Syphilis, one of the most common sexually-transmitted infections (STD) worldwide, is caused by a spirochete, Treponema pallidum, and the clinical course of syphilis is divided into four stages - primary, secondary, latent, and tertiary [1] [2] [3] [4]. Primary syphilis is the initial manifestation, characterized by the appearance of a painless papule eventually turning into an indurated ulcer on the skin or mucous membranes (known as the syphilitic chancre) [1] [5] [6] [7]. The chancre is seen at the initial site of bacterial inoculation, and the diameter of the lesion ranges from a few millimeters up to a few centimeters without exudate, although secondary infection can produce a purulent discharge from the lesion [4] [6]. Earlier syphilis occurred primarily in heterosexual men and women, however, now the incidence has increased amongst men having sex with men (MSM), with the glans penis being the most common site of the syphilitic chancre, usually after an incubation period of 10-90 days [3] [4] [6]. However, the lesion may appear at any site on the external genitalia, the anus, and perianal areas or in the oral cavity, and sometimes more than one chancre develops, especially in immunosuppressed individuals (such as those suffering from human immunodeficiency virus infection) [2] [4] [6]. Non-tender regional lymphadenopathy is often observed 1-2 weeks after the appearance of the typical skin lesion [1] [3] [4] [6]. In most patients, chancres resolve spontaneously after approximately 3-6 weeks, but lymphadenopathy may be present much longer [4].

• Unsafe Sexual Practices

  These are available for purchase online. not sharing sex toys avoiding alcohol and drugs that could potentially lead to unsafe sexual practices Having syphilis once does not mean a person is protected from it. [medicalnewstoday.com]

  Safer-sex messages should include reducing the number of sexual partners; knowing the health status and HIV infection status of partners; avoiding unsafe sexual practices, not just for HIV, but for all STDs; and using barrier protection methods such as [hivinsite.ucsf.edu]

• Inguinal Lymphadenopathy

  We report a case of primary syphilis presenting as erosive and crusted balanoposthitis with an underlying chancre, penile edema, and bilateral inguinal lymphadenopathy in a heterosexual man. [ncbi.nlm.nih.gov]

  Physical exam is significant for a diffuse, erythematous maculopapular rash, patchy alopecia on his scalp, wart-like white lesions on the base of his penis, and bilateral inguinal lymphadenopathy. VDRL and FTA-ABS were positive. [medbullets.com]

  Inguinal lymphadenopathy arises in men with ulcers on the genitals and cervical lymphadenopathy in patients with ulcers in the mouth. [dermnetnz.org]

• Perianal Ulcer

  Diseases Characterized by Genital, Anal, or Perianal Ulcers. Available online at . Accessed January 2013. Syphilis Testing Algorithms Using Treponemal Tests for Initial Screening --- Four Laboratories, New York City, 2005--2006. [labtestsonline.org]

• Tongue Ulcer

  Lips and tongue ulcers are the most frequently reported lesions and tonsillar ulcers are much more rare. We report the case of a 24-year-old woman with a syphilitic ulcer localized in her left tonsil. [ncbi.nlm.nih.gov]

• Tonsillar Ulcer

  Lips and tongue ulcers are the most frequently reported lesions and tonsillar ulcers are much more rare. We report the case of a 24-year-old woman with a syphilitic ulcer localized in her left tonsil. [ncbi.nlm.nih.gov]

• Mucocutaneous Rash

  Secondary syphilis Secondary syphilis may present in many different ways but usually includes a localized or diffuse mucocutaneous rash and generalized nontender lymphadenopathy. [emedicine.medscape.com]

• Chancroid

  The differential diagnosis includes ulcerative genital lesions such as chancroid, herpes progenitalis, aphthae (Behçet’s syndrome), and traumatic ulcers such as occur with biting. [dartmouth.edu]

  Lesions that can be confused with the chancre of primary syphilis include herpes simplex virus infection, chancroid, fixed drug eruption, lymphogranuloma venereum, granuloma inguinale (donovanosis), traumatic ulcer, furuncle (boil), and aphthous ulcer [aafp.org]

  […] typically heal spontaneously in 3 to 6 weeks, but also as quickly as 1 week or as slowly as 12 weeks Chancres increase the risk of acquiring HIV and other sexually transmitted diseases Anorectal chancres may resemble herpes simplex virus infection, chancroid [pathologyoutlines.com]

  […] hands and soles, pink to red macules Pityriasis – herald patch, macular, usually itchy Viral exanthems – most often with associated viral syndrome history Disseminated herpes simplex – usually vesicular, more painful Tinea versicolor Erythema multiforme Chancroid [clinicaladvisor.com]

• Syphilitic Chancre

  Six patients were seen with primary syphilitic chancres on their fingers between 1965 and 1980. Of these, two had bipolar chancres on their fingers and genitals resulting from sexual foreplay. [ncbi.nlm.nih.gov]

  Concepts Sign or Symptom ( T184 ) MSH D002601 ICD10 A51.0 SnomedCT 266127002, 58433006 English Chancre, Chancres, Syphilitic chancre, Syphilitic chancre NOS, Chancre [Disease/Finding], primary syphilis, chancre syphilitic, chancres, chancre, syphilis [fpnotebook.com]

  Extragenital syphilitic chancres. J Am Acad Dermatol 1986; 14:1094–1095. 4. Alessi E, Ghislanzoni M, Scioccati L, et al. PCR: A useful adjunct to the diagnosis of syphilis. Technical note preliminary results. [journals.lww.com]

  Primary syphilis is the initial manifestation, characterized by the appearance of a painless papule eventually turning into an indurated ulcer on the skin or mucous membranes (known as the syphilitic chancre). [symptoma.com]

  Syphilitic chancres are typically round, firm, and painless. Photograph credit: Centers for Disease Control and Prevention Public Health Image Library (Robert E. Sumpter, 1967). Figure 15. [std.uw.edu]

A detailed patient history and a proper physical examination can reveal sufficient data to make a presumptive diagnosis of syphilis in its primary stage. During the interview with the patient, physicians should assess sexual history, unprotected sex, multiple partners, etc.. and inspection and observation of typical skin lesions during physical examination could raise clinical suspicion. To confirm syphilis as the underlying cause, several diagnostic tests are available:

• Antibody testing - On the basis of their ability to detect T. pallidum antigens and respective antibodies in a direct or indirect fashion, two types of tests are described in the literature: Treponemal and non-treponemal. Detection of antibodies through a fluorescent treponemal antibody absorption assay (FTA-ABS), T. pallidum particle agglutination assay (TPPA), and T. pallidum hemagglutination assay (TPHA) are treponemal tests that yield reactive or non-reactive results in blood [2] [5] [6] [7]. On the other hand, Venereal Disease Research Laboratory (VDRL), rapid plasma reagin (RPR) and toluidine red unheated serum test (TRUST) are widely used three non-treponemal tests that measure the response of antibodies to cardiolipin [5] [7].
• Microscopy and other direct methods - Because serology testing does not provide a 100% positivity rate, especially in primary stages of the disease, spirochetal bacteria can be visualized with dark field microscopy, a specialized technique that necessitates the use of immunofluorescent stains, as T. pallidum is too thin to be visible on standard microscopy [3] [4][6] [7]. In addition, detection of bacterial genetic material through polymerase chain reaction (PCR) testing is another definite diagnostic method, but its cost and scarce availability are the main limitations [2] [5] [6].

• Rectal Biopsy Abnormal

  Spectrum of rectal biopsy abnormalities in homosexual men with intestinal symptoms. Gastroenterology 1986;91:651-9]. The number of reported cases of primary syphilis is increasing especially among this group of people [Goh BT. Syphilis in adults. [ncbi.nlm.nih.gov]

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7. Mattei PL, Beachkofsky TM, Gilson RT, Wisco OJ. Syphilis: a reemerging infection. Am Fam Physician. 2012;86(5):433-440.