Fighting aHUS Every Day

What is atypical hemolytic uremic syndrome (aHUS)?

aHUS is a genetic, chronic, ultra-rare disease that can progressively damage vital organs, such as the kidneys. aHUS is caused by genetic abnormalities that result in chronic uncontrolled complement activation, leading to complement-mediated thrombotic microangiopathy (TMA)—the formation of blood clots in small blood vessels throughout the body.1

Erica, diagnosed with aHUS at 22 years old

aHUS affects both adults and children. Patients with aHUS can face a lifelong risk of TMA, which may lead to sudden, catastrophic, and life-threatening damage to the kidney and other vital organs.1

Historically, two thirds of patients with the most common mutation required kidney dialysis, had permanent kidney damage, or died within the first year after diagnosis, despite supportive care.2,3

Symptom locations of aHUS on the human body

Symptoms of aHUS4-8

  • Confusion, stroke, or seizure
  • Heart attack
  • High blood pressure
  • Formation of blood clots in the kidney, heart, or other organs
  • Nausea and vomiting
  • Abdominal pain
  • Kidney damage


  1. Noris M, Remuzzi G. Atypical hemolytic-uremic syndrome. N Engl J Med. 2009;361(17):1676-1687.
  2. Caprioli J, Noris M, Brioschi S, et al. Genetics of HUS: the impact of MCP, CFH, and IF mutations on clinical presentation, response to treatment, and outcome. Blood. 2006;108(4):1267-1279.
  3. Loirat C, Garnier A, Sellier-Leclerc AL, Kwon T. Plasmatherapy in atypical hemolytic uremic syndrome. Semin Thromb Hemost. 2010;36(6):673-681.
  4. Jamme M, Raimbourg Q, Chauveau D, et al. Predictive features of chronic kidney disease in atypical haemolytic uremic syndrome. PLoS One. 2017;12(5):e0177894.
  5. Hofer J, Rosales A, Fischer C, Giner T. Extra-renal manifestations of complement-mediated thrombotic microangiopathies. Front Pediatr. 2014;2:1-16.
  6. Campistol JM, Arias M, Ariceta G, et al. An update for atypical haemolytic uraemic syndrome: diagnosis and treatment. A consensus document. Nefrologia. 2015;35(5):421-447.
  7. Krishnappa V, Gupta M, Elrifai M, et al. Atypical hemolytic uremic syndrome: a meta-analysis of case reports confirms the prevalence of genetic mutations and the shift of treatment regimens. Ther Apher Dial. 2018;22(2):178-188.
  8. Langman C. Systemic multi-organ complications in atypical hemolytic uremic syndrome (aHUS): retrospective study in a medical practice setting. Haematologica. 2012;97(suppl 1):195-196.

Donnan, diagnosed with aHUS at 39 years old, and his two children
I can chase my kids and play again. I think knowing what I have brings a peace to my life.”