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Acute thrombosed external hemorrhoid. Young male suffered sudden onset of rectal pain and bleeding after a bowel movement. (Photo contributor: Lawrence B. Stack, MD.)

The authors wish to thank Diane M. Birnbaumer and Lynn K. Flowers for their contributions to prior editions.


Clinical Summary

Syphilis is a systemic illness caused by Treponema pallidum. The disease occurs in stages, with each stage having distinct physical findings. Primary syphilis is heralded by the development of a single lesion at the site of inoculation. This usually occurs within 2 to 6 weeks of exposure, but may take as long as 90 days. Patients often do not notice or seek care for the primary lesion. They may, however, present with a solitary, round, painless genital chancre or ulcer. The ulcer may also be slightly painful and multiple ulcers are sometimes seen. The base of the genital ulcer is typically dry in males and moist in females; purulent fluid in the base is uncommon. The borders of the ulcer are often indurated. Although genital ulcers are most common, ulcers may develop at any exposed site. Bilateral, nontender, nonfluctuant adenopathy is common. Without treatment, ulcers will resolve spontaneously within 3 to 12 weeks as the infection progresses to the secondary stage. Patients with primary syphilis are at risk for concurrent infection with other sexually transmitted infections.

Secondary syphilis involves systemic dissemination of T pallidum and manifests first with the development of diffuse, nonpruritic macules. The macules develop within 2 to 10 weeks after resolution of the primary ulcers. The macules later evolve into a maculopapular eruption with small, round or annular lesions and involve primarily the trunk, palms, and soles. Diffuse, painless lymphadenopathy is also seen at this stage. Mucous patches may develop on the tongue and buccal mucosa. Condyloma lata and patchy alopecia can also be seen during this stage. The manifestations of this stage resolve without treatment in several months. Despite resolution of the symptoms, untreated syphilis will persist in the body and may become latent or later manifest as tertiary syphilis, a discussion of which is beyond the scope of this text.

Management and Disposition

To confirm the diagnosis, check an RPR or VDRL. Also test the patient for HIV and other sexually transmitted infections such as Neisseria gonorrhea and Chlamydia. Parenteral penicillin G is the preferred treatment for every stage of syphilis. For primary or secondary syphilis, treat with a single dose of benzathine penicillin G, 2.4 million units, intramuscularly. Treat penicillin-allergic patients with either doxycycline 100 mg orally twice daily or tetracycline 500 mg orally four times daily for 14 days. Refer pregnant patients with penicillin allergy for desensitization and subsequent treatment with pen G as the ...

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