Abstract: FR-PO0728
Minimal Change Disease in a Patient with Type 1 Neurofibromatosis and User of Smokeless Tobacco and Cannabis: A Case Report
Session Information
- Glomerular Diseases: Membranous Nephropathy, FSGS, and Podocytopathies
October 23, 2026 | Location: Exhibit Hall A, Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Glomerular Diseases
- 1402 Glomerular Diseases: Clinical, Outcomes, and Therapeutics
Authors
- Batista, Maria Esilene Valença, Hospital das Clinicas da Universidade Federal de Pernambuco, Recife, PE, Brazil
- Gueiros, Ana Paula, Hospital das Clinicas da Universidade Federal de Pernambuco, Recife, PE, Brazil
- Costa, Denise Maria Do Nascimento, Hospital das Clinicas da Universidade Federal de Pernambuco, Recife, PE, Brazil
- Chaves, Marina Dornellas Camara de Almeida, Hospital das Clinicas da Universidade Federal de Pernambuco, Recife, PE, Brazil
Introduction
The etiology of Minimal change disease (MCD) is not yet fully understood and most cases are considered idiopathic, although some common associations that represent secondary causes have been reported. We describe a case of a patient diagnosed with MCD having a possible secondary etiology involving a genetic disorder and the use of nicotine.
Case Description
A 35-year-old man presented with progressive edema and oliguria. Laboratory tests showed serum creatinine of 4.4 mg/dL, proteinuria of 16g/24h and glomerular hematuria with blood casts present. Autoimmune markers and serological tests were negative. His pathological history included type 1 neurofibromatosis and rhinosinusitis diagnosed in adulthood. He had also been using large amount of cannabis and smokeless tobacco for about 15 and 5 years, respectively. Due to nephritic and nephrotic syndrome with worsening renal function methylprednisolone intravenous pulse therapy was administered with a maintenance dose of oral prednisone 1mg/kg/day and hemodialysis has been initiated. Improvement in renal function occurred 12 days after the start of corticosteroid therapy, without the need for further hemodialysis sessions and urine albumin-creatinine ratio of 400 mg/g. A kidney biopsy revealed 17 glomeruli with preserved cellularity, normal capillary loops and no findings in the tubules and blood vessels on light microscopy. Immunofluorescence showed only IgM trapping and electron microscopy revealed basement membrane without alterations, absence of deposits and podocyte fusion of > 90%, compatible with MCD.
Discussion
Type 1 neurofibromatosis is a genetic disorder which has podocytopathies rarely reported. One of the mechanisms related is the upregulation of the mTOR pathway caused by dysfunctional neurofibromin protein, encoded by the mutant gene NF1. The mTOR pathway influences podocyte homeostasis and it’s upregulation can lead to podocyte disfunction. Furthermore, the use of smokeless tobacco can also damage podocyte through oxidative stress and nicotine-induced activation of the NLRP3 inflammasome. In this case, the patient had two possible causes of MCD and responded well to corticosteroids, making differentiation impossible. This also raises the possibility of an epiphenomenon and highlights the need for better understanding of MCD mechanisms and biomarkers.