Ocular and neurosyphilis: epidemiology and approach to management

Characteristic Profiling of Soluble Factors in the Cerebrospinal Fluid of Patients With Neurosyphilis

BACKGROUND

Soluble inflammatory factors in the cerebrospinal fluid (CSF) of patients with neurosyphilis have been investigated with low-throughput technology. This study aimed to illustrate the characteristics of soluble factor profiles in CSF of patients with neurosyphilis.

METHODS

We measured the concentrations of 45 cytokines, chemokines, and growth factors in CSF from 112 untreated syphilis cases, including latent syphilis (LS), asymptomatic neurosyphilis (ANS), meningeal neurosyphilis (MNS), meningovascular neurosyphilis (MVNS), paralytic dementia (PD), and ocular syphilis (OS).

RESULTS

Thirty-three differentially expressed soluble factors (DeSFs) were categorized into 3 clusters. DeSF scores of clusters 1 and 2 (DeSFS1 and DeSFS2) were positively correlated with elevated neopterin and neurofilament light subunit (NF-L) concentration, respectively. DeSF scores of cluster 3 were positively correlated with white blood cells, protein, NF-L, and neopterin. Patients with LS, ANS, and OS exhibited an overall lower abundance of DeSFs. Patients with PD exhibited significantly increased levels of clusters 1 and 3, and the highest total DeSF score, whereas patients with MNS and MVNS showed enhanced levels of cluster 2. Receiver operating characteristic analysis revealed that DeSFS1 effectively discriminated PD, and DeSFS2 discriminated MNS/MVNS with high accuracy.

CONCLUSIONS

Patients with neurosyphilis at different stages have distinctive patterns of soluble factors in CSF, which are correlated with immune status and neuronal damage.

An Incidental Diagnosis of Neurosyphilis: A Case Report

Neurosyphilis, a rare manifestation of Treponema pallidum spreading into the central nervous system, is a critical differential diagnosis due to its potentially severe neurologic effects if left untreated. We present a case of a 37-year-old woman who complained of bilateral vision loss and headaches originally concerning for idiopathic intracranial hypertension and uncontrolled diabetes. Comprehensive evaluations eventually led to a neurosyphilis diagnosis. Ophthalmologic examination revealed multifactorial visual symptoms with diabetic retinopathy contributing alongside neurosyphilis. Treatment was started promptly at the time of diagnosis and resulted in improvement in visual symptoms. This case emphasizes the importance of syphilis screening in appropriate age ranges, even in low-prevalence areas. Recognition of neurosyphilis as a potential diagnosis can impact patient outcomes and highlights the need for continued vigilance to identify the disease.

Identification of potential biomarkers for diagnosis of syphilis from the cerebrospinal fluid based on untargeted metabolomic analysis

The infection rate of syphilis continues to rise globally, and the difficulty in diagnosis of neurosyphilis promptly needs to be resolved. More specific and sensitive diagnostic markers for latent syphilis and neurosyphilis should be found. Here the metabolic profiles of 88 cerebrospinal fluid samples from syphilis patients and controls were analyzed by LC/MS-based untargeted metabolomics. In total, 272 metabolites based on 3937 features obtained in ESI- mode and 252 metabolites based on 3799 features in ESI+ mode were identified. The experimental process was evaluated by principal component analysis, partial least squares discriminant analysis, and hierarchical cluster analysis. A clear separation between latent syphilis and neurosyphilis was found. Levels of lipid and linoleic acid metabolites, such as 9-oxo-octadecadienoic acid and 9,10,13-trihydroxyoctadecenoic acid, were increased in syphilis patients. In patients with neurosyphilis, significant changes in levels of 5-hydroxy-L-tryptophan (5-HTP) and acetyl-N-formyl-5-methoxykynurenamine (AFMK) in the tryptophan-kynurenine pathway were also detected. Only one metabolite, theophylline, differed significantly between symptomatic and asymptomatic neurosyphilis patients. Additionally, KEGG analysis revealed significant enrichment of tryptophan metabolism pathways, indicating a high correlation between tryptophan metabolism and syphilis symptoms. Levels of linoleic acid metabolites, 5-HTP, AFMK and theophylline were significantly altered in different patients. The role of these differential metabolites in the development of syphilis is worthy of further exploration. Our results may promote the development of biomarkers for diagnosis of latent syphilis from neurosyphilis, and for that of asymptomatic neurosyphilis from symptomatic neurosyphilis in the future.

An Updated Review of Recent Advances in Neurosyphilis

Neurosyphilis is caused by Treponema pallidum invading the central nervous system, of which the incidence is increasing worldwide. Due to its variable clinical manifestations, diagnosis of neurosyphilis remains challenging, especially the asymptomatic form. This review focuses on recent advances in neurosyphilis, including epidemiology, clinical manifestations, laboratory findings, comorbidities, diagnosis, treatment, prognosis, and basic research. The expansion of men who have sex with men and the infection of human immunodeficiency virus mainly accounted for the increasing incidence of neurosyphilis. The rate of some historically described forms of neurosyphilis in the pre-antibiotic era declined significantly; atypical features are more prevalent. Neurosyphilis, regarded as a great mimicker for neuro-ophthalmic, audio-vestibular, and psychiatric disorders, often presents concomitantly with other diseases, including metabolic disorders. Studies on long non-coding RNAs, miRNAs, chemokines, and metabolites in peripheral blood and cerebrospinal fluid may facilitate exploring the pathogenesis and identifying novel biomarkers of neurosyphilis. The drug resistance of Treponema pallidum to penicillin has not been reported; ceftriaxone was proposed to be more effective than penicillin, whereas few randomized controlled trials supported this view. This study may pave the way for further research, especially the diagnosis and treatment of neurosyphilis.

Otosyphilis: A Rare Cause of Reversible Hearing Loss in a Teenage Male

A high index of suspicion and a thorough neurotologic examination at the onset of presentation are imperative to generate the diagnosis of otosyphilis. Complete audiologic recovery is rare but possible in approximately 20%-25% of patients after appropriate treatment. We present a case of reversible hearing loss secondary to otosyphilis in a teenage male patient with a new diagnosis of human immunodeficiency virus (HIV). Audiology findings were consistent with mixed hearing loss. Lumbar puncture results were consistent with neurosyphilis. Prompt treatment with a 14-day course of intravenous penicillin led to the complete recovery of hearing. In this case report, the pathophysiology, symptomology, and management of otosyphilis are discussed.

Isolated Cranial Nerve VI Palsy and Neurosyphilis: A Case Report and Review of Related Literature

An isolated cranial nerve VI palsy is a rare initial manifestation of undiagnosed neurosyphilis. A 33-year-old male presented with a one month history of progressive headache and diplopia. Neurologic examination only revealed an isolated abducens palsy on the left. Cranial imaging was unremarkable. Examination of his cerebrospinal fluid revealed lymphocytic predominant leukocytosis and elevated protein. Microbiologic work-up were all negative. Further work-up revealed the patient to be serum Rapid Plasma Reagin and Enzyme Immunoassay reactive. Enzyme-linked immunosorbent assay for Human Immunodeficiency Virus also tested positive. His cerebrospinal fluid was then sent for Rapid Plasma Reagin to confirm the diagnosis of neurosyphilis. He completed 14 days of intravenous penicillin and was eventually discharged with partial resolution of the abducens palsy. We describe the second case of neurosyphilis presenting only with an isolated cranial nerve VI involvement. On further review, ours was the first case documented on an individual who had an undiagnosed Human Immunodeficiency Virus infection. There are various differentials for an isolated cranial neuritis but infectious causes, particularly neurosyphilis, should be considered among young individuals with known risk factors despite their apparently benign medical history.

Chronic pain and infection: mechanisms, causes, conditions, treatments, and controversies

Throughout human history, infection has been the leading cause of morbidity and mortality, with pain being one of the cardinal warning signs. However, in a substantial percentage of cases, pain can persist after resolution of acute illness, manifesting as neuropathic, nociplastic (eg, fibromyalgia, irritable bowel syndrome), or nociceptive pain. Mechanisms by which acute infectious pain becomes chronic are variable and can include immunological phenomena (eg, bystander activation, molecular mimicry), direct microbe invasion, central sensitization from physical or psychological triggers, and complications from treatment. Microbes resulting in a high incidence of chronic pain include bacteria such as the Borrelia species and Mycobacterium leprae, as well as viruses such as HIV, SARS-CoV-2 and herpeses. Emerging evidence also supports an infectious cause in a subset of patients with discogenic low back pain and inflammatory bowel disease. Although antimicrobial treatment might have a role in treating chronic pain states that involve active infectious inflammatory processes, their use in chronic pain conditions resulting from autoimmune mechanisms, central sensitization and irrevocable tissue (eg, arthropathy, vasculitis) or nerve injury, are likely to cause more harm than benefit. This review focuses on the relation between infection and chronic pain, with an emphasis on common viral and bacterial causes.

Neurosyphilis in a suspected case of giant cell arteritis

A 67-year-old man had a few month history of deteriorating visual acuity. He had originally presented to ophthalmology with right-sided visual blurring. This subsequently progressed to involve the left eye. At this point, he was empirically treated with high-dose glucocorticoids, both orally and intravenously, with the suspicion that giant cell arteritis was causing acute visual deterioration of his left eye. Unfortunately, his symptoms did not improve. During an admission to hospital for a pneumonia, he underwent further investigations for this bilateral visual loss. He was diagnosed with left neuroretinitis and right vitritis. A thorough workup revealed positive syphilis serology and cerebrospinal fluid was positive on venereal disease research laboratory testing. He was diagnosed and treated for neurosyphilis with intravenous benzylpenicillin 4 million units 4 hourly for 14 days. His left-sided vision improved but he still suffers from severe visual impairment in his right eye.

Ocular Syphilis Presenting As Non-arteritic Anterior Ischemic Optic Neuropathy

Syphilis is a sexually transmitted disease caused by the spirochetal bacteria Treponema pallidum. It can cross the blood-brain barrier within days of the infection, causing neurosyphilis and ocular syphilis at any stage of the disease. Ocular syphilis can manifest in any part of the eye but usually as posterior uveitis and pan-uveitis or various types of inflammatory or immune-mediated optic neuritis. Misdiagnosing ocular syphilis as a non-infectious disease has been reported even when seen by ophthalmologists due to the wide variety of possible presentations. In this case report, we describe a case of ocular syphilis that presented with a non-arteritic anterior ischemic optic neuropathy (NA-AION), which to our knowledge, has not been described before in the literature.

Ocular syphilis - a case series of four patients

Ocular manifestations of syphilis with visual impairment symptoms may occur already at the stage of secondary syphilis. They may also be the only manifestation of syphilis and mimic other diseases of the eye. Therefore, in all patients with uveitis, optic neuritis, optic atrophy, acute ocular muscle paresis, or loss of visual acuity, syphilis infection should be ruled out, even if the medical history does not initially raise suspicion. Ocular involvement should be treated as neurosyphilis. Delayed diagnosis and inadequate therapy are often associated with irreversible consequences for the affected patient. As with any syphilis infection, HIV infection should be considered and excluded, especially in the case of ocular manifestations.

Ocular syphilis

Syphilis is a sexually transmitted, systemic, inflammatory disease caused by the spirochaete, Treponema pallidum. The natural history of untreated syphilis progresses through four distinct stages: primary, secondary, latent, and tertiary syphilis. Ocular involvement can occur at any stage of syphilis and any part of the eye can be affected. With the exception of syphilitic posterior placoid chorioretinitis, the diverse manifestations of ocular syphilis have few distinct features that can be used to assist in clinical diagnosis. Therefore, ocular syphilis should always be a part of the differential diagnosis of most, if not all, ocular infectious and inflammatory presentations. Specifically, uveitis presentations, high-risk sexual history, illicit drug use history, treatment failure, prior history of syphilis should prompt further diagnostic workup for ocular syphilis. A presumptive diagnosis of ocular syphilis relies on serological testing, both treponemal and nontreponemal tests. All patients with ocular syphilis should have their cerebrospinal fluids tested for the co-existence of neurosyphilis and their blood tested for human immunodeficiency virus co-infection. In the United States, Centers for Disease Control and Prevention recommend that ocular syphilis be managed according to its treatment guidelines for neurosyphilis, with parenteral aqueous crystalline penicillin G the drug of choice. With the timely diagnosis and appropriate treatment, ocular syphilis is curable. However, delayed diagnosis of ocular syphilis may result in long-term visual impairment. Delayed diagnosis occurs because of its diverse presentations mimicking other ocular diseases, and failure of the clinician to order serological testing. With the recent worldwide resurgence of ocular syphilis, clinicians should be familiar with the manifestation, diagnosis, and treatment of ocular syphilis.

Double Trouble: Challenges in the Diagnosis and Management of Ocular Syphilis in HIV-infected Individuals

Syphilis and HIV infection may coexist in the same individual. Ocular syphilis and/or neurosyphilis may develop at any stage of coinfection, with a stronger association between ocular and neurosyphilis in individuals living with HIV, than in HIV-uninfected individuals. The diagnosis of ocular syphilis in HIV-infected and -uninfected patients remains with some controversy due to unspecific clinical manifestations and limited diagnostic tests. Penicillin is the mainstay of treatment of ocular syphilis, but alternative options are warranted. This review describes the epidemiology, pathophysiology, and clinical manifestations, as well as the diagnostic and therapeutic challenges posed by ocular syphilis against the background of HIV coinfection.