Temporary blast reduction after immunoglobulin administration for congenital cytomegalovirus infection masking infant leukemia with cryptic MLL rearrangement.
Differentiation between reactive bone marrow suppression due to viral infection and early stages of leukemia can be difficult particularly in young infants. We report on a 2-month-old girl presenting with pancytopenia and positive markers for congenital cytomegalovirus (CMV) infection. Definitive diagnosis of coexisting pro-B cell infant leukemia with cryptic MLL rearrangement was delayed by the transient regeneration of normal hematopoiesis and reduction of abnormal blastoid cells in the bone marrow following immunoglobulin administration. Molecular diagnosis could only be established using interphase fluorescence in situ hybridization (FISH) analysis which may be considered as a valuable additional diagnostic tool in similar cases.
Metzler
Markus
M
Department of Pediatrics, University of Erlangen-Nuremberg, Erlangen, Germany. markusmetzler@email.de
Bruch
Jochen
J
Stachel
Daniel
D
Langer
Thorsten
T
Borkhardt
Arndt
A
Harbott
Jochen
J
Rascher
Wolfgang
W
Holter
Wolfgang
W
D001752:Blast Crisis / Q000628:therapy*; D001853:Bone Marrow / Q000473:pathology; D003587:Cytomegalovirus / Q000302:isolation & purification; D003586:Cytomegalovirus Infections / Q000151:congenital / Q000628:therapy*; D005260:Female; D005434:Flow Cytometry; D015321:Gene Rearrangement; D011495:Histone-Lysine N-Methyltransferase; D006801:Humans; D016756:Immunoglobulins, Intravenous / Q000008:administration & dosage*; D017404:In Situ Hybridization, Fluorescence; D007223:Infant; D015448:Leukemia, B-Cell / Q000175:diagnosis* / Q000235:genetics; D051788:Myeloid-Lymphoid Leukemia Protein / Q000235:genetics*; D010198:Pancytopenia; D015452:Precursor B-Cell Lymphoblastic Leukemia-Lymphoma / Q000175:diagnosis* / Q000235:genetics
D016756:Immunoglobulins, Intravenous; C497422:KMT2A protein, human; D051788:Myeloid-Lymphoid Leukemia Protein; D011495:Histone-Lysine N-Methyltransferase