Introduction:
Podocyte infolding Glomerulopathy (PIG) is a rare and newly recognized pattern of glomerular injury, characterized by microspheres or microtubular structures within the glomerular basement membrane, associated with podocyte cytoplasmic process infolding. Its clinical significance remains uncertain, and it is unclear whether PIG represents a distinct disease entity or a morphological manifestation of other conditions.
Methods:
A retrospective study was conducted on renal biopsies performed between May 2016 and May 2022 at a single center in South India. Biopsies underwent light microscopy, immunofluorescence, and electron microscopy. Renal biopsy features and clinical data were reviewed.
Results:
PIG was identified in 65 of 3,124 biopsies (2.08%). The mean age was 54.35 ± 8.14 years. All cases presented with isolated PIG devoid of immune deposits on immunofluorescence. Diabetes mellitus was a consistent comorbidity (100%), frequently accompanied by hypertension (93.84%). Clinical presentations included nephrotic syndrome (18.46%) and renal dysfunction (81.53%) with microhematuria or rapid progression. Diabetic Nephropathy (DN) was the primary diagnosis: DN Class III (55.38%), Class IV (35.38%), and Class II (9.23%). Histopathology uniformly showed Type C PIG with subepithelial microspherules, and 21.53% exhibited concomitant diabetic fibrillosis
Conclusions:
PIG is closely associated with diabetes mellitus, presenting a consistent pattern devoid of immune deposits. Its frequent occurrence alongside diabetic fibrillosis suggests a potential pathognomonic link, warranting further research to elucidate its clinical significance and implications for the management of diabetic kidney disease.
I have no potential conflict of interest to disclose.
I did not use generative AI and AI-assisted technologies in the writing process.