IVIg to Treat BK Viremia in Kidney Transplant Recipients

Inclusion Criteria: * Voluntary written informed consent before performance of any study-related procedure not part of normal medical care, with the understanding that consent may be withdrawn by the subject at any time without prejudice to future medical care. * Female subject is either postmenopausal for at least 1 year before the screening visit, is surgically sterilized or if they are of childbearing potential, agree to practice effective methods of contraception from the time of signing the informed consent form through 30 days after the last dose of intravenous immune globulin, or agree to completely abstain from heterosexual intercourse. * Kidney transplant recipients (living and deceased donors) with new onset BK viremia (defined as BKV plasma DNA load \>1000 copies/mL by real-time PCR within 2 weeks of enrollment). For values \>5000 copies/mL repeat testing is not required. For values ≤5000 copies/mL repeat testing should be performed to confirm viremia before enrollment. * Immunosuppression therapy at enrollment with tacrolimus, MPA, +/- prednisone. * Men and Women 18 to 75 years of age. Exclusion Criteria: * Absence of a DQ mismatch to the donor. * Patient had known HLA antibodies directed to the donor antigens (pre-formed DSA) prior to transplant. * Known to be positive for donor specific anti-HLA antibodies (IgG) at time of enrollment from the most recently drawn sample. (DSA MFI\>1000 is considered positive). DSA is detected via center's standard of care test…