Secondary Syphilis

Essentials of Diagnosis

• Generalized maculopapular skin rash.
• Mucous membrane lesions, including patches and ulcers.
• Weeping papules (condylomas) in moist skin areas.
• Generalized nontender lymphadenopathy.
• Fever.
• Meningitis, hepatitis, osteitis, arthritis, iritis.
• Many treponemes in scrapings of mucous membrane or skin lesions by immunofluorescence or darkfield microscopy.
• Serologic tests for syphilis always positive.

General Considerations & Treatment

The secondary stage of syphilis usually appears a few weeks (or up to 6 months) after development of the chancre, when sufficient dissemination of T pallidum has occurred to produce systemic signs (fever, lymphadenopathy) or infectious lesions at sites distant from the site of inoculation. The most common manifestations are skin and mucosal lesions. The skin lesions are nonpruritic, macular, papular, pustular, or follicular (or combinations of any of these types, but not vesicular), though the maculopapular rash is the most common. The skin lesions usually are generalized; involvement of the palms and soles is especially suspicious. Annular lesions simulating ringworm are observed in dark-skinned individuals. Mucous membrane lesions range from ulcers and papules of the lips, mouth, throat, genitalia, and anus ("mucous patches") to a diffuse redness of the pharynx. Both skin and mucous membrane lesions are highly infectious at this stage. Specific lesions - condylomata lata - are fused, weeping papules on the moist areas of the skin and mucous membranes.

Meningeal (aseptic meningitis or acute basilar meningitis), hepatic, renal, bone, and joint invasion may occur, with resulting cranial nerve palsies, jaundice, nephrotic syndrome, and periostitis. Alopecia (moth-eaten appearance) and uveitis may also occur.

The serologic tests for syphilis are positive in most cases. The cutaneous and mucous membrane lesions often show T pallidum on darkfield microscopic examination. A transient cerebrospinal fluid pleocytosis is seen in 30-70% of patients with secondary syphilis, though only 5% have positive serologic cerebrospinal fluid reactions. There may be evidence of hepatitis or nephritis (immune complex type). Circulating immune complexes exist in the blood and are deposited in blood vessel walls.

Skin lesions may be confused with the infectious exanthems, pityriasis rosea, and drug eruptions. Visceral lesions may suggest nephritis or hepatitis due to other causes. The diffusely red throat may mimic other forms of pharyngitis.

Treatment is as for primary syphilis unless central nervous system or ocular disease is present, in which case a lumbar puncture should be performed and, if positive, treatment is as for neurosyphilis (see below). Isolation of the patient is important.