[Intraurban differentials in congenital syphilis: a predictive analysis by neighborhood in the city of Rio de Janeiro, Brazil].

The study aimed to characterize notified cases of congenital syphilis from 2011 to 2014 in the city of Rio de Janeiro and to analyze possible associations between congenital syphilis and living conditions in the city's neighborhoods. Cases of congenital syphilis were characterized according to biological and socioeconomic variables and health services use. At the aggregate level, regression tree technique was used for the data analysis, with mean incidence rate (2011-2014) of congenital syphilis as the dependent variable and housing quality, schooling, income, teenage pregnancy, poverty density, access to prenatal care, and skin color as independent variables. The dependent variable was mapped to identify spatial patterns. The SINAN, SINASC, and IBGE databases were used for notifiable diseases, live births, and census data, respectively. A total of 6,274 cases of congenital syphilis were reported, which represents an incidence rate of 17.3 cases/1,000 live births. Cases were distributed in the central, northern peripheral, and western zones of the city, with a high proportion of cases in infants of black mothers with low schooling. There was also a high proportion of pregnant women with late diagnosis of syphilis and inadequate treatment. At the aggregate level, the most relevant variable for explaining the problem was the low proportion of pregnant women with at least 7 prenatal visits. The analysis allowed the identification of marginalized population segments and can help direct public health resources more effectively.