Bright New Resources for Syphilis Research: Genetically Encoded Fluorescent Tags for Treponema pallidum and Sf1Ep Cells.

The recently discovered methodologies to cultivate and genetically manipulate Treponema pallidum subsp. pallidum (T. pallidum) have significantly helped syphilis research, allowing the in vitro evaluation of antibiotic efficacy, performance of controlled studies to assess differential treponemal gene expression, and generation of loss-of-function mutants to evaluate the contribution of specific genetic loci to T. pallidum virulence. Building on this progress, we engineered the T. pallidum SS14 strain to express a red-shifted green fluorescent protein (GFP) and Sf1Ep cells to express mCherry and blue fluorescent protein (BFP) for enhanced visualization. These new resources improve microscopy- and cell sorting-based applications for T. pallidum, better capturing the physical interaction between the host and pathogen, among other possibilities. Continued efforts to develop and share new tools and resources are required to help our overall knowledge of T. pallidum biology and syphilis pathogenesis reach that of other bacterial pathogens, including spirochetes.

Genomic Epidemiology of Treponema pallidum and Circulation of Strains With Diminished tprK Antigen Variation Capability in Seattle, 2021-2022.

BACKGROUND: The incidence of syphilis continues to increase in the United States, yet little is known about Treponema pallidum genomic epidemiology within American metropolitan areas. METHODS: We performed whole-genome sequencing and tprK deep sequencing of 28 T. pallidum-containing specimens, collected mostly from remnant Aptima swab specimens from 24 individuals from Seattle Sexual Health Clinic during 2021-2022. RESULTS: All 12 individuals infected with Nichols-lineage strains were men who have sex with men, while a specific SS14 cluster (mean, 0.33 single-nucleotide variant) included 1 man who has sex with women and 5 women. All T. pallidum strains sequenced were azithromycin resistant via 23S ribosomal RNA A2058G mutation. Identical T. pallidum genomic sequences were found in pharyngeal and rectal swab specimens taken concurrently from the same individuals. The tprK sequences were less variable between patient-matched specimens and between epidemiologically linked clusters. We detected a 528-base pair deletion in the tprK donor site locus, eliminating 9 donor sites, in T. pallidum genomes of 3 individuals with secondary syphilis, associated with diminution of TprK diversity. CONCLUSIONS: We developed an end-to-end workflow for public health genomic surveillance of T. pallidum from remnant Aptima swab specimens. tprK sequencing may assist in linking cases beyond routine T. pallidum genome sequencing. T. pallidum strains with deletions in tprK donor sites currently circulate and are associated with diminished TprK antigenic diversity.

Clinical presentation of early syphilis and genomic sequences of Treponema pallidum strains in patient specimens and isolates obtained by rabbit inoculation.

BACKGROUND: The global resurgence of syphilis necessitates vaccine development. METHODS: We collected ulcer exudates and blood from 17 primary syphilis (PS) participants and skin biopsies and blood from 51 secondary syphilis (SS) participants in Guangzhou, China for Treponema pallidum subsp. pallidum (TPA) qPCR, whole genome sequencing (WGS), and isolation of TPA in rabbits. RESULTS: TPA DNA was detected in 15 of 17 ulcer exudates and 3 of 17 blood PS specimens. TPA DNA was detected in 50 of 51 SS skin biopsies and 27 of 51 blood specimens. TPA was isolated from 47 rabbits with success rates of 71% (12/17) and 69% (35/51), respectively, from ulcer exudates and SS bloods. We obtained paired genomic sequences from 24 clinical samples and corresponding rabbit isolates. Six SS14- and two Nichols-clade genome pairs contained rare discordances. Forty-one of the 51 unique TPA genomes clustered within SS14 subgroups largely from East Asia, while 10 fell into Nichols C and E subgroups. CONCLUSIONS: Our TPA detection rate was high from PS ulcer exudates and SS skin biopsies and over 50% from SS blood, with TPA isolation in over two-thirds of samples. Our results support the use of WGS from rabbit isolates to inform vaccine development.

The incidence of new cases of syphilis has skyrocketed globally in the twenty-first century. This global resurgence requires new strategies, including vaccine development. As part of an NIH funded Cooperative Research Center to develop a syphilis vaccine, we established a clinical research site in Guangzhou, China to better define the local syphilis epidemic and obtain samples from patients with primary and secondary syphilis for whole genome sequencing (WGS) of circulating Treponema pallidum strains. Inoculation of rabbits enabled us to obtain T. pallidum genomic sequences from spirochetes disseminating in blood, a compartment of immense importance for syphilis pathogenesis. Collectively, our results further clarify the molecular epidemiology of syphilis in southern China, enrich our understanding of the manifestations of early syphilis, and demonstrate that the genomic sequences of spirochetes obtained by rabbit inoculation accurately represent those of the spirochetes infecting the corresponding patients.

Long-term in vitro exposure of Treponema pallidum to sub-bactericidal doxycycline did not induce resistance: Implications for doxy-PEP and syphilis.

Doxycycline post-exposure prophylaxis (doxy-PEP) could significantly reduce syphilis incidence. However, the increase in intermittent doxycycline usage might select resistant Treponema pallidum (T. pallidum) strains. To assess whether resistance to doxycycline could be induced in this pathogen, we exposed the SS14 strain in vitro both intermittently and continuously to a sub-bactericidal doxycycline concentration that still exerts antibiotic pressure. During and after each exposure experiment, we assessed the doxycycline minimal inhibitory concentration in test and control treponemes and performed whole genome sequencing, concluding that no resistance developed. This work suggests that doxycycline-resistant T. pallidum is not an immediate threat for doxy-PEP implementation.

Prevalence and Predictors of Oral Treponema pallidum Detection by Quantitative Polymerase Chain Reaction in Early Syphilis.

BACKGROUND: Treponema pallidum prevalence and burden at oral and lesion sites in adults with early syphilis were assessed by quantitative polymerase chain reaction (qPCR). Factors associated with oral shedding were also examined. METHODS: Pretreatment oral and lesion swabs were collected from adults with early syphilis in a US multicenter syphilis treatment trial. Oral swabs were collected in the presence and absence of oral lesions. Following DNA extraction, qPCR and whole-genome sequencing (WGS) were performed to assess burden and strain variability. RESULTS: All 32 participants were male, mean age was 35 years, and 90.6% with human immunodeficiency virus (HIV). T. pallidum oral PCR positivity varied by stage: 16.7% primary, 44.4% secondary, and 62.5% in early latent syphilis. Median oral T. pallidum burden was highest in secondary syphilis at 63.2 copies/µL. Lesion PCR positivity was similar in primary (40.0%) and secondary syphilis (38.5%). Age 18-29 years was significantly associated with oral shedding (vs age 40+ years) in adjusted models. WGS identified 2 distinct strains. CONCLUSIONS: T. pallidum DNA was directly detected at oral and lesion sites in a significant proportion of men with early syphilis. Younger age was associated with oral shedding. Ease of oral specimen collection and increased PCR availability suggest opportunities to improve syphilis diagnostic testing. Clinical Trials Registration. NCT03637660.

In-Depth Proteome Coverage of In Vitro-Cultured Treponema pallidum and Quantitative Comparison Analyses with In Vivo-Grown Treponemes.

Previous mass spectrometry (MS)-based global proteomics studies have detected a combined total of 86% of all Treponema pallidum proteins under infection conditions (in vivo-grown T. pallidum). Recently, a method was developed for the long-term culture of T. pallidum under in vitro conditions (in vitro-cultured T. pallidum). Herein, we used our previously reported optimized MS-based proteomics approach to characterize the T. pallidum global protein expression profile under in vitro culture conditions. These analyses provided a proteome coverage of 94%, which extends the combined T. pallidum proteome coverage from the previously reported 86% to a new combined total of 95%. This study provides a more complete understanding of the protein repertoire of T. pallidum. Further, comparison of the in vitro-expressed proteome with the previously determined in vivo-expressed proteome identifies only a few proteomic changes between the two growth conditions, reinforcing the suitability of in vitro-cultured T. pallidum as an alternative to rabbit-based treponemal growth. The MS proteomics data have been deposited in the MassIVE repository with the data set identifier MSV000093603 (ProteomeXchange identifier PXD047625).

Risk for Donor-Derived Syphilis after Kidney Transplantation, China, 2007-2022.

To evaluate the risk of acquiring syphilis from a donated kidney, we evaluated kidney transplantation pairs from West China Hospital, Sichuan, China, during 2007-2022. Donor-derived syphilis was rare. Risk may be higher if donors have active syphilis and may be reduced if recipients receive ceftriaxone.

Treponema pallidum lipoprotein Tp0768 promotes the migration and adhesion of THP-1 cells to vascular endothelial cells through stress of the endoplasmic reticulum and the NF-κB/HIF-1α pathway.

Endothelial cell injury is a key factor in the spread of infection and pathogenicity of Treponema pallidum. The migration and adhesion reaction mediated by T. pallidum lipoprotein plays an important role. This study aimed to systematically explore the migration and adhesion effect of T. pallidum lipoprotein Tp0768 and its molecular mechanism. Stimulating vascular endothelial cells with Tp0768 increased the expression of ICAM-1, MCP-1, and IL-8. Moreover, it promoted the migration and adhesion of THP-1 cells to vascular endothelial cells. Our results revealed that Tp0768 promoted the THP-1 cells migrating and adhering to vascular endothelial cells by the PERK and IRE-1α pathways of endoplasmic reticulum (ER) stress. We further demonstrated that the inhibition of the NF-κB pathway and the downregulation of hypoxia-inducible factor 1 alpha (HIF-1α) reduced the mRNA levels of ICAM-1, MCP-1, and IL-8 induced by Tp0768. Also, the adhesion rate of THP-1 cells to endothelial cells decreased. After inhibiting ER stress, NF-κB p65 nuclear translocation was weakened, and the mRNA level of HIF-1α was also significantly downregulated. Our results indicated that T. pallidum lipoprotein Tp0768 promoted the migration and adhesion of THP-1 cells to vascular endothelial cells through ER stress and NF-κB/HIF-1α pathway.

Uncovering the mechanisms of host mitochondrial cardiolipin release in syphilis: Insights from human microvascular endothelial cells.

The release of host mitochondrial cardiolipin is believed to be the main factor that contributes to the production of anti-cardiolipin antibodies in syphilis. However, the precise mechanism by which mitochondria release cardiolipin in this context remains elusive. This study aimed to elucidate the mechanisms underlying mitochondrial cardiolipin release in syphilis. We conducted a cardiolipin quantitative assay and immunofluorescence analysis to detect mitochondrial cardiolipin release in human microvascular endothelial cells (HMEC-1), with and without Treponema pallidum (Tp) infection. Furthermore, we explored apoptosis, a key mechanism for mitochondrial cardiolipin release. The potential mediator molecules were then analyzed through RNA-sequence and subsequently validated using in vitro knockout techniques mediated by CRISPR-Cas9 and pathway-specific inhibitors. Our findings confirm that live-Tp is capable of initiating the release of mitochondrial cardiolipin, whereas inactivated-Tp does not exhibit this capability. Additionally, apoptosis detection further supports the notion that the release of mitochondrial cardiolipin occurs independently of apoptosis. The RNA-sequencing results indicated that microtubule-associated protein2 (MAP2), an axonogenesis and dendrite development gene, was up-regulated in HMEC-1 treated with Tp, which was further confirmed in syphilitic lesions by immunofluorescence. Notably, genetic knockout of MAP2 inhibited Tp-induced mitochondrial cardiolipin release in HMEC-1. Mechanically, Tp-infection regulated MAP2 expression via the MEK-ERK-HES1 pathway, and MEK/ERK phosphorylation inhibitors effectively block Tp-induced mitochondrial cardiolipin release. This study demonstrated that the infection of live-Tp enhanced the expression of MAP2 via the MEK-ERK-HES1 pathway, thereby contributing to our understanding of the role of anti-cardiolipin antibodies in the diagnosis of syphilis.

Does cold storage of blood before transfusion prevent the transmission of syphilis? A systematic review and meta-analysis.

BACKGROUND AND OBJECTIVES: Although screening of donated blood for syphilis is almost universally applied, its cost-effectiveness is questioned because of the low prevalence of transfusion-transmitted syphilis and a widespread belief that the syphilis-causing bacterium Treponema pallidum is very vulnerable to cold storage. Since the latter claim is not yet supported by a systematic review, we investigated whether syphilis can be transmitted via transfusion following prolonged (cold or room temperature) storage of blood products. MATERIALS AND METHODS: MEDLINE, PMC and NCBI bookshelf (PubMed interface), Cochrane Library, Embase, Web of Science and CINAHL were searched up to 17 January 2023. RESULTS: Nine experimental animal studies and one observational human study were included. Meta-analysis showed that storing artificially infected human (six studies; risk ratio [RR] = 0.37, 95% confidence interval [CI]: 0.22-0.64, p = 0.0003) or rabbit (two studies; RR = 0.08, 95% CI: 0.01 to 0.55, p = 0.01) blood for more than 72 h before intratesticular injection significantly decreased the number of recipient animals that develop syphilis. Nonetheless, the possibility of syphilis transmission remained for up to 7 days. Differences could not be found for rabbit plasma (p = 0.60) or naturally infected rabbit blood (p = 0.28). There was limited evidence from one study in favour of the storage of artificially infected human platelets for over 72 h at cold temperatures (RR = 0.13, 95% CI: 0.03-0.52, p = 0.004) but not at room temperature (p = 0.12). CONCLUSION: Even though the infectivity of T. pallidum-spiked blood may decrease after 72 h of cold storage, the possibility for transfusion-transmitted syphilis may remain for several days after. The evidence is very uncertain, and conclusions are hindered by a lack of sufficiently powered studies and studies in humans. In addition, T. pallidum concentrations used in animal studies may be unrealistically high.

A novel syphilis Treponema pallidum lipoprotein peptide antigen diagnostic assay using red cell kodecytes in routine blood centre column agglutination testing platforms.

BACKGROUND AND OBJECTIVES: The detection of treponemal antibodies, which are used to make a diagnosis of syphilis, is important both for diagnostic purposes and as a mandatory blood donor test in most countries. We evaluated the feasibility of using Kode Technology to make syphilis peptide red cell kodecytes for use in column agglutination serologic platforms. MATERIALS AND METHODS: Candidate Kode Technology function-spacer-lipid (FSL) constructs were made for the Treponema pallidum lipoprotein (TmpA) of T. pallidum, using the peptide and FSL selection algorithms, and then used to make kodecytes. Developmental kodecytes were evaluated against a large range of syphilis antibody reactive and non-reactive samples in column agglutination platforms and compared against established methodologies. Overall, 150 reactive and 2072 non-reactive Syphicheck assay (a modified T. pallidum particle agglutination) blood donor samples were used to evaluate the agreement rate of the developed kodecyte assay. RESULTS: From three FSL-peptide candidate constructs, one was found to be the most suitable for diagnostics. Of 150 Syphicheck assay reactive samples, 146 were TmpA-kodecyte reactive (97.3% agreement), compared with 58.0% with the rapid plasmin reagin (RPR) assay for the same samples. Against the 2072 expected syphilis non-reactive samples the agreement rate for TmpA-kodecytes was 98.8%. CONCLUSION: TmpA-kodecytes are viable for use as cost-effective serologic reagent red cells for the detection of treponemal antibodies to diagnose syphilis with a high level of specificity in blood centres. This kodecyte methodology also potentially allows for introduction of the reverse-algorithm testing into low-volume laboratories, by utilizing existing transfusion laboratory infrastructure.

Syphilis susceptibility factors atlas: A wide-angled Mendelian randomization study.

OBJECTIVE: The pathogenic mechanisms of syphilis and the host defense mechanisms against syphilis remain poorly understood. Exploration of the susceptibility factors of syphilis may provide crucial clues for unraveling its underlying mechanisms. METHODS: A two-sample Mendelian Randomization framework was utilized, and the inverse-variance weighted method was used as the main analysis. All data was sourced from Genome-wide association studies datasets from 2015 to 2022 in Europe, and all participants were of European descent. Only summary-level statistics were used. Sensitivity analyses were conducted to evaluate the heterogeneity and pleiotropy of the datasets. RESULTS: Our study established 18 exposure factors (12 risk factors and 6 protective factors) for syphilis susceptibility. Twelve factors encompassing body mass index, waist circumference, darker natural skin, cooked vegetable intake, processed meat intake, diabetes mellitus, glucose regulation disorders, gout, autoimmune diseases, rheumatoid arthritis, diverticulitis, and longer menstrual cycles were found to increase susceptibility to syphilis. In contrast, 6 factors including easier skin tanning, blonde natural hair color, irritability, higher neuroticism scores, extended sleep duration, and delayed age at first sexual intercourse were connected to a reduced risk of syphilis infection (all P < 0.05). CONCLUSIONS: This study identified 18 influencing factors of syphilis susceptibility. These findings offered novel insights for further probing into the underlying pathogenic mechanisms of syphilis and underscored the importance of multifaceted prevention strategies against syphilis.

Novel and characteristic radiological features of neurosyphilis: a case series.

BACKGROUND: Treponema pallidum can invade the central nervous system (CNS) early in its infection, causing neurosyphilis. Neurosyphilis typically presents with meningovasculitis in the acute or subacute phase, while tabes dorsalis and dementia paralytica are classical conditions in the later stages. However, syphilis is often misdiagnosed as other conditions such as tumors or autoimmune diseases including vasculitis and encephalitis, which is why the condition is known as "The Great Mimicker." The increasing incidence of syphilis in recent years emphasizes the importance of early diagnosis and treatment; however, its multiple clinical manifestations impose diagnostic challenges for clinicians because it resembles other diseases. In this case series, we present the impressive manifestations of neurosyphilis through three unique radiological presentations. CASE PRESENTATION: Case 1 details optic nerve involvement in an HIV-positive male, where MRI and fundoscopic findings confirmed syphilitic optic neuritis. Case 2 describes a patient in her pregnancy initially suspected of acoustic neuroma on MRI, later diagnosed with syphilitic gumma affecting the inner ear canal. Case 3 is a young male with clinical features mimicking temporal arteritis, ultimately identified as skull osteomyelitis secondarily causing inflammation of the musculus temporalis and meningitis. CONCLUSIONS: These cases underscore the necessity of considering syphilis in differential diagnoses, given the diversity of its clinical presentations. Radiology plays an important role in avoiding unnecessary interventions. The increasing prevalence of recurrent syphilis imposes diagnostic challenges, emphasizing the importance of the early diagnosis and treatment of neurosyphilis by clinicians.

A multi-country comparative study of two treponemal tests for the serodiagnosis of syphilis amongst men who have sex with men (MSM): Chemo-luminescent assay vs Treponema pallidum particle agglutination assay.

INTRODUCTION: International guidelines recommend routine screening for syphilis (aetiological agent: Treponema pallidum subspecies pallidum) amongst key populations and vulnerable populations using tests detecting treponemal and non-treponemal antibodies. Whilst treponemal tests have high sensitivities and specificities, they differ regarding subjective or objective interpretation, throughput and workload. Chemiluminescence immunoassays (CLIAs) are cost- and time-effective automated methods for detecting treponemal antibodies. The Treponema pallidum particle agglutination assay (TPPA) has been considered the "gold standard" treponemal assay, however, this includes a highly manual procedure, low throughput and subjective interpretation. The present multi-country study evaluated the ADVIA Centaur® Syphilis CLIA (Siemens Healthcare) assay compared to the reference SERODIA-TP·PA® (Fujirebio Diagnostics) for the serodiagnosis of syphilis amongst men who have sex with men (MSM). METHOD: 1,485 MSM were enrolled in Brighton (UK), Malta, and Verona (Italy) as part of a larger WHO multi-country and multi-site ProSPeRo study. Ethical approval was obtained. Serum was tested with the ADVIA Centaur® Syphilis CLIA assay and SERODIA-TP·PA®, in accordance with the manufacturers' instructions, for a first round of validation. A second round of validation was carried out for discrepant results that were additionally tested with both Western Blot (Westernblot EUROIMMUN®) and an Immunoblot (INNO-LIA, Fujirebio Diagnostics). Sensitivity, specificity, positive and negative predictive value (PPV and NPV), likelihood ratios (positive/negative), and the Diagnostic Odds Ratio (DOR)/pre-post-test probability (Fagan's nomogram) were calculated. RESULTS: Out of 1,485 eligible samples analysed in the first phase, the SERODIA-TP·PA® identified 360 positive and 1,125 negative cases. The ADVIA Centaur® Syphilis CLIA assay (Siemens) identified 366 positives, missclassifying one TPPA-positive sample. In the second phase, the ADVIA Centaur® Syphilis CLIA resulted in 1 false negative and 4 false positive results. Considering the syphilis study prevalence of 24% (95% CI: 22-26.7), The sensitivity of the ADVIA Centaur® Syphilis CLIA assay was 99.7% (95% CI: 98.5-100), and the specificity was 99.4% (95% CI: 98.7-99.7). The ROC area values were 0.996 (95% CI: 0.992-0.999), and both the PPV and NPV values were above 98% (PPV 98.1%, 95% CI: 96.1-99.2; NPV 99.9%, 95% CI: 99.5-100). CONCLUSIONS: The ADVIA Centaur® Syphilis CLIA assay showed similar performance compared to the SERODIA-TP·PA®. Considering the study is based on QUADAS principles and with a homogeneous population, results are also likely to be generalisable to MSM population but potentially not applicable to lower prevalence populations routinely screened for syphilis. The automated CLIA treponemal assay confirmed to be accurate and appropriate for routine initial syphilis screening, i.e. when the reverse testing algorithm is applied.

Tracking Chlamydia and Syphilis in the Detroit Metro Area by Molecular Analysis of Environmental Samples.

This paper describes one of the first studies applying wastewater surveillance to monitor Chlamydia and Syphilis and back-estimate infections in the community, based on bacterial shedding and wastewater surveillance data. Molecular biology laboratory methods were optimized, and a workflow was designed to implement wastewater surveillance tracking Chlamydia and Syphilis in the Detroit metro area (DMA), one of the most populous metropolitan areas in the U.S. Untreated composite wastewater samples were collected weekly from the three main interceptors that service DMA, which collect wastewater and discharge it to the Great Lakes Water Authority Water Resource Recovery Facility. Additionally, untreated wastewater was also collected from street manholes in three neighborhood sewersheds in Wayne, Macomb, and Oakland counties. Centrifugation, DNA extraction, and ddPCR methods were optimized and performed, targeting Chlamydia trachomatis and Treponema pallidum, the causative agents of Chlamydia and Syphilis, respectively. The limit of blank and limit of detection methods were determined experimentally for both targets. Both targets were detected and monitored in wastewater between December 25th, 2023, and April 22nd, 2024. The magnitudes of C. trachomatis and T. pallidum concentrations observed in neighborhood sewersheds were higher as compared to the concentrations observed in the interceptors. Infections of Chlamydia and Syphilis were back-estimated through an optimized formula based on shedding dynamics and wastewater surveillance data, which indicated potentially underreported conditions relative to publicly available clinical data.

Seroconversion and seroprevalence of TORCH infections in a pregnant women cohort study, Mombasa, Kenya, 2017-2019.

Women infected during pregnancy with TORCH (Toxoplasmosis, Other, Rubella, Cytomegalovirus, and Herpes simplex viruses) pathogens have a higher risk of adverse birth outcomes including stillbirth / miscarriage because of mother-to-child transmission. To investigate these risks in pregnant women in Kenya, we analyzed serum specimens from a pregnancy cohort study at three healthcare facilities. A sample of 481 participants was selected for TORCH pathogen antibody testing to determine seroprevalence. A random selection of 285 from the 481 participants was selected to measure seroconversion. These sera were tested using an IgG enzyme-linked immunosorbent assay against 10 TORCH pathogens. We found that the seroprevalence of all but three of the 10 TORCH pathogens at enrollment was >30%, except for Bordetella pertussis (3.8%), Treponema pallidum (11.4%), and varicella zoster virus (0.5%). Conversely, very few participants seroconverted during their pregnancy and were herpes simplex virus type 2 (n = 24, 11.2%), parvovirus B19 (n = 14, 6.2%), and rubella (n = 12, 5.1%). For birth outcomes, 88% of the participant had live births and 12% had stillbirths or miscarriage. Cytomegalovirus positivity at enrolment had a statistically significant positive association with a live birth outcome (p = 0.0394). Of the 10 TORCH pathogens tested, none had an association with adverse pregnancy outcome.

Immunohistochemistry and RT-PCR as ancillary tools in the diagnosis of acquired oral syphilis.

OBJECTIVE: To investigate Treponema pallidum detection using immunohistochemistry (IHC) and reverse transcription-polymerase chain reaction (RT-PCR) assays in acquired oral syphilis (AOS). MATERIALS AND METHODS: Thirty-seven paraffin-embedded tissue specimens of AOS (32 secondary and five primary) were analyzed, integrating double-positive serological results with clinicodemographic and histopathological data. T. pallidum presence was semiquantitatively assessed by IHC, while RT-PCR targeted T. pallidum DNA. Sensitivity, specificity, and the area under the curve (AUC) were calculated with 95% confidence intervals (CI). RESULTS: The study included mostly females (62.2%) with a mean age of 27.1 years. T. pallidum was detected in all samples by IHC, predominantly in the epithelium across all layers (43.2%). RT-PCR identified T. pallidum DNA in 32 cases, with negative results observed in cases of secondary AOS. The AUC for IHC versus disease stage was 62.5% (95% CI: 45.1-77.8), and for RT-PCR, it was 57.8% (95% CI: 40.5-73.8). The AUC comparing IHC to RT-PCR was 83.8% (95% CI: 67.9-93.8). CONCLUSION: This study represents the first attempt to evaluate the proposed direct detection algorithm for AOS. IHC and RT-PCR serve as ancillary tools for detecting T. pallidum in both primary and secondary stages of AOS.

Epstein-Barr virus-positive monoclonal lymphoplasmacytic proliferation associated with neurosyphilis in an immunocompetent patient: A case report.

Syphilis is an infectious disease caused by the spirochete bacterium Treponema pallidum. Neurosyphilis results from the infection of the nervous system with Treponema pallidum, which can occur at any stage of syphilis. Neurosyphilis is often overlooked because of its rarity. Early-stage neurosyphilis with brain mass formation is rare. We present a case of early-stage neurosyphilis with prominent Epstein-Barr virus (EBV)-positive monoclonal lymphoplasmacytic proliferation in an immunocompetent patient. A 36-year-old man presented with a chief complaint of a progressively worsening headache, a newly developed skin rash, and a fever. Magnetic resonance imaging showed a mass lesion, which measured 18 mm in diameter, in the left frontal lobe of the cerebrum. The patient underwent an emergency operation to remove the abscess. A pathological investigation revealed complex findings. There was an abscess in the cerebrum. Lymphoplasmacytic meningitis was also noted. In addition, a vaguely nodular lesion, which was composed of plasmacytoid and lymphoid cells, was observed around the abscess. Immunohistochemically, an anti-Treponema pallidum antibody revealed numerous Treponemas around the abscess. In situ hybridization revealed that the plasmacytoid and lymphoid cells were Epstein-Barr encoding region (EBER)-positive; κ-positive cells were significantly more prevalent than λ-positive cells, suggesting light-chain restriction. Postoperatively, parenteral antibiotics were administered for four weeks. The patient has been free of recurrence for two years since the surgery. No association between neurosyphilis and EBV-positive lymphoplasmacytic proliferation has ever been reported. Mass formation in early-stage neurosyphilis is an exceptionally rare event. The present case indicates that in syphilis patients, lymphoproliferative disorders that lead to mass formation may be caused by concomitant EBV reactivation. Furthermore, when treating patients with mass lesions of the central nervous system, it is important to check their medical history and perform laboratory screening for infectious diseases to avoid overlooking syphilis infections.

A case of early-onset congenital syphilitic osteomyelitis of the calcaneus and literature review.

BACKGROUND: Congenital syphilis (CS) is a sexually transmitted disease caused by Treponema pallidum (TP). When the skeletal system is involved, it often results in multiple, symmetrical bone destruction at the epiphyses of long tubular bones such as the humerus and radius, rarely involving the calcaneus. This article reports a case of calcaneal osteomyelitis caused by TP in a child with no other bone damage and subtle clinical manifestations, No similar cases have been reported. CASE PRESENTATION: A 4-month-old male infant presented with right foot swelling without any obvious cause and no history of trauma. X-ray and CT scans showed bone loss in the calcaneus and surrounding soft tissue swelling. Review of past medical records revealed that the infant had been diagnosed with CS infection during a hospital stay for "pneumonia" at one month old. The parents refused surgery, opting for conservative treatment at an external hospital for three weeks, during which the symptoms of the affected foot showed no significant improvement. Subsequently, the child was treated at our hospital with surgery, including lesion removal and cast fixation, followed by oral antibiotic treatment. The last follow-up showed no swelling or tenderness in the affected foot, with good mobility, and X-rays indicated that the bone had essentially returned to normal. CONCLUSIONS: Early CS rarely involves the calcaneus. When diagnosing unexplained calcaneal osteomyelitis in infants, this rare cause should be considered. A thorough medical history should be taken and a careful physical examination conducted. Once diagnosed, timely surgical debridement and appropriate antibiotic therapy targeting TP infection are required. Early identification and intervention can result in a good prognosis without related complications.

Diagnostic and Therapeutic Approaches for a Diabetic Patient Presenting with Secondary Syphilis and Severe Odynophagia.

Syphilis, an infectious disease caused by the spirochete Treponema pallidum, represents a pervasive global epidemic. Secondary syphilis is typically marked by the emergence of highly contagious mucocutaneous manifestations, including non-pruritic rashes on the palms and soles of the feet, alopecia, mucous patches, and condyloma lata. Here, we report a rare case of a 30-year-old male with newly discovered type 2 diabetes mellitus who presented with severe odynophagia due to secondary syphilis, confirmed by both nontreponemal VDRL/RPR and treponemal TPHA tests. Following the administration of a single-dose intramuscular injection of benzathine penicillin G 2.4 million units, the symptoms gradually decreased, allowing the patient to regain his health.