Section 4: Spirochetal, Protozoal, Mycobacterial, and Rickettsial Diseases

Congenital syphilis In utero infection by the spirochete Treponema pallidum can occur after the 16th week of gestation. Intrauterine disease, especially during early pregnancy, may result in spontaneous abortion or in a severely affected infant. Severe disease that is present at birth presents with hepatosplenomegaly, ascites, meningoencephalitis, and severe anemia. Osteochondritis is the most characteristic bone change. The cutaneous findings in severe congenital syphilis include bullae, pustules, macules, and papules.

Fissuring and peeling of the skin are also characteristic. The palms, soles, and periorificial skin are sites of predilection. Syphilitic rhinitis, with a copious and bloody nasal discharge, is an associated finding. If infection occurs late in pregnancy, signs and symptoms may be delayed for several weeks. In these cases, diagnosis is usually made on the basis of a positive syphilis serology in mother and infant. If the disease is allowed to progress, rhinitis, cutaneous macules, and mucous patches may be the presenting signs.

Acquired syphilis Unlike congenital syphilis, acquired syphilis in infants, children, and adolescents follows the classic course of syphilis in adults. Such an infection in a child should be assumed to be the result of sexual abuse. The first event in the development of syphilis is a dark-field positive chancre at the portal of entry of the treponeme. Shortly thereafter, serologic tests for syphilis become positive.

Secondary syphilis usually develops 6 to 8 weeks after the appearance of the chancre. Malaise, low-grade fever, myalgias, and lymphadenopathy are accompanied by a wide variety of cutaneous manifestations. The lesions shown in Fig. 4-3 are condylomata lata around the rectum. Note the moist papules and plaques. Figure 4-4 shows the most common presentation: copper-colored papulosquamous lesions, most commonly on the palms and soles.

Acquired syphilis Sometimes the eruption resembles pityriasis rosea, as seen in Fig. 4-5. Other cutaneous manifestations of secondary syphilis include papular lesions, pustules, nodules, and plaques.

Mucous patches are a common manifestation of acquired syphilis, and appear as white slightly raised plaques on an erythematous base with a serpentine, well-defined border.

Yaws This is a nonvenereal treponematosis that is caused by T pertenue. It is endemic in areas of Central and South America, Africa, and Southeast Asia. The disease is acquired by physical contact, and the majority of cases occur during childhood. An ulceration occurs at the site of the primary inoculation. ...