Large granular lymphocyte proliferation and revertant mosaicism: two rare events in a Wiskott-Aldrich syndrome patient.
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.
Boztug
Kaan
K
Department of Pediatric Hematology/Oncology, Medical School Hannover, D-30625 Hannover, Germany.
Baumann
Ulrich
U
Ballmaier
Matthias
M
Webster
David
D
Sandrock
Inga
I
Jacobs
Roland
R
Lion
Thomas
T
Preuner
Sandra
S
Germeshausen
Manuela
M
Hansen
Gesine
G
Welte
Karl
K
Klein
Christoph
C
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
D022821:RNA Splice Sites; D016692:Receptors, Antigen, T-Cell, gamma-delta; C495767:WAS protein, human; D051316:Wiskott-Aldrich Syndrome Protein