A mutation in CFHR5, a member of the complement factor H family of genes that regulate complement activation, was recently shown to cause isolated C3 glomerulopathy, presenting with MH in childhood and demonstrating a significant risk for CKD/ESKD after 40 years old.
In addition, a heterozygous mutation (causing an S890I change) in factor H of complement was found in the patient who developed chronic renal failure but not in her sister, who presented with exclusive neurologic symptoms.
The risk of rapid loss of renal function in patients with functional mutations in factor H requires that effective treatment be initiated as soon as possible, but identification of these patients relies on genetic studies that are time consuming.
Our 23-year follow-up of a population of severely affected children with infection-mediated HUS demonstrates a high percentage of chronic kidney disease and end-stage kidney disease (19%).