Incidence and Severity of Extra-Kidney Manifestations and Outcomes in Pediatric Hemolytic Uremic Syndrome: A Retrospective Cohort Study

Background: Hemolytic uremic syndrome (HUS) is a relatively uncommon disease amongst children with an annual incidence rate of 5.08 per 100,000. Through data analysis gathered using an electronic health record (EHR), we aimed to assess incidences of extra-renal manifestations involved with HUS, explore clinical outcomes, and conduct an epidemiological analysis on the renal profiles of these patients. Methods: An observational, retrospective analysis was conducted using the data analytics program TriNetX. We assessed the cumulative incidence and 1-year mortality risk of extra-renal manifestations of hemolytic uremic syndrome (HUS) in pediatric patients at 3-, 6- and 12-months following diagnosis: hypertension, noninfective colitis, acute upper respiratory tract infections, disorders of GI tract, GERD, pulmonary edema and ARDS, epilepsy, heart disease, stroke, muscular disorders, and abnormal serum enzyme levels. We also analyzed clinical outcomes (incidence of ICU admissions, mechanical ventilation, hospitalizations, emergency department (ED) visits), mortality, and treatment over a 1-year follow-up period and the progression of overall kidney disease. Results: Hypertensive diseases were the most prevalent cumulative incidence outcome, with a cumulative incidence of 25.7% and a survival probability of 70.4% at 1-year post-diagnosis. At 1-year post HUS diagnosis, 44/2,142 (2.1%) patients were deceased, 460/2,142 (21.5%) patients had an ED visit, 760/2,142 (35.5%) patients were hospitalized, 137/2,142 (6.4%) patients were admitted to the ICU, and 171/2,142 (8.0%) patients were mechanically ventilated/intubated. At 1-year post diagnosis in pediatric HUS patients 154/2,142 (7.2%) patients received treatment with Eculizumab, 86/2,142 (4.0%) patients received a transfusion of non-autologous platelets, and 248/2,142 (11.6%) patients ended up receiving hemodialysis. At 1-year post HUS diagnosis, 726/2,142 (34.0%) patients developed AKI and 85/2,142 (4.0%) patients developed ESRD. 323/2,142 (15.1%) patients developed CKD. Conclusion: We present short term outcomes of pediatric HUS from a large database, including novel findings of the rates of hospitalization and ED visits, outcome of hypertension and extrarenal manifestations, as well as mortality and kidney disease progression over 1-year follow-up.