BACKGROUND
Atypical hemolytic uremic syndrome (aHUS) is a set of heterogenous disorders of
thrombotic microangiopathy defined by
thrombocytopenia,
hemolytic anemia, and
acute renal failure that is not mediated by
shiga toxin.
Factor Eight Inhibitor Bypassing Activity (
FEIBA) is a concentrate of inactivated and activated
coagulation factors that is approved for use to establish hemostasis in patients with
hemophilia or acquired factor inhibitors. However, it has recently been used off-label as an
anticoagulant reversal therapy among the general population. Additionally, post-market surveillance has shown increased thromboembolic adverse events, whereas micro-thrombotic complications are rarely described. CASE REPORT A 58-year-old man with a history of
hypertension and a single
deep vein thrombosis on
warfarin presented with right upper-quadrant tenderness extending to the right flank. He was found to have a hepatic
hematoma and was given activated
prothrombin complex concentrate (aPCC) of 14 150 units of
anti-inhibitor coagulant complex at 100 units per kilogram due to concern for active
hemorrhage. Subsequently, he developed
anemia,
thrombocytopenia, and
renal failure consistent with atypical HUS. He was treated with
hemodialysis,
corticosteroids,
plasma exchange, and 4 weekly doses of the anti-C5 antibody
eculizumab. The patient subsequently recovered, demonstrating improved
hemoglobin,
creatinine, and platelets. He eventually achieved
hemodialysis independence. Follow-up showed no evidence of recurrent atypical HUS and the patient has not needed maintenance
eculizumab. CONCLUSIONS Herein, we report the first case of aHUS associated with administration of a single large dose of aPCC for
anticoagulation reversal. We postulate a potential mechanism for
FEIBA-induced aHUS and report the efficacy of a short trial of
eculizumab.