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eMedicine Journal > Emergency Medicine > Infectious Diseases
Syphilis

Synonyms, Key Words, and Related Terms: Treponema pallidum, T pallidum, primary syphilis, secondary syphilis, early latent syphilis, late latent syphilis, tertiary syphilis, gummatous syphilis, cardiovascular syphilis, neurosyphilis, sexually transmitted diseases, STDs, advanced syphilis, chancre, genital chancre, inguinal adenitis, patchy alopecia, nonpatchy alopecia, condylomata lata, hepatitis, nephropathy, proctitis, arthritis, optic neuritis, endarteritis of the aorta, aortitis, aneurysm, Venereal Disease Research Laboratory test, VDRL test, syphilitic meningitis, meningovascular syphilis, parenchymatous neurosyphilis, ataxia, paresis, dementia
Author Information | Introduction | Clinical | Differentials | Workup | Treatment | Medication | Follow-up | Miscellaneous | Test Questions | Bibliography

AUTHOR INFORMATION Section 1 of 11    Click here to go to the top of this page Click here to go to the next section in this topic

Authored by Todd A McGregor, MD, Staff Physician, Department of Emergency Medicine, University of Southern California/Los Angeles County

Coauthored by Allison J Richard, MD, Instructor of Clinical Emergency Medicine, Keck School of Medicine, University of Southern California, Consulting Staff, Department of Emergency Medicine, Los Angeles County-University of Southern California Hospital; Bradley Pulver, MD, Assistant Director, Department of Emergency Medicine, Englewood Hospital and Medical Center

Todd A McGregor, MD, is a member of the following medical societies: American College of Emergency Physicians

Edited by Joseph J Sachter, MD, FACEP, Consulting Staff, Department of Emergency Medicine, Muhlenberg Regional Medical Center; Francisco Talavera, PharmD, PhD, Senior Pharmacy Editor, eMedicine; Eric L Weiss, MD, DTM&H, Director of Stanford Travel Medicine, Medical Director of Stanford Lifeflight, Assistant Professor, Departments of Emergency Medicine and Infectious Diseases, Stanford University School of Medicine; John Halamka, MD, Chief Information Officer, CareGroup Healthcare System, Assistant Professor of Medicine, Department of Emergency Medicine, Beth Israel Deaconess Medical Center; Assistant Professor of Medicine, Harvard Medical School; and Charles V Pollack, Jr, MD, MA, FACEP, Professor, Department of Emergency Medicine, University of Pennsylvania College of Medicine; Chairman, Department of Emergency Medicine, Pennsylvania Hospital

Author's Email:Todd A McGregor, MDClick here to view conflict-of-interest information on the author of this topic
Editor's Email:Joseph J Sachter, MD, FACEP 

eMedicine Journal, April 24 2006, VOLUME 7, Number 4
INTRODUCTION Section 2 of 11   Click here to go to the next section in this topic Click here to go to the top of this page Click here to go to the next section in this topic

Background: Syphilis is an infectious disease caused by the spirochete Treponema pallidum. It almost always is transmitted by sexual contact with infectious lesions, but it also can be transmitted in utero and via blood transfusion.

Syphilis has a myriad of presentations and can mimic many other infections and immune-mediated processes in advanced stages. Hence, it has earned the nickname "the great imposter." The complex and variable manifestations of the disease prompted Sir William Osler to remark that, "The physician who knows syphilis knows medicine."

Pathophysiology: T pallidum is a fragile spiral bacterium 6-15 micrometers long by 0.25 micrometers in diameter. It can survive only briefly outside of the body; thus transmission almost always requires direct contact with the infectious lesion(s).

T pallidum penetrates abraded skin or intact mucous membranes easily and disseminates rapidly, although asymptomatically, via the blood vessels and lymphatics.

The prominent histologic features of the human response to the presence of T pallidum are vascular changes with associated endarteritis and periarteritis. Additionally, chronic infection can result in granulomatous lesions called gummas.

The initial lesion of primary syphilis develops at the site of transmission after an incubation period of 10-90 days, with a mean of about 21-28 days, and then heals spontaneously in 3-7 weeks.

Secondary syphilis develops about 4-10 weeks after the appearance of the primary lesion and has a wide range of presentations. The most common systemic manifestations include malaise, fever, myalgias, and arthralgias with a generalized body rash and lymphadenopathy. These manifestations are termed the dermatitis-arthritis syndrome. During secondary infection, the immune reaction is at its peak and antibody titers are high.

Symptomatic secondary syphilis usually resolves without treatment. The disease then enters a latent stage that may be divided into early and late latent phases. Early latent syphilis is defined as follows: acquired syphilis within the preceding year, that is, (1) documented seroconversion; (2) unequivocal symptoms of primary or secondary syphilis; or (3) partner documented with primary, secondary, or early latent syphilis. Occasional relapses of active secondary lesions can occur. Late latent syphilis is defined as seroreactivity, in the absence of symptoms, greater than 2 years after inoculation. During the late latent stage, patients typically do not have infectious lesions. Tertiary syphilis is defined as seroreactivity greater than 2 years with symptoms. This can include all organ systems and, as alluded to earlier, manifests in many ways. As many as 40% of untreated infections can develop into tertiary disease.

Congenital syphilis is not addressed in this article.

Frequency:

Mortality/Morbidity: Mortality from syphilis can occur, but it is most likely due to complications of late disease. In this stage, death may result in approximately 20% of untreated patients.

Morbidity of primary and secondary syphilis ranges from the annoyance of the primary lesion to the more significant constitutional systemic symptoms of secondary syphilis. However, the progression to tertiary syphilis can result in serious permanent disability and sometimes death.

T pallidum is sensitive to penicillins and is easily treatable in the early stages.

Race: The disease still disproportionately affects black men, but the frequency of infections in blacks and whites has changed from, at one time 65:1 to currently 6:1 (black-to-white ratio).

The lowest incidence is among Native Americans.

Sex: Recent increases in incidence reflect new infections primarily among men. The ratio of male-to-female infections has risen from 1.2 in 1996 to 11.6 in 2004, suggesting that cases of men who have sex with men is primarily on the rise.

Some studies suggest that women with suspected sexually transmitted diseases (STDs) are screened for syphilis less often than men. This raises concerns about underdiagnosis in women.

High-risk groups include men having sex with men, inmates in correctional facilities, and those engaging in high-risk sexual activity.

Age: Syphilis is most common during the years of peak sexual activity. However, increased numbers of elderly persons are being diagnosed, presumably because of drugs that enable sexual activity among this age group.

CLINICAL Section 3 of 11   Click here to go to the next section in this topic Click here to go to the top of this page Click here to go to the next section in this topic

History: Since the manifestations of syphilis (particularly advanced syphilis) are nonspecific and may masquerade as many other diseases, the physician must keep a high index of suspicion regarding the possible diagnosis of syphilis during the workup.

The clinician should carefully reconstruct the time course and description of all symptoms and lesions and obtain a complete sexual history, including information about condom use and the number and symptomatology of all partners.

The United States Preventive Services Task Force (USPSTF) issued screening guidelines to include all pregnant women and people at risk of acquiring syphilis.

Physical: Conduct the physical examination with the manifestations of primary, secondary, and tertiary syphilis in mind. The lesions and exanthem of primary and secondary syphilis are infectious, thus, gloves must be worn.

DIFFERENTIALS Section 4 of 11   Click here to go to the next section in this topic Click here to go to the top of this page Click here to go to the next section in this topic

Chancroid
Condyloma Acuminata
Herpes Simplex
Lymphogranuloma Venereum
Pityriasis Rosea
Psoriasis
Stevens-Johnson Syndrome
Warts, Genital


Other Problems to be Considered:

Primary genital syphilitic lesion
Herpes simplex (primary and recurrent infection)
Chancroid
Traumatic superinfected lesions
Carcinoma
Mycotic infection
Granuloma inguinale
Lichen planus
Psoriasis
Fungal infection
Venereal chlamydial infections

Cutaneous eruption of secondary syphilis
Drug eruptions
Pityriasis rosea
Psoriasis
Lichen planus
Viral exanthem

WORKUP Section 5 of 11   Click here to go to the next section in this topic Click here to go to the top of this page Click here to go to the next section in this topic

Lab Studies:

Imaging Studies:

TREATMENT Section 6 of 11   Click here to go to the next section in this topic Click here to go to the top of this page Click here to go to the next section in this topic

Emergency Department Care: Base ED care on the symptoms of the individual patient. Most patients need only supportive care in the ED; however, a patient presenting with advanced neurosyphilis may require emergent intervention, including possible intubation. The current treatment for syphilis, from the Centers for Disease Control and Prevention 1993 STD treatment guidelines, is as follows; for dosage information, see Medication section.

Consultations: If the ED physician has concerns or questions about the patient's presentation or course, an infectious disease consultation is a reasonable course of action. Additionally, the CDC, WHO, and MMWR are an excellent updated references.
MEDICATION Section 7 of 11   Click here to go to the next section in this topic Click here to go to the top of this page Click here to go to the next section in this topic

The goal of pharmacotherapy is to eradicate the causative organism of syphilis, T pallidum. The drug of choice is parenteral penicillin G for all stages of syphilis. Since the dividing time of Tp is slow (days), penicillin G benzathine is the only penicillin effective for single-dose therapy because it is in depo form and levels remain therapeutic in the blood for up to 30 days. Avoiding Bicillin C-R (combination procaine and benzathine), which remains in blood for only 7 days, is essential.

Since T pallidum resistance to penicillin has not emerged, the primary need for alternative drugs in treating syphilis is reserved for penicillin-allergic patients. Alternative regimens recommended for penicillin-allergic patients are doxycycline, tetracycline, and erythromycin.

Although neither the tetracyclines nor erythromycin has been evaluated as extensively as penicillin G in the treatment of syphilis, some evidence suggests higher treatment failure rates in erythromycin-treated patients. Alternative treatment regimens should be used only in cases of documented penicillin allergy.

In a randomized controlled trial of 328 subjects with primary, secondary, or latent syphilis, the efficacy of a single, 2 g oral dose of azithromycin was compared to 2.4 million units of penicillin G benzathine intramuscularly. Although 52% of the study population were HIV seropositive, the cure rates were equivalent between the two drugs. Although encouraging, these results should not encourage the use of macrolides as a first-line agent because of increasing reports of macrolide resistance.

Drug Category: Antibiotics -- Empiric antimicrobial therapy must be comprehensive and should cover all likely pathogens in the context of the clinical setting.
Drug Name
Penicillin G benzathine (Bicillin) -- Interferes with synthesis of cell wall mucopeptide during active multiplication, resulting in bactericidal activity against susceptible microorganisms.
Adult DoseDisease for <1 year: 2.4 million U IM once in 2 injection sites
Disease for > 1 year: 2.4 million U in 2 injection sites weekly for 3 doses
Pediatric DoseDisease for <1 year: 50,000 U/kg IM once; not to exceed 2.4 million U/dose
Disease for > 1 year: 50,000 U/kg IM weekly for 3 doses; not to exceed 2.4 million U/dose
ContraindicationsDocumented hypersensitivity
Interactions Probenecid can increase effectiveness by decreasing clearance; tetracyclines can decrease effectiveness
Pregnancy B - Usually safe but benefits must outweigh the risks.
PrecautionsCaution in impaired renal function
Drug Name
Doxycycline (Vibramycin, Doryx) -- Inhibits protein synthesis and thus bacterial growth by binding with 30S and possibly 50S ribosomal subunits of susceptible bacteria.
Adult Dose300 mg/d PO in divided doses for 10 d
Pediatric Dose <8 years: Not recommended
>8 years: 2-5 mg/kg/d PO in 1-2 divided doses; not to exceed 200 mg/d
<100 lbs (45 kg): 2 mg/lb/d (4.4 mg/kg/d) divided bid
>100 lbs (45 kg): Administer as in adults
ContraindicationsDocumented hypersensitivity; severe hepatic dysfunction
InteractionsAntacids containing aluminum, calcium, magnesium, iron, or bismuth subsalicylate decrease bioavailability; can increase hypoprothrombinemic effects of anticoagulants; can decrease effects of oral contraceptives, causing breakthrough bleeding and increased risk of pregnancy
Pregnancy D - Unsafe in pregnancy
PrecautionsPhotosensitivity may occur with prolonged exposure to sunlight or tanning equipment; reduce dose in renal impairment; consider drug serum level determinations in prolonged therapy; exposure during tooth development (last half of pregnancy through age 8 y) can cause permanent discoloration of teeth; Fanconilike syndrome may occur with outdated tetracyclines
Drug Name
Tetracycline (Sumycin) -- Inhibits bacterial protein synthesis by binding with 30S and possibly 50S ribosomal subunit(s) of susceptible bacteria.
Adult Dose250-500 mg PO q6h
Mild to moderately severe infections: 500 mg PO bid or 250 mg qid for 7-14 d
Severe infections: 500 mg PO qid for 7-14 d
Pediatric Dose <8 years: Not recommended
>8 years: 10-20 mg/lb (25-50 mg/kg) PO qid
ContraindicationsDocumented hypersensitivity; severe hepatic dysfunction
InteractionsAntacids containing aluminum, calcium, magnesium, iron, or bismuth subsalicylate decrease bioavailability; can decrease effects of oral contraceptives, causing breakthrough bleeding and increased risk of pregnancy; can increase hypoprothrombinemic effects of anticoagulants
Pregnancy D - Unsafe in pregnancy
PrecautionsPhotosensitivity may occur with prolonged exposure to sunlight or tanning equipment; reduce dose in renal impairment; consider drug serum level determinations in prolonged therapy; exposure during tooth development (last half of pregnancy through age 8 y) can cause permanent discoloration of teeth; Fanconilike syndrome may occur with outdated tetracyclines
Drug Name
Erythromycin (Erythrocin, E-Mycin, EES) -- Indicated for treatment of infections caused by susceptible strains including T pallidum.
Adult Dose250 mg stearate/base (or 400 mg ethylsuccinate) PO q6h 1 h ac, or 500 mg q12h
Alternatively, use 333 mg PO q8h; increase up to 4 g/d depending on severity of infection
Pediatric Dose30-50 mg/kg/d (15-25 mg/lb/d) PO in divided doses; for severe infections, double dose
ContraindicationsDocumented hypersensitivity; hepatic impairment
InteractionsMay increase toxicity of theophylline, digoxin, carbamazepine, and cyclosporine; may potentiate anticoagulant effects of warfarin; lovastatin and simvastatin increase risk of rhabdomyolysis
Pregnancy B - Usually safe but benefits must outweigh the risks.
PrecautionsCaution in liver disease; estolate formulation may cause cholestatic jaundice; GI adverse effects are common (give doses pc); discontinue use if nausea, vomiting, malaise, abdominal colic, or fever occur
FOLLOW-UP Section 8 of 11   Click here to go to the next section in this topic Click here to go to the top of this page Click here to go to the next section in this topic

Further Outpatient Care:

Deterrence/Prevention:

Complications:

Prognosis:

Patient Education:

MISCELLANEOUS Section 9 of 11   Click here to go to the next section in this topic Click here to go to the top of this page Click here to go to the next section in this topic

Medical/Legal Pitfalls:

Special Concerns:

TEST QUESTIONS Section 10 of 11   Click here to go to the next section in this topic Click here to go to the top of this page Click here to go to the next section in this topic

CME Question 1: Which of the following best describes the characteristic presentation of primary syphilis?


A: Diffuse maculopapular rash, often involving the palms and soles, along with generalized lymphadenopathy
B: Multiple small painful ulcers on the genitalia
C: One or a few painful, shallow ulcers with ragged edges that bleed easily
D: Single painless ulcer with indurated edges and a firm consistency
E: Small, often barely noticeable, papule that resolves without ulceration

The correct answer is D: A single, painless ulcer with indurated edges and a firm consistency describes the presentation of primary syphilis. Answer A describes secondary syphilis; answer B is more consistent with genital herpes; answer C with chancroid; and answer E with the primary, often overlooked, lesion of lymphogranuloma venereum.

CME Question 2: Benzathine penicillin G, 2.4 million units IM as a single treatment (in penicillin-nonallergic patients), is effective for which of the following?


A: Primary syphilis
B: Secondary syphilis
C: Early latent syphilis ( <1 y duration)
D: A and B
E: A, B, and C

The correct answer is E: All 3 of these entities can be treated in a single-dose fashion. Alternatives to penicillin include a 2-week course of doxycycline, tetracycline, or erythromycin. Latent syphilis of greater than 1 year duration requires 3 consecutive weeks of this dose of penicillin.

Pearl Question 1 (T/F): Mucous patches are a genital lesion of secondary syphilis.

The correct answer is True: Mucous patches are superficial mucosal erosions, usually painless, that may develop on the tongue, oral mucosa, lips, vulva, vagina, and penis. Another manifestation of secondary syphilis is papules in intertriginous areas that may coalesce to form highly infectious lesions called condylomata lata.

Pearl Question 2 (T/F): The sensitivities of the nontreponemal tests (Venereal Disease Research Laboratory [VDRL] and rapid plasma reagent [RPR]) for primary and secondary syphilis are 40% and 60%, respectively.

The correct answer is False: The sensitivities of these tests are approximately 80% for primary and virtually 100% for secondary syphilis.

Pearl Question 3 (T/F): The recommended treatment for primary or secondary syphilis is 2.4 million units of procaine penicillin G intramuscularly.

The correct answer is False: Benzathine penicillin G, 2.4 million units intramuscularly as a single dose, is the recommended treatment.

Pearl Question 4 (T/F): A 24-year-old man is treated for secondary syphilis and returns a few hours later with severe malaise, chills, myalgias, and headache. The most likely etiology of these symptoms is an allergic reaction.

The correct answer is False: A Jarisch-Herxheimer reaction is the most likely cause. Treatment is supportive.
BIBLIOGRAPHY Section 11 of 11   Click here to go to the next section in this topic Click here to go to the top of this page

NOTE:
Medicine is a constantly changing science and not all therapies are clearly established. New research changes drug and treatment therapies daily. The authors, editors, and publisher of this journal have used their best efforts to provide information that is up-to-date and accurate and is generally accepted within medical standards at the time of publication. However, as medical science is constantly changing and human error is always possible, the authors, editors, and publisher or any other party involved with the publication of this article do not warrant the information in this article is accurate or complete, nor are they responsible for omissions or errors in the article or for the results of using this information. The reader should confirm the information in this article from other sources prior to use. In particular, all drug doses, indications, and contraindications should be confirmed in the package insert. FULL DISCLAIMER
eMedicine Journal, April 24 2006, VOLUME 7, Number 4
© Copyright 2001, eMedicine.com, Inc.

eMedicine Journals > Emergency Medicine > Infectious Diseases > Syphilis
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