title: X-linked agammaglobulinemia diagnosed in adulthood: a case report.
abstract: X-linked agammaglobulinemia (XLA) is a humoral immunodeficiency caused by mutations in Bruton's tyrosine kinase (BTK). Patients typically become symptomatic during infancy or early childhood and develop recurrent bacterial infections. We report a Japanese case of XLA diagnosed in a patient who was 27 years of age and who had no history of severe infection. The patient's serum immunoglobulin (Ig) G, IgA, and IgM levels were 132,7, and 17 mg/dL, respectively. The percentage of positive cells for CD19 and CD20 was 0.03% and 0.02%, respectively. The patient's brother and sister had no abnormalities. Flow cytometric analysis showed a partially reduced expression of BTK protein in the patient's peripheral monocytes. Sequencing of the BTK. gene revealed a missense mutation (230C>T,T33I). Given this data, this patient was diagnosed as having rare, late onset XLA with a missense mutation in the BTK gene.
authors.affiliation: Department of Medicine and Clinical Science, Graduate School of Medicine, Gunma University, Maebashi, Japan.
authors.forename: Takeki
authors.initials: T
authors.lastname: Mitsui
authors.forename: Norifumi
authors.initials: N
authors.lastname: Tsukamoto
authors.forename: Hirokazu
authors.initials: H
authors.lastname: Kanegane
authors.forename: Kazunaga
authors.initials: K
authors.lastname: Agematsu
authors.forename: Tomomi
authors.initials: T
authors.lastname: Sekigami
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Irisawa
authors.forename: Takayuki
authors.initials: T
authors.lastname: Saitoh
authors.forename: Hideki
authors.initials: H
authors.lastname: Uchiumi
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Handa
authors.forename: Takafumi
authors.initials: T
authors.lastname: Matsushima
authors.forename: Masamitsu
authors.initials: M
authors.lastname: Karasawa
authors.forename: Hirokazu
authors.initials: H
authors.lastname: Murakami
authors.forename: Toshio
authors.initials: T
authors.lastname: Miyawaki
authors.forename: Yoshihisa
authors.initials: Y
authors.lastname: Nojima
mesh_terms: D000328:Adult; D000077329:Agammaglobulinaemia Tyrosine Kinase; D000361:Agammaglobulinemia / Q000097:blood / Q000235:genetics* / Q000382:microbiology; D044466:Asian People; D001424:Bacterial Infections / Q000097:blood / Q000235:genetics; D015971:Gene Expression Regulation, Enzymologic / Q000235:genetics; D040181:Genetic Diseases, X-Linked / Q000097:blood / Q000235:genetics* / Q000382:microbiology; D006801:Humans; D007136:Immunoglobulins / Q000097:blood; D007564:Japan; D007958:Leukocyte Count; D008297:Male; D020125:Mutation, Missense; D011505:Protein-Tyrosine Kinases / Q000096:biosynthesis / Q000235:genetics*
chemical_list: D007136:Immunoglobulins; D011505:Protein-Tyrosine Kinases; D000077329:Agammaglobulinaemia Tyrosine Kinase; C000625949:BTK protein, human