Hemolytic uremic syndrome with central nervous system manifestations, a case report and literature review

Hemolytic uremic syndrome (HUS) is a multisystem disorder generally seen in children and young adults, manifesting with the symptomatic triad of thrombocytopenia, hemolytic anemia, and acute kidney injury. These symptoms are often preceded by a prodrome of bloody diarrhea, vomiting, fever, and weakness. HUS is an exceedingly rare entity, with less than 1.5 per 100,000 people affected annually. HUS with central nervous system (CNS) manifestations constitutes approximately 20%-50% of cases and often presents with seizures, altered level of consciousness, and brainstem symptoms. CNS involvement in HUS is a major cause of acute morbidity and mortality; therefore, timely diagnosis and treatment are crucial in the management of these cases. Neuroimaging plays a critical role in the diagnosis; however, it might be very challenging in a large number of cases because studies that report the typical neuroradiologic features of brain injury in cases with HUS are not commonly available. Herein, we demonstrate in a case-based approach, the importance of combining clinical suspicion with different radiologic modalities to better characterize HUS cases with CNS involvement, as well as demonstrate how the early start of meticulous supportive therapy can lead to a favorable outcome even when severe brain involvement is evident on acute imaging studies. Furthermore, we provide an illustrated overview of the current theories that explain the neurologic involvement in HUS, as well as the commonly affected brain areas and how this entity can be radiologically differentiated from other potential diagnoses.