title: Severe neutropenia in Japanese patients with x-linked agammaglobulinemia.
abstract: X-linked agammaglobulinemia (XLA) is clinically characterized by recurrent bacterial infections during early infancy. Although it is not a phagocytic disorder, XLA is sometimes associated with neutropenia. We conducted a nation-wide survey to determine the frequency of neutropenia among Japanese XLA patients. Responses were received from 87 (86%) of 101 patients in which BTK mutations were previously identified, and of these, 16 (18%) had neutropenia. All episodes of neutropenia occurred before initiation of intravenous immunoglobulin (IVIG) replacement therapy. Two XLA patients died of multiple organ failure caused by severe neutropenia and Pseudomonas sepsis before initiation of IVIG replacement therapy. These results suggest that, in some cases, severe bacterial infections in XLA patients might be caused not only by antibody deficiencies but also by neutropenia.
authors.affiliation: Department of Pediatrics, Faculty of Medicine, Toyama Medical and Pharmaceutical University, Japan. kanegane@ms.toyama-mpu.ac.jp
authors.forename: Hirokazu
authors.initials: H
authors.lastname: Kanegane
authors.forename: Hiromichi
authors.initials: H
authors.lastname: Taneichi
authors.forename: Keiko
authors.initials: K
authors.lastname: Nomura
authors.forename: Takeshi
authors.initials: T
authors.lastname: Futatani
authors.forename: Toshio
authors.initials: T
authors.lastname: Miyawaki
mesh_terms: D000077329:Agammaglobulinaemia Tyrosine Kinase; D000361:Agammaglobulinemia / Q000097:blood / Q000235:genetics* / Q000628:therapy; D002648:Child; D002675:Child, Preschool; D040181:Genetic Diseases, X-Linked / Q000097:blood / Q000235:genetics* / Q000628:therapy; D006801:Humans; D016756:Immunoglobulins, Intravenous / Q000627:therapeutic use; D015994:Incidence; D007223:Infant; D007564:Japan / Q000453:epidemiology; D007958:Leukocyte Count; D009154:Mutation; D009503:Neutropenia / Q000453:epidemiology / Q000209:etiology* / Q000628:therapy; D011379:Prognosis; D011505:Protein-Tyrosine Kinases / Q000235:genetics; D011795:Surveys and Questionnaires
chemical_list: D016756:Immunoglobulins, Intravenous; D011505:Protein-Tyrosine Kinases; D000077329:Agammaglobulinaemia Tyrosine Kinase; C000625949:BTK protein, human