It has been observed that some children with immune-mediated
thrombocytopenia (
ITP) who are treated with
intravenous immunoglobulin (
IVIG) experience a decline in their absolute neutrophil count (ANC). The aim of this study was to investigate the incidence of
neutropenia following
IVIG therapy in a large cohort of children with
ITP. This retrospective comparative cohort study determined the incidence of
neutropenia in 104 patients (110 treatment courses) admitted for
ITP to the Children's Hospital of Philadelphia from January 2000 to October 2003. Post-treatment ANCs were compared between patients who received
IVIG and patients who received
anti-D immunoglobulin. The incidence of
neutropenia in each group was analyzed using the Fisher exact test. Pretreatment ANCs were not significantly different between the two treatment groups (P = 0.72).
Neutropenia (ANC < 1,500/microL), developed during 18 of 64 (28%) treatment courses with
IVIG, compared with 0 of 46 (0%) treatment courses with
anti-D immunoglobulin (P < 0.001). This study suggests that
IVIG may cause
neutropenia commonly in children with
ITP. While this is likely to be a transient condition, its recognition may affect clinical decisions such as the need for a bone marrow examination.