Syphilis overview

Overview
Syphilis is a curable sexually transmitted disease caused by the Treponema pallidum spirochete. The route of transmission of syphilis is almost always by sexual contact, although there are examples of congenital syphilis via transmission from mother to child in utero. The signs and symptoms of syphilis are numerous; before the advent of serological testing, precise diagnosis was very difficult. In fact, the disease was dubbed the "Great Imitator" because it was often confused with other diseases, particularly in its tertiary stage. Syphilis (unless antibiotic-resistant) can be easily treated with antibiotics including penicillin. The oldest and still most effective method is an intramuscular injection of benzathine penicillin. If not treated, syphilis can cause serious effects such as damage to the heart, aorta, brain, eyes, and bones. In some cases these effects can be fatal. In 1998, the complete genetic sequence of T. pallidum was published which may aid understanding of the pathogenesis of syphilis.

Congenital syphilis
Further sub-classified depending on the different manifestations that occur depending on the stage of the disease.
 * Early
 * Late
 * Stigmata

Acquired syphilis

 * Primary syphilis
 * Secondary syphilis
 * Latent syphilis
 * Late/tertiary syphilis

Clinical Presentation

 * On the basis of clinical findings, the disease has been divided into a series of overlapping stages, which are used to help guide treatment and follow-up.
 * Persons who have syphilis might seek treatment for signs or symptoms of primary infection (i.e., ulcer or chancre at the infection site), secondary infection (i.e., manifestations that include, but are not limited to, skin rash, mucocutaneous lesions, and lymphadenopathy), neurologic infection (i.e., cranial nerve dysfunction, meningitis, stroke, acute or chronic altered mental status, loss of vibration sense, and auditory or ophthalmic abnormalities, which might occur through the natural history of untreated infection), or tertiary infection (i.e., cardiac or gummatous lesions).
 * Latent infections (i.e., those lacking clinical manifestations) are detected by serologic testing. Latent syphilis acquired within the preceding year is referred to as early latent syphilis; all other cases of latent syphilis are either late latent syphilis or latent syphilis of unknown duration.

Diagnosis

 * Darkfield examinations and tests to detect T. pallidum in lesion exudate or tissue are the definitive methods for diagnosing early syphilis.


 * Although no T. pallidum detection tests are commercially available, some laboratories provide locally developed PCR tests for the detection of T. pallidum.


 * A presumptive diagnosis of syphilis is possible with the use of two types of serologic tests:
 * nontreponemal tests (e.g., venereal disease research laboratory (VDRL) and rapid plasma reagent test) and
 * treponemal tests (e.g., fluorescent treponemal antibody absorbed (FTA-ABS) tests, the T. pallidum passive particle agglutination (TP-PA) assay, various enzyme immunoassays, and chemiluminescence immunoassays).


 * The use of only one type of serologic test is insufficient for diagnosis, because each type of test has limitations, including the possibility of false-positive test results in persons without syphilis.


 * False-positive nontreponemal test results can be associated with various medical conditions unrelated to syphilis, including autoimmune conditions, older age, and injection-drug use; therefore, persons with a reactive nontreponemal test should receive a treponemal test to confirm the diagnosis of syphilis.

Treatment

 * Penicillin G, administered parenterally, is the preferred drug for treating all stages of syphilis.


 * The preparation used (i.e., benzathine, aqueous procaine, or aqueous crystalline), the dosage, and the length of treatment depend on the stage and clinical manifestations of the disease.


 * Selection of the appropriate penicillin preparation is important, because T. pallidum can reside in sequestered sites (e.g., the CNS and aqueous humor) that are poorly accessed by some forms of penicillin.


 * Combinations of benzathine penicillin, procaine penicillin, and oral penicillin preparations are not considered appropriate for the treatment of syphilis.


 * During pregnancy, parenteral penicillin G is the only therapy with documented efficacy for syphilis. Pregnant women with syphilis in any stage who report penicillin allergy should be desensitized and treated with penicillin


 * The Jarisch-Herxheimer reaction is an acute febrile reaction


 * Frequently accompanied by headache, myalgia, fever, and other symptoms that usually occur within the first 24 hours after the initiation of any therapy for syphilis.


 * Patients should be informed about this possible adverse reaction.


 * The Jarisch-Herxheimer reaction occurs most frequently among patients who have early syphilis, presumably because bacterial burdens are higher during these stages.


 * Antipyretics can be used to manage symptoms, but they have not been proven to prevent this reaction.


 * The Jarisch-Herxheimer reaction might induce early labor or cause fetal distress in pregnant women, but this should not prevent or delay therapy.