- Correspondence to Ana Méndez-Echevarría, Paediatric Department, La Paz Hospital, Paseo de la Castellana 261, 28046 Madrid, Spain;
- Accepted June 24, 2011
- First published May 4, 2011.
If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.