TY - JOUR
T1 - Varicella Vaccination of Children With Leukemia Without Interruption of Maintenance Therapy
T2 - A Danish Experience
AU - Smedegaard, Lotte Møller
AU - Poulsen, Anja
AU - Kristensen, Ines Ackerl
AU - Rosthøj, Susanne
AU - Schmiegelow, Kjeld
AU - Nygaard, Ulrikka
PY - 2016/11/1
Y1 - 2016/11/1
N2 - Background: Varicella-zoster virus (VZV) can be fatal or cause severe complications in children with acute lymphoblastic leukemia (ALL). This analysis set out to investigate the morbidity and mortality of VZV vaccination without interruption of maintenance therapy in children with ALL.
Methods: Files of 73 seronegative children with ALL were examined for data regarding VZV vaccination and infection, and long-term seroconversion was measured. Criteria before VZV vaccination were (1) seronegative, (2) in complete remission, (3) age >= 1.0 year, (4) lymphocyte count >= 0.6 × 109/L at time of vaccination and (5) receiving maintenance therapy.
Results: Forty-five children were vaccinated. No child died or experienced serious adverse events due to VZV vaccination. Nine children developed late chickenpox despite vaccination. Long-term protection was found in 86% of children not receiving acyclovir and 78% of the entire population. Long-term seroconversion was found in 52% of the children. There were no severe cases of varicella infection. Acyclovir prophylaxis postvaccination was associated with an increased risk of late chickenpox [hazard ratio = 5.40 (1.43, 20.41), P = 0.01]. In contrast, a vaccine-induced rash reduced the risk of late chickenpox [hazard ratio = 0.08 (0.01, 0.66), P = 0.02]. No child had interruption of maintenance therapy at the time of vaccination, but 33% experienced discontinuation of therapy due to vaccine-induced rash. Dexamethasone was associated with an increased risk of vaccine-induced rash [hazard ratio = 2.9 (1.21, 6.90), P = 0.02].
Conclusions: This analysis indicates that VZV vaccination is feasible and justified in seronegative children with ALL, in countries where VZV vaccination is not part of the national vaccination program.
AB - Background: Varicella-zoster virus (VZV) can be fatal or cause severe complications in children with acute lymphoblastic leukemia (ALL). This analysis set out to investigate the morbidity and mortality of VZV vaccination without interruption of maintenance therapy in children with ALL.
Methods: Files of 73 seronegative children with ALL were examined for data regarding VZV vaccination and infection, and long-term seroconversion was measured. Criteria before VZV vaccination were (1) seronegative, (2) in complete remission, (3) age >= 1.0 year, (4) lymphocyte count >= 0.6 × 109/L at time of vaccination and (5) receiving maintenance therapy.
Results: Forty-five children were vaccinated. No child died or experienced serious adverse events due to VZV vaccination. Nine children developed late chickenpox despite vaccination. Long-term protection was found in 86% of children not receiving acyclovir and 78% of the entire population. Long-term seroconversion was found in 52% of the children. There were no severe cases of varicella infection. Acyclovir prophylaxis postvaccination was associated with an increased risk of late chickenpox [hazard ratio = 5.40 (1.43, 20.41), P = 0.01]. In contrast, a vaccine-induced rash reduced the risk of late chickenpox [hazard ratio = 0.08 (0.01, 0.66), P = 0.02]. No child had interruption of maintenance therapy at the time of vaccination, but 33% experienced discontinuation of therapy due to vaccine-induced rash. Dexamethasone was associated with an increased risk of vaccine-induced rash [hazard ratio = 2.9 (1.21, 6.90), P = 0.02].
Conclusions: This analysis indicates that VZV vaccination is feasible and justified in seronegative children with ALL, in countries where VZV vaccination is not part of the national vaccination program.
KW - varicella zoster virus
KW - vaccination
KW - pediatrics
KW - acute lymphoblastic leukemia
KW - childhood leukemia
U2 - 10.1097/INF.0000000000001279
DO - 10.1097/INF.0000000000001279
M3 - Journal article
SN - 0891-3668
VL - 35
SP - e348-e352
JO - The Pediatric Infectious Disease Journal
JF - The Pediatric Infectious Disease Journal
IS - 11
ER -