Recurrent ocular involvement in pediatric atypical hemolytic uremic syndrome.

Atypical hemolytic uremic syndrome (HUS) is a subtype of thrombotic microangiopathy associated with complement alternative pathway dysregulation. It is clinically characterized by a relapsing course and a poor prognosis. Multiple organ systems are commonly affected by thrombotic microangiopathy in pediatric atypical HUS; however, ocular involvement is rarely reported. The case of an 11-year-old girl diagnosed as having atypical HUS who presented with bilateral central retinal vein occlusions with macular subhyaloid hemorrhage during her initial onset and ophthalmoplegia, diplopia, and optic disc edema during her relapsing episode 1 year later is described. All ocular manifestations occurred in the convalescence phase of atypical HUS. No other extrarenal complications were found and full recovery was achieved following typical treatment for atypical HUS (ie, plasma infusion, steroid, and supportive therapy). This is thought to be the first reported case of recurrent ocular involvement in pediatric atypical HUS.