Seven infants with congenital syphilis who became symptomatic between 3 and 14 weeks of age are reported from the Bronx Municipal Hospital Center and Albert Einstein College of Medicine, Bronx, NY. At delivery four infants and their mothers had negative rapid-plasma-reagin tests for syphilis. The other three mothers had been seronegative and were not tested at delivery; two of their infants were seronegative at birth and one was not tested. When the infants became symptomatic all seven and the five mothers available for testing were seropositive for syphilis. A characteristic diffuse rash was the presenting symptom in four and three presented with fever and aseptic meningitis. All infants had multisystem disease evidenced by hepatosplenomegaly, increased aminotransferase and alkaline phosphatase levels, anemia, and monocytosis. All responded to parenteral penicillin. Radiological evidence of bone involvement was seen in three of six patients tested. Renal disease occurred in the youngest child, a three week old boy who had severe nephrosis. A Jarisch-Herxheimer reaction, consisting of a sudden elevation of temperature, occurred in all children within two to six hours after they received the first dose of antibiotics. 
COMMENT. At least in areas where the disease is prevalent, serologic tests for syphilis should be included in the evaluation of all febrile infants and especially if associated with aseptic meningitis, hepatomegaly, or hematologic abnormalities, even if previous tests for syphilis have been negative at birth. The incidence of syphilis has reached epidemic proportions in some areas. In New York the rate of primary or secondary syphilis in women rose only marginally between 1983 and 1986 but it increased almost four-fold between 1986 and 1988. In the same two year period the number of reported cases of congenital syphilis rose from 57 to 357. The pediatrician’s suspicion of congenital syphilis must remain high to avoid misdiagnosis.