Introduction: X-linked agammaglobulinemia (XLA) is due to mutations in the BTK gene. Objective: to describe epidemiological and clinical characteristics of pediatric patients with XLA.

Method: Observational, cross-sectional and descriptive study

Results:
Twelve patients were analyzed, all male, average age at onset of symptoms was: 23 months, a delay in diagnosis of: 43 months. 58% had a family history of PID. In ten patients (83%), infectious diseases were the first manifestation (5 patients pneumonia, 1 sepsis, 1 septic arthritis, 1 meningitis, 1 tuberculosis), one patient was diagnosed by screening (brother with XLA) and one patient debuted with juvenile rheumatoid arthritis and another with optic neuritis. Prior to diagnosis, eleven patients required hospitalization and intravenous antibiotics, three patients required intensive care. The following pathogens were identified: Cytomegalovirus, parvovirus, Neiseria spp, E. cloacae, S. maltophilia. P. aeruginosa, K. oxytoca. Five patients presented bronchiectasis (four cylindrical and one mixed). Seven patients receive intravenous gamma globulin and five subcutaneous. One has major depression. After diagnosis, two patients required hospitalization due to severe pneumonia because they had abandoned treatment. No patient presented alterations at the gastrointestinal level. One patient has severe lung damage, requiring supplemental oxygen, the rest of the patients have a normal life.
Conclusions: In patients with XLA, the delay and abandonment of treatment impoverishes the prognosis. In our pediatric population, pulmonary alteration (bronchiectasis) was found, but not in gastrointestinal tract.