Use

This test is useful for preliminary screening of X-linked agammaglobulinemia, primarily in male patients under the age of 65 or female carriers of child-bearing age under 45. X-linked agammaglobulinemia (XLA) is a primary immunodeficiency caused by variants in the Bruton tyrosine kinase (BTK) gene. The test assesses protein expression levels and helps in determining whether further genetic analysis is warranted. It is an essential tool for the clinical evaluation of male patients with less than 1% B cells and suspected immunodeficiency. Absence of BTK protein expression provides a strong rationale for pursuing genetic sequencing.