Manuela Olaya Hernández, Jacobo Triviño Arias, Oriana Arias Valderrama, Vanessa Cabrera Guarín, Jaime Alberto Patiño, Harry Mauricio Pachajoa, Diego Medina Valencia, Alexis Antonio Franco, Lina M Castaño Jaramillo, Natalia Vélez Tirado, Andrés Felipe Zea-Vera, María Claudia Ortega-López, Carlos Olmos-Olmos, Yaicith Arévalo-Montenegro, Laura Rincón-Arenas, José Luis Franco, Julio Cesar Orrego, Estefanía Vásquez, Catalina Obando-Gil, Isabel Moribe, Maria Lucía Valderrama, Catalina Gómez-Parada, Marta Álvarez, Andrés Felipe Arias, Paola Marsela Pérez, Oscar Correa Jiménez
Thirty-eight males were analyzed, with a median age at diagnosis of 16 months (IQR 7.2-21.8). Genetic testing was available for 84.2% (n = 32), identifying 15 distinct variants, 53% of which were novel. Sinopulmonary infections were the primary manifestation (92.1%), notably pneumonia (42.1%) and otitis media (39.5%). Median baseline IgG levels were 187 mg/dL. Bronchiectasis was documented in 34.2% of cases. The eight-year survival rate was 71.1%.
INTRODUCTION: X-linked Agammaglobulinemia (XLA) is an inborn error of immunity (IEI) caused by mutations in the BTK gene, resulting in the absence of mature B-cells and altered serum immunoglobulin levels. In Colombia, unified epidemiological and genetic data are lacking. This study aims to characterize XLA patients in the country demographically, phenotypically, and genotypically.
METHODS: A multicenter, observational, cross-sectional study based on clinical records. Thirty-eight patients with B-cell counts <2% and hypogammaglobulinemia were included. Clinical, immunological, and genetic variables and outcomes were analyzed using descriptive statistics in R-Studio.
RESULTS: Thirty-eight males were analyzed, with a median age at diagnosis of 16 months (IQR 7.2-21.8). Genetic testing was available for 84.2% (n = 32), identifying 15 distinct variants, 53% of which were novel. Sinopulmonary infections were the primary manifestation (92.1%), notably pneumonia (42.1%) and otitis media (39.5%). Median baseline IgG levels were 187 mg/dL. Bronchiectasis was documented in 34.2% of cases. The eight-year survival rate was 71.1%.
DISCUSSION: The Colombian cohort shows a relatively early diagnosis but a high burden of structural sequelae (bronchiectasis), suggesting a need to optimize immunoglobulin replacement therapy. The high proportion of novel genetic variants underscores the importance of regional studies. This study represents the most robust characterization of XLA in Colombia, providing key data to improve clinical suspicion and prognosis.