Atypical X-linked agammaglobulinemia diagnosed in adulthood with arthritis caused by a hypomorphic BTK splice-site variant: a case report and literature review
X-linked agammaglobulinemia (XLA) is an inborn error of immunity (IEI) caused by loss-of-function variants in the Bruton tyrosine kinase (BTK) gene, classically presenting in early childhood with recurrent bacterial infections. Here, we report an atypi…