title: [Jacobsen's syndrome, thrombopenia and humoral immunodeficiency].
abstract: BACKGROUND
  Clinical features of Jacobsen syndrome include facial dysmorphism, congenital heart defects, digit anomalies and mild to moderate psychomotor retardation. Thrombocytopenia or pancytopenia is observed in one half of patients.
  
  
  METHODS
  Two unrelated children, a 6-month- and a 12-year-old, presented with a moderate thrombocytopenia associated with the clinical features of Jacobsen syndrome. Bone marrow aspirates showed, in both patients, normal cellularity with an increased number of micromegacaryocytes. Chromosome analysis showed a partial deletion of the long arm of chromosome 11. The 12-year-old patient had a history of upper respiratory airways infections with immune humoral deficiency (decreased level of IgA and IgM) which, to our knowledge, has never been reported.
  
  
  CONCLUSIONS
  Jacobsen syndrome is a cause of inherited thrombocytopenia in children. Humoral immune functions must be explored in patients with a history of repeated infections.
authors.affiliation: Service de pédiatrie, hôpital de l'Archet, Nice, France.
authors.forename: N
authors.initials: N
authors.lastname: Sirvent
authors.forename: F
authors.initials: F
authors.lastname: Monpoux
authors.forename: F
authors.initials: F
authors.lastname: Pedeutour
authors.forename: M
authors.initials: M
authors.lastname: Fraye
authors.forename: P
authors.initials: P
authors.lastname: Philip
authors.forename: M
authors.initials: M
authors.lastname: Ticchioni
authors.forename: C
authors.initials: C
authors.lastname: Turc-Carel
authors.forename: R
authors.initials: R
authors.lastname: Mariani
mesh_terms: D002648:Child; D002872:Chromosome Deletion; D002880:Chromosomes, Human, Pair 11; D004406:Dysgammaglobulinemia / Q000150:complications*; D005145:Face / Q000002:abnormalities*; D005260:Female; D005385:Fingers / Q000002:abnormalities*; D006330:Heart Defects, Congenital / Q000150:complications*; D006801:Humans; D017098:IgA Deficiency / Q000150:complications*; D007075:Immunoglobulin M / Q000172:deficiency*; D007223:Infant; D008297:Male; D011596:Psychomotor Disorders / Q000150:complications*; D013577:Syndrome; D013921:Thrombocytopenia / Q000150:complications*
chemical_list: D007075:Immunoglobulin M