Atypical hemolytic-uremic syndrome(a HUS) is a rare disease of complement dysregulation leading to thrombotic microangiopathy(TMA). Renal involvement and progression to end-stage renal disease are common in untreated ...Atypical hemolytic-uremic syndrome(a HUS) is a rare disease of complement dysregulation leading to thrombotic microangiopathy(TMA). Renal involvement and progression to end-stage renal disease are common in untreated patients. We report a 52-year-old female patient who presented with severe acute kidney injury, microangiopathic hemolytic anemia, and thrombocytopenia. She was managed with steroid, plasma exchange, and dialysis. Kidney biopsy shows TMA and renal cortical necrosis. Genetic analysis reveals heterozygous complement factor Ⅰ(CFI) mutation. Eculizumab was initiated after 3 mo of presentation, continued for 9 mo, and stopped because of sustained hematologic remission, steady renal function, and cost issues. Despite this, the patient continued to be in hematologic remission and showed signs of renal recovery, and peritoneal dialysis was stopped 32 mo after initiation. We report a case of a HUS due to CFI mutation, which, to the best of our knowledge, has not been reported before in Saudi Arabia. Our case illustrates the challenges related to the diagnosis and management of this condition, in which a high index of suspicion and prompt treatment are usually necessary.展开更多
Complement is a humoral factor of innate immunity and plays important roles in immune surveillance and clearance of invading pathogens.This system is directly and immediately activated in an immune-competent host,and ...Complement is a humoral factor of innate immunity and plays important roles in immune surveillance and clearance of invading pathogens.This system is directly and immediately activated in an immune-competent host,and the alternative(antibody-independent),Lectin(triggered by mannose-binding lectin) and classical pathways(antibody-dependent) have been described in fish.All three pathways converge to the lytic pathway,leading to opsonization or direct killing of the microorganism.The alternative and lectin pathways are ancient mechanisms present in invertebrates as well as ancient vertebrates.Some of the agents,like zymosan and LPS(lipopolysaccharide),are known activators of the alternative pathway of fish complement.The lectin pathway,which has not been much studied in teleosts,is activated by the binding of mannose on the surface of microorganisms to a complex of mannose-binding lectin(MBL) and MBL-associated serine protease(MASP).Fish complements are comparable to those of mammals but some important differences have been described.Fish serum shows hemolytic activity indistinguishable from that of mammalian complement.In general the complement system of the alternative pathway is more active in fish than in mammals,is not heat labile and therefore difficult to preserve.Fish complement has lower optimum reaction temperature than its mammalian counterpart,and its components,like C3.The complement system is composed of numerous proteins and all pathways generate factor C3,which has been described and isolated from teleost species.Complement C3 is a central molecule in the complement system whose activation is essential for all the important functions performed by this system.Complement proteins in fish,like C3 and B factor,are more polymorphic.Here we describe some characteristics of the complement system of fish.展开更多
文摘Atypical hemolytic-uremic syndrome(a HUS) is a rare disease of complement dysregulation leading to thrombotic microangiopathy(TMA). Renal involvement and progression to end-stage renal disease are common in untreated patients. We report a 52-year-old female patient who presented with severe acute kidney injury, microangiopathic hemolytic anemia, and thrombocytopenia. She was managed with steroid, plasma exchange, and dialysis. Kidney biopsy shows TMA and renal cortical necrosis. Genetic analysis reveals heterozygous complement factor Ⅰ(CFI) mutation. Eculizumab was initiated after 3 mo of presentation, continued for 9 mo, and stopped because of sustained hematologic remission, steady renal function, and cost issues. Despite this, the patient continued to be in hematologic remission and showed signs of renal recovery, and peritoneal dialysis was stopped 32 mo after initiation. We report a case of a HUS due to CFI mutation, which, to the best of our knowledge, has not been reported before in Saudi Arabia. Our case illustrates the challenges related to the diagnosis and management of this condition, in which a high index of suspicion and prompt treatment are usually necessary.
文摘Complement is a humoral factor of innate immunity and plays important roles in immune surveillance and clearance of invading pathogens.This system is directly and immediately activated in an immune-competent host,and the alternative(antibody-independent),Lectin(triggered by mannose-binding lectin) and classical pathways(antibody-dependent) have been described in fish.All three pathways converge to the lytic pathway,leading to opsonization or direct killing of the microorganism.The alternative and lectin pathways are ancient mechanisms present in invertebrates as well as ancient vertebrates.Some of the agents,like zymosan and LPS(lipopolysaccharide),are known activators of the alternative pathway of fish complement.The lectin pathway,which has not been much studied in teleosts,is activated by the binding of mannose on the surface of microorganisms to a complex of mannose-binding lectin(MBL) and MBL-associated serine protease(MASP).Fish complements are comparable to those of mammals but some important differences have been described.Fish serum shows hemolytic activity indistinguishable from that of mammalian complement.In general the complement system of the alternative pathway is more active in fish than in mammals,is not heat labile and therefore difficult to preserve.Fish complement has lower optimum reaction temperature than its mammalian counterpart,and its components,like C3.The complement system is composed of numerous proteins and all pathways generate factor C3,which has been described and isolated from teleost species.Complement C3 is a central molecule in the complement system whose activation is essential for all the important functions performed by this system.Complement proteins in fish,like C3 and B factor,are more polymorphic.Here we describe some characteristics of the complement system of fish.
