Bibiana Mello de Oliveira, Monique Sartori Broch, Carolina Peçaibes de Oliveira, Angélica Piovesana, Claudia Fernandes Lorea, Mariana Lima Scortegagna, Gabriella Zanin Fighera, Isadora Viegas, Laíse Pauletti Barp, Mateus Alonso, Alberto Vergara, Ana Maria Martins, Anete Sevciovic Grumach, Angelina Xavier Acosta, Bethania de Freitas Rodrigues Ribeiro, Camila Ferreira Ramos, Carlos Henrique Paiva Grangeiro, Chong Ae Kim, Debora Gusmão Melo, Débora Michelatto, Denise Christofolini, Ellaine Doris Fernandes Carvalho, Erlane Marques Ribeiro, Faradiba Sarquis Serpa, Flavia Resedá Brandão, Isabella Lopes Monlleó, Joyceane Alves Oliveira, Juan Clinton Llerena, Karina Carvalho Donis, Liane de Rosso Giuliani, Louise Lapagesse de Camargo Pinto, Luiz Carlos Santana da Silva, Marcela Câmara Machado Costa, Marcial Francis Galera, Marcia Maria Costa Giacon Giusti, Mara Lucia Schmitz Ferreira Santos, Maria Denise Fernandes Carvalho de Andrade, Maria Teresinha De Oliveira Cardoso, Milena Coelho Fernandes Caldato, Natalya Gonçalves Pereira, Ney Boa Sorte, Paula Frassinetti Vasconcelos de Medeiros, Paulo Ricardo Gazzola Zen, Raquel Tavares Boy da Silva, Rayana Elias Maia, Sandra Obikawa Kyosen, Solange Valle, Tatiana Amorim, Thaís Bomfim Teixeira, Vania Mesquita Gadelha Prazeres, Victor Evangelista de Faria Ferraz, Ida Vanessa Doederlein Schwartz, Domingos Alves, Têmis Maria Félix, Raras Network Group
The diagnostic odyssey for rare diseases in Brazil remains prolonged and heterogeneous, reflecting structural disparities, healthcare fragmentation, and diagnostic complexity. These findings suggest that delays are not driven solely by limited access to advanced diagnostics, but also by barriers in early recognition, referral pathways, and care coordination, underscoring the need for integrated strategies across the health system.
BACKGROUND: The diagnostic odyssey of individuals with rare diseases is prolonged and associated with clinical, emotional, and financial burden. In Brazil, data on diagnostic delays and their determinants remain scarce.
OBJECTIVE: This study aims to characterize the diagnostic odyssey of individuals with rare diseases using data from the Brazilian Rare Diseases Network (RARAS).
METHODS: This descriptive cross-sectional study analyzed ambispective data collected from 2018-2025 across RARAS centers nationwide. Diagnostic odyssey was defined as the time between symptom onset and definitive diagnosis. Prenatal and newborn screening diagnoses were excluded. Sociodemographic, clinical and etiological data were collected through a standardized REDCap-based instrument.
RESULTS: Among 18,625 unique participants, 12,048 had confirmed diagnoses and 5,984 met criteria for diagnostic odyssey analysis. The mean diagnostic interval was 6.21 years (± 8.41; median 2.94, IQR 0.80-8.13), indicating substantial heterogeneity. Longer delays were observed in individuals with symptom onset during adolescence. Patients referred during hospital admission experienced shorter diagnostic intervals. Regional differences were significant (p <0.001), with longer intervals in the Southeast region. Mean time to diagnosis ranged from 2.01 (± 2.89) years (achondroplasia) to 16.40 (± 12.59) years (hereditary angioedema). Patients consulted a mean of 5.32 (± 9.63) physicians and accessed 3.15 (± 4.96) healthcare services before diagnosis. Diagnostic intervals varied by race/ethnicity and etiological category, with longer delays among those with molecular diagnoses, while no association was observed with socioeconomic class.
CONCLUSION: The diagnostic odyssey for rare diseases in Brazil remains prolonged and heterogeneous, reflecting structural disparities, healthcare fragmentation, and diagnostic complexity. These findings suggest that delays are not driven solely by limited access to advanced diagnostics, but also by barriers in early recognition, referral pathways, and care coordination, underscoring the need for integrated strategies across the health system.