Thrombotic microangiopathy as a complication in a patient with focal segmental glomerulosclerosis

Abstract

We report on a 12-year-old female patient with steroid-dependent nephrotic syndrome due to focal segmental glomerulosclerosis (FSGS) since her 3rd year of life. She was twice treated with oral cyclophosphamide and received antihypertensive treatment with atenolol and enalapril. After 3 years without any control or therapy, she presented in a reduced general condition with hypertensive crisis and a blood pressure of 220/130 mmHg, headache, vomiting and loss of vision. Additionally, renal insufficiency (creatinine 11.4 mg/dl, urea 157 mg/dl), with oliguria, anaemia and a severe relapse of nephrotic syndrome, was present. Initial treatment with steroids, albumin-furosemide infusions and antihypertensive drugs was unsuccessful, and dialysis treatment was necessary. Renal biopsy showed an advanced stage of the known FSGS and, surprisingly, a thrombotic microangiopathy. Further diagnostic investigations revealed no signs of haemolytic-uraemic syndrome, but echocardiography showed left ventricular hypertrophy, and hypertensive retinopathy grade 3 was diagnosed, making severe hypertension the most likely reason for the thrombotic microangiopathy. While adequate antihypertensive treatment led to regress of left ventricular hypertrophy and hypertensive retinopathy, renal function did not recover, and the patient remained dialysis-dependent. In conclusion, severe hypertension in chronic kidney disease can lead to target organ damage and thrombotic microangiopathy, which may further worsen renal function.