title: Large granular lymphocyte proliferation and revertant mosaicism: two rare events in a Wiskott-Aldrich syndrome patient.
abstract: We report on a 6 year old patient with an unusual clinical presentation of WAS and oligoclonal proliferation of TCR+ large granular lymphocytes (LGL). Flow cytometry demonstrated two distinct populations of lymphocytes with strongly decreased (WASP-) or normal expression levels of WASP (WASP+), respectively. Molecular analysis confirmed a splice site mutation in intron 2 of the WASP gene in the WASP- cells but not in WASP+ cells. LGL cells were WASP+, suggesting that two independent rare events, somatic revertant mosaicism and LGL expansion, have occurred in a child with WAS. Our report points to diagnostic difficulties in the presence of partial WASP reversions and LGL.
authors.affiliation: Department of Pediatric Hematology/Oncology, Medical School Hannover, D-30625 Hannover, Germany.
authors.forename: Kaan
authors.initials: K
authors.lastname: Boztug
authors.forename: Ulrich
authors.initials: U
authors.lastname: Baumann
authors.forename: Matthias
authors.initials: M
authors.lastname: Ballmaier
authors.forename: David
authors.initials: D
authors.lastname: Webster
authors.forename: Inga
authors.initials: I
authors.lastname: Sandrock
authors.forename: Roland
authors.initials: R
authors.lastname: Jacobs
authors.forename: Thomas
authors.initials: T
authors.lastname: Lion
authors.forename: Sandra
authors.initials: S
authors.lastname: Preuner
authors.forename: Manuela
authors.initials: M
authors.lastname: Germeshausen
authors.forename: Gesine
authors.initials: G
authors.lastname: Hansen
authors.forename: Karl
authors.initials: K
authors.lastname: Welte
authors.forename: Christoph
authors.initials: C
authors.lastname: Klein
mesh_terms: D002469:Cell Separation; D002648:Child; D003937:Diagnosis, Differential; D005434:Flow Cytometry; D006192:Haemophilus Infections / Q000150:complications; D006801:Humans; D007438:Introns / Q000235:genetics; D008232:Lymphoproliferative Disorders / Q000209:etiology* / Q000235:genetics / Q000473:pathology; D008297:Male; D009030:Mosaicism; D009154:Mutation; D016553:Purpura, Thrombocytopenic, Idiopathic / Q000175:diagnosis; D022821:RNA Splice Sites / Q000235:genetics*; D016692:Receptors, Antigen, T-Cell, gamma-delta / Q000032:analysis; D012008:Recurrence; D016176:T-Lymphocyte Subsets / Q000737:chemistry / Q000473:pathology*; D014923:Wiskott-Aldrich Syndrome / Q000097:blood / Q000150:complications* / Q000175:diagnosis / Q000235:genetics; D051316:Wiskott-Aldrich Syndrome Protein / Q000032:analysis / Q000172:deficiency / Q000235:genetics
chemical_list: D022821:RNA Splice Sites; D016692:Receptors, Antigen, T-Cell, gamma-delta; C495767:WAS protein, human; D051316:Wiskott-Aldrich Syndrome Protein