X-linked agammaglobulinemia with bronchiectasis and infection： a case report

X-linked agammaglobulinemia (XLA) is a rare disease characterized by severe hypogammaglobulinemia, antibody deficiency, and recurrent infections. This study reports a case of X-linked agammaglobulinemia combined with bronchiectasis and infection. The patient was a 45-year-old male with a disease course of more than 40 years, mainly presenting with recurrent infections such as pneumonia, sinusitis, and otitis media. After the patient was admitted due to bronchiectasis with infection this time, laboratory tests showed that the levels of IgM, IgA, and IgG were 0.24 g/L, 0.90 g/L, and 4.33 g/L, respectively, all significantly decreased, and the peripheral blood CD19+B lymphocyte count was 0.1%. Genetic testing results showed that the patient had a c.1095C>A (p.Asn365Lys) mutation in the Bruton's tyrosine kinase (Btk) gene. This case suggests that male patients with a history of recurrent infections and imaging evidence of bronchiectasis should further understand their family history, improve humoral and cellular immune testing, and perform genetic testing in a timely manner, which is beneficial for the early diagnosis and treatment of XLA.