TABLE E4.

Intravenous gamma globulin after transplantation

IVIG administration
All centers administer gamma globulin supplementation in the early posttransplantation period to achieve a trough IgG level of approximately 500 to 700 mg/dL, the higher level for patients with pre-existing or ongoing pulmonary complications, such as bronchiectasis.
A variety of criteria are used to discontinue gamma globulin. Some centers taper or discontinue the gamma globulin after 6-12 mo. Some wait until the serum IgM level has reached a near-normal concentration. Others immunize the patient to an antigen for which there is no antibody in the therapeutic gamma globulin preparations. There is general agreement that it is important to immunize the patient after the gamma globulin therapy has been discontinued and verify antigen-specific antibody levels. If the patient is unable to make antigen-specific antibody after immunization, gamma globulin therapy should be restarted.
Patients lacking donor B cells continue to receive gamma globulin unless there is evidence of host antibody responses, such as increasing trough serum IgG levels while on stable gamma globulin doses and antigen-specific antibody titers to immunizations.
Gamma globulin replacement should be continued in patients undergoing immunosuppressive therapy for GVHD or autoimmune conditions.
The following should be noted: The majority of patients lacking donor B cells will require IVIG for life. The presence of normal serum IgM or IgA levels, the presence of isohemagglutinins, or both DO NOT always indicate an ability to make antigen-specific IgG.
When to stop IVIG
For patients off immunosuppressive therapy, without GVHD, immunoglobulin replacement can be stopped when the trough serum IgG level is >600 mg/dL on stable immunoglobulin replacement doses. Some centers prefer to continue IVIG until there is evidence of donor B cells, preferably immunoglobulin-switched B cells. Consider increasing the interval between IVIG doses by 2 weeks. If the serum IgG level remains >600 mg/dL, the replacement can be discontinued. Monitoring IgG levels and specific antibody responses after stopping IVIG is essential because reinstitution of IVIG might be needed for adequate protection.
Vaccine administration
After discontinuation of the immunoglobulin therapy, administration of vaccines can begin on a schedule similar to that given to normal infants, with the exception of live vaccines. Prevaccine and postvaccine titers must be measured to determine responses. Vaccinations with toxoid, such as DTaP, or protein-conjugated polysaccharide vaccines (HIB and 7-valent pneumococcal conjugate vaccine) can be initiated immediately after criteria for discontinuation of IVIG have been met. In contrast, immunization with live vaccines (chicken pox, MMR, and rotavirus) should not be considered until at least 2 y after HCT AND should not be initiated until at least 12-15 mo after cessation of IVIG. In addition, for live vaccines, the patient should be off of all immunosuppressive therapy without evidence of GVHD. Some groups also recommend evidence of response to at least 2 posttransplantation killed vaccines before administering any live vaccines.
Example of potential revaccination schedule	DTaP ×3, IPV ×3, HIB ×3, Prevnar ×3, hepatitis B ×3 Killed influenza vaccine, yearly starting 6 mo after HCT Booster: DTaP, HIB, Prevnar, IPV 12 mo after primary series completed

DTaP, Diphtheria, tetanus, and pertussis vaccine; HIB, Haemophilus influenzae type b vaccine; IPV, inactivated (Salk) polio vaccine; IVIG, intravenous immunoglobulin; MMR, measles-mumps-rubella.