IFNB1 and myeloid sarcoma: Renal thrombotic microangiopathy (TMA) was the next most prevalent renal disease identified and was secondary to IFN-β treatment.[15,18–20] However, 2 cases progressed to chronic kidney disease even after IFN β was discontinued.[15,19] Other renal pathologies included acute renal failure from nephrogenic lower urinary tract dysfunction,[10] and nephrolithiasis[1] found among MS patients.