1. Immunology Department, Hospital Infantil de Especialidades de Chihuahua, Chihuahua, Mexico
2. Hospital IMSS de Gineco Obstetricia No. 15, Chihuahua, Chihuahua, Mexico
3. Neonatology Department, Hospital IMSS de Gineco Obstetricia No. 15, Chihuahua, Chihuahua, Mexico
4. Cardiology Department, Hospital IMSS Morelos Chihuahua, Chihuahua, Mexico
5. Cardiology Department, Hospital Angeles Chihuahua, Chihuahua, México
6. Oncology Department, Hospital Infantil de Especialidades de Chihuahua, Chihuahua, Mexico
7. Immunology Department, Instituto Nacional de Pediatría, Mexico city, Mexico