Atypical hemolytic uremic syndrome (aHUS) is a systemic, life-threatening thrombotic microangiopathy characterized by microangiopathic hemolytic anemia, thrombocytopenia and organ damage. Cardiovascular involvement is described up to 43%. Hemodialysis discontinuation is described to occur in 80% of cases after therapy with eculizumab, but few data on long term discontinuation are available.
We describe a case of a 53 year old caucasian man with aHUS and oliguric renal failure requiring renal replacement therapy. At admission the echocardiogram EC was normal with fractional ejection of 65%. The renal biopsy disclosed severe thrombotic microangiopathy. He developed hypertension controlled with betablockers, diuretics, and calcium channel blockers. PEX was performed unsuccessfully.
The activity of ADAMTS 13 was normal. Molecular analyses of complement genes was carried out, identifying mutations in the CHF gene (N516K) and the MCP gene (c.286+2T>G). The average serum creatinine was 7.0 mg/dl, with a daily urine output of approx. 500 ml. Two months later, he gradually developed cardiac failure up to class NYHA III. (EC showed significant dilation and dysfunction of the left ventricle with FE 25%). Eculizumab was given and after two months of treatment, urine volumes gradually increased and the frequency of HD was reduced from three to twice per week. He was still in NYHA III, with slight overhydration. After eight months, diuresis had recovered and HD was discontinued. NYHA class was II. Repeated ECs disclosed a gradual improvement of FE.At last visit the average serum creatinine was 2.7 mg/dl, and FE 45%.
Based on these results, we suggest that in our case, prolonged treatment with eculizumab allowed discontinuation of dialysis and improvement of heart failure.
