Open AccessCalcineurin inhibitor induced nephrotoxicity in steroid resistant nephrotic syndrome
Author(s) -
Aditi Sinha,
Amita Sharma,
Ankit Mehta,
Ruchika Gupta,
Ashima Gulati,
Pankaj Hari,
AK Dinda,
Arvind Bagga
Publication year - 2013
Publication title -
indian journal of nephrology/indian journal of nephrology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.317
H-Index - 24
eISSN - 1998-3662
pISSN - 0971-4065
DOI - 10.4103/0971-4065.107197
Subject(s) - medicine , nephrotoxicity , nephrotic syndrome , focal segmental glomerulosclerosis , tacrolimus , calcineurin , urology , gastroenterology , interquartile range , renal biopsy , nephrology , proteinuria , renal function , kidney , transplantation
Prolonged therapy with calcineurin inhibitors (CNI) is effective in patients with difficult nephrotic syndrome. However, information on prevalence and risk factors for nephrotoxicity in children with steroid-resistant nephrotic syndrome is limited. This retrospective observational study was conducted on 40 patients with steroid-resistant nephrotic syndrome treated with cyclosporine (CyA) (n = 28) or tacrolimus (n = 12) for more than 2 years. Nephrotoxicity was defined by the presence of striped fibrosis involving ≥10% of the interstitium or nodular hyalinosis in more than one arteriole. Ten additional parameters were graded semi-quantitatively. Continuous data are presented as median and interquartile range (IQR). The median (IQR) age at onset of nephrotic syndrome and CNI therapy were 30 (21-45) and 49.5 (40-102.5) months. A second renal biopsy, following 30 (26-35) months of CNI therapy, showed histological toxicity in 10 (25%) patients. Toxicity was seen in 7 and 3 patients receiving CyA and tacrolimus, respectively, and 5 patients each with minimal change and focal segmental glomerulosclerosis. Therapy with CNI was associated with significant increases in scores for global glomerulosclerosis, tubular atrophy, interstitial fibrosis, nonnodular arteriolar hyalinosis (P < -0.001 for all), arteriolar smooth-muscle vacuolization (P = -0.02), juxtaglomerular hyperplasia (P = -0.002), and tubular microcalcinosis (P = -0.06). Risk factors for nephrotoxicity were initial resistance (OR 9; 95% CI 1.0-80.1; P = -0.049); dose of CyA (OR 9.2; 95% CI 1.1-74.6; P = -0.037); duration of heavy proteinuria (OR 1.2; 95% CI 1.0-1.4; P = -0.023); and hypertension during therapy (OR 6; 95% CI 1.3-28.3; P = -0.023). Following prolonged CNI therapy, one in four biopsies show features of toxicity. Prolonged duration of heavy proteinuria, hypertension, initial steroid resistance and high CyA dose predict the occurrence of nephrotoxicity.