Treatment of c4d-positive acute humoral rejection with plasmapheresis and rabbit polyclonal antithymocyte globulin

Alloantibody-mediated acute rejection is a major cause of renal allograft loss despite aggressive therapy. Patients with humoral rejection can be identified with high sensitivity and specificity by the presence of peritubular capillary C4d staining on renal biopsy and donor-specific anti-human leukocyte antigen antibodies. Standard therapy for acute humoral rejection (AHR) has been removal of donor-specific antibodies by plasmapheresis (PPH) in conjunction with intravenous immunoglobulin therapy. We describe a series of seven patients with C4d positive AHR who received combined therapy with PPH and polyclonal rabbit antithymocyte globulin (rATG). PPH (1.4 volume exchange) was initiated on diagnosis of AHR on an alternate day basis for a mean number of 6.8 treatments, in conjunction with rATG (0.75 mg/kg/day 5-10 days) until the serum creatinine returned to 120% of nadir. The nadir posttreatment creatinine was significantly lower than pretreatment creatinine (1.0+/-1.2 vs. 2+/-1.4, P