Clinicopathological features and outcomes of PLA2R-related membranous nephropathy with renal glycosuria.

Background: Membranous nephropathy (MN) is an immune complex-mediated disease. Massive proteinuria can lead to Fanconi syndrome, clinically manifesting as renal glycosuria. The prevalence and prognosis of M-type phospholipase A2 receptor (PLA2R)-related MN with renal glycosuria remain unknown.

Materials and methods: Patients diagnosed with PLA2R-related MN with renal glycosuria were reviewed, and the control group comprised patients with MN without renal glycosuria who were randomly selected at a ratio of 1 : 3.

Results: 50 patients diagnosed with PLA2R-related MN with renal glycosuria from January 2015 to January 2020 were included, with a prevalence of 2.3%. Compared with patients without renal glycosuria, those with renal glycosuria exhibited greater proteinuria, lower estimated glomerular filtration rate (eGFR), and higher use of diuretics, anticoagulants, antibiotics, traditional Chinese medicine, and tacrolimus within 3 months prior to renal biopsy (all p < 0.05). Histologically, patients with renal glycosuria exhibited more severe pathological stages, acute/chronic tubulointerstitial lesions, and tubulointerstitial inflammation (all p < 0.05). Of the 10 patients treated with rituximab (RTX), proteinuria remission was maintained in 6 (60%) patients, and urine glucose remission was achieved in 5 of these 6 patients (83.3%). Multivariate Cox regression analysis showed that renal glycosuria and age > 50 years were independent risk factors for end-stage renal disease (ESRD) or a 30% reduction in the eGFR in patients with PLA2R-related MN.

Conclusion: PLA2R-related MN patients with renal glycosuria presented with more severe clinicopathological manifestations and worse prognoses. Nephrotoxic drugs should be administered rationally, and RTX should be considered as a promising treatment option.