Survey of 8,799 Cases Included in a Pilot Programme of Phase 2 to Expand Neonatal Screening in Porto Alegre, RS, Brazil

Ida Vanessa Doederlein Schwartz ^1,2 Livia Maria Ferreira Sobrinho ² Marina Acosta ² Luzivan Costa Reis ² Gabrielle Dineck Lopp ^1,3 Larissa Faquetti ^1,3 Antonio Lemos da Silva ^1,3 Vivian de Lima Spode Coutinho ^4,5 Roberto Giugliani ^1,2,3 Simone Martins de Castro ⁵

¹Hospital de Clínicas de Porto Alegre, Brazil
²Universidade Federal do Rio Grande do Sul, Brazil
³Casa Dos Raros, Brazil
⁴Hospital Materno Infantil Presidente Vargas, Brazil
⁵Serviço de Referência em Triagem Neonatal, Brazil

Background: Neonatal screening (NS) is a population health programme that aims to identify disorders and diseases in newborns (NB). This study describes the findings related to the 8,799 NB included in the pilot programme of phase 2 of NS expansion in Porto Alegre, RS, Brazil.

Methods: The project was approved by the coordinating ethics committee in October 2020, and collections started in June 2021 (duration: 62 weeks). Upon agreement of the family, an analysis by MS/MS (amino acids and acylcarnitines, 22 diseases) was performed on the newborns who had their NS collected at the municipality Basic Health Units (BHU). The results altered in the first collection were recalled and analysed in duplicate.

Results: Of the analysed samples (n: 8,799), the first collection was altered in 105 NB (1.19%). Of these, 24 (22.8%) remained with alterations and were called for a research consultation. The most frequent alterations in collections 1 and 2 were an increase in C4DC/C5-OH (without an increase in C3) and a decrease in C0. Of the patients summoned, 23 NB (95.8%) attended the consultation, 9 (39.1%) of which needed to be regulated, and 8 attended the consultation for regulation and remain under follow-up (glutaric aciduria 1-AG1: 1; heterozygous for def. CPS1: 1; VLCAD deficiency: 1; transitory alterations: 6). The median age at the first collection, recollection and research visit was 4.5, 18 and 34 days, respectively.

Discussion/Conclusion: This project shows the possibility and importance of conducting research for rare diseases. It demonstrated the existence of challenges in the usual NS process (such as difficulties related to active search), which must be urgently resolved by managers. The early diagnosis and treatment of AG1 predict normal neuropsychomotor development in this NB.