Syphilis in Dermatology: Recognition and Management

Development of toluidine red particle agglutination-based turbidimetric immunoassay for anticardiolipin antibody detection in syphilis

INTRODUCTION

Serological tests of non-treponemal and treponemal types are the most frequently used for syphilis diagnosis. Nontreponemal tests are used to monitor disease activity. Toluidine red unheated serum test (TRUST), as one of nontreponemal tests, is generally applicable to hospitals at different levels. However, accurate judgment of TRUST results is inseparable from an experienced and accurate operator. To reduce current shortcomings of manual TRUST method, we attempted to convert the manual TRUST test into automatic TRUST test, that is, to determine the degree of aggregation of toluidine red particles by detecting the absorbance value of serum after reaction with toluidine red particles.

METHODS

50 μL of serum sample and 80 μL toluidine red particles were added to 96-well plate. Then, the 96-well plate was placed on a microplate reader at medium grade for 8 min to mix. Then, plasma reagin reacted with toluidine red particles and promoted the aggregation of toluidine red particles to form a large clot, which eventually caused a decrease in the absorbance at 540 nm.

RESULTS

The results showed that the specificity of the automatic TRUST test was 100%, the sensitivity was 87%. And this method showed 93.5% correlation with manual TRUST test. The developed method is simple and involves less subjectivity in reading results, opening new avenues for syphilis diagnostic testing.

CONCLUSION

Turbidimetric immunoassay can avoid the shortcomings of subjective interpretation, time-consuming and manual operation of manual TRUST method, and is more suitable for large-scale screening in health examination.

Two-Stage Syphilis Testing

A 54-year-old woman presented with erythematous annular and indurated plaques on her face, trunk, and extremities and had false-positive syphilis test results during 2 pregnancies 25 and 22 years prior. What would you do next?

A case of syphilitic balanitis of Follman in a circumcised patient-Don't be fooled! A case report

Syphilis is known as the great masquarader. We describe a case of a young patient with an atypical chancre.

[Translated article] AEDV Expert Consensus Document on the Organization of a Multidisciplinary Unit for Patients With or at Risk of Venereal Infections

Over the past few years, venereal or sexually transmitted infections (STIs) have been on the rise worldwide requiring additional specialized monographic consultations to specifically treat STIs. Therefore, the Spanish Academy of Dermatology and Venereology (AEDV) Research Working Group on STIs and HIV has drafted this document with the necessary requirements in terms of infrastructure, personnel, technology, specific materials for sample collection, and needs for current therapeutic options. Strict emphasis is placed on the protection of patient privacy. A health care circuit model is outlined too. Additionally, a section has been included on contact tracking and reporting, key elements for the effective prevention and control of STIs. These clinical practice guidelines seek to establish a clinical action framework adapted to the current challenges posed by STIs and HIV in the dermatology, venereology, and multidisciplinary settings.

Epidemiological characteristics of syphilis in mainland China, 2004 to 2019

OBJECTIVES

Syphilis is a globally prevalent sexually transmitted infection. This study aimed to elucidate the epidemiological characteristics of syphilis in China from 2004 to 2019.

METHODS

Incidence data for syphilis across 31 provinces in mainland China were obtained from the Data Center of China Public Health Science for the period from 2004 to 2019. Epidemiological methods and the Chi-squared test were used to analyze the temporal, regional, and disease stage distributions of syphilis.

RESULTS

In total, 5,527,399 syphilis cases were reported in China from 2004 to 2019, with an average annual prevalence of 25.7063 per 100,000 population and overall increasing trend. In terms of regional distribution, high-incidence provinces included Shanghai, Zhejiang, Fujian, Guangxi, Guangdong, Xinjiang, Ningxia, and Qinghai. The proportion of latent syphilis increased from 20.41% in 2004 to 82.95% in 2019, with an upward trend each year.

CONCLUSIONS

Syphilis incidence exhibited an overall increasing trend in China, and latent syphilis was predominant. Syphilis incidences considerably varied among regions, and syphilis was detected from coastal to inland provinces. Thus, syphilis prevention and control programs should be tailored according to the specific epidemiological characteristics of each region.

AEDV Expert Consensus Document on the Organization of a Multidisciplinary Unit for Patients With or at Risk of Venereal Infections

Over the past few years, venereal or sexually transmitted infections (STIs) have been on the rise worldwide requiring additional specialized monographic consultations to specifically treat STIs. Therefore, the Spanish Academy of Dermatology and Venereology (AEDV) Research Working Group on STIs and HIV has drafted this document with the necessary requirements in terms of infrastructure, personnel, technology, specific materials for sample collection, and needs for current therapeutic options. Strict emphasis is placed on the protection of patient privacy. A health care circuit model is outlined too. Additionally, a section has been included on contact tracking and reporting, key elements for the effective prevention and control of STIs. These clinical practice guidelines seek to establish a clinical action framework adapted to the current challenges posed by STIs and HIV in the dermatology, venereology, and multidisciplinary settings.

Treponema pallidum-induced prostaglandin E2 secretion in skin fibroblasts leads to neuronal hyperpolarization: A cause of painless ulcers

BACKGROUND

Primary syphilis is characterized by painless ulcerative lesions in the genitalia, the aetiology of painless remains elusive.

OBJECTIVES

To investigate the role of Treponema pallidum in painless ulcer of primary syphilis, and the mechanisms underlying painless ulcers caused by T. pallidum.

METHODS

An experimental rabbit model of primary syphilis was established to investigate its effects on peripheral nerve tissues. Human skin fibroblasts were used to examine the role of T. pallidum in modulating neurotransmitters associated with pain and to explore the signalling pathways related to neurotransmitter secretion by T. pallidum in vitro.

RESULTS

Treponema pallidum infection did not directly lead to neuronal damage or interfere with the neuronal resting potential. Instead, it facilitated the secretion of prostaglandin E2 (PGE2) through endoplasmic reticulum stress in both rabbit and human skin fibroblasts, and upregulation of PGE2 induced the hyperpolarization of neurones. Moreover, the IRE1α/COX-2 signalling pathway was identified as the underlying mechanism by which T. pallidum induced the production of PGE2 in human skin fibroblasts.

CONCLUSION

Treponema pallidum promotes PGE2 secretion in skin fibroblasts, leading to the excitation of neuronal hyperpolarization and potentially contributing to the pathogenesis of painless ulcers in syphilis.

AEDV Expert Consensus for the Management of Syphilis

Syphilis -the "great simulator" for classical venereologists-is re-emerging in Western countries despite adequate treatment; several contributing factors have been identified, including changes in sexual behaviour, which won't be the topic of this article though. In 2021, a total of 6613 new cases of syphilis were reported in Spain, representing an incidence of 13.9×100 000 inhabitants (90.5%, men). Rates have increased progressively since 2000. The clinical presentation of syphilis is heterogeneous. Although chancroid, syphilitic roseola and syphilitic nails are typical lesions, other forms of the disease can be present such as non-ulcerative primary lesions like Follmann balanitis, chancres in the oral cavity, patchy secondary lingual lesions, or enanthema on the palate and uvula, among many others. Regarding diagnosis, molecular assays such as PCR have been replacing dark-field microscopy in ulcerative lesions while automated treponemal tests (EIA, CLIA) are being used in serological tests, along with classical tests (such as RPR and HAART) for confirmation and follow-up purposes. The interpretation of these tests should be assessed in the epidemiological and clinical context of the patient. HIV serology and STI screening should be requested for anyone with syphilis. Follow-up of patients under treatment is important to ensure healing and detect reinfection. Serological response to treatment should be assessed with the same non-treponemal test (RPR/VDRL); 3-, 6-, 12-, and 24-month follow-up is a common practice in people living with HIV (PLHIV). Sexual contacts should be assessed and treated as appropriate. Screening is advised for pregnant women within the first trimester of pregnancy. Pregnant women with an abortion after week 20 should all be tested for syphilis. The treatment of choice for all forms of syphilis, including pregnant women and PLHIV, is penicillin. Macrolides are ill-advised because of potential resistance.

Through the Eyes: A Case of Ocular Syphilis

Syphilis is a bacterial disease caused by Treponema pallidum and is sexually transmitted via vaginal, anogenital, or orogenital contact. Vertical transmission between mother and unborn child is also possible, but transmission via skin-to-skin or blood contact is rare. The objective of this case is to highlight this rare ocular manifestation of syphilis as it manifests as a multisystemic disease affecting many organ systems. This is a case of a 46-year-old male with vision loss who was referred to the emergency department by an ophthalmologist. Two days before the presentation at the emergency department, the ophthalmologist observed the presence of optic disc edema in the left eye. At the emergency department, he complained of bright light spots in the left eye and complete darkness in the central aspect of the eyes. He reported having a non-pruritic erythematous rash on the anterior abdomen that began one week before his presentation at the emergency department. The patient also reported having multiple sexual partners. Physical examination findings showed a visual field defect in the left eye, normal bilateral eye movement, and a non-tender skin reticulation over the anterior abdominal wall. Lab results showed complete blood count (CBC) and comprehensive metabolic panel (CMP) within normal limits, fluorescent treponemal antibody (FTA) antibody reactive, human immunodeficiency virus (HIV) test and hepatitis panel negative, rapid plasma reagin (RPR) titer 1:64, and imaging results negative for any significant abnormalities. The infectious disease specialists were consulted, and the recommended IV penicillin of four million units every four hours was given. The patient reported an improvement in his blurry vision over three days. By six months, his vision was back to baseline. This case report is significant due to the rare occurrence of ocular complications as an initial presentation of syphilis. Considering the rising cases of syphilis in the United States, it is important to highlight the possibility of this uncommon clinical presentation of syphilis.