Abstract: PUB200
Isolated Immunotactoid Glomerulonephritis Without Systemic Hematologic Disease
Session Information
Category: Onconephrology
- 1600 Onconephrology
Authors
- Dade, Eliezer, Broward Health North, Deerfield Beach, Florida, United States
- Aviles Riascos, Cinthya Carolina, Broward Health North, Deerfield Beach, Florida, United States
- Eftekhari, Parham, Broward Health North, Deerfield Beach, Florida, United States
Introduction
Immunotactoid Glomerulonephritis is a rare glomerular disease characterized by parallelly arranged microtubular immunoglobulin deposits measuring 14–60 nm in diameter and is commonly associated with lymphoproliferative or monoclonal disorders. Cases without detectable systemic hematologic disease are uncommon and diagnostically challenging. We present a case of isolated immunotactoid glomerulonephritis with monotypic IgG2 lambda deposits in the absence of identifiable hematologic disease.
Case Description
A young African American woman with no prior kidney disease presented with newly diagnosed CKD stage 2 and persistent sub-nephrotic proteinuria. Serologic workup, including complement, autoimmune, and infectious testing, was unrevealing. Given persistent proteinuria, a kidney biopsy was performed and demonstrated focal segmental endocapillary proliferative and membranous glomerulonephritis with monotypic IgG2 lambda microtubular deposits consistent with Immunotactoid Glomerulonephritis. Bone marrow biopsy and PET imaging showed no evidence of monoclonal gammopathy or lymphoproliferative disease. Despite no detectable systemic clone, concern remained for a renal monoclonal process. The patient was treated with Rituximab and subsequently showed improvement in proteinuria with stable renal function.
Discussion
This case represents an uncommon presentation of monoclonal gammopathy of renal significance manifesting as immunotactoid glomerulonephritis in the absence of identifiable systemic hematologic disease. The presence of monotypic IgG2 lambda microtubular deposits supports an underlying monoclonal process despite normal bone marrow and imaging studies. Prominent C3 staining suggests complement pathway involvement, a feature increasingly recognized in MGRS-associated kidney disease. Management remains challenging in patients with preserved renal function and no detectable clone. In this case, the patient was ultimately treated with Rituximab and demonstrated net improvement in proteinuria. Careful longitudinal surveillance remains essential, as an underlying hematologic disorder may emerge over time.