Atypical hemolytic-uremic syndrome (aHUS) results from excessive, uncontrolled activation of the alternative pathway of the complement system. It is important to distinguish aHUS from other thrombotic microangiopathies. The aim of this paper is to discuss the complexity and relevance of the genetic background of aHUS patients. The review discusses the genetic variants that are important for diagnosis, treatment and prognosis of patients, which is inevitably important for the qualification of patients for treatment with eculizumab. These variants are not only found in the genes involved in the control of complement system but are also related to the coagulation system. The paper emphasizes the diagnostic difficulties resulting from the extremely diverse genetic background of the patients. It is important to conduct further genetic studies of aHUS patients, also paying attention to genes unrelated to the complement system. The paper contains information on the role of genetic predisposition in tailoring the risk for aHUS and determining its clinical outcome, including qualification for eculizumab therapy.
Keywords: aHUS; complement system; eculizumab; thrombotic microangiography; genetics.