes and knife-cut signs on MRI should be evaluated in the differential diagnosis in all patients, as similar changes may also occur in HSE patients. The literature review of published articles between 1997 and 2020 was conducted to further validate our clinical observations and discuss diagnostic and treatment options for neurosyphilis with mesiotemporal lobe lesions.

Impact of Asymptomatic Neurosyphilis on Patients Quality of Life and Social Stigma

Background/Objectives

Neurosyphilis is a disease caused by Treponema pallidum when it invades the central nervous system. Asymptomatic neurosyphilis (ANS) is one of the most common types of neurosyphilis, however it is often misdiagnosed. This study aimed to explore the impact of ANS on patient's quality of life and social stigma.

Methods

A total of 159 ANS patients were diagnosed by their serology and cerebrospinal fluid. These patients' stigma and quality of life were assessed separately through the Social Impact Scale (SIS) and the Easy Response Questionnaire.

Results

The average age was 36.25±8.36 years old, and 114 patients were males (71.69%). The serum syphilis test of 159 selected patients was positive, and the indicators of nucleus cells, protein quantification, and syphilis antibodies in the cerebrospinal fluid met the criteria for ANS. The total stigma score was (40.23 ±10.12), with the scores of the different entries being clearly differentiated, with the highest being the 15th entry (I feel I need to keep my illness a secret), with an average score of 3.15/4.

Conclusion

Patients with asymptomatic neurosyphilis may feel social stigma and are more negative when facing their disease. Health-care workers should be aware of the particular aspects of their condition and pay special attention to the need for patient privacy.

Serum Interleukin-26 is a Potential Biomarker for the Differential Diagnosis of Neurosyphilis and Syphilis at Other Stages

Background

Interleukin-26 (IL-26) is an atypical proinflammatory cytokine due to its binding to circulating double-stranded DNA and direct antibacterial activity. Although IL-26 has been confirmed to be involved in the pathophysiology of cancer, chronic inflammatory diseases and infections, the diagnostic and prognostic values of IL-26 levels in syphilis patients are not clear. This study aimed to investigate IL-26 levels in different stages of syphilis progression.

Methods

A total of 30 healthy controls and 166 patients with syphilis at different stages of disease progression were enrolled. Serum IL-26 levels were quantified in accordance with the protocols of RayBio^® Human Interleukin-26 Enzyme Linked Immunosorbent Assay (ELISA) kits. Clinical laboratory diagnostic parameters and blood analysis data were detected and collected according to clinical medical laboratory standards.

Results

The levels of serum IL-26 were significantly higher in neurosyphilis patients than in healthy subjects (6.87 (4.36, 12.14) and 1.67 (0.09, 4.89) pg/μL, respectively; ****p < 0.0001), latent syphilis (1.48 (0.40, 2.05) pg/μL, ****p < 0.0001), seroresistant syphilis (0.81 (0.20, 2.91) pg/μL, ****p < 0.0001) and secondary syphilis (1.66 (0.41, 4.25) pg/μL, ****p < 0.0001) with data presented as the median with interquartile range. The concentration of serum IL-26 was most sensitive to serum low-density lipoprotein concentration (r = -0.438, **p = 0.004) in latent syphilis, urine epithelial cells (r = 0.459, **p = 0.003) in seroresistant syphilis, and serum creatinine levels (r = 0.463, **p = 0.004) and urea creatinine ratio levels (r = 0.500, **p = 0.008) in secondary syphilis patients. There was no significant correlation with the concentration of IL-26 and toluidine red unheated serum test (TRUST) titers in each type of syphilis patient.

Conclusion

Circulating IL-26 in serum displays diagnostic potential in the progression of neurosyphilis and warrants further evaluation in clinical trials.