Serologic study on parvovirus b19 infection in childhood acute lymphoblastic leukemia during chemotherapy: clinical and hematologic implications.
OBJECTIVE
To present a first descriptive serologic study on the clinical and hematologic implications of parvovirus B19 (B19) infection in children with acute lymphoblastic leukemia from the time of initial admission until discontinuation of chemotherapy.


METHODS
Seventy-five patients were studied by polymerase chain reaction, enzyme-linked immunosorbent assay, sequencing, and immunodiffusion.


RESULTS
During the period of observation, 8% (4/48) of B19-seronegative patients seroconverted and infection triggered profound anemia and thrombocytopenia. B19-specific IgG disappeared in 26% (8/31) of B19-seropositive patients, and these patients were significantly younger and the B19 IgG titers were lower on admission compared with patients who continuously displayed B19 IgG. B19 DNA was detected in the seroconverting patients, and this helped in determining the time of infection, which coincided with a B19 epidemic in 75% (3/4) of patients. Patients typically presented with fever and myalgia; a rash, indicative of B19 infection, was observed in only one patient.


CONCLUSIONS
B19 infection was able to mimic a leukemic relapse or therapy-induced cytopenia and led to hospital admission, frequent blood sampling, renewed bone marrow aspirates, multiple transfusions of red blood cells or platelets, and cessation of maintenance chemotherapy for up to 3 weeks. The peculiar disappearance of B19-specific IgG, which could not be ascribed to a generalized low level of serum immunoglobulins, has not been previously reported. The results indicate that B19 should be assayed at diagnosis of leukemia to avoid subsequent diagnostic uncertainty, and during treatment in B19-seronegative patients exhibiting unexplained cytopenia.
Heegaard
Erik D
ED
Department of Clinical Microbiology, University State Hospital, Rigshospitalet, Copenhagen, Denmark. e.heegaard@immi.ku.dk
Schmiegelow
Kjeld
K
D000293:Adolescent; D000914:Antibodies, Viral / Q000097:blood*; D002648:Child; D002675:Child, Preschool; D004279:DNA, Viral / Q000097:blood*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D005779:Immunodiffusion; D007074:Immunoglobulin G / Q000097:blood*; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D010322:Parvoviridae Infections / Q000175:diagnosis / Q000821:virology*; D016732:Parvovirus B19, Human / Q000235:genetics / Q000276:immunology / Q000302:isolation & purification*; D016133:Polymerase Chain Reaction; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000175:diagnosis / Q000821:virology*; D015995:Prevalence; D012189:Retrospective Studies
D000914:Antibodies, Viral; D004279:DNA, Viral; D007074:Immunoglobulin G