Compared staining of the phospholipase A2 receptor in the glomeruli of Chinese adults and children with idiopathic membranous nephropathy

Background: The identification of the M-type phospholipase A2 receptor (PLA2R) is a breakthrough recognized as a major target for adults with idiopathic membranous nephropathy (IMN). However, the role PLA2R played in pediatric patients with IMN, particularly in Chinese, has yet to be determined. Methods: This retrospective study included 187 adult patients and 38 pediatric patients aged 17 years or younger with biopsy proved IMN. The pediatric cohort consisted of 27 children aged from 1 to 12 years and 11 children aged from 13 to 17. Glomerular expression of PLA2R was analyzed in stored, formalin-fixed, paraffin-embedded kidney biopsy sections. Results: PLA2R staining in glomerular deposits was observed in 82.7% and 42.1% of adult and pediatric patients with IMN, respectively. The PLA2R-positive staining patients with IMN presented with more severe clinical features than PLA2R-negative staining patients in both adult and pediatric cohorts. When compared to the young children patients with IMN, the adolescents exhibited a higher positive rate of PLA2R staining (81.8% versus 25.9%), similar to the adult patients. Conclusion: The clinical features and prevalence of PLA2R positive staining in adolescent patients with IMN were similar to adult patients, suggesting that they probably have a close etiology and pathogenesis. However, most of the young children patients with IMN were PLA2R negative staining, suggesting a different underlying etiology.