1. Unit of Pediatric Nephrology, Department of Pediatrics, Cayetano Heredia National Hospital, Avenida Honorio Delgado 265, SMP, Lima 31, Peru
2. Cayetano Heredia University, Avenida Honorio Delgado 430, SMP, Lima 31, Peru
3. Unit of Pediatric Nephrology, Sergio Bernales National Hospital, Avenida Tupac Amaru 8000, Comas, Lima 7, Peru