Leukocyte suppression is associated with improved clinical outcomes in children's status after orthotopic heart transplantation.
BACKGROUND
Leukocyte suppression is a sequela of immunosuppressive therapy after orthotopic heart transplantation and may result in discontinuation of anti-proliferative agents. Clinical outcomes in this patient population have not been well delineated.


METHODS
This study was a retrospective review of children who underwent orthotopic heart transplantation at our institution from 1986 to 2003. Leukocyte suppression was defined as a white blood cell count <5,000, prompting the withdrawal of anti-proliferative agents. The population was divided into 2 groups, leukosuppressed (LS) and non-leukosuppressed (NLS), and their clinical outcomes were compared.


RESULTS
The study included 109 patients, of which 44 (40%) became leukosuppressed. The 2 groups were similar regarding demographic data and initial management. The LS Group had a significantly decreased incidence of rejection, being 7 times less likely to have recurrent rejection (p = 0.001). The median time to rejection was 0.8 +/- 0.6 years for the NLS Group, whereas the median time to rejection was not yet reached at 17 years for the LS Group. The LS Group also tended toward a decreased incidence of retransplantation or death (p = 0.06). The organ "half-life" in the NLS Group was 7.5 years vs 12.5 years in the LS Group. There was no difference between the 2 groups in regards to other adverse effects of immunosuppression.


CONCLUSIONS
Children who have undergone orthotopic heart transplantation and subsequently become leukosuppressed have a lower incidence of rejection and a tendency toward less organ loss than children who do not become leukosuppressed, without having an increased incidence of adverse side effects.
Kim
Jeffrey J
JJ
Section of Pediatric Cardiology, Department of Pediatrics, Baylor College of Medicine, Texas Children's Hospital, Houston, Texas 77030, USA. jjkim@texaschildrenshospital.org
Dreyer
William J
WJ
O'Brian Smith
E
E
Price
Jack F
JF
Clunie
Sarah
S
Dimas
V Vasiliki
VV
Jefferies
John L
JL
Rosenblatt
Howard
H
Radovancevic
Branislav
B
Towbin
Jeffrey A
JA
Denfield
Susan W
SW
D000293:Adolescent; D049109:Cell Proliferation / Q000187:drug effects; D002648:Child; D002675:Child, Preschool; D005260:Female; D006084:Graft Rejection / Q000209:etiology / Q000503:physiopathology / Q000517:prevention & control; D016027:Heart Transplantation / Q000276:immunology* / Q000379:methods / Q000473:pathology; D006801:Humans; D007165:Immunosuppression Therapy / Q000009:adverse effects; D007166:Immunosuppressive Agents / Q000009:adverse effects / Q000494:pharmacology* / Q000627:therapeutic use; D007223:Infant; D007962:Leukocytes / Q000187:drug effects* / Q000473:pathology* / Q000502:physiology; D007970:Leukopenia / Q000139:chemically induced; D008297:Male; D015999:Multivariate Analysis; D011183:Postoperative Complications / Q000276:immunology / Q000473:pathology; D012189:Retrospective Studies; D012307:Risk Factors; D016896:Treatment Outcome
D007166:Immunosuppressive Agents