Introduction:
Membranous nephropathy, an important cause of adult nephrotic syndrome, is a disorder of IgG immune complex-based thickening of the glomerular capillary wall. This leads to podocyte structural damage and proteinuria. Being autoimmune in origin, podocytes are the source of autoantigens and the target of circulating autoantibodies. Though the definitive diagnosis is made by typical histopathological findings on kidney biopsy, PLA2R antibody positivity is a useful diagnostic marker for its diagnosis. In present day scenario, it eliminates the need of biopsy. The present study describes the clinical detail, treatment profile, and outcomes of patients with PLA2R-positive membranous nephropathy.
Methods:
The study included the data of primary membranous nephropathy based on tissue or serum PLA2R positivity with or without supportive histopathology findings from Jan 2019 to July 2022 collected both retrospectively and prospectively. The patients with secondary membranous nephropathy were excluded. The date of the kidney biopsy was considered to be month 0- (date of diagnosis), and subsequent data collection was based on this date. Serial data was collected at diagnosis 3, 6, and 12 months, then every 3-6 months based on remission status and patient’s follow-up. The data was entered in Microsoft excel 2016 and was analysed using STATA13 software.
Results:
Seventy nine patients were enrolled in the study with a mean age±SD of 47.61±15.1 years and GFR of 89.88±7.97 ml/min per 1.73 m2. The majority were males. The clinical presentation included swelling bilateral lower limbs (45.5%), anasarca (21.55), and frothy urine (8.8%). Among the patients with positive tissue PLA2R, IgG4 and IgG3 positivity was present in 98% and 43% patients respectively. Treatment options included modified Ponticelli regimen (67.1%) and rituximab (26.9%). Follow-up records were available in 64 patients with a median (IQR) duration of 30 (21.25, 43) months. The complete and partial remission was seen in 62.5% and 21.9% of the patients respectively. Renal dysfunction was present in 5 patients. Four patients developed relapse after treatment and 3 were treated with modified Ponticelli treatment while one received Rituximab. Of these 3 developed complete remission and one had partial remission.
Conclusions:
Patients with PLA2R positive membranous nephropathy have overall good prognosis with less renal dysfunction and good response to the treatment options available even in resource limited settings. Our study has taken only PLA2R-positive patients, and the rest were excluded. The limitations of our study were small sample size, few investigations were not available at baseline, and there were few patients for which we were not able to retrieve the whole of the data. Even the follow-up PLA2R levels were not available. Larger studies are needed with prolonged follow up to determine the long term outcomes in these patients.
I have no potential conflict of interest to disclose.
I did not use generative AI and AI-assisted technologies in the writing process.