CLINICAL IMMUNOSUPPRESSION - KIDNEY LATE

L. Rebellato¹, M. Ozawa², K. Parker³, K. Briley¹, P. Catrou⁴, P. Bolin⁵, W. Kendrick⁶, C. Haisch¹, P. Terasaki^2
1, East Carolina University, Greenville/UNITED STATES OF AMERICA, ², Terasaki Foundation Laboratory, Los Angeles/UNITED STATES OF AMERICA, ³Internal Medicine, East Carolina University, Greenville/NC/UNITED STATES OF AMERICA, ⁴, Pitt County Memorial Hospital, Greenville/UNITED STATES OF AMERICA, ⁵Internal Medicine, East Carolina University, Greenville/UNITED STATES OF AMERICA, ⁶, Eastern Nephrology & Associates, Greenville/UNITED STATES OF AMERICA

Body: Introduction: We have previously reported that DSA precedes rejection by months and that MPA dose increase reduces DSA strength. In this study, we followed patients for up to 2 years post MPA dose increase. We monitored DSA strength and total IgG levels. We hypothesized that higher MPA doses may affect DSA and total IgG levels.
Methods: Eleven stable DSA positive recipients were monitored. All recipients had an increase of at least MMF 250 mg or EC-MPS 180 mg bid, nine of which received doses equal to or greater than 720 mg bid. The maximum dose given never exceeded the manufacturer’s recommended dose. Sera were collected at the time of study enrollment and at routine clinic visits. HLA single antigen beads were used to establish DSA, strength of the antibodies measured as mean fluorescence intensity (MFI). Total serum IgG levels were measured using the Siemen’s Advia 1800. All recipients received anti-lymphocyte induction therapy. Immunosuppression consisted of a calcineurin inhibitor, prednisone, and MPA.
Results: Eight recipients had a reduction in DSA MFI varying from 20.1 to 57.2%. Seven recipients had a reduction in total IgG. Five recipients had both a reduction in DSA MFI and total IgG level.

Conclusions: MPA dose increase was associated with a reduction in DSA. The IgG finding is interesting, but more data is necessary to determine significance. We conclude that maximum tolerated MPA doses should be given in patients who develop DSA post transplant. Longer follow up is needed to determine if the achieved DSA reduction will impact long term graft survival.

Disclosure: All authors have declared no conflicts of interest.