Favorable therapeutic efficacy of low‐density lipoprotein apheresis for nephrotic syndrome with impaired renal function

Many reports have shown the therapeutic efficacy of LDL apheresis (LDL‐A) in drug‐resistant nephrotic syndrome (NS) for improvement of heavy proteinuria and severely impaired renal function. To obtain comprehensive results in a large number of cases, a post hoc analysis of the Prospective Observational survey on the Long‐Term Effects of the LDL‐Apheresis on the Drug Resistant Nephrotic Syndrome (POLARIS) study was performed by stratifying enrolled cases according to the pretreatment estimated glomerular filtration rate (eGFR) levels indicating normal (N) (≥60 ml/min/1.73 m(2)), moderately impaired (M) (≥30 to <60 ml/min/1.73 m(2)), and severely impaired (S) (<30 ml/min/1.73 m(2)) renal function. Significant improvements of proteinuria and renal function were found in Group N and, most interestingly, in Group M. A tendency for improvement in proteinuria was found in Group S. Most cases in all groups had not entered end‐stage renal disease at 2 years after LDL‐A treatment. These results suggest that LDL‐A has therapeutic efficacy even in cases in which renal function has declined to 30 ml/min/1.73 m(2).