[Pathology and differential diagnosis of immunotactoid glomerulopathy]

Objective: To study the morphologic changes of immunotactoid glomerulopathy and to investigate the clinical pathological features and differential diagnosis. Methods: Renal biopsy was observed under the light microscope, immunofluorescence and electron microscopy in a case of newly diagnosed immunotactoid glomerulopathy. Results: This patient clinically presented with nephrotic syndrome and hypertension, without family history of renal diseases. Light microscopy showed that diffusely massive and specific protein deposition in the glomerulus in Masson staining. Immunofluorescence revealed IgG, C3 and κ were deposited along the capillary walls and mesangial regions. Electron microscopic examination showed that a large amount of microtubule like substances and a small amount of long bar-shaped and dense crystal-like substances were deposited in the subendothelial spaces and mesangial areas. Conclusions: Light microscopy and immunofluorescence of immunotactoid glomerulopathy show no specifically pathological changes. Under electron microscope, a large amount of microtubule like substances is deposited in the glomerulus, which is the key point to distinguish this disease from other glomerular diseases. Except for the microtubule-like substances, the present case is accompanied by the deposition of long bar-shaped and dense crystal-like substance, which has not been reported in previous studies.