Abstract
Background: Proliferative glomerulonephritis with monoclonal IgG deposits (PGNMID) is
a newly described and rare entity that can develop in native and very rarely in transplanted
kidneys. We present a patient who developed de novo PGNMID in the kidney allograft
along with a review of the literature.
Case Presentation: A 38-year old female with type 1 diabetes who underwent successful
simultaneous pancreas-kidney (SPK) transplantation 6 years earlier presented with rising
serum creatinine, nephrotic range proteinuria and microhematuria. She underwent
extensive work up and kidney allograft biopsy revealed mesangial expansion and
hypercelluarity on light microscopy, mesangial staining for IgG3, kappa light chains, C1q
and C3 on immunofluorescence and abundant mesangial electron dense deposits without
substructures on electron microscopy. Serum and urine immunofixation electrophoresis
were negative. A diagnosis of de novo PGNMID was made. Patient’s proteinuria improved
and serum creatinine stabilized with conservative therapy.
Conclusions: PGNMID can rarely develop in kidney allograft as recurrent or de novo disease
and may be mislabeled as transplant glomerulopathy if careful immunofluorescence and
electron microscopy are not performed on biopsy specimens. Further studies are needed
to better understand the pathogenesis of this disease entity and to develop optimal
therapeutic approaches.