The genetic characteristics of adult patients with atypical hemolytic uremic syndrome in Russia

Atypical hemolytic-uremic syndrome is a rare life-threatening disease from the group of thrombotic microangiopathies, caused by the hyperactivation of the complement system. In the most cases it is associated with genetic disorders in the cluster of complement genes. Currently, a large number of different variants of the complement system genes associated with the development of aHUS are described in different countries. In our country, data on the genetic features of pediatric aHUS patients and obstetric aHUS have been published. Genetic changes in the complement system in adult aHUS patients in Russia were not so far presented. Aim: studying the genetic profile of the complement system in adult patients with aHUS. Materials and methods. The study included 20 patients with aHUS: 9 men (45%) and 11 women (55%). All patients underwent molecular-genetic analysis (search for mutations in the clinically significant part of the human genome - exome) by sequencing (Genotek laboratory). Genes CFH, CFHR1-5, CFB, CFI, DGKE, THBD, MCP, C3, С5, ADAMTS13 were analyzed. Results. Genetic variants (mutations) of the complement system associated with aHUS development were detected in 5 patients (25%). Two patients had one mutation, 2 patients - 2 and one patient - 3 mutations. In 3 patients, different genetic variants of the C3 gene were found. Two patients showed the same changes in the CFHR5 gene. In 3 patients, rare changes in the ADAMTS-13 gene, clinically associated with the development of thrombotic thrombocytopenic purpura were found. In all 20 patients, genetic variants of the complement genes with unknown clinical significance were identified, including rare variants of the C3 gene in 9 patients (45%).

атипичный гемолитико-уремический синдром, тромботическая микроангиопатия, генетические варианты системы комплемента, atypical hemolytic-uremic syndrome, thrombotic microangiopathy, genetic variants of the complement system

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