title: Ataxia-telangiectasia patients presenting with hyper-IgM syndrome.
abstract: Ataxia-telangiectasia (A-T) is characterised by progressive neurological abnormalities, oculocutaneous telangiectasias and immunodeficiency (decreased serum IgG subclass and/or IgA levels and lymphopenia). However, 10% of A-T patients present with decreased serum IgG and IgA with normal or raised IgM levels. As cerebellar ataxia and oculocutaneous telangiectasias are not present at very young age, these patients are often erroneously diagnosed as hyper IgM syndrome (HIGM). Eight patients with A-T, showing serum Ig levels suggestive of HIGM on first presentation, are described. All had decreased numbers of T lymphocytes, unusual in HIGM. The diagnosis A-T was confirmed by raised alpha-fetoprotein levels in all patients. To prevent mistaking A-T patients for HIGM it is proposed to add DNA repair disorders as a possible cause of HIGM.
authors.affiliation: Department of Paediatrics, Reinier de Graaf Gasthuis, Delft, The Netherlands. j.noordzij@rdgg.nl
authors.forename: J G
authors.initials: JG
authors.lastname: Noordzij
authors.forename: N M
authors.initials: NM
authors.lastname: Wulffraat
authors.forename: A
authors.initials: A
authors.lastname: Haraldsson
authors.forename: I
authors.initials: I
authors.lastname: Meyts
authors.forename: L J
authors.initials: LJ
authors.lastname: van't Veer
authors.forename: F B L
authors.initials: FB
authors.lastname: Hogervorst
authors.forename: A
authors.initials: A
authors.lastname: Warris
authors.forename: C M R
authors.initials: CM
authors.lastname: Weemaes
mesh_terms: D001260:Ataxia Telangiectasia / Q000276:immunology*; D002648:Child; D002675:Child, Preschool; D004260:DNA Repair; D005260:Female; D006801:Humans; D053306:Hyper-IgM Immunodeficiency Syndrome / Q000175:diagnosis* / Q000276:immunology; D007074:Immunoglobulin G / Q000032:analysis*; D007223:Infant; D018655:Lymphocyte Count; D008297:Male; D013601:T-Lymphocytes / Q000276:immunology
chemical_list: D007074:Immunoglobulin G