title: Juvenile elastic arteries after 28 years of renal replacement therapy in a patient with complete complement C4 deficiency.
abstract: BACKGROUND
  Complement activation products are present in atherosclerotic plaques. Recently, binding of complement to elastin and collagen in the aortic wall has been demonstrated, suggesting a role of complement in the development aortic stiffness and atherosclerosis. The definitive role of complement in atherosclerosis and arteriosclerosis, however, remains unclear.
  
  
  METHODS
  We here describe a patient with hereditary complete deficiency of complement C4 suffering from Henoch-Schoenlein purpura and on renal replacement therapy for twenty-eight years. The patient had the full range of risk factors for vascular damage such as hypertension, volume overload, hyperphosphatemia and hyperparathyroidism. Despite that, his carotid artery intima media thickness was below the normal range and his pulse wave velocity was normal. In contrast, the patient's coronary and peripheral muscular arteries were heavily calcified.
  
  
  CONCLUSIONS
  This case supports the hypothesis that complement plays an important role in the development of stiffness of elastic arteries. We speculate that inability to activate complement by the classical or lectin pathways protected the patient from atherosclerosis, arteriosclerosis, stiffening and calcification of the aorta and carotid arteries. Inhibition of complement activation may be a potential target for prophylactic and therapeutic interventions.
authors.affiliation: Department of Nephrology and Dialysis, Feldkirch Academic Teaching Hospital, Carinagasse 47, Feldkirch 6800, Austria. florian.knoll@lkhf.at
authors.forename: Florian
authors.initials: F
authors.lastname: Knoll
authors.forename: Emanuel
authors.initials: E
authors.lastname: Zitt
authors.forename: Denis
authors.initials: D
authors.lastname: Intemann
authors.forename: Karl
authors.initials: K
authors.lastname: Lhotta
mesh_terms: D050197:Atherosclerosis / Q000175:diagnosis* / Q000235:genetics / Q000503:physiopathology*; D003181:Complement C4 / Q000172:deficiency* / Q000235:genetics; D003171:Complement Pathway, Classical / Q000235:genetics; D037582:Complement Pathway, Mannose-Binding Lectin / Q000235:genetics; D004548:Elasticity / Q000502:physiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D017582:Renal Replacement Therapy / Q000009:adverse effects* / Q000639:trends; D013997:Time Factors; D059289:Vascular Stiffness / Q000235:genetics*
chemical_list: D003181:Complement C4