The aim of the study was the evaluation of safety and efficacy of vaccination in children after stem cell transplantation.
Patients and methods: 21 patients, 1.4-22 (average 7.8) years old, 13 boys and 8 girls after autologous (11-52%) and allogeneic (10-48%) transplantation were included in the vaccination protocol. Indications for transplantation were: neoplastic disease--16, immunodeficiencies--3 and aplastic anaemia 2 cases. Time between transplantation and beginning of vaccination protocol was 0.8-4 (average 1.5) years. Vaccination protocol was constructed on the basis of the European Group for Blood and Marrow Transplantation indications. We have evaluated: (1) quality of recipient immune reconstitution and protection against common pathogens (2) immunogenicity of revaccination schedule; (3) safety of the vaccination programme.
Results: With the exception of one patient presenting with repeated fever, lymph node enlargement, muscle and joint pain, no important side effects were observed. Meningococcial meningitis developed in one patient who refused vaccination. The mean concentrations of antibodies in the plasma before and after vaccination were as follows: anti-diphteria (54; 2285), anti-tetanus (136; 3149) and anti-hepatitis B virus (anti-HBs: 24; 474) IU/ml.
Conclusions: (1) Vaccination in patients after transplantation is efficient and well tolerated. (2) Significant increase of antibody level was detected. (3) Any delay in beginning the vaccination can result in life threatening complications.