Neurosyphilis

Neurosyphilis: An Uncommon Diagnosis in the Antibiotic Era

Neurosyphilis results from infection of the nervous system by Treponema pallidum. The diagnosis of neurosyphilis is overlooked because of its rarity. It can manifest as early or late symptoms after primary infection with syphilis, with symptoms lying on the spectrum of asymptomatic early neurosyphilis, syphilitic meningitis, meningovascular syphilis, general paresis, and tabes dorsalis. In this report, we present a case of neurosyphilis presenting with acute confusion and agitation.

Computational drug design for neurosyphilis disease by targeting Phosphoglycerate Kinase in Treponema pallidum with enhanced binding affinity and reduced toxicity

Neurosyphilis, a severe neurological complication of syphilitic infection caused by the gram-negative spirochete Treponema pallidum poses significant challenges in treatment due to its irregular physiology and lack of efficacy in present therapeutic strategies. Here, we report a new approach to developing drug treatment that targets the enzyme phosphoglycerate kinase (PGK), an essential component of the T. pallidum glycolytic pathway. Therefore, a ligand was designed involving common neuroprotectant elements reported from literature by a computational drug design method, to increase their binding energy with lower toxicity. The calculated binding affinity of the designed ligand with PGK was analyzed by molecular docking to be - 116.68 kcal/mol. Also, interaction analysis predicted that there are 5 hydrophobic bonds and 3 hydrogen bonds present between the docked complex. Afterward, in-silico ADMET studies were conducted for the designed ligand that determined a strong pharmacological profile with good absorption, zero violation of Lipinski's rule, and non-toxic properties. DFT analysis further optimized the ligand with a HOMO/LOMO gap value of 0.01421 kcal/mol indicating higher reactivity and enhanced electronic interactions, improving ligand efficiency. Moreover, pharmacophore modeling confirmed the reactive nature of the ligand. Furthermore, MD simulations showed stability in the overall structure. The output shows that our optimized ligand has statistically better binding affinity than the currently used drug penicillin, with improved pharmacokinetic profiles. This work demonstrates the importance of ligand design for the discovery of new drugs to treat neurosyphilis.

Infectious Neuropathies

This review explores diverse infectious etiologies of peripheral nervous system (PNS) dysfunction, spanning sensory and motor neurons, nerves, and associated structures. Progress in viral and bacterial infections reveals multifaceted mechanisms underlying neuropathies, including viral neurotoxicity and immune-mediated responses. Latest diagnostic advances facilitate early PNS complication detection, with ongoing research offering promising treatment avenues. Emerging pathogens like severe acute respiratory syndrome coronavirus 2, Zika virus, and EV-D68 highlight the evolving infectious neuropathy paradigm. Recognizing characteristic patterns and integrating clinical factors are pivotal for precise diagnosis and tailored intervention. Challenges persist in assessment and management due to varied pathogenic mechanisms. Advancements in understanding pathogenesis have improved targeted therapies, yet gaps remain in effective treatments. Ongoing research is crucial for optimizing approaches and improving patient outcomes.

Uncommon Neurosyphilis: Subacute Meningomyelitis with Distinctive "Candle Guttering Appearance"

In this article, we presented an exceedingly rare clinical case of neurosyphilis, radiological revealed a distinctive "candle guttering appearance." Posttreatment for syphilis, both clinical symptoms and radiological markers showed complete resolution.

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.

Mechanisms of Neurosyphilis-Induced Dementia: Insights into Pathophysiology

Neurosyphilis-induced dementia represents a severe manifestation of tertiary syphilis, characterized by cognitive and neuropsychiatric impairments. This condition arises from the progression of syphilis to the central nervous system, where the spirochete causes damage through invasion, chronic inflammation, and neurodegeneration. The pathophysiology involves chronic inflammatory responses, direct bacterial damage, and proteinopathies. Treponema pallidum triggers an inflammatory cascade, resulting in neuronal injury and synaptic dysfunction. Abnormal protein accumulations, including TAR DNA-binding protein 43 (TDP-43) and tau, contribute to neuronal loss and cognitive decline. Seizures, psychiatric symptoms, and motor deficits further complicate the progression of dementia. Diagnosis includes clinical assessment, cerebrospinal fluid analysis, and neuroimaging. Diagnostic tests include CSF-VDRL, FTA-ABS, and neuroimaging techniques such as MRI and PET scans, which help detect structural changes and confirm neurosyphilis. Management of neurosyphilis-induced dementia involves antibiotic therapy and psychotropic medications to address both infectious and symptomatic components. While penicillin remains the cornerstone of treatment, psychotropic agents, including haloperidol, risperidone, quetiapine, and divalproex sodium, can manage psychiatric symptoms. However, careful monitoring is required due to potential side effects and interactions with ongoing treatment. Overall, early diagnosis and comprehensive management are crucial for mitigating the cognitive and neuropsychiatric impairments associated with neurosyphilis-induced dementia.

Deciphering the Great Imitator: Syphilis and Neurosyphilis

Syphilis is an infectious disease caused by Treponema pallidum. Often known as the "great imitator," it has periods of active disease and periods of latency. Serologic syphilis testing can be divided into treponemal and non-treponemal tests, and multiple tests are required to prove infection. Standardized algorithms exist for syphilis testing and diagnosis. Neurosyphilis, which is often the result of the progression of untreated syphilis, can be life-threatening and requires intravenous antibiotics. Despite the significant challenge of diagnosing and treating neurosyphilis, there are no standardized testing algorithms available. Typically, the cerebral spinal fluid (CSF) venereal disease research laboratory (VDRL) test is considered the gold standard despite low sensitivity. The CSF fluorescent treponemal antibody absorption (FTA-ABS) test is more sensitive despite being less specific and is often the better testing option. This case illustrates a patient with a clinical presentation strongly suggestive of neurosyphilis despite negative initial lab testing and argues for the emergence of a standardized algorithm to guide clinicians.

Gummatous Neurosyphilis With Transient Worsening of Neurological Symptoms After Treatment Initiation

Cerebral syphilitic gumma is an atypical presentation of neurosyphilis, the clinical manifestations of which depend on the size and location of the lesions. It radiologically presents as enhancing nodular lesion(s) in brain parenchyma. We present a case of a patient with cerebral syphilitic gummas who had worsening neurological symptoms a few hours after initiation of anti-syphilitic antibiotic treatment. We aim to illustrate the clinical and radiological characteristics that might be helpful to clinicians when approaching the challenges they might encounter while treating neurosyphilis.

Three cases of neurosyphilis diagnosed in the 21st century: A case report

In the last decades, it has been considered that syphilis and its complications, including neurological damage, are able to be kept under control with proper epidemiological management. However, socio-economic changes and the problem of antibiotic resistance have brought it back into the focus of clinicians. The present study reports on the cases of three male patients of different ages (28, 76 and 51 years) from different social backgrounds and occupations were provided (first patient, nurse; second patient, pensioner; third patient, navigator); they were confirmed to have neurosyphilis, clinically, paraclinically and by imaging. The complications that may occur in the evolution of the disease but also the beneficial effects of targeted, antisyphilitic and symptomatic therapy were outlined. The purpose of the present study was to highlight issues of major importance regarding neurosyphilis, particularly for neurologists, for whom diagnosis may be challenging. It is key for the neurologist to understand the clinical manifestations and limitations of current diagnostic tests. It is important to consider that a positive rapid plasma reagin test result without confirmation of the presence of Treponema pallidum antibodies in the cerebrospinal fluid may represent a false-positive screening test.

Aberrant gray matter structure in neurosyphilis without conventional MRI abnormality: a pilot study with voxel and surface-based morphology

Background

The underlying mechanism of neurosyphilis was not fully understood.

Purpose

To assess gray matter (GM) microstructure in patients with early-stage neurosyphilis without overt conventional magnetic resonance imaging (MRI) abnormality using voxel-based morphometry (VBM) and surface-based morphometry (SBM) analyses.

Material and Methods

Three-dimensional high-resolution T1-weighted imaging data from 19 individuals with neurosyphilis and 19 healthy controls were analyzed. A battery of neuropsychological tests was performed before each MRI examination. The differences of GM volume and cerebral cortical morphological data between the two groups were compared. The correlations between MRI metrics and neuropsychology/laboratory tests in the patient group were investigated.

Results

Regional decreased GM volumes in patients with neurosyphilis were found in the left frontal cortices (Rolandic operculum, middle frontal, and precentral) and bilateral temporal/occipital cortices (bilateral middle temporal, left lingual, and right middle occipital) ( P < 0.05, FDR correction). SBM analysis showed significant cortical thickness reduction in the right medial orbitofrontal lobe, and reduced gyrification index in the left insula in patients with neurosyphilis ( P < 0.05, FDR correction). Additionally, in the patient group, the GM volume in the middle frontal gyrus, the cortical thickness of right medial orbitofrontal lobe, and the gyrification index in the left insula were negatively correlated to the number connection test-A scores. The gyrification index was also negatively correlated to cerebrospinal fluid white blood cell count.

Conclusion

Early-stage neurosyphilis without conventional MRI abnormality presented regional GM volume reduction and cortical morphological changes, which might be related to cognitive impairment and intra-cranial infection. VBM and SBM analyses might be useful for understanding the underlying neural trait of neurosyphilis.

Gut Microbiota Alternation in Disease Progression of Neurosyphilis

Background

The gut microbiota plays an important role in the development of neurological disorders such as Parkinson's disease and Alzheimer's disease. However, studies on the gut microbiota of patients with neurosyphilis (NS) were rarely reported.

Methods

In this study, we collected fecal samples from 62 syphilis patients, including 39 with NS and 23 with non-NS. Among the NS patients, 18 were general paresis (GP). The white blood cell counts, protein concentrations, and Venereal Disease Research Laboratory test positive rates of cerebrospinal fluid from patients in NS or GP group were significantly higher than those from patients in non-NS group. 16S ribosomal RNA sequencing results revealed that the alpha and beta diversities of the gut microbiota were similar between NS and non-NS patients or GP and non-NS patients.

Results

Linear discriminant analysis with effect size (LEfSe) analysis showed that some taxa, such as Coprobacter, were increased in both NS group and GP group, compared with non-NS group. Besides, the clade of Akkermansia was also overrepresented in GP Patients. Meanwhile, some taxa such as Clostridia_UCG-014 and SC-I-84 were underrepresented in NS patients. The abundances of class Bacilli and genus Alloprevotella were decreased in GP patients. Among them, the abundances of some taxa such as Coprobacter and Akkermansia have been reported to be associated with other neuropsychiatric disorders.

Conclusion

Our findings suggest that the alternation of the gut microbiota in NS patients may contribute to the course of NS, which will deepen our understanding of NS.

Ceftriaxone compared with penicillin G for the treatment of neurosyphilis: study protocol for a multicenter randomized controlled trial

BACKGROUND

Neurosyphilis may cause irreversible neurological sequelae. First-line treatment consists of penicillin G, with ceftriaxone being an alternative treatment in patients allergic to penicillin. The lack of clinical data comparing the efficacy of these two drugs indicated the need for comparative clinical trials to improve national treatment guidelines in China.

METHODS/DESIGN

In this multicenter randomized controlled clinical trial, 290 patients newly diagnosed with neurosyphilis will be randomized 1:1 to treatment with aqueous crystalline penicillin G (ACPG) or ceftriaxone. Patients will be treated with standard regimens of ACPG or ceftriaxone according to Chinese National Guidelines and will be followed up for 12 months. All clinical parameters will be assessed at baseline and at follow-up 3, 6, 9, and 12 months later. The primary outcomes will include cerebrospinal fluid (CSF) white blood cell (WBC) count, serological efficacy, and clinical efficacy. The secondary outcomes will include CSF protein concentrations, Mini-Mental State Examination (MMSE) scores, imaging results, recurrence, and time to recovery from neurosyphilis. Adverse events will be monitored and recorded during the trial.

DISCUSSION

This trial will provide clinical data to determine whether ceftriaxone is non inferior to ACPG in treating neurosyphilis and will provide evidence for the improvement of treatment guidelines.

TRIAL REGISTRATION

Chinese Clinical Trial Registry ChiCTR2100047164. Registered on 9 June 2021 and updated on 23 November 2021.

Locked-in Syndrome Due to Meningovascular Syphilis: A Case Report and Literature Review

We herein report a 46-year-old man presenting with locked-in syndrome secondary to meningovascular syphilis. Brain magnetic resonance imaging (MRI) demonstrated multiple acute infarctions in the left ventromedial pons, right basis pontis, and left basal ganglia. His locked-in syndrome was hypothesized to have been caused by thrombosis of the small paramedian branches of the basilar artery due to syphilitic arteritis. This is a unique case of bilateral ventromedial pontine infarction caused by meningovascular syphilis that presented as locked-in syndrome. Meningovascular syphilis should be included in the differential diagnosis of uncommon stroke, particularly in young men.

Neurosyphilis in China: A Systematic Review of Cases From 2009-2021

Considered the increased threaten of neurosyphilis in China, a review on cases reported in the literature to describe the clinical epidemiological characteristics of neurosyphilis cases, may be beneficial to the early detection and management strategies of neurosyphilis for clinicians. We searched the literature on Chinese neurosyphilis cases published from January 1, 2009 to December 31, 2021, described their clinical epidemiological characteristics and calculated the prevalence of neurosyphilis amongst other associated diseases, according to the individual study criteria. A total of 284 studies including 7,486 neurosyphilis cases were included. No meta-analysis was performed due to the heterogeneity of the data. Among 149 case reports and 93 retrospective case series studies, the main clinical manifestation of 3,507 neurosyphilis cases was cerebral parenchymal syphilis (57.3%), followed by asymptomatic neurosyphilis (16.7%), meningovascular syphilis (13.6%), meningitis syphilis (7.7%) and ocular syphilis (2.8%), etc. In addition, the initial diagnosis was incorrect in 53.2% patients, and the most frequent misdiagnoses were mental disorders (31.0%), stroke (15.9%), cognitive impairment (9.0%), etc. The positive or abnormal rates of cerebrospinal fluid non-treponemal and treponemal tests, white blood cell counts and protein concentrations were 74.2%, 96.2%, 61.5%, and 60.9%, respectively. Aqueous penicillin was the first choice for treatment in 88.3% cases, and 81.7% and 50.0% patients had response in the improvement of symptoms and serological effective in CSF, respectively. Among 26 studies on neurosyphilis patients amongst other associated diseases, the prevalence of neurosyphilis amongst central nervous system infectious diseases, syphilis-associated neurological symptoms, serofast status, coinfected with human immunodeficiency virus were 10.6%-30.1%, 23.2%-35.5%, 9.8%-56.1%, and 8.9%, respectively. In summary, the lack of early detection of neurosyphilis cases remains a clinical challenge. The high rate of misdiagnosis and high prevalence of neurosyphilis amongst associated diseases strongly remind clinicians to focus on the early detection among suspected cases. Besides, the standard treatment regimen and long-term follow-up, which complied with guideline should be provided. Further prospective studies are urgent to better delineate the clinical epidemiological characteristics of neurosyphilis in China.

Homicide and Dementia: A Systematic Review

BACKGROUND

Homicide by older offenders is rare and devastating. It likely occurs due to a complex interaction of personal, social, and environmental factors. Dementia is a progressive neurological condition which may amplify behavioural disturbances such as aggression. This systematic review aims to evaluate the factors associated with homicide committed by people with dementia in order to inform clinical practice.

SUMMARY

MEDLINE, PsychINFO, Embase, and PubMed databases were searched in accordance with PRISMA guidelines for empirical studies examining the characteristics and circumstances of people with dementia who committed homicides. Data on factors associated with the homicide were extracted and the quality of each study rated using standardized criteria. A total of 499 papers were screened and thirteen studies met the inclusion criteria. Study design included case reports (seven studies), case series (four studies), and two retrospective cohort studies, indicative of low levels of evidence. Sample sizes were 1-70. Study findings were predominantly descriptive. Quality ratings ranged from 50 to 100%. Factors associated with disinhibition such as dysexecutive syndrome, alcohol use, and delirium may predispose to severe impulsive aggression. Psychosis and personality pathology appeared to influence targeted assaults resulting in homicide by people with dementia. Victim vulnerability was also a key element.

KEY MESSAGES

The current evidence examining risk factors for homicide committed by people with dementia is limited. However, there are common characteristics reported in these descriptive studies including psychiatric factors and cognitive states causing disinhibition. Recommendations for clinical practice include early assessment of older people with dementia and changed behaviours to allow management of comorbidities and reversible risk factors, alongside education, and advice to carers (who may be targets of aggression). Specialized geriatric forensic psychiatry services and care settings should be developed.

Immune Privilege Furnishes a Niche for Latent Infection

The microenvironment of the CNS (eye and brain) is fertile ground for infection if the barriers are breached. The result of pathogen invasion is often devastating destruction of tissues. In the eye, inflammation is broadly classified either as "infectious" (i.e. caused by infection) or "non-infectious". However, increasingly, forms of intraocular inflammation (IOI), which clinically appear to be "non-infectious" turn out to be initiated by infectious agents, suggesting that pathogens have been retained in latent or persistent form within ocular tissues and have reactivated to cause overt disease. A similar pathogenesis applies to latent infections in the brain. Not all CNS tissues provide an equally protective niche while different pathogens escape detection using different strategies. This review summarises how immune privilege (IP) in the CNS may be permissive for latent infection and allow the eye and the brain to act as a reservoir of pathogens which often remain undetected for the lifetime of the host but in states of immune deficiency may be activated to cause sight- and life-threatening inflammation.

Multiple Spinal Syphilitic Gummas Diagnosed by Postoperative Histopathology and Antibiotic Responsiveness: A Case Report

Neurosyphilis is an infection of the central nervous system by Treponema pallidum. Gummatous neurosyphilis, especially spinal syphilitic gumma, is an exceedingly rare manifestation and may be misdiagnosed as other tumors due to its rarity. A 42-year-old man with a medical history of treatment for syphilis presented with rapidly progressive leg paralysis, leg sensory disturbance, and bladder and rectal disturbance. Spinal MRI demonstrated an intradural extramedullary lesion strongly compressing the spinal cord at the T6/7 level, which was accompanied with dural tail sign and perilesional meningeal thickening at the T6–T8 levels. Small intradural extramedullary lesions were also detected at the T1 and T8 levels. Serological and cerebrospinal fluid examinations for syphilis were both positive. In the treatment of spinal syphilitic gumma, the decompression of the spinal cord by lesionectomy followed by postoperative antibiotic treatment is considered to be an optimal procedure in patients with rapid progression of neurological deterioration. In the present case, the symptomatic main lesion that was compressing the thoracic cord was excised by surgery and analyzed by histopathological examination, and another small asymptomatic lesion was resolved by postoperative antibiotic treatment. Spinal syphilitic gumma was diagnosed using both histopathological findings of the surgically resected lesion and another residual lesion that was resolved by postoperative antibiotic treatment.

Clinical Reasoning: Longitudinally Extensive Spinal Cord Lesions in a Middle-aged Man

An immunocompetent 47-year-old man presented with a five-month history of progressive lower limb weakness, back pain, sphincter dysfunction, and intermittent fever, suggesting myelopathy in a chronic deteriorating course. A comprehensive analysis comprising of blood tests, neuroimaging, CSF profiling, molecular analysis, and histopathology was performed. Notably, enhanced spinal cord MRI revealed longitudinally extensive intradural-extramedullary lesions involving the cervical, thoracic, and lumbosacral spinal cord, with homogeneous enhancement and spinal cord compression. Serum TPHA and RPR tests were positive. CSF profiling showed pleocytosis, significant protein elevations, hypoglycorrhachia, and positive TPHA test. 18F-FDG-PET/CT indicated slightly increased intraspinal FDG uptake. Spinal cord biopsy further showed small round blue cells in poorly differentiated tissues. Immunostaining was positive for NKX2.2, CD56, CD99, Synaptophysin, and Ki67 (50%). Molecular analysis detected a novel MALAT-CYSLTR1 fusion protein and variants in oncogenic genes including PTCH1, TERT, CREBBP, SPEN, and STK11 The diagnosis of intraspinal extraosseous Ewing's sarcoma (ES) was confirmed. Briefly, our case details the diagnosis of a patient with intradural-extramedullary ES and highlights the value of spinal cord biopsy in progressive myelopathy of unknown causes.

Regional Cerebral Blood Flow Abnormalities in Neurosyphilis: A Pilot SPECT Study

Objective: Clinical and radiological findings on neurosyphilis are fairly non-specific and there is a paucity of functional neuroimaging studies on neurosyphilis other than case reports and case series. The purpose of this study was to investigate brain perfusion abnormalities in patients with neurosyphilis. Methods: Four HIV-negative neurosyphilis patients and 4 healthy controls underwent clinical evaluation, brain technetium-99m ethyl cysteinate dimer (99mTc-ECD) single-photon emission computed tomography (SPECT) imaging, and neuropsychological assessments which included the Mini-Mental State Examination (MMSE), Clinical Dementia Rating (CDR), Clinical Dementia Rating-Sum of Boxes (CDR-SOB), and Global Deterioration Scale (GDS). Voxel-wise differences in regional cerebral blood flow were compared between the two groups. Results: Neuropsychological test results indicated cognitive impairment in all patients. SPECT analysis revealed multifocal hypoperfusion predominantly in the frontal, insular, and posterior cingulate regions in neurosyphilis patients compared with healthy controls (family-wise error corrected p < 0.05). Conclusions: Together with previous findings, our results suggest that the hypoperfusion in the frontal, insular, and posterior cingulate regions may reflect cognitive impairments observed in neurosyphilis patients. Further studies with larger samples are needed to confirm our findings.

Predicting asymptomatic neurosyphilis using peripheral blood indicators

BACKGROUND

The high misdiagnosis rate of asymptomatic neurosyphilis (ANS) has long challenged infectious disease clinicians. We aim to develop a model for diagnosing ANS in asymptomatic syphilis (AS) patients without CSF indicators.

RESULTS

277 AS patients with HIV-negative and underwent lumbar puncture were enrolled in this horizontal study.The area under the curve for predicting ANS by CSF leukocytes and protein was 0.643 and 0.675 [95% CI, 0.583-0.699VS.0.616-0.729]. Through LRM, the AUC increased to 0.806 [95% CI, 0.732-0.832], and the Youden's index was 0.430. If the score is ≤ 0.159, ANS can be excluded with a predictive value of 92.9%; we can identify ANS while the score is over 0.819, with a predictive value of 91.7% and a specificity of 99.25%. This study showed that the LRM can diagnose ANS in AS patients effectively.

CONCLUSION

Given a large number of misdiagnosis ANS patients and CSF results' insufficiency, the model is more practical. Our research will help clinicians track suspected syphilis, especially those who cannot accept the CSF test.

Neurosyphilis, A True Chameleon of Neurology

Background:

Neurosyphilis (NS) is a rarely encountered scenario today. Manifestations are heterogeneous, and their characteristics have changed in the antibiotic era. A differential diagnosis of NS is not commonly thought of even with relevant clinical-radiological features, as it mimics many common neurological syndromes.

Objectives:

To study the manifestations of NS in the present era and the process of diagnosis.

Method:

The data of ten patients with NS was collected and analyzed. Their background data, clinical features, investigations, the process of reaching the diagnosis, management and outcomes were recorded.

Observations and Results:

The manifestations of NS in our cohort included six patients with cognitive decline/encephalopathy and one each with meningitis with cranial nerve palsies, cerebellar ataxia, myelitis and asymptomatic NS. The presence of Argyll Robertson pupil helped to clinch diagnosis in one patient. Treponemal tests were ordered in two patients only after alternative etiologies were looked at, to begin with, whereas in six patients treponemal test was requested as a part of standard workup for dementia/ataxia.

Conclusions:

NS dementia and behavior changes are mistaken for degenerative, vascular, nutritional causes, autoimmune encephalitis or prion disease. Meningitis has similarities with infective (tubercular), granulomatous (sarcoidosis, Wegener's), collagen vascular disease and neoplastic meningitis, and myelitis simulates demyelination or nutritional myelopathy (B₁₂ deficiency). Rarely, NS can also present with cerebellar ataxia. Contemplate NS as one of the rare causes for such syndromes, and its early treatment produces good outcomes.

Progressive Stroke Caused by Neurosyphilis With Concentric Enhancement in the Internal Cerebral Artery on High-Resolution Magnetic Resonance Imaging: A Case Report

Background: Neurosyphilis can initially present as a stroke. However, the general management strategy for stroke may not be effective for this condition. Intracranial vessel wall imaging indicating arteritis can help differentiate neurosyphilis from other causes of stroke.

Case presentation: A 59-year-old Chinese woman presented with an acute infarct in the left basal ganglia and multiple stenoses in the bilateral middle cerebral arteries, anterior cerebral artery, and basilar artery, which aggravated twice, despite antiplatelet treatment. High-resolution magnetic resonance imaging (HR-MRI) suggested concentric enhancement in the left middle cerebral artery. Treponema pallidum test results were positive, suggesting neurosyphilis.

Conclusions: HR-MRI provides valuable information regarding arteritis, which is helpful in differentiating neurosyphilis from other causes of stroke. Antiplatelet medication should be used judiciously for neurosyphilis-related stroke.

The challenge of diagnosis and treatment of neurosyphilis in China: results from a nationwide survey

Background The uncertainty of how neurosyphilis is diagnosed and treated in clinical settings led us to investigate whether this serious manifestation of syphilis infection is properly managed in China.

METHODS

This national cross-sectional study of the diagnosis and treatment of neurosyphilis included 1392 clinicians at 398 hospitals located in 116 cities in China.

RESULTS

Of 398 hospitals, 244 (61.3%) failed to perform diagnostic laboratory tests and 181 (45.5%) failed to provide recommended treatment for neurosyphilis. Of 1392 clinicians, 536 (38.5%) had previously diagnosed patients with neurosyphilis, but 419 (78.2%) of the latter provided diagnoses that did not meet the criteria set by national guidelines. Of the 485 clinicians who had previously treated patients with neurosyphilis, 280 (57.7%) failed to follow national guidelines for treatment. Analysis indicated that clinicians working in North China (adjusted odds ratio (aOR), 4.24; 95% confidence interval (CI), 1.65-10.88), tertiary hospitals (aOR, 3.23; 95% CI, 1.63-6.41), and hospitals specialising in sexually transmitted infections (aOR, 2.49; 95% CI, 1.24-4.99) were more likely to follow national guidelines for neurosyphilis treatment.

CONCLUSION

Lack of knowledge in disease management poses a great obstacle to prevent the serious consequences of neurosyphilis in Chinese patients. More effective measures are urgently needed to improve this suboptimal situation.

Syphilitic Spinal Disease: An Old Nemesis Revisited. A Case Series and Review of Literature

ABSTRACT

Syphilitic spinal disease is a rare condition caused by the spirochete Treponema pallidum, either from direct spirochete involvement of the cord or as a consequence of indirect spirochete involvement of the meninges, blood vessels, or the vertebral column. After the introduction of penicillin therapy in the 1940s, it has become an increasingly rare condition. We report 3 challenging cases of syphilitic spinal disease presenting as myelopathy-1 with an extra-axial gumma of tertiary syphilis causing cord compression and 2 with tabes dorsalis complicated by tabetic spinal neuroarthropathy-each presenting a diagnostic dilemma to their treating physicians. We also review the literature for updates on modern investigative modalities and discuss pitfalls physicians need to avoid to arrive at the diagnosis.

Syphilitic meningomyelitis misdiagnosed as spinal cord tumor: Case and review

Context: Syphilitic meningomyelitis is a rare manifestation of neurosyphilis, not well described in the literature.Methods: We reported a rare case of a 29-year-old female with syphilitic meningomyelitis. Her clinical manifestations and imaging findings were discussed with the related literatures reviewed.Results: The patient presented with progressive bilateral lower extremities numbness and weakness for months. Laboratory tests revealed positive serum Treponema pallidum Hemagglutinin Test (TPHA) and rapid plasma reagin test (RPR). The cerebral spinal fluid (CSF) was positive with TPHA but negative for RPR with lymphocytic pleocytosis and elevated protein. Spinal MRI showed swelling and high-signal intensity of thoracic spinal cord except T6-7 level with associated gadolinium enhancement ("flip-flop sign") and peripheral strip-like enhancement on T1WI ("candle guttering appearance"). She was initially diagnosed as spinal cord tumor due to the chronic clinical onset and cord swelling with central enhancement found on thoracic MRI. After dramatic clinical and radiographic improvement with dexamethosone and serological tests of syphilis, she was diagnosed as probable syphilitic meningomyelitis. Till now, there are 12 cases of syphilitic myelitis reported with spinal cord MR images. Thoracic cord is the predominant involved segment (10/12), "candle guttering appearance" is the most common enhancing characteristics of the lesion (7/12), "flip-flop sign" may be seen in the stage with significant inflammation (3/12).Conclusion: Syphilitic meningomyelitis can occur at early or late stage of syphilis, the onset may be acute, subacute or chronic. The imaging findings suggested focal inflammation of the spinal cord. Prognosis is relatively good after proper treatment.

Infections of the Spine and Spinal Cord

PURPOSE OF REVIEW

Infections of the spine and spinal cord are associated with a high risk of morbidity and mortality and, therefore, require prompt clinical recognition, efficient diagnostic evaluation, and interdisciplinary treatment. This article reviews the pathophysiology, epidemiology, clinical manifestations, diagnosis, and treatment of infections of the spine and spinal cord to help practicing clinicians recognize, evaluate, and manage patients with such infections.

RECENT FINDINGS

Aging of the population, increasing use of immunosuppressive medications, and other factors have contributed to increasing rates of spinal infections. Although the most common agents responsible for spinal infections remain bacteria and viruses, fungal infections occur in individuals who are immunocompromised, and parasitic infections are common in endemic regions, but patterns are in evolution with migration and climate change. Recent outbreaks of acute flaccid myelitis in children have been associated with enteroviruses A71 and D68.

SUMMARY

Infections of the spine and spinal cord can be challenging to diagnose, requiring a thorough history and neurologic examination, laboratory studies of serum and CSF, neuroimaging (particularly MRI), and, in some instances, biopsy, to establish a diagnosis and treatment regimen. Interdisciplinary management including collaboration with experts in internal medicine, infectious disease, and neurosurgery is important to improve clinical outcomes.

Neurosyphilis Surveillance: Exploring the Use of Multiple Data Sources to Better Understand Morbidity in California

ABSTRACT

Accurate reporting of neurosyphilis diagnoses is important to quantify and monitor severe outcomes associated with infection of Treponemal pallidum. This analysis compared the demographic distribution of neurosyphilis diagnoses in sexually transmitted disease surveillance data with administrative hospital data in the California Project Area from 2016 to 2018. Although neurosyphilis morbidity was similar, significant differences were noted by sex, age group, race/ethnicity, and region. Both sexually transmitted disease surveillance and administrative hospital data may be imperfect systems to understand the true morbidity of neurosyphilis.

Case Report: Microglia Composition and Immune Response in an Immunocompetent Patient With an Intracranial Syphilitic Gumma

The pathogenesis of intracranial syphilitic gummas remains poorly understood. Microglia are generally considered to be the main cell type of the innate immune system in the brain. Determination of the composition of infiltrating microglia of patients with typical intracranial syphilitic gummas may contribute to the understanding of the pathological process. We report a case of an intracranial syphilitic gumma who presented with right upper limb weakness. The histological analysis showed the presence of Treponema pallidum and infiltration with histiocytes. Immunostaining indicated that cells were predominantly the M2a and M2c, which were Arg-1⁺ and IL-10⁺. These findings suggest that there is an increased number of M2a/M2c microglia in intracranial syphilitic gummas, which may be part of the immune escape mechanisms triggered by Treponema pallidum.

Identification of the factors associated with post-treatment asymptomatic neurosyphilis in HIV-negative patients with serological non-response syphilis: a retrospective study

Some syphilis patients do not exhibit an appropriate serological response after treatment despite the absence of any clinical evidence of treatment failure or reinfection. This condition is called "serofast syphilis" or "serological non-response syphilis." This study explored the incidence of asymptomatic neurosyphilis (ANS) and related factors in 324 asymptomatic patients with serological non-response syphilis. We analyzed descriptive statistics stratified by the presence of asymptomatic neurosyphilis for the basic characteristics of samples. Bivariate analysis was conducted to assess correlations between outcomes and potential predictors. Variables significant in the bivariate analysis (p<0.1) were entered into multivariable logistic regression models. All p-values were two-sided with a significance threshold of p<0.05. The results indicated that 89 of 324 patients had ANS (incidence of 27.5%), and the greatest risk factors were a < fourfold decrease in serum rapid plasma reagin (RPR) titers after treatment and current serum RPR titers >1:32. Our findings suggest that ANS is common among syphilis patients, and patients with a fourfold decrease in serum RPR titers after treatment and current serum RPR titers >1:32 are more likely to develop ANS.

Neurosyphilis revealed by compressive cervical spine syphilitic gumma: a case report

INTRODUCTION

Neurosyphilis is a sexually transmitted disease secondary to the invasion of the central nervous system by the Treponema pallidum. The spinal syphilitic gumma is rare.

CASE PRESENTATION

We report a case of extradural cervical spinal syphilitic gumma revealed by spinal cord compression in a 58-year-old male. The epidural lesion was removed via a posterior approach. Histological examination revealed syphilis. Syphilis serologies were positive. Brain MRI showed an associated cerebro-meningeal syphilitic gumma. Antibiotic regime based on aqueous penicillin G was introduced for 14 days.

DISCUSSION

Currently, there is an increase in the frequency of syphilis and changes in its clinical manifestations. Neurosyphilis can take atypical forms. Spinal syphilitic gumma is a rare manifestation and its association with cerebral involvement is exceptional. Diagnosis is based on serologies in the blood and cerebrospinal fluid. The place of imagery, especially magnetic resonance imaging, is essential. Neurosyphilis should be discussed as a possible differential diagnosis in evaluation of spinal and cerebral lesions.

Neuro-Ophthalmic Manifestations of HIV Infection

Purpose: To review the broad spectrum of clinical neuro-ophthalmic presentations associated with human immunodeficiency virus (HIV) infection. Methods: Critical review of the literature regarding neuro-ophthalmic consequences of HIV infection and its sequelae. Results: Neuro-ophthalmological diseases are common in both asymptomatic HIV-positive patients and those who profound immunosuppression with acquired immune deficiency syndrome (AIDS). Neuro-ophthalmic manifestations of HIV infection can involve the afferent or efferent visual pathway. Common clinical presentations include headache, papilledema, chorioretinitis, optic nerve involvement, meningitis, and cranial nerve palsies. Other neuro-ophthalmic manifestations include involvement of the visual pathway in the brain producing visual field defects such as occur in progressive multifocal encephalopathy. Pupil abnormalities have also been reported. Discussion: Neuro-ophthalmic consequences of HIV are important to recognize as it is critical to identify underlying neoplastic or infectious diseases which could be amenable to treatment.

A comparison of nontreponemal tests in cerebrospinal fluid for neurosyphilis diagnosis: equivalent detection of specific antibodies

BACKGROUND

Syphilis is a re-emerging sexually-transmitted infection, caused by the spirochete Treponema pallidum, that may penetrate early into the central nervous system. The venereal disease research laboratory test (VDRL) on the cerebrospinal fluid (CSF) is the most widely used for neurosyphilis diagnosis. We evaluated the performance of two other nontreponemal tests (rapid plasma reagin [RPR] and unheated serum reagin [USR] tests) in comparison with the VDRL in CSF.

METHODS

We analyzed CSF samples from 120 individuals based on VDRL reactivity in the CSF and the clinical picture of neurosyphilis.

RESULTS

High inter-rater reliability was found among all three tests, with equivalent sensitivity and specificity. Intraclass correlation coefficient for absolute agreement was 1 for VDRL versus USR, 0.99 for VDRL versus RPR, and 0.99 for RPR versus USR.

CONCLUSIONS

Rapid plasma reagin and unheated serum reagin tests were identified as excellent alternatives for neurosyphilis diagnosis.

Reversible Dementias

PURPOSE OF REVIEW

This article describes the clinical features that suggest a reversible cause of dementia.

RECENT FINDINGS

Substantial variability exists in the presenting features and clinical course of patients with common neurodegenerative causes of dementia, but the response to available therapies and eventual outcomes are often poor. This realization has influenced the evaluation of patients with dementia, with diagnostic approaches emphasizing routine screening for a short list of potentially modifiable disorders that may exacerbate dementia symptoms or severity but rarely influence long-term outcomes. Although a standard approach to the assessment of dementia is appropriate in the vast majority of cases, neurologists involved in the assessment of patients with dementia must recognize those rare patients with reversible causes of dementia, coordinate additional investigations when required, and ensure expedited access to treatments that may reverse decline and optimize long-term outcomes.

SUMMARY

The potential to improve the outcome of patients with reversible dementias exemplifies the need to recognize these patients in clinical practice. Dedicated efforts to screen for symptoms and signs associated with reversible causes of dementia may improve management and outcomes of these rare patients when encountered in busy clinical practices.

Neurosyphilis complicated with pial arteriovenous fistula: A rare case report

INTRODUCTION

Neurosyphilis is a chronic, infectious disease of the central nervous system. Pial arteriovenous fistulae (PAVF) are rare vascular malformations. Both can cause vascular damage, but it is quite rare for both to present at the same time.

PATIENT CONCERNS

Here we present a 66-year-old man with affective disorder, hypomnesia, and recent convulsions. Magnetic resonance imaging revealed cerebral swelling, hyperintensity in the cortex/subcortex, and multiple lacunar cerebral infarctions. Computed tomography angiography revealed the presence of a pial arteriovenous fistula.

DIAGNOSES

Based on laboratory tests and imaging, diagnoses of neurosyphilis and pial arteriovenous fistula were made.

INTERVENTIONS

Antisyphilis therapy was provided.

OUTCOMES

Symptoms improved and antisyphilis treatment continued as an outpatient. No intracranial hemorrhage was seen 6 months later.

CONCLUSION

Treponema pallidum infection may be related to the formation of PAVF, and may also promote the progression of it; however, further work is required to confirm this.

Neurosyphilis prevalence at a Portuguese stroke unit care

INTRODUCTION

Syphilis is a systemic human disease which is caused by infection with the spirochete Treponema pallidum. It is spread worldwide, and there has recently been an increase in its incidence. Neurosyphilis (NS) can have a variety of presentations; meningovascular NS is a specific affection of the Treponema which occurs in an early stage after the primary infection, causing an inflammatory arteriopathy which may result in an ischemic stroke. As a rare manifestation of syphilis, there are few prevalence and epidemiological studies, and data are almost non-existent. The objective of this study is to analyse the prevalence of meningovascular NS in a stroke unit in a tertiary hospital.

METHODS

A descriptive retrospective study was carried out over a period of 44 months in a stroke unit. All patients admitted had neurological symptoms compatible with a vascular event, and routine blood tests including infectious screening were performed. Those with positive test results for syphilis were identified and proceeded to lumbar puncture to CSF cytochemical analysis and VDRL. NS was categorized as confirmed or probable (using CDC criteria).

RESULTS

A total of 525 patients were admitted, and 62.53% were submitted to a routine screening for syphilis. A total of 309 patients (95.67%) revealed a negative screening; 12 patients (3.72%) had a positive syphilis serology. Among the 12 patients with positive screening, a single case of NS (0.31%) was identified.

CONCLUSION

We observed a low prevalence of NS (0.31%), but this result was surprisingly higher than what was expected in an elderly population.

Qualitative vs. Quantitative Methods in Psychiatric Research: Updated

Since the incipiency of psychiatry as a medical specialty, the "holy grail" has been neuroscience-based diagnostic system and treatment strategies, but this lofty, yet necessary, goal has eluded the greatest minds for centuries. Now, with advances in molecular genetics and resting-state neuroimaging, neuroscience-based diagnosis and treatment are now more possible than ever. However, clinical symptomatology, longitudinal course, and delimitation of illnesses (i.e., phenotypic classification) remain indispensable for responsible, reproducible, and meaningful use of these new methodologies.

Clinical features of syphilitic myelitis with longitudinally extensive myelopathy on spinal magnetic resonance imaging

BACKGROUND

Syphilitic myelitis caused by Treponema pallidum is an extremely rare disease. However, symptomatic neurosyphilis, especially syphilitic myelitis, and its clinical features have been infrequently reported. Only a few cases of syphilitic myelitis have been documented. To the best of our knowledge, there are only 19 reported cases of syphilitic myelitis. However, the clinical features of syphilitic myelitis with longitudinally extensive myelopathy have been still not clear.

AIM

To explore the clinical features of syphilitic myelitis with longitudinally extensive myelopathy on spinal magnetic resonance imaging (MRI).

METHODS

First, we report a patient who suffered from syphilitic myelitis with symptoms of sensory disturbance, with longitudinally extensive myelopathy with "flip-flop sign" on spinal MRI. Second, we performed a literature search to identify other reports (reviews, case reports, or case series) from January 1987 to December 2018, using the PubMed and Web of Science databases with the terms including "syphilis", "neurosyphilis", "syphilitic myelitis", "meningomyelitis", "central nervous system", and "spine". We also summarized the clinical features of syphilitic myelitis with longitudinally extensive myelopathy.

RESULTS

A total of 16 articles of 20 cases were identified. Sixteen patients presented with the onset of sensory disturbance (80%), 15 with paraparesis (75%), and 9 with urinary retention (45%). Eleven patients had a high risk behavior (55%). Five patients had concomitant human immunodeficiency virus infection (25%). Serological data showed that 15 patients had positive venereal disease research laboratory test (VDRL)/treponema pallidum particle agglutination (TPHA), and 17 had positive VDRL/TPHA in cerebrospinal fluid (CSF). Seventeen patients were found to have elevated leukocytosis and protein in CSF. On MRI, 16 patients showed abnormal hyperintensities involved the thoracic spine, 6 involved the cervical spine, and 3 involved both the cervical and thoracic spine. There were 3 patients with the "flip-flop sign". All the patients were treated with penicillin, and 15 patients had a good prognosis.

CONCLUSION

Our case further raises awareness of syphilitic myelitis as an important complication of neurosyphilis due to homosexuality, especially in developing countries such as China.

Antibiotic therapy for adults with neurosyphilis

BACKGROUND

Neurosyphilis is an infection of the central nervous system, caused by Treponema pallidum, a spirochete capable of infecting almost any organ or tissue in the body causing neurological complications due to the infection. This disease is a tertiary manifestation of syphilis. The first-line treatment for neurosyphilis is aqueous crystalline penicillin. However, in cases such as penicillin allergy, other regimes of antibiotic therapy can be used.

OBJECTIVES

To assess the clinical effectiveness and safety of antibiotic therapy for adults with neurosyphilis.

SEARCH METHODS

We searched the Cochrane Library, CENTRAL, MEDLINE, Embase, LILACS, World Health Organization International Clinical Trials Registry Platform and Opengrey up to April 2019. We also searched proceedings of eight congresses to a maximum of 10 years, and we contacted trial authors for additional information.

SELECTION CRITERIA

We included randomised clinical trials that included men and women, regardless of age, with definitive diagnoses of neurosyphilis, including HIV-seropositive patients. We compared any antibiotic regime (concentration, dose, frequency, duration), compared to any other antibiotic regime for the treatment for neurosyphilis in adults.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected eligible trials, extracted data, and evaluated risk of bias. We resolved disagreements by involving a third review author. For dichotomous data (serological cure, clinical cure, adverse events), we presented results as summary risk ratios (RR) with 95% confidence intervals (CI). We assessed the quality of evidence using the GRADE approach.

MAIN RESULTS

We identified one trial, with 36 participants​ diagnosed ​with syphilis and HIV. The participants were mainly men, with a median age of 34 years. This trial, ​funded by a pharmaceutical company, compared ceftriaxone in 18 participants (2 g daily for 10 days), with penicillin G, also in 18 participants (4 million/Units (MU)/intravenous (IV) every 4 hours for 10 days). The trial reported incomplete and inconclusive results. Three of 18 (16%) participants receiving ceftriaxone versus 2 of 18 (11%) receiving penicillin G achieved serological cure (RR 1.50; 95% CI: 0.28 to 7.93; 1 trial, 36 participants very low-quality evidence); and 8 of 18 (44%) participants receiving ceftriaxone versus 2 of 18 (18%) participants receiving penicillin G achieved clinical cure (RR 4.00; 95% CI: 0.98 to 16.30; 1 trial, 36 participants very low-quality evidence). Although more participants who received ceftriaxone achieved serological and clinical cure compared to those who received penicillin G, the evidence from this trial was insufficient to determine whether there was a difference between treatment with ceftriaxone or penicillin G.In this trial, the authors reported what would usually be adverse events as symptoms and signs in the follow-up of participants. Furthermore, this trial did not evaluate recurrence of neurosyphilis, time to recovery nor quality of life. We judged risk of bias in this clinical trial to be unclear for random sequence generation, allocation, ​and blinding of participants, and high for incomplete outcome data, potential conflicts of interest (funding bias), and other bias, due to the lack of a sample size calculation. We rated the quality of evidence as very low.

AUTHORS' CONCLUSIONS

Due to low quality and insufficient evidence, it was not possible to determine whether there was a difference between treatment with ceftriaxone or Penicillin G. Also, the benefits to people without HIV and neurosyphilis are unknown, as is the ceftriaxone safety profile.Therefore, these results should be interpreted with caution. This conclusion does not mean that antibiotics should not be used for treating this clinical entity. This Cochrane Review has identified the need of adequately powered trials, which should be planned according to Standard Protocol Items: Recommendations for Interventional Trials (SPIRIT) recommendations, conducted and reported as recommended by the CONSORT statement. Furthermore, the outcomes should be based on patients' perspectives taking into account Patient-Centered Outcomes Research Institute (PCORI) recommendations.

Diagnosis and management of sensory polyneuropathy

Sensory polyneuropathies, which are caused by dysfunction of peripheral sensory nerve fibers, are a heterogeneous group of disorders that range from the common diabetic neuropathy to the rare sensory neuronopathies. The presenting symptoms, acuity, time course, severity, and subsequent morbidity vary and depend on the type of fiber that is affected and the underlying cause. Damage to small thinly myelinated and unmyelinated nerve fibers results in neuropathic pain, whereas damage to large myelinated sensory afferents results in proprioceptive deficits and ataxia. The causes of these disorders are diverse and include metabolic, toxic, infectious, inflammatory, autoimmune, and genetic conditions. Idiopathic sensory polyneuropathies are common although they should be considered a diagnosis of exclusion. The diagnostic evaluation involves electrophysiologic testing including nerve conduction studies, histopathologic analysis of nerve tissue, serum studies, and sometimes autonomic testing and cerebrospinal fluid analysis. The treatment of these diseases depends on the underlying cause and may include immunotherapy, mitigation of risk factors, symptomatic treatment, and gene therapy, such as the recently developed RNA interference and antisense oligonucleotide therapies for transthyretin familial amyloid polyneuropathy. Many of these disorders have no directed treatment, in which case management remains symptomatic and supportive. More research is needed into the underlying pathophysiology of nerve damage in these polyneuropathies to guide advances in treatment.

Diagnostic tools to tackle infectious causes of encephalitis and meningoencephalitis in immunocompetent adults in Europe

BACKGROUND

Encephalitis and meningoencephalitis imply inflammation of the brain parenchyma, and comprise many diagnostic entities, such as various infections and causes of dysimmunity. The cause remains unknown in around 50% of cases.

OBJECTIVES

To summarize the main infectious causes of encephalitis and meningoencephalitis acquired in Europe, and the diagnostic means to identify them.

SOURCES

PubMed, ECDC and WHO websites, personal experience.

CONTENT

The principal infectious causes of encephalitis and meningoencephalitis acquired in Europe in adults are discussed in this review, with special emphasis on the microbiological and imaging diagnostic approaches. The role of electroencephalography in diagnosing encephalitis is also mentioned. Among infections, viruses are more frequent than other pathogen types, and their epidemiology varies according to geographic area. A few bacteria, such as Listeria monocytogenes and Mycobacterium tuberculosis, are also to be considered. In contrast, parasites and fungi are rare encephalitis causes in Europe.

IMPLICATIONS

Identifying the causative pathogen of infectious encephalitis and meningoencephalitis is complex because of the variety of pathogens, the epidemiology of which is determined by geography and environmental factors. Furthermore, despite extensive microbiological testing, many cases of encephalitis remain of unknown origin. Brain magnetic resonance imaging and electroencephalography are useful complementary diagnostic tools, and newer unbiased sequencing technologies might help to fill in the diagnostic gap.

Nodulo-ulcerative and erythrodermic secondary syphilis in human immunodeficiency virus-infected individuals

Syphilis and human immunodeficiency virus (HIV) infections are both transmitted sexually. Co-infection of HIV and syphilis alters the course of both diseases. Clinical presentation of syphilis in patients of HIV may be atypical. HIV-infected individuals are at risk of developing lues maligna, which is characterized by nodulo-ulcerative lesions associated with severe constitutional symptoms. Erythroderma secondary to generalized papulo-squamous lesions of secondary syphilis is also uncommon. Here we report two cases of atypical presentations of secondary syphilis in HIV-positive patients.

Neurosyphilis and ocular syphilis clinical and cerebrospinal fluid characteristics: a case series

BACKGROUND

During the first decade of this century, a significant increase in the incidence of syphilis was documented.

OBJECTIVE

To study clinical and laboratory characteristics of central nervous system and ocular syphilis.

METHODS

A retrospective case series of 13 patients with a clinical and laboratory diagnosis of neurosyphilis and/or ocular syphilis who had been admitted to the Neurology and Neuro-ophthalmology Service of the Hospital de Clínicas, Federal University of Paraná.

RESULTS

Nine patients had a diagnosis of neurosyphilis and two of them also had ocular syphilis. Four patients had a diagnosis of ocular syphilis alone. Among the patients with a diagnosis of neurosyphilis, six had symptomatic syphilitic meningitis, of whom one manifested as cranial nerve palsy alone, one as cranial nerve palsy plus ocular syphilis, two as transverse myelitis (syphilitic meningomyelitis), one as meningitis worsening the patient's myasthenia gravis symptoms and one as meningitis plus ocular syphilis. Additionally, we diagnosed three patients with meningovascular neurosyphilis. In the univariate analysis, patients without ocular syphilis showed greater levels of total protein and white blood cells in the cerebrospinal fluid than patients with ocular syphilis.

CONCLUSION

This Brazilian case series of patients with neurosyphilis and ocular syphilis highlights the wide variability of this disease. A high degree of diagnostic suspicion is necessary when facing neurological and ocular symptoms for rapid diagnosis and appropriate management of patients.

HIV and spinal cord disease

The epidemiology of spinal cord disease in human immunodeficiency virus (HIV) infection is largely unknown due to a paucity of data since combination antiretroviral therapy (cART). HIV mediates spinal cord injury indirectly, by immune modulation, degeneration, or associated infections and neoplasms. The pathologies vary and range from cytotoxic necrosis to demyelination and vasculitis. Control of HIV determines the differential for all neurologic presentations in infected individuals. Primary HIV-associated acute transverse myelitis, an acute inflammatory condition with pathologic similarities to HIV encephalitis, arises in early infection and at seroconversion. In contrast, HIV vacuolar myelopathy and opportunistic infections predominate in uncontrolled disease. There is systemic immune dysregulation as early as primary infection due to initial depletion of gut-associated lymphoid tissue CD4 cells and allowance of microbial translocation across the gut that never fully recovers throughout the course of HIV infection, regardless of how well controlled. The subsequent proinflammatory state may contribute to spinal cord diseases observed even after cART initiation. This chapter will highlight an array of spinal cord pathologies classified by stage of HIV infection and immune status.

Prevalence and association of syphilis reactivity in an Asian memory clinic population

Data on the association between syphilis reactivity and dementia in memory clinic patients are scarce. We studied the prevalence of syphilis reactivity and investigated its association with dementia and markers of cerebrovascular disease (CeVD) and neurodegeneration. Data on age, gender, education, brain computed tomography scan findings and syphilis reactivity were obtained from patients who attended the National University Hospital memory clinics (February 2006-February 2016) and subjects from the community. Binary logistic regression models were used to investigate associations between syphilis reactivity and dementia, CeVD and neurodegeneration, and odds ratios (ORs) with 95% confidence intervals (CIs) were calculated. Of 1271 memory clinic patients eligible for the study, 57 (4.5%) were syphilis reactive, with the rate of syphilis reactivity higher in demented (44/745; 5.9%) compared to non-demented (13/526; 2.5%) patients ( p = 0.004) and non-demented community-based (21/872; 2.4%) subjects ( p < 0.001). Binary logistic regression showed a significant association between syphilis reactivity and dementia in memory clinic patients independent of demographic factors (odds ratio: 2.06; 95% CI: 1.02-4.17, p = 0.044). A significant association between syphilis reactivity and dementia was found in memory clinic patients. The mechanism of this association requires further research and may involve neuroinflammation.