Immunotactoid Glomerulopathy Diagnosed by a Repeat Kidney Biopsy After Initially Non-diagnostic Electron Microscopic Findings: A Case Report
Year: 2026
Type: article
Study design: Case Report
Abstract: Immunotactoid glomerulopathy (ITG) is diagnosed by identifying organized microtubules on electron microscopy and it can therefore be missed when they are not demonstrated. A 48-year-old woman with hematuria, nephrotic-range proteinuria, and a faint IgG-κ monoclonal protein underwent an initial kidney biopsy, which showed endocapillary proliferative glomerulonephritis with membranoproliferative features and scant subendothelial deposits, but no diagnostic microtubules. With worsening renal dysfunction and a limited corticosteroid response, a repeat biopsy revealed IgG3-κ-restricted deposits and non-branching, hollow-core microtubules, confirming ITG associated with monoclonal gammopathy of renal significance. Rituximab-based B cell-directed therapy was followed by sustained remission with prednisolone tapered to 2.5 mg every other day.
Source: Internal Medicine
Authors: Muneharu Yamada, Masataka Nagashima, Ken Aoki, Takahiko Hoshino, Rie Fujii, Takahiro Uchida, Yutaka Yamaguchi, Takashi Oda
Institution: Tokyo Medical University Hachioji Medical Center
Language: English
Subfield: Nephrology
Field: Medicine
Domain: Health Sciences
Open Access status: diamond
OpenAlex ID: W7211885071