Laboratory diagnosis and interpretation of tests for syphilis

An Automated Syphilis Serology Record Search and Review Algorithm to Prioritize Investigations by Health Departments

BACKGROUND

Reactive syphilis serologies are investigated by health departments to determine if they represent new infection, reinfection, or treatment failure. Serologies prioritized for investigation based on nontreponemal test titer and age (using a "reactor grid") undergo manual record search and review. We developed a computerized algorithm that automates the record search and review.

METHODS

We developed and tested the algorithm using a Florida Department of Health data set containing serologies reported January 2016 to December 2018 and previous records linked to each individual. The algorithm was based on the syphilis case definition, which requires (except primary cases with signs and symptoms) (1) a positive treponemal test result and a newly positive nontreponemal test result or (2) a 4-fold increase in nontreponemal test titer. Two additional steps were added to avoid missing cases. New York City Department of Health and Mental Hygiene validated this algorithm.

RESULTS

The algorithm closed more investigations (49.9%) than the reactor grid (27.0%). The algorithm opened 99.4% of the individuals investigated and labeled as cases by the health department; it missed 75 cases. Many investigations opened by the algorithm were closed by the reactor grid; we could not assess how many would have been cases. In New York City, the algorithm closed 70.9% of investigations, likely because more individuals had previous test in the database (88.2%) compared with Florida (56.5%).

CONCLUSIONS

The automated algorithm successfully searched and reviewed records to help identify cases of syphilis. We estimate the algorithm would have saved Florida 590 workdays for 3 years.

A New Specimen for Syphilis Diagnosis: Evidence by High Loads of Treponema pallidum DNA in Saliva

BACKGROUND

DNA from many pathogens can be detected in saliva. However, the presence and quantity of Treponema pallidum DNA in patients with syphilis in saliva is unknown.

METHODS

234 patients with syphilis with different stages and 30 volunteers were enrolled. Paired saliva and plasma samples were collected from all participants. Consecutive saliva samples from 9 patients were collected every 4 hours following treatment. Treponema pallidum DNA in samples was determined by nested polymerase chain reaction (PCR) and droplet digital PCR targeting polA and Tpp47.

RESULTS

Treponema pallidum DNA detection rates in saliva and plasma were 31.0% (9/29) and 51.7% (15/29) in primary syphilis (P = .11), 87.5% (63/72) and 61.1% (44/72) in secondary syphilis (P < .001), 25.6% (21/82) and 8.5% (7/82) in latent syphilis (P = .004), and 21.6% (11/51) and 5.9% (3/51) in symptomatic neurosyphilis (P = .021), respectively. Median (range) loads of Tpp47 and polA in saliva were 627 (0-101 200) and 726 (0-117 260) copies/mL, respectively, for patients with syphilis. In plasma, however, loads of Tpp47 and polA were low: medians (range) of 0 (0-149.6) and 0 (0-176) copies/mL, respectively. Loads of T. pallidum DNA in saliva during treatment fluctuated downward; the clearance time was positively correlated with the loads of T. pallidum DNA before treatment.

CONCLUSIONS

Collection of saliva is noninvasive and convenient. The high loads of T. pallidum DNA in saliva and reduction after treatment indicated that saliva can be not only a diagnostic fluid for syphilis but also an indicator of therapeutic effectiveness.

Evaluation of the effect of extended refrigerated storage of serum and plasma specimens on syphilis serologic test results

The effect of extended refrigerated storage of 14 serum and plasma specimens on 5 syphilis serologic tests was evaluated for 16 weeks. Higher stability of nontreponemal and treponemal antibodies in serum was recorded compared to plasma. Described work may provide insights on refrigerated specimens' stability and suitability for syphilis tests.

Sudden death due to rupture of an aortic syphilitic aneurysm

A 26-year-old man who suddenly collapsed and died was found at autopsy to have a ruptured aortic aneurysm which had the classic "tree bark" appearance of tertiary syphilis. Tracking of blood into the pericardial sac had resulted in sudden death from cardiac tamponade. Serological results were consistent with syphilis and HIV was excluded. Sudden death in a young HIV-negative man from the effects of syphilis is exceedingly rare nowadays.

Evaluation of The Diagnostic Algorithms for Serodiagnosis of Syphilis

We analyzed the performance parameters of the traditional and the reverse algorithms to find out which one is more convenient for serodiagnosis of syphilis. In total, 4789 serum samples were obtained in a cross-sectional study. Venereal Disease Research Laboratory (VDRL), Treponema pallidum Haemagglutination Assay (TPHA) and Chemiluminescent Microparticle Immunoassay (CMIA) tests were performed for every serum sample. In case of discordance between results, the TPHA was applied as a second treponemal test. Overall, 207 patients were serodiagnosed with syphilis. Among 4789 subjects tested, 125 (2.6%) and 206 (4.3%) were positive using the traditional algorithm and the reverse algorithm, respectively. The missed diagnosis rate of the traditional algorithm was 42.5%. The reverse algorithm had higher sensitivity than the traditional algorithm. Sensitivity levels of the traditional and the reverse algorithms were 57.49% and 99.85% respectively. The false positivity of the reverse algorithms was 0.02%.

Unusual erythematous plaque with white scales, a case of acquired syphilis in a child and literature review

BACKGROUND

Syphilis in children is uncommon with the mode of infection for this rare condition likely being congenital or acquired. While most acquired cases of syphilis in children result from sexual abuse, children can also be infected with syphilis through kissing, breastfeeding, sharing of daily necessities or pre-chewed food. Here, we report a case of acquired secondary syphilis in a child due to consumption of pre-chewed-food and provide a review of the literature on the characteristics of acquired syphilis in preschool children.

CASE PRESENTATION

A 3-year-old girl presented with erythematous plaques and scales on her head, neck, and thighs as well as flat red papules with a moist, well circumscribed surface covered with a grayish-white film. The grandmother who cared for the girl was in the habit of pre-chewing food before giving it to the girl. The child and grandmother tested positive for RPR. The girl, who was not sexually abused, was diagnosed with acquired secondary syphilis, resulting from the transmission of pre-chewed food from her grandmother.

CONCLUSIONS

Our case report and literature review reveal that close contact among family members can result in the transmission of syphilis. We recommend that pre-chewing food should be discouraged by caregivers when caring for their children to avoid disease transmission.

Brazilian Protocol for Sexually Transmitted Infections 2020: syphilis diagnostic tests

The recommendations for diagnostic tests for investigating syphilis are part of the Clinical Protocol and Therapeutic Guidelines for Comprehensive Care for People with Sexually Transmitted Infections and the Technical Manual for Syphilis Diagnosis, published by the Brazilian Ministry of Health. These recommendations were developed based on scientific evidence and discussions with a panel of experts. This article presents direct tests to detect Treponema pallidum in lesions and algorithms that combine treponemal and non-treponemal antibody tests to assist in syphilis diagnosis, with the aim of contributing to the efforts of health service managers and health professionals in qualifying health care. The article also covers the use of non-treponemal tests to investigate neurosyphilis and guidelines for interpreting non-treponemal antibody titers in monitoring the treatment and diagnosis of congenital syphilis, as well as prospects for innovations in diagnosis. The critical role of rapid immunochromatographic treponemal tests for public health and for addressing syphilis is also highlighted.

Highlighted excerpt: During the natural evolution of syphilis, activity periods with distinct clinical, immunological, and histopathological characteristics are interspersed with latent periods when there are no signs or symptoms, making access to tests critical for early diagnosis.

Immunological tests and their interpretation in uveitis

Uveitis is a complex disorder including both infectious and non-infectious etiologies. Clinical diagnosis is a challenge because many diseases share common clinical signs. Laboratory support is crucial for confirming the clinical diagnosis. Laboratory diagnosis includes direct tests and indirect tests. For example smear, culture, and molecular diagnostics demonstrate the pathogens, hence they are direct tests. Immunologic tests employ an antigen to detect presence of antibodies to a pathogen, or an antibody to detect the presence of an antigen, of the pathogen in the specimens. The immunological tests used in laboratories are made by producing artificial antibodies that exactly “match” the pathogen in question. When these antibodies come into contact with a sample they bind to the matching pathogen if found in the sample. Hence they are grouped under indirect evidence. There are several investigations in uveitis to reach the confirmed diagnosis including microbiological, immunological, imaging and molecular diagnostic testing. In this section we will discuss immunological investigations of infectious and non-infectious uveitis.

The laboratory diagnosis of Syphilis

Syphilis is a multisystem infection caused by the spirochaete Treponema pallidum Currently, cases of possible syphilis are commonly investigated using the treponemal serological tests T. pallidum IgG chemiluminescence immunoassay (CLIA) and the T. pallidum particle agglutination (TPPA). The non-treponemal rapid plasma reagin (RPR) flocculation test is used to assess disease activity. There has been a resurgence of syphilis diagnoses in Australia. Large foci of infection have been identified in isolated communities. The remoteness of these locations, in conjunction with the particular socio-cultural characteristics of the population, pose unique challenges to the traditional diagnostic and treatment paradigms for syphilis. As a consequence of this increased incidence of syphilis, there has been interest in the utility of point of care tests (POCT), nucleic acid amplification tests (NAAT), the role of IgM testing in suspected congenital syphilis, and the laboratory investigation of possible neurosyphilis. This review looks at the current status of traditional serological assays and provides an update on more recent methods. It assesses the published literature in this area and makes recommendations for the rational use of pathology testing to aid in the diagnosis of the many facets of syphilis.

Molecular and Direct Detection Tests for Treponema pallidum Subspecies pallidum: A Review of the Literature, 1964-2017

Direct detection methods for Treponema pallidum include dark-field microscopy (DFM), direct fluorescence antibody (DFA) testing, immunohistochemistry (IHC), and nucleic acid amplification tests (NAATs). Here, we reviewed the relevant syphilis diagnostic literature to address 2 main questions with respect to T. pallidum direct detection techniques: “What are the performance characteristics for each direct detection test for T. pallidum and what are the optimal specimen types for each test?” and “What options are available for T. pallidum molecular epidemiology?” To answer these questions, we searched 5 electronic databases (OVID Medline, OVID Embase, CINAHL, Cochrane Library, and Scopus) from 1964 to 2017 using relevant search terms and identified 1928 articles, of which 37 met our inclusion criteria. DFM and DFA sensitivities ranged from 73% to 100% in cases of primary syphilis; and while sensitivity using silver stain histopathology for T. pallidum was generally low (0%–41%), higher performance characteristics were observed for T. pallidum–specific IHC (49–92%). Different genes have been targeted by T. pallidum–specific NAATs, with the majority of studies indicating that sensitivity is primarily dependent on the type of collected biological sample, with highest sensitivity observed in primary lesion exudate (75–95%). Given the rising incidence of syphilis, the development of direct, Food and Drug Administration–cleared T. pallidum NAATs should be considered an immediate priority.

The impact of antenatal syphilis point of care testing on pregnancy outcomes: A systematic review

Background

Mother-to-child transmission of syphilis remains a leading cause of neonatal death and stillbirth, disproportionally affecting women in low-resource settings where syphilis prevalence rates are high and testing rates low. Recently developed syphilis point-of-care tests (POCTs) are promising alternatives to conventional laboratory screening in low-resource settings as they do not require a laboratory setting, intensive technical training and yield results in 10–15 minutes thereby enabling both diagnosis and treatment in a single visit. Aim of this review was to provide clarity on the benefits of different POCTs and assess whether the implementation of syphilis POCTs is associated with decreased numbers of syphilis-related adverse pregnancy outcomes.

Methods

Following the PRISMA guidelines, three electronic databases (PubMed, Medline (Ovid), Cochrane) were systematically searched for intervention studies and cost-effectiveness analyses investigating the association between antenatal syphilis POCT and pregnancy outcomes such as congenital syphilis, low birth weight, prematurity, miscarriage, stillbirth as well as perinatal, fetal or infant death.

Results

Nine out of 278 initially identified articles were included, consisting of two clinical studies and seven modelling studies. Studies compared the effect on pregnancy outcomes of treponemal POCT, non-treponemal POCT and dual POCT to laboratory screening and no screening program. Based on the clinical studies, significantly higher testing and treatment rates, as well as a significant reduction (93%) in adverse pregnancy outcomes was reported for treponemal POCT compared to laboratory screening. Compared to no screening and laboratory screening, modelling studies assumed higher treatment rates for POCT and predicted the most prevented adverse pregnancy outcomes for treponemal POCT, followed by a dual treponemal and non-treponemal POCT strategy.

Conclusion

Implementation of treponemal POCT in low-resource settings increases syphilis testing and treatment rates and prevents the most syphilis-related adverse pregnancy outcomes compared to no screening, laboratory screening, non-treponemal POCT and dual POCT. Regarding the benefits of dual POCT, more research is needed. Overall, this review provides evidence on the contribution of treponemal POCT to healthier pregnancies and contributes greater clarity on the impact of diverse diagnostic methods available for the detection of syphilis.

[Brazilian Protocol for Sexually Transmitted Infections 2020: syphilis diagnostic tests]

The recommendations for diagnostic tests for investigating syphilis are part of the Clinical Protocol and Therapeutic Guidelines for Comprehensive Care for People with Sexually Transmitted Infections and the Technical Manual for Syphilis Diagnosis, published by the Brazilian Ministry of Health. These recommendations were developed based on scientific evidence and discussions with a panel of experts. Aiming to contribute to the efforts of health service managers and health professionals in qualifying health care, this article presents the use of direct tests to detect Treponema pallidum in lesions, as well as algorithms that combine treponemal and non-treponemal antibody tests to assist in the diagnosis of syphilis. The article also covers use of non-treponemal tests to investigate neurosyphilis and guidelines for interpreting non-treponemal antibody titers in monitoring treatment and diagnosis of congenital syphilis, as well as prospects for innovations in diagnosis. The important role of rapid immunochromatographic treponemal tests for public health and for addressing syphilis is also highlighted.

Neurosyphilis Treatment Outcomes After Intravenous Penicillin G Versus Intramuscular Procaine Penicillin Plus Oral Probenecid

BACKGROUND

Data comparing neurosyphilis treatment regimens are limited.

METHODS

Participants were enrolled in a study of cerebrospinal fluid (CSF) abnormalities in syphilis that was conducted at the University of Washington between April 2003 to May 2014. They were diagnosed with syphilis and referred by their providers due to concerns for neurosyphilis. We evaluated 150 people with CSF abnormalities who were treated with either intravenous aqueous penicillin G (PenG) or intramuscular aqueous procaine penicillin G plus oral probenecid (APPG-P). An abnormal CSF diagnosis was defined as a white blood cell (WBC) count >20/µL, a CSF protein reading >50 mg/dL, or a reactive CSF-Venereal Disease Research Laboratory test (VDRL). Hazard ratios for normalization of CSF or serum measures were determined using Cox regression.

RESULTS

In individuals treated with either PenG or APPG-P, CSF WBCs and CSF-VDRL reactivity normalized within 12 months after treatment, while protein normalized more slowly and less completely. There was no relationship between treatment regimen or human immunodeficiency virus (HIV) status and likelihood of normalization of any measure. Among those living with HIV, CSF WBC counts and CSF-VDRL reactivity were more likely to normalize in those treated with antiretrovirals. Unexpectedly, CSF WBCs were more likely to normalize in those with low CD4+ T cell counts. When neurosyphilis was more stringently defined as a reactive CSF-VDRL, the relationship with the CD4+ T cell count remained unchanged.

CONCLUSIONS

In the current antiretroviral treatment era, neurosyphilis treatment outcomes are not different for PenG and APPG-P, regardless of HIV status. The relationship between the normalization of CSF WBC counts and CD4+ T cell counts may indicate continued imprecision in neurosyphilis diagnostic criteria, due to HIV-related CSF pleocytosis.

Syphilitic Aortic Aneurysm: A Rare Entity in the Era of Antibiotics

A thoracic aortic aneurysm is a rare entity of tertiary syphilis in the era of antibiotics. The diagnosis of the aortic aneurysm due to tertiary syphilis may be challenging due to deceptive clinical presentation and rarity of the disease in the western world. We report the case of a 59-year-old man, who presents with worsening shortness of breath and was found to have a large ascending aortic aneurysm on computed tomography angiogram (CTA) of the chest. Further workup demonstrated a positive syphilis test. Untreated earlier stages of syphilis attribute to the development of the ascending aortic aneurysm. The patient was medically treated with IV penicillin and underwent surgical repair of the aortic aneurysm. Histopathology confirmed the diagnosis of syphilitic aortitis. Tertiary syphilis often presents several years after initial infection and usually after a latent phase, making it difficult to diagnose. Syphilitic aortic aneurysms may result in a high mortality rate in untreated patients. Therefore, a high index of suspicion is required for the early recognition of a syphilitic aortic aneurysm. Early treatment with antibiotic therapy and surgical repair of syphilitic aortic aneurysms can prevent life-threatening complications.

The Application of Cytokine Expression Assays to Differentiate Active From Previously Treated Syphilis

To investigate the role of serum cytokine assays to distinguish between active from treated syphilis among serofast patients, we recruited individuals into a prospective cohort study. Participants underwent routine syphilis screening. We selected specimens from a majority cohort of serofast participants with treated and active syphilis. We analyzed specimens with a 62-cytokine multiplex bead-based enzyme-linked immunosorbent assay. Cytokines, brain-derived neurotrophic factor and tumor necrosis factor β, were most predictive. We built a decision tree that was 82.4% accurate, 100% (95% confidence interval, 82%-100%) sensitive, and 45% (18%-75%) specific. Our decision tree differentiated between serum specimens from serofast participants with treated syphilis versus active syphilis.

Laboratory Diagnostic Tools for Syphilis: Current Status and Future Prospects

With the increasing number of patients infected with syphilis in the past 20 years, early diagnosis and early treatment are essential to decline syphilis prevalence. Owing to its diverse manifestations, which may occur in other infections, the disease often makes clinicians confused. Therefore, a sensitive method for detecting T. pallidum is fundamental for the prompt diagnosis of syphilis. Morphological observation, immunohistochemical assay, rabbit infectivity test, serologic tests, and nucleic acid amplification assays have been applied to the diagnosis of syphilis. Morphological observation, including dark-field microscopy, silver-staining, and direct fluorescent antibody staining for T. pallidum, can be used as a direct detection method for chancre specimens in primary syphilis. Immunohistochemistry is a highly sensitive and specific assay, especially in the lesion biopsies from secondary syphilis. Rabbit infectivity test is considered as a sensitive and reliable method for detecting T. pallidum in clinical samples and used as a historical standard for the diagnosis of syphilis. Serologic tests for syphilis are widely adopted using non-treponemal or treponemal tests by either the traditional or reverse algorithm and remain the gold standard in the diagnosis of syphilis patients. In addition, nucleic acid amplification assay is capable of detecting T. pallidum DNA in the samples from patients with syphilis. Notably, PCR is probably a promising method but remains to be further improved. All of the methods mentioned above play important roles in various stages of syphilis. This review aims to provide a summary of the performance characteristics of detection methods for syphilis.

MicroRNA-101-3p, MicroRNA-195-5p, and MicroRNA-223-3p in Peripheral Blood Mononuclear Cells May Serve as Novel Biomarkers for Syphilis Diagnosis

OBJECTIVES

Syphilis is a sexually transmitted disease of global prevalence. Current diagnostic methods lack sensitivity and specificity, which limits the early diagnosis and prognosis of the disease. MiRNAs hold great promise as potential biomarkers for infectious diseases diagnosis. We previously profiled the expression of miRNAs in PBMCs from patients with different stages of syphilis. We aimed to further confirm the miR-101-3p, miR-195-5p, and miR-223-3p expression profiles and evaluate their diagnostic value in syphilis infection.

METHODS

The expression levels of PBMC-derived miR-101-3p, miR-195-5p, and miR-223-3p were analyzed in 133 syphilis patients, 18 non-syphilis patients, and 23 healthy controls by RT-qPCR. ROC analysis was used to evaluate the differentiation power of these miRNAs in syphilis diagnosis, while the correlation between the expression of these miRNAs and TRUST titer was also statistically analyzed.

RESULTS

These miRNAs were significantly upregulated in syphilis patients in a stage-specific manner. ROC analysis indicated that miR-223-3p was powerful in discriminating between controls and patients with early, primary, secondary, and latent syphilis, as well as serological cure; the miR-195-5p/miR-223-3p panel showed an improved capacity to differentiate between syphilis patients, primary, or serofast-stage syphilis and controls, while the three miRNAs combined showed an improved capacity to differentiate latent syphilis or serological cure from controls. Importantly, miR-101-3p and miR-223-3p singly or jointly could specifically distinguish syphilis from non-syphilis patients. Moreover, TRUST titer was significantly correlated with miR-101-3p expression.

CONCLUSIONS

MiR-101-3p, miR-195-5p, and miR-223-3p might singly or jointly be potential diagnostic biomarkers at different stages of syphilis.

Use of a Multiplex PCR Assay To Assess the Presence of Treponema pallidum in Mucocutaneous Ulcerations in Patients with Suspected Syphilis

We evaluated the utility of the commercial Allplex genital ulcer real-time PCR multiplex assay for detecting Treponema pallidum, herpes simplex virus 1 (HSV-1) and 2 (HSV-2), and Chlamydia trachomatis serovar L (lymphogranuloma venereum [LGV]) DNA in mucosal and genital ulcers in the context of suspected syphilis. In total, 374 documented genital and mucosal ulcers from patients with and without syphilis presenting at several sexually transmitted infection (STI) centers in France from October 2010 to December 2016 were analyzed at the National Reference Center (CNR) for Bacterial STIs at Cochin Hospital in Paris. T. pallidum subsp. pallidum detection results were compared with the final diagnosis based on a combination of clinical examination, serological results, and in-house nested PCR (nPCR). Detections of HSV and LGV were validated against reference methods. We found that 44.6% of the 374 samples tested were positive for T. pallidum subsp. pallidum, 21% for HSV, and 0.8% for LGV. No positive results were obtained for 30.7% of samples, and 4.8% presented coinfections. For T. pallidum subsp. pallidum detection, the overall sensitivity was 80% (95% confidence interval [CI], 76.1 to 84.1%), specificity was 98.8% (95% CI, 97.7 to 99.9%), positive predictive value was 98.8% (95% CI, 97.7 to 99.9%) and negative predictive value was 80.2% (95% CI, 76.2 to 84.2%), with a rate of concordance with the reference method of 92.5% (k = 0.85). This PCR multiplex assay is suitable for T. pallidum subsp. pallidum detection in routine use and facilitates the simultaneous rapid detection of a broad panel of pathogens relevant in a context of suspected syphilis lesions.

Decomplexifying Serum and Cerebrospinal Fluid (CSF) Serologic Testing of Neurosyphilis: A Case Report of Ocular Syphilis and Highlights of the Principles of Serologic Testing

Serologic tests for syphilis can be quite complex. The screening and confirmatory tests, which number at least eight, are mathematically interpreted as a total of 16 possible combinations, if we choose one test from each of two sets of four. However, this bewildering complexity is simplified if we apply certain principles. We reiterate and propose four axioms. First, we distinguish between treponemal versus non-treponemal tests. The former, the treponemal test, is specific for the spirochete, treponema pallidum, and is used as a confirmatory test. It rarely declines over time. The latter, the non-treponemal test, is a screening test and reflects treponemal or tissue damage, is reported as a titer, and is used to monitor disease activity. We usually need both for screening and confirmatory diagnostic testing. Secondly, for rapid plasma reagin (RPR) tests, a non-treponemal serology test titer of at least 1:8 is suggestive of syphilis, but not necessarily neurosyphilis. A false-negative test usually registers below this dilution level and may be due to the "prozone phenomenon". Serum RPR titers are usually greater than 1:32. Thirdly, a negative treponemal test in the cerebrospinal fluid excludes neurosyphilis and a positive test is highly sensitive but lacks specificity, usually due to blood contamination. Most patients with neurosyphilis will have a positive non-treponemal test in the cerebrospinal fluid (CSF) with elevated protein and pleocytosis. Fourthly, a serological cure is defined as at least a four-fold decline in a non-treponemal test titer at three and six months, or a persistently low titer after treatment. Patients who do not fulfill these criteria are known as "serofast". We describe the case of a 38-year-old man with human immunodeficiency virus-type 1 who developed bilateral optic disc edema with photopsias and transient visual obscurations.

Genetic Determinants of Antibody-Mediated Immune Responses to Infectious Diseases Agents: A Genome-Wide and HLA Association Study

BACKGROUND

Infectious diseases are causally related to a large array of noncommunicable diseases (NCDs). Identifying genetic determinants of infections and antibody-mediated immune responses may shed light on this relationship and provide therapeutic targets for drug and vaccine development.

METHODS

We used the UK biobank cohort of up to 10 000 serological measurements of infectious diseases and genome-wide genotyping. We used data on 13 pathogens to define 46 phenotypes: 15 seropositivity case-control phenotypes and 31 quantitative antibody measurement phenotypes. For each of these, we performed genome-wide association studies (GWAS) using the fastGWA linear mixed model package and human leukocyte antigen (HLA) classical allele and amino acid residue associations analyses using Lasso regression for variable selection.

RESULTS

We included a total of 8735 individuals for case-control phenotypes, and an average (range) of 4286 (276-8555) samples per quantitative analysis. Fourteen of the GWAS yielded a genome-wide significant (P < 5 ×10-8) locus at the major histocompatibility complex (MHC) on chromosome 6. Outside the MHC, we found a total of 60 loci, multiple associated with Epstein-Barr virus (EBV)-related NCDs (eg, RASA3, MED12L, and IRF4). FUT2 was also identified as an important gene for polyomaviridae. HLA analysis highlighted the importance of DRB1*09:01, DQB1*02:01, DQA1*01:02, and DQA1*03:01 in EBV serologies and of DRB1*15:01 in polyomaviridae.

CONCLUSIONS

We have identified multiple genetic variants associated with antibody immune response to 13 infections, many of which are biologically plausible therapeutic or vaccine targets. This may help prioritize future research and drug development.

2020 European guideline on the management of syphilis

The 2020 edition of the European guideline on the management of syphilis is an update of the 2014 edition. Main modifications and updates include: -The ongoing epidemics of early syphilis in Europe, particularly in men who have sex with men (MSM) -The development of dual treponemal and non-treponemal point-of-care (POC) tests -The progress in non-treponemal test (NTT) automatization -The regular episodic shortage of benzathine penicillin G (BPG) in some European countries -The exclusion of azithromycin as an alternative treatment at any stage of syphilis -The pre-exposure or immediate post-exposure prophylaxis with doxycycline in populations at high risk of acquiring syphilis.

Immunization with nontreponemal antigen alters the course of experimental syphilis in the rabbit model

The role of nontreponemal antibodies in the Treponema pallidum infection course is unclear. We investigated the effect of immunization with nontreponemal antigen on T. pallidum-challenged rabbits. Nontreponemal antigen was injected intravenously into rabbits in the nontreponemal group (n = 12) to elicit antibodies (≥1:64), and normal saline-injected rabbits were used as controls (n = 12). Then, rabbits were challenged with 10⁶T. pallidum per site along their back. Lesion development was observed, and the injection sites were biopsied for mRNA analysis every week. Six rabbits from both groups were euthanized at 14 d and 28 d. The popliteal lymph nodes were extracted to assess infectivity using a rabbit infectivity test. The maximum lesion diameters were not different between the two groups (12.4 ± 0.9 mm in the nontreponemal group vs. 12.5 ± 1.0 mm in the control group, P = 0.386), but the time to maximum diameter appearance was delayed by approximately 4 d in the nontreponemal group (14.4 ± 1.6 d vs. 10.8 ± 1.9 d, P = 0.000). There were no significant differences in the proportions of lesions (58/60 (96.7%) vs. 59/60 (98.3%), P = 0.500) or ulcers (55/60 (91.7%) vs. 57/60 (95.0%), P = 0.359) between the two groups. An ulcer development delay of 5 d was observed in the nontreponemal group (19.3 ± 2.0 d vs. 14.0 ± 1.8 d, P = 0.000). IL-2 and IFN-γ mRNA expression in the nontreponemal group was significantly higher than that in the control group at 7 d and 14 d post-challenge. flaA mRNA expression and the rabbit infectivity test positive rate were not different between the two groups. Immunization with nontreponemal antigen altered the syphilis course in rabbits, resulting in delayed maximal lesion diameter and ulcer development, but it could not inhibit the spread of T. pallidum from primary lesion sites to viscera.

Syphilis in Pregnancy

Despite a national plan to eliminate syphilis by 2005, recent trends have reversed previously achieved progress in the United States. After a nadir between 2000 and 2013, rates of primary and secondary syphilis among women and congenital syphilis rose by 172% and 185% between 2014 and 2018, respectively. Screening early in pregnancy, repeat screening in the third trimester and at delivery among women at high risk, adherence to recommended treatment regimens, and prompt reporting of newly diagnosed syphilis cases to local public health authorities are strategies that obstetrician-gynecologists can employ to fight the current epidemic. In this report, clinical manifestations and management of syphilis in pregnancy are reviewed, and both traditional and reverse sequence screening algorithms are reviewed in detail in the context of clinical obstetrics.

A retrospective study on nested PCR detection of syphilis treponemes in clinical samples: PCR detection contributes to the diagnosis of syphilis in patients with seronegative and serodiscrepant results

Syphilis, caused by Treponema pallidum ssp. pallidum (TPA), is a persisting global health problem. Although syphilis diagnostics relies mainly on serology, serological tests have some limitations, and it is recommended that the final diagnosis be supported by additional tests. The purpose of this study was to analyze the relationship between serology and PCR in syphilis diagnostics. From the year 2004 to May 2019, a total of 941 samples were taken from 833 patients suspected of having syphilis, in Czech Republic. In all these samples, both nested PCR detection of TPA and serology testing were performed. Of the 941 samples, 126 were seronegative, 651 were seropositive, and 164 were serodiscrepant. Among seronegative samples (n = 126), 11 were PCR-positive (8.7%). Among seropositive samples (n = 651; i.e., samples positive for both non-treponemal and treponemal serology tests), 368 samples were PCR-positive (56.5%). The remaining 164 serodiscrepant samples included RPR negative and treponemal serological test-positive samples (n = 154) and a set of 10 RPR-positive samples negative in treponemal serological tests. While the first group revealed 73 PCR-positive samples (47.4%), the second revealed 5 PCR positive samples (50.0%). PCR detection rates were highest in primary syphilis, with lower rates in the secondary and undetermined syphilis stages. As shown here, the nested PCR can improve diagnostics of syphilis, especially in seronegative patients and in patients with discrepant serology.

Atypical manifestations of recent syphilis: study of 19 cases

Background

Syphilis is one of the most common diseases that start with genital ulcers. Aside from the initial, classic ulcerative lesion of syphilis, called hard chancre, atypical presentations are common, with erosions, erythema, edema, balanitis, and other dermatological manifestations. Associated with initial genital lesions, the presence of inguinal adenopathies is frequent, and the presence of hardened and painless lymphangitis on the dorsum of the penis is rare.

Objectives

To describe atypical penile manifestations in patients with early syphilis.

Methods

The present study reports patients who developed cord-like lesions on the penis.

Results

The study included 25 patients with cord-like lesions on the penis; in 19 of those, the diagnosis of syphilis was confirmed.

Study limitations

Small number of patients included.

Conclusions

In view of the findings of the present investigation, it is important to emphasize that all patients who present with cord-like lesions on the penis must undergo a rapid test for syphilis, VDRL, serologies for HIV viral hepatitis B and C and, whenever possible, histopathological and Doppler exams.

Improving the coverage and accuracy of syphilis testing: The development of a novel rapid, point-of-care test for confirmatory testing of active syphilis infection and its early evaluation in China and South Africa

BACKGROUND

Current point-of-care tests (POCT) for syphilis, based on the detection of Treponema pallidum (TP) total antibodies, have limited capacity in distinguishing between active and past/treated syphilis. We report the development and early evaluation of a new prototype POCT based on the detection of TP-IgA antibodies, a novel biomarker for active syphilis.

METHODS

The TP-IgA POCT (index test) was developed in response to the World Health Organisation (WHO) target product profile (TPP) for a POCT for confirmatory syphilis testing. Two sub-studies were conducted consecutively using 458 pre-characterised stored plasma samples in China (sub-study one, addressing the criteria for the WHO TPP), and 503 venous blood samples collected from pregnant/postpartum women in South Africa (sub-study two, addressing potential clinical utility). Performance of the index test was assessed against standard laboratory-based serology using a combination of treponemal (TPHA) and non-treponemal (rapid plasma reagin [RPR]) tests.

FINDINGS

In sub-study one, the index test demonstrated 96·1% (95%CI=91·7%-98·5%) sensitivity and 84·7% (95%CI=80·15-88·6%) specificity for identification of active syphilis (TPHA positive, RPR positive). It correctly identified 71% (107/150) samples of past-treated syphilis (TPHA positive, RPR negative). In sub-study two, the index test achieved 100% (95%CI=59%-100%) sensitivity for active syphilis and correctly identified all nine women with past syphilis.

INTERPRETATION

The TP-IgA POCT has met the WHO TPP for a POCT for diagnosis of active syphilis and demonstrated its potential utility in a clinical setting. Future studies are warranted to evaluate field performance of the final manufactured test.

FUNDING

Saving Lives at Birth: Grand Challenge for Development, Thrasher Research Fund, and the Victorian Government Operational Infrastructure Scheme.

Performance of Treponema pallidum recombinant proteins in the serological diagnosis of syphilis

Syphilis serodiagnosis is challenging because distinct clinical forms of the infection may influence serological performance and discordant results between tests make clinical decisions difficult. Several recombinant Treponema pallidum-proteins have already been tested for syphilis diagnosis and they are critical to achieve high accuracy in serological testing. Our aim was to assess the varied from performance of T. pallidum-recombinant proteins TmpA, TpN17 and TpN47 for syphilis serodiagnosis. The proteins were evaluated using sera of 338 T. pallidum-negative, 173 T. pallidum-positive individuals and 209 sera from individuals infected with unrelated diseases. The diagnostic potential was validated by analysis of ROC curves. In the liquid microarray analyses, the ROC curve varied from 99.0% for TmpA and TpN17 to 100% for TpN47. The sensitivity score yielded values of up to 90% for TpN17, 100% for TpN47 and 80.0% for TmpA. The lowest and highest specificity values were presented by TpN47 (91.9%) and TmpA antigens (100%), respectively. TpN47 showed the highest accuracy score (95.5%) among all the recombinant proteins assayed. For the ELISA, the ROC curve was 97.2%, 91.8% and 81.6% for TpN17, TmpA and TpN47, respectively. TpN17 and TmpA yielded a sensitivity of 69.9%, while TpN47 obtained a value of 53.8%. Specificity was almost 100% for all three proteins. No cross-reaction was observed for TpN17 in the serum samples from non-bacterial infections. Regarding leptospirosis-positive samples, cross-reactivity score was varied from 8.6 to 34.6%. This is most probably due to conservation of the epitopes in these proteins across bacteria. The use of recombinant proteins in immunoassays for syphilis diagnosis was showed provide greater reliability to results of the treponemal assays. Despite the low sensitivity, the proteins showed high diagnostic capacity due to the AUC values found. However, an improvement in sensitivity could be achieved when antigenic mixtures are evaluated.

Serosurvey of Treponema pallidum infection among children with skin ulcers in the Tarangire-Manyara ecosystem, northern Tanzania

BACKGROUND

The first yaws eradication campaign reduced the prevalence of yaws by 95%. In recent years, however, yaws has reemerged and is currently subject to a second, ongoing eradication campaign. Yet, the epidemiological status of Tanzania and 75 other countries with a known history of human yaws is currently unknown. Contrary to the situation in humans in Tanzania, recent infection of nonhuman primates (NHPs) with the yaws bacterium Treponema pallidum subsp. pertenue (TPE) have been reported. In this study, we consider a One Health approach to investigate yaws and describe skin ulcers and corresponding T. pallidum serology results among children living in the Tarangire-Manyara ecosystem, an area with increasing wildlife-human interaction in northern Tanzania.

METHODS

To investigate human yaws in Tanzania, we conducted a cross-sectional study to screen and interview skin-ulcerated children aged 6 to 15 years, who live in close proximity to two national parks with high numbers of naturally TPE-infected monkeys. Serum samples from children with skin ulcers were tested for antibodies against the bacterium using a treponemal (Treponema pallidum Particle Agglutination assay) and a non-treponemal (Rapid Plasma Reagin) test.

RESULTS

A total of 186 children aged between 6 and 15 years (boys: 10.7 ± 2.1 (mean ± SD), N = 132; girls: 10.9 ± 2.0 (mean ± SD), N = 54) were enrolled. Seven children were sampled at health care facilities and 179 at primary schools. 38 children (20.4%) reported active participation in bushmeat hunting and consumption and 26 (13.9%) reported at least one physical contact with a NHP. None of the lesions seen were pathognomonic for yaws. Two children tested positive for treponemal antibodies (1.2%) in the treponemal test, but remained negative in the non-treponemal test.

CONCLUSIONS

We found no serological evidence of yaws among children in the Tarangire-Manyara ecosystem. Nevertheless, the close genetic relationship of human and NHPs infecting TPE strains should lead to contact prevention with infected NHPs. Further research investigations are warranted to study the causes and possible prevention measures of spontaneous chronic ulcers among children in rural Tanzania and to certify that the country is free from human yaws.

Evaluation of a Rapid Syphilis Test in an Emergency Department Setting in Detroit, Michigan

BACKGROUND

Syphilis transmission can be prevented by prompt diagnosis and treatment of primary and secondary infection. We evaluated the performance of a point-of-care rapid syphilis treponemal (RST) test in an emergency department (ED) setting.

METHODS

Between June 2015 and April 2016, men aged 18 to 34 years seeking services in a Detroit ED, and with no history of syphilis, were screened for syphilis with the RST test, rapid plasma reagin (RPR) test, and Treponema pallidum particle agglutination assay (TP-PA). A positive reference standard was both a reactive RPR and a reactive TP-PA. We compared test results in self-reported men who have sex with men (MSM) to non-MSM.

RESULTS

Among 965 participants, 10.9% of RST tests were reactive in MSM and only 1.5% in non-MSM (P < 0.001). Sensitivity of the RST test was 76.9% and specificity was 99.0% (positive predictive value, 50.0%) compared with the positive reference standard. Three discordant specimens found negative with the RST test but positive with the reference standard had an RPR titer of 1:1, compared with 10 specimens with concordant positive results that had a median RPR titer of 1:16. The RST sensitivity was 50.0% (positive predictive value, 68.4%) compared to the TP-PA test alone. Among men seeking care in an ED, the RST detected 76.9% of participants with a reactive RPR and TP-PA.

CONCLUSIONS

The RST test detected all of the participants with an RPR titer ≥1:2 but less than 20% of participants with a positive TP-PA and negative RPR. The RST test was useful to detect a high proportion of participants with an active syphilis in an urban ED.

Evaluation of the fully automated AIX1000 rapid plasma reagin system compared to a manual plasma reagin testing method for the diagnosis of syphilis

The analytical performance of the FDA-cleared AIX1000 automated RPR testing platform was evaluated in comparison to manual RPR card testing. Eight hundred thirty-three patient serum samples were analyzed, 87 samples were positive by the AIX1000, 108 were positive by the manual test method; overall agreement between methods was 96.5% (κ = 0.83). Cases were further classified by clinical and laboratory-based confirmation of disease, to which reactivity rates were compared, yielding sensitivities of 96.4% and 100%, and specificities of 99.2% and 96.8% for the automated and manual RPR methods, respectively. The difference in specificity between methods was statistically significant (P < 0.001). Twenty-five of 29 samples with discordant results were reactive by manual testing (titers of 1:1 or 1:2); 21 of 25 patients with negative AIX100 results were identified to have histories of remote, treated syphilis. Overall, the AIX1000 platform demonstrated excellent agreement with the manual RPR method; discrepancies occurred with specimens at the threshold of reactivity.

Performance of the Syphilis Health Check in Clinic and Laboratory-Based Settings

A study to evaluate clinical and laboratory performance of the Syphilis Health Check, found improved sensitivity when testing with whole blood compared to serum, in detecting likely active syphilis.

Background

In this study, we evaluate the performance of the Syphilis Health Check (SHC) in clinical and laboratory settings using fingerstick whole blood and serum.

Methods

Fingerstick whole blood and serum specimens from adult patients (n = 562) without prior syphilis history presenting at 2 county health department STD clinics in North Carolina were tested. Fingerstick specimens were tested with the SHC in clinic, and serum specimens were tested at the North Carolina State Laboratory of Public Health with: (1) qualitative rapid plasma reagin, (2) treponemal EIA, and (3) SHC. Sensitivity and specificity were calculated with 95% confidence intervals.

Results

The fingerstick whole blood had a sensitivity of 100% (7 of 7) and specificity of 95.7% (531 of 555), compared with consensus reference testing (CRT) (rapid plasma reagin and EIA reactive), but a sensitivity of 50% (8 of 16), and specificity of 95.9% (523 of 546), when compared with the treponemal EIA. Both laboratory-based SHC on serum and whole-blood SHC performed similarly, compared with CRT, and the treponemal EIA alone. Twenty-four specimens SHC reactive on whole blood were nonreactive by CRT. In 8 of these 24 cases, STD clinic staff reported difficulty reading the test line for the SHC. Of the fingerstick whole-blood SHC reactive specimens, only 14 of 31 were also serum SHC reactive.

Conclusions

The SHC on whole blood appears to be sensitive at detecting patients likely to have syphilis and could be an option for testing among high-risk populations. However, given challenges in interpreting SHC test results, adequate training of persons performing testing and ongoing quality assurance measures are key.

Primary Syphilis in the Male Urethra: A Case Report

We documented urethral Treponema pallidum infection in a man with nongonococcal urethritis and a negative syphilis serology using broad-range bacterial polymerase chain reaction (PCR) and sequencing, targeted PCR, and immunofluorescence microscopy. He subsequently seroconverted for syphilis. Early syphilis may present as urethritis. Urethral T. pallidum shedding can occur before seroconversion.

Blood transfusion safety in the country of Georgia: collateral benefit from a national hepatitis C elimination program

BACKGROUND

In April 2015, the government of Georgia (country) initiated the world's first national hepatitis C elimination program. An analysis of blood donor infectious screening data was conducted to inform a strategic plan to advance blood transfusion safety in Georgia.

STUDY DESIGN AND METHODS

Descriptive analysis of blood donation records (2015-2017) was performed to elucidate differences in demographics, donor type, remuneration status, and seroprevalence for infectious markers (hepatitis C virus antibody [anti-HCV], human immunodeficiency virus [HIV], hepatitis B virus surface antigen [HBsAg], and Treponema pallidum). For regression analysis, final models included all variables associated with the outcome in bivariate analysis (chi-square) with a p value of less than 0.05.

RESULTS

During 2015 to 2017, there were 251,428 donations in Georgia, representing 112,093 unique donors; 68.5% were from male donors, and 51.2% of donors were paid or replacement (friends or family of intended recipient). The overall seroprevalence significantly declined from 2015 to 2017 for anti-HCV (2.3%-1.4%), HBsAg (1.5%-1.1%), and T. pallidum (1.1%-0.7%) [p < 0.0001]; the decline was not significant for HIV (0.2%-0.1%). Only 41.0% of anti-HCV seropositive donors underwent additional testing to confirm viremia. Infectious marker seroprevalence varied by age, sex, and geography. In multivariable analysis, first-time and paid donor status were associated with seropositivity for all four infectious markers.

CONCLUSION

A decline during the study period in infectious markers suggests improvement in blood safety in Georgia. Areas that need further improvement are donor recruitment, standardization of screening and diagnostic follow-up, quality assurance, and posttransfusion surveillance.

Enzyme-linked immunosorbent assay (ELISA) versus Venereal Disease Research Laboratory test (VDRL) and rapid plasma reagin test (RPR) for screening of syphilis in pregnant women

OBJECTIVE

To evaluate a treponemal enzyme-linked immunosorbent assay (ELISA) as an alternative screening test for syphilis in pregnant women.

METHODS

A cross-sectional study of diagnostic test accuracy was carried out in a large volume laboratory from a tertiary care center. A total of 416 serum samples, including 102 archived syphilis Treponema pallidum hemagglutination (TPHA)-positive samples and 314 samples from pregnant women, were used to determine the sensitivity and specificity of ELISA. All the samples were subjected to Venereal Disease Research Laboratory (VDRL), rapid plasma reagin (RPR), ELISA, and TPHA tests. Performance characteristics of VDRL, RPR, and ELISA were calculated with TPHA as a reference standard test.

RESULTS

VDRL and RPR exhibited higher false positivity of 10.5% and 9.6%, respectively, compared to 2.5% by ELISA. The sensitivity and specificity of ELISA were 98% and 97.5%, of VDRL were 71.6% and 89.5%, and of RPR were 73.5% and 90.5%, respectively. Moreover, ELISA had an excellent agreement (kappa=0.9) with TPHA compared to VDRL/RPR which had a moderate agreement (kappa=0.6) only.

CONCLUSION

ELISA has the potential to replace VDRL/RPR as a screening test for syphilis in centers that can perform ELISA, especially for antenatal screening.

Update on Syphilis for Women's Health Nurses

After declining for many years, rates of syphilis in the United States are increasing. This article discusses possible reasons why women, and specifically pregnant women, are not getting tested properly. Lack of prenatal care, poor access to prenatal care, and improper prenatal care all have contributed to cases of congenital syphilis. Clinicians working in women's health care can address this issue by taking accurate sexual histories, remaining open to sexual fluidity among their patients, ensuring they are up to date on appropriate syphilis testing guidelines, and routinely offering screening to any woman at risk. Syphilis is a treatable and preventable sexually transmitted infection, and nurses, advanced practice nurses, and midwives can significantly contribute to reversing the current trend.

A fluorescent plasmonic biochip assay for multiplex screening of diagnostic serum antibody targets in human Lyme disease

Lyme disease (LD) diagnosis using the current two-tier algorithm is constrained by low sensitivity for early-stage infection and ambiguity in determining treatment response. We recently developed a protein microarray biochip that measures diagnostic serum antibody targets using grating-coupled fluorescent plasmonics (GC-FP) technology. This strategy requires microliters of blood serum to enable multiplexed biomarker screening on a compact surface and generates quantitative results that can be further processed for diagnostic scoring. The GC-FP biochip was used to detect serum antibodies in patients with active and convalescent LD, as well as various negative controls. We hypothesized that the quantitative, high-sensitivity attributes of the GC-FP approach permit: 1) screening of antibody targets predictive for LD status, and 2) development a diagnostic algorithm that is more sensitive, specific, and informative than the standard ELISA and Western blot assays. Notably, our findings led to a diagnostic algorithm that may be more sensitive than the current standard for detecting early LD, while maintaining 100% specificity. We further show that analysis of relative antibody levels to predict disease status, such as in acute and convalescent stages of infection, is possible with a highly sensitive and quantitative platform like GC-FP. The results from this study add to the urgent conversation regarding better diagnostic strategies and more effective treatment for patients affected by tick-borne disease.

A Metaphyseal Corner Fracture that Wasn't: A Case Report of Osteitis from Congenital Syphilis

CASE

Congenital syphilis (CS) is an infrequently seen condition in the United States; however, rates of CS have been on the rise. We present a case of an infant with a lesion of the radius that was initially diagnosed as a metaphyseal corner fracture and treated as such until maternal syphilis testing was noted to be positive. Ultimately, the child was diagnosed with CS. She is now undergoing treatment with penicillin and recovering well.

CONCLUSION

Although CS is rare, the incidence is on the rise and should remain on the differential of lytic lesions of bone in young children.

Seroprevalence of syphilis by VDRL test and biological false positive reactions in different patient populations: Is it alarming? Our experience from a tertiary care center in India

INTRODUCTION

Many centers for sexually transmitted infections in India perform only a single screening assay for diagnosis of syphilis which may yield biological false positive (BFP) reactions.

AIMS AND OBJECTIVE

The aim of this study was to determine the true picture of seroprevalence of syphilis and BFP reactions in different patient groups.

MATERIALS AND METHODS

A total of 57,308 serial serum samples obtained over a period of 5 years from different patient groups were screened by venereal disease research laboratory (VDRL) test both qualitatively and quantitatively. VDRL reactive sera were confirmed by Treponema pallidum hemagglutination (TPHA) test.

RESULTS

The overall seroprevalence of syphilis by VDRL test was 1.27%, and BFP rate in test population was 0.14%. The rate of BFP reactions among total tested male (0.44%) and female (0.1%) patients differs significantly. Out of 733 VDRL reactive samples, 81 were BFP, i.e., BFP reaction is occurring at a frequency of 11% of the total VDRL reactive samples (ratio of 8:1 for true positives/BFP). Similarly, among antenatal cases, almost 24% of the total VDRL reactive samples were BFP, or for every 116 true positives, there were 37 (almost one-third) BFP.

CONCLUSION

Although the overall seroprevalence of syphilis is low; the frequency of occurrence of BFP reactions is quite alarming. Hence, treponemal test must be used for confirmation of VDRL reactive sera.

Viral, bacterial, and fungal infections of the oral mucosa: Types, incidence, predisposing factors, diagnostic algorithms, and management

For millions of years, microbiota residing within us, including those in the oral cavity, coexisted in a harmonious symbiotic fashion that provided a quintessential foundation for human health. It is now clear that disruption of such a healthy relationship leading to microbial dysbiosis causes a wide array of infections, ranging from localized, mild, superficial infections to deep, disseminated life-threatening diseases. With recent advances in research, diagnostics, and improved surveillance we are witnessing an array of emerging and re-emerging oral infections and orofacial manifestations of systemic infections. Orofacial infections may cause significant discomfort to the patients and unnecessary economic burden. Thus, the early recognition of such infections is paramount for holistic patient management, and oral clinicians have a critical role in recognizing, diagnosing, managing, and preventing either new or old orofacial infections. This paper aims to provide an update on current understanding of well-established and emerging viral, bacterial, and fungal infections manifesting in the human oral cavity.

Post-treatment serological changes in some patients with early syphilis exhibit a parabolic trend

Early syphilis accounts for a large proportion of patients with syphilis. Non- Treponema pallidum tests are commonly used to assess treatment effectiveness by analyzing the serological titer before treatment and six months after treatment. However, serological changes during the first three months after completion of treatment have not been completely understood. This prompted us to investigate whether serum titers of patients exhibit a continuous decrease post-treatment and to assess the trend of change in serological titer during this period. One hundred and seventy-three eligible patients with early syphilis were included in the analysis. Pre-treatment serological titers and those at three and six months post-treatment were compared and analyzed. Serological recovery was defined as a 4-fold or greater decrease in titer from pre-treatment level. Forty patients (23.1%) were found to have an increased serum titer at three months after treatment. Among the 40 patients, 13 patients had primary syphilis, 5 patients had secondary syphilis, and 22 patients had early latent syphilis. The proportion of patients with primary syphilis was higher, and their initial titers were significantly lower. No significant differences were observed with respect to age, gender, or initial treatment. The assessment results of 17 patients (9.8% of the total patients) change. Serological changes in some patients exhibit a parabolic pattern that may affect the clinician’s assessment of patient recovery. Therefore, more frequent assessment of serological titer might be required within the first six months post-treatment.

Diagnostic Pitfalls in a Man with Systemic Lupus Erythematous

Systemic lupus erythematosus (SLE) is a chronic multi-systemic immune-mediated disease with confusing symptoms and delayed diagnosis. We report the case of a 32-year-old man with a persistent Venereal Disease Research Laboratory (VDRL)-positive reaction treated for syphilis 5 years previously, who was admitted for rash, weight loss, pancytopenia, inflammatory syndrome, and an important spontaneous prolongation of activated partial thromboplastin time (aPTT). Antiphospholipid antibodies were identified in the patient and he was diagnosed with SLE. The unrecognized false positive VDRL reaction and the delayed diagnosis of SLE were harmful as the patient had developed renal and cardiac complications by the time of diagnosis.

LEARNING POINTS

VDRL positive reaction as a diagnostic tool for syphilis must be confirmed by other tests like TPHA and Western Blot reaction, especially in the absence of a clinical context, taking into account the possibility of false positive results.Spontaneous prolongation of aPTT can be related to the presence of antiphospholipid antibodies.In medical practice, the clinician must always consider the uniqueness of a diagnosis that integrates all the clinical and laboratory data, even if the associations might seem confusing.

Is repeated retreatment necessary for HIV-negative serofast early syphilis patients?

A persistent non-treponemal serological response can be observed in patients with syphilis after treatment and is referred to as serofast. This status makes it difficult for clinicians to judge the curative effect of treatment, particularly in patients with early syphilis. In the present study, a total of 114 eligible serofast patients treated between January 2009 and June 2016 were retrospectively analyzed. All patients were subjected to rapid plasma reagin (RPR) serological tests and followed up for 24 months. The patients who remained serofast after initial therapy were given the first retreatment, and at 12 months, those who were still serofast received a second retreatment. After the first retreatment (6 months), 33.3% of the subjects (38/114) were serologically cured (≥4-fold decline in RPR titer). At 24 months, the patients that had achieved serological cure accounted for 23.7% (18/76) of the patients that received the second retreatment. Furthermore, 26.3% of subjects that achieved serological cure (10/38) and had not been further treated after the first retreatment spontaneously presented with a ≥4-fold decline in RPR titer or negative status. In conclusion, the present study indicated that in patients with early syphilis and serofast status after initial treatment, retreatments may not provide any significant benefit. The second retreatment did not significantly improve the patient's serological cure rate. There is no evidence that patients with early syphilis and serofast should receive multiple retreatments, in spite of this being commonly performed in clinical practice.

Development of a syphilis serum bank to support research, development, and evaluation of syphilis diagnostic tests in the United States

The Centers for Disease Control and Prevention’s (CDC) Division of STD Prevention, in collaboration with the Association of Public Health Laboratories (APHL), is developing a nationally available syphilis serum repository for research of Food and Drug Administration (FDA)-cleared or investigational syphilis diagnostic assays in the United States. State and local public health laboratories (PHL) submitted de-identified residual sera with information on collection date, volume, storage conditions, freeze-thaw cycles, PHL serology results, reported syphilis stage and demographic details if available. Previous test results were blinded and sera (N=152 reported syphilis stage, N = 131 unknown status) were tested at CDC using five FDA-cleared and one investigational syphilis tests. Treponemal and nontreponemal test sensitivity ranged from 76.3–100% and 63.2–100%, respectively, among staged specimens. The conventional treponemal assays showed high concordance of 95.4%. By providing syphilis stage and comprehensive serological test data, developed repository may serve as a valuable resource for diagnostic test validation studies.

Evaluation of Blood Transfusion Services in Public and Private Blood Bank Centers, Sana'a Capital, Yemen

The aim of this study was to evaluate blood transfusion services (BTS) at the main blood banks (BBs) of the Sana'a Capital. The 4 main BBs at Sana'a Capital were evaluated according to the safe World Health Organization BTS standards. Qualitative and quantitative data were collected using semi-structured questionnaires covering 6 components: activities, quality assurance system (QAS) and training, donation, grouping and compatibility testing, components, and screening for transfusion-transmitted infections (TTIs). An overall mean percent score for BTS was calculated where <60% is considered unsatisfactory, 60% to 79.9% satisfactory, and ≥80% highly satisfactory. The 4 BBs screen for HIV, hepatitis B, and hepatitis C and perform all functions except therapeutic transfusion. While 75% of the staff in BBs had received training in biosafety and half of the staff had received training in Standard Operating Procedures (SOPs), no QAS in place at any of the 4 BBs. The 4 BBs depended on 71% of their transfusions on family donors. Two BBs do not perform reverse grouping and do not keep patient/donor samples for the required minimum 5 days. Only one BB achieved an overall high satisfactory score and one achieved a satisfactory score. Findings highlight the increasing challenges facing BTS in Sana'a Capital especially the lack of therapeutic transfusion, poor QAS, and predominant dependence on the family donors. Therefore, there is a need to develop and train staff on QAS and to increase awareness among public on importance of voluntary donation. A wider scale evaluation of BTS in Sana'a is recommended.

Reactor Grids for Prioritizing Syphilis Investigations: Are Primary Syphilis Cases Being Missed?

BACKGROUND

Health departments prioritize investigations of reported reactive serologic tests based on age, gender, and titer using reactor grids. We wondered how reactor grids are used in different programs, and if administratively closing investigations of low-titer tests could lead to missed primary syphilis cases.

METHODS

We obtained a convenience sample of reactor grids from 13 health departments. Interviews with staff from several jurisdictions described the role of grids in surveillance and intervention. From 5 jurisdictions, trends in reactive nontreponemal tests and syphilis cases over time (2006-2015) were assessed by gender, age, and titer. In addition, nationally-reported primary syphilis cases (2013-2015) were analyzed to determine what proportion had low titers (≤1:4) that might be administratively closed by grids without further investigation.

RESULTS

Grids and follow-up approaches varied widely. Health departments in the study received a total of 48,573 to 496,503 reactive serologies over a 10-year period (3044-57,242 per year). In 2006 to 2015, the number of reactive serologies increased 37% to 169%. Increases were largely driven by tests for men although the ratios of tests per reported case remained stable over time. Almost one quarter of reported primary syphilis had low titers that would be excluded by most grids. The number of potentially missed primary syphilis cases varied by gender and age with 41- to 54-year-old men accounting for most.

CONCLUSIONS

Reactor grids that close tests with low titers or from older individuals may miss some primary syphilis cases. Automatic, computerized record searches of all reactive serologic tests could help improve prioritization.

Origin of Nontreponemal Antibodies During Treponema pallidum Infection: Evidence From a Rabbit Model

The origin of nontreponemal antibodies during syphilis infection is hotly debated. Here, we analyzed the immune response in rabbits immunized with various antigens. Inactivated treponemes elicited the production of low-titer nontreponemal antibodies in some rabbits. Cardiolipin combined with bovine serum albumin also induced anticardiolipin antibody production. These findings indicate that Treponema pallidum contained a cardiolipin antigen with weak immunogenicity. However, active T. pallidum induced higher nontreponemal antibody production with strong immunogenicity at an earlier time point, and the antibody titer was consecutive, suggesting the high nontreponemal antibody titer resulted from the combined effects of both the T. pallidum cardiolipin antigen and the damaged host-cell cardiolipin antigen during syphilis infection, the latter of which plays a major role in the induction of nontreponemal antibody production. Our study provides direct animal evidence of the origin of nontreponemal antibodies during T. pallidum infection.