Long-bone radiographic abnormalities as a sign of active congenital syphilis in asymptomatic newborns.

Metaphyseal abnormalities are present in greater than 90% of infants with symptomatic congenital syphilis. The incidence of these lesions in asymptomatic newborns in the present epidemic is not known. To determine the incidence of bone lesions at birth in asymptomatic congenital syphilis, long-bone films were obtained for all babies born during a 9-month period with a positive perinatal serology. Of 2544 newborns, 61 had a positive maternal serology and 40 also had a positive cord serology. Two symptomatic babies had abnormal radiographs and 12 of 59 asymptomatic newborns had metaphyseal changes consistent with congenital syphilis. It is concluded that long-bone radiographs are abnormal in approximately 20% of asymptomatic newborns with positive perinatal treponemal serology. With the increasing incidence of congenital syphilis, radiologic studies should be included in the assessment of all newborns with a positive serology. Indeed, those patients with any sign of active disease should be carefully followed because even treated infants remain at some risk for developing the late sequelae of congenital syphilis.