Isosorbide dinitrate in nephronophthisis treatment

Nephronophthisis is a progressive disease that affects development of the renal tubules and leads to end stage renal disease. Many affected children have isolated renal disease; however, there can be additional manifestations including heart defects, liver fibrosis, brain malformations, and situs inversus. There is no way to slow or modify the disease. We describe a patient who presented at birth with cholestatic jaundice and decreased kidney function, found by exome sequencing to have two NPHP3 variants. Her clinical status deteriorated rapidly, and two disease-modifying agents were given in hopes of slowing disease progression, the arginine vasopressin type II receptor antagonist tolvaptan to stabilize her renal function and isosorbide dinitrate to manage her poorly controlled hypertension. Tolvaptan therapy initiated at 82 days of life had limited effect on the rate of decline in renal function and was insufficient to abrogate the need for dialysis; however, isosorbide dinitrate therapy led to a dramatic improvement in blood pressure control and allowed for the discontinuation of multiple anti-hypertensive agents. This is the first report of the use of tolvaptan and isosorbide dinitrate for nephronophthisis management. We suggest that isosorbide dinitrate may represent a disease-modifying agent in nephronophthisis treatment.