The use of the drug Elizaria – a biosimilar of the original eculizumab in atypical hemolytic-uremic syndrome due to mutation of the С3 gene in children: clinical observation and literature review

   This article presents the features of atypical haemolytic-uremic syndrome (ORPHA 544472) in children. Atypical haemolytic-uremic syndrome (aHUS) is defined by a triad: haemolytic anaemia, thrombocytopenia and acute kidney injury in pediatric and adult patients. The OMIM catalogue presents the phenotypic series of aHUS with mutations of the C3, CFB, CFH, CFHR1, CFHR3, DGKE, MCP, THBD genes. Atypical haemolytic-uremic syndrome is often associated with gene mutations in proteins and activators that regulate complement. We report the case of a girl who had a manifestation of aHUS at 8 years 5 months of age and a severe relapse at 8 years 10 months of age. The relapse was characterised by manifestations of haemolytic anaemia, thrombocytopenia, acute renal damage, severe arterial hypertension, high lactate dehydrogenase and membrane attack complex levels and low C3 component. After 5 courses of haemodialysis, 3 haemodiafiltration, diuresis increased and biochemical parameters improved. We presented with ASUS in a child associated with a p.Cys1101Tyr C3 gene mutation. We used a complement inhibitor, Elizaria®, a biosimilar to the original drug eculizumab, to treat a child with atypical haemolytic-uremic syndrome due to the C3 gene mutation. The complement system inhibitor therapy with Elizaria preserved the health and life of a sick girl with a severe relapse of aHUS.