Epidemiology and Infection



Incidence of congenital toxoplasmosis estimated by neonatal screening: relevance of diagnostic confirmation in asymptomatic newborn infants


C. G. CARVALHEIRO a1, M. M. MUSSI-PINHATA a1c1, A. Y. YAMAMOTO a1, C. B. S. DE SOUZA a1 and L. M. Z. MACIEL a1
a1 Department of Pediatrics, Faculty of Medicine of Ribeirão Preto, University of São Paulo, São Paulo, Brasil

Article author query
carvalheiro cg   [PubMed][Google Scholar] 
mussi-pinhata mm   [PubMed][Google Scholar] 
yamamoto ay   [PubMed][Google Scholar] 
de souza cb   [PubMed][Google Scholar] 
maciel lm   [PubMed][Google Scholar] 

Abstract

Congenital toxoplasmosis is rarely identified by routine clinical examination. The aim of this study was to estimate the incidence of the disease in the region of Ribeirão Preto, south-eastern Brazil. A definitive diagnosis was made on the basis of the persistence of anti-Toxoplasma IgG antibodies beyond 1 year of age. Blood samples obtained from 15162 neonates and adsorbed onto filter paper were tested for anti-Toxoplasma IgM antibodies. Fifteen samples gave positive results. A definitive diagnosis was confirmed in five of the 13 infants (38·5%) who completed follow-up. These five infants presented with serum IgM and/or IgA antibodies, and clinical abnormalities. Disease incidence was estimated to be 3·3/10000 (95% CI 1·0–7·7), indicating the need for preventive measures. Neonatal screening is feasible, but screening tests with a better performance are required; positive screening results must be carefully confirmed.

(Accepted November 12 2004)


Correspondence:
c1 Av. Bandeirantes 3900, 14049-900, Ribeirão Preto, São Paulo, Brasil. Email: mmmpinha@fmrp.usp.br)


Metrics