1/50. Systemic lupus erythematosus-associated catastrophic antiphospholipid syndrome occurring after typhoid fever: a possible role of Salmonella lipopolysaccharide in the occurrence of diffuse vasculopathy-coagulopathy.We report a case of well-documented typhoid fever in a 30-year-old woman with inactive systemic lupus erythematosus with asymptomatic lupus anticoagulant and high-titer anticardiolipin antibody (aCL). Despite prompt eradication of the salmonella typhi obtained with appropriate antibiotic therapy, multiple organ system dysfunction occurred. The central nervous system was involved, with ischemic infarcts in the occipital lobes. High-dose corticosteroid therapy failed to improve the neurologic manifestations, which responded to repeated plasmapheresis. A sharp fall in aCL and anti-beta2-glycoprotein I antibody titers was recorded before the start of plasmapheresis. At the same time, IgM and IgG antibodies to Salmonella group O:9 lipopolysaccharide became detectable; the IgM antibodies disappeared within 4 months, whereas the IgG antibodies remained detectable during the next 13 months. Despite treatment with high-dose corticosteroids and cyclophosphamide, rapidly progressive glomerulonephritis developed, leading to chronic renal failure. There is convincing evidence of a link between the S. typhi infection and the ensuing catastrophic syndrome in this patient, probably precipitated by bacterial antigens.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
2/50. Defective fibrinogen polymerization associated with a novel gamma279Ala-->Asp mutation.A woman with menorrhagia was investigated for a suspected fibrinogen mutation when coagulation tests revealed prolonged thrombin (55 s) and reptilase (43 s) times together with a functional and an antigenic fibrinogen concentration of 0.7 and 2.8 mg/ml respectively. Heterozygosity for a gamma-chain mutation was suggested by a doublet gamma band on SDS-PAGE and an increased negative charge was observed on isoelectric focusing of HPLC-isolated gamma-chains. Electrospray ionization mass spectrometry revealed a gamma-chain mass of 48 411 Da, which was 20 Da more than the control value of 48 391 Da. Because the normal and variant gamma-chains were not resolved, this implied a 40-Da increase in 50% of the gamma-molecules. An increased negative charge and a 44-Da increase in mass was verified when dna sequencing showed heterozygosity for an Ala (GCC)-->Asp (GAC) substitution at codon 279 of the gamma-gene. Fibrin polymerization curves indicated a delay in the onset, and a decrease in the rate, of polymerization. Examination of crystal structures showed that the adjacent Tyr-gamma280 side chain is involved in bonding across the D-D interface, and from the proximity of the gamma279Ala-->Asp mutation it would appear that this perturbs the end-to-end DD interactions between fibrin units of the growing polymer.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
3/50. Acquired factor viii inhibitor associated with prostatic cancer: successful treatment with steroid and immunosuppressive therapy.factor viii inhibitors are antibodies of the IgG class that block functional epitopes or antigenic sites of factor viii. They occur in about 5-20% of hemophilia a patients after infusions of factor viii concentrate. antibodies to factor viii can also arise spontaneously in association with various autoimmune and chronic inflammatory diseases, hematologic malignancies, solid tumors, certain drugs, dermatologic conditions, and in puerperium. In the majority of cases, the clinical course is characterized by severe hemorrhages. Strategies to treat such inhibitors are controversial. We present the case of a patient with prostatic cancer who developed acquired factor viii inhibitor. His severe bleeding complications were treated successfully with cyclophosphamide in combination with methylprednisolone. Within a few months, moreover, the immunosuppressive therapy brought about complete disappearance of the inhibitor and normalization of coagulation parameters. Our case illustrates that, although the clinical course in patients with acquired factor viii inhibitor is not predictable, and the inhibitor may disappear spontaneously, combined therapy with cyclophosphamide and methylprednisolone should be considered for patients with severe hemorrhages.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
4/50. Gingival bleeding, epistaxis and haematoma three days after gastroenteritis: the haemorrhagic lupus anticoagulant syndrome.A 3 year and 9 month-old girl presented with gingival bleeding, epistaxis, and multiple haematomas 3 days after an acute episode of gastroenteritis. prothrombin time and activated partial thromboplastin time were prolonged with reduced clotting activity of factor II (< 10%), VIII (<1%), IX (3%), XII (10%) and evidence of a high titre inhibitor. Prothrombin (factor II) level was below the detection limit, both in a functional and immunological assay. It did not increase after administration of vitamin k or fresh frozen plasma. Further studies revealed presence of a strong lupus anticoagulant and a specific IgG antibody against prothrombin. factor viii antigen levels also were reduced (31%), but to a lesser extent than functionally determined factor viii (<1%). blood coagulation normalised following clinical recovery 6 weeks after admission. The pathophysiology of this acquired inhibitor phenomenon (accelerated clearance of complexes of clotting factors and phospholipids) is discussed. CONCLUSION: The haemorrhagic lupus anticoagulant syndrome (acquired hypoprothrombinaemia lupus anticoagulant syndrome) is a rare presentation of acquired bleeding diathesis in childhood. Since most cases in post-infectious children are asymptomatic, it might be underdiagnosed. In children with newly appearing bleeding symptoms or unclear prolonged prothrombin time or activated partial thromboplastin time, one has to consider this syndrome which could lead to relevant bleeding.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
5/50. Williams trait. Human kininogen deficiency with diminished levels of plasminogen proactivator and prekallikrein associated with abnormalities of the Hageman factor-dependent pathways.An asymptomatic woman (Ms. Williams) was found to have a severe abnormality in the surface-activated intrinsic coagulation, fibrinolytic, and kinin-generating pathways. Assays for known coagulation factors were nromal while Fletcher factor (pre-kallikrein) was 45%, insufficient to account for the observed markedly prolonged partial thromboplastin time. plasminogen proactivator was present at 20% of normal levels and addition of highly purified plasminogen proactivator containing 10% plasminogen activator partially corrected the coagulation and fibrinolytic abnormalities but not the kinin-generating defect. This effect was due to its plasminogen activator content. In addition, Williams trait plasma failed to convert prekallilrein to lakkilrein or release kinin upon incubation with kaolin. Kininogen antigen was undetectable. When normal plasma was fractionated to identify the factor that corrects all the abnormalities in Williams trait plasma, the Williams factor was identified as a form of kininogen by its behavior on ion exchange chromatography, gel filtration, disc gel electrophoresis, and elution from an anti-low molecular weight kininogen immunoadsorbent. High molecular weight kininogen as well as a subfraction of low molecular weight kininogen, possessed this corrective activity while the bulk of low molecular weight kininogen functioned only as a kallikrein substrate. Kininogen therefore is a critical factor required for the functioning of Hageman factor-dependent coagulation and fibrinolysis and for the activation of prekallikrein.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
6/50. prekallikrein deficiency: the characteristic normalization of the severely prolonged aPTT following increased preincubation time is due to autoactivation of factor xii.Hereditary plasma prekallikrein (PK) deficiency was diagnosed in a 71-year-old man with an 8-year history of osteomyelofibrosis. PK deficiency was suspected in view of a severely prolonged activated partial thromboplastin time (aPTT) that nearly normalized following prolonged preincubation (10 min) of patient plasma with kaolin-inosithin reagent. Hereditary PK deficiency was demonstrated by very low PK values in the propositus (PK clotting activity 5%, PK amidolytic activity 5%, PK antigen 2% of normal plasma, respectively) and half normal PK values in his children.Normalization of a severely increased aPTT (>120 s) after prolonged preincubation with aPTT reagent occurred in plasma deficient in PK but not in plasma deficient in factor xii (FXII), high-molecular-weight kininogen (HK), factor XI (FXI), factor ix, factor viii, Passovoy trait plasma or plasma containing lupus anticoagulant. Autoactivation of FXII in PK-deficient plasma in the presence of kaolin paralleled the normalization of aPTT. Addition of OT-2, a monoclonal antibody inhibiting activated FXII, prevented the normalization of aPTT. We conclude that the normalization of a severely prolonged aPTT upon increased preincubation time (PIT), characteristic of PK deficiency, is due to FXII autoactivation.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
7/50. Identification of simultaneous mutation of fibrinogen alpha chain and protein C genes in a Japanese kindred.Afibrinogenaemia usually induces a bleeding tendency during infancy, whereas protein c deficiency increases susceptibility to thrombosis in children or adolescence. Mutations of these genes have been, therefore, established as independent risk factors for coagulation disorders. We describe the homozygous mutation of the fibrinogen alpha chain gene and additional heterozygous mutation of the protein C gene in a male infant who showed prolonged umbilical bleeding after birth. On examination, the plasma fibrinogen was undetectable, and the activity and antigen level of protein C were reduced. The patient showed no fibrinogen Aalpha chain as well as Bbeta and gamma chains by Western blotting. The sequencing analysis showed the homozygous deletion of 1238 bases from intron 3 at position 2008 to intron 4 at position 3245 in the fibrinogen alpha chain gene. Both parents were heterozygous carriers of this mutation. In this patient, an additional mutation was also detected in the protein C gene: the heterozygous deletion of exon 7 at position 6161-6163 or 6164-6166, resulting the deletion of one amino acid (Lys150 or 151). His mother was also a carrier of this mutation. As the simultaneous mutation of the fibrinogen alpha chain and protein C genes has not been previously reported, the influence of the interaction between these two mutations on the clinical manifestations of this patient should be carefully monitored for a long period.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
8/50. Late-onset homozygous protein c deficiency manifesting cerebral infarction as the first symptom at age 27.We report a 31-year-old female who had repeated thrombosis and was diagnosed as having congenital homozygous protein c deficiency based on decreased protein C antigen and activity, and the findings of family history. This patient had shown no symptom of thrombosis until the age of 27 years, when she had cerebral infarction as the first symptom. Low molecular weight heparin was useful for disseminated intravascular coagulation (DIC) that complicated protein c deficiency in this patient.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
9/50. Protein C survival during replacement therapy in homozygous protein c deficiency.Homozygous protein C (PC) deficiency is a rare genetic defect that usually results in fatal thrombotic complications (purpura fulminans and DIC), but it can be successfully managed with oral anticoagulants or PC replacement. The successful use of PC replacement for two individuals is described. The activity and antigen levels of PC in fresh frozen plasma (FFP) and prothrombin complex concentrate (PCC) are also reported. The concentration of PC in FFP is 87 /- 15 units/dl. PC is present in all PCC analyzed; however, a ten-fold difference between the various brands and/or lots is noted. The PC activity and antigen correlates well with no significant levels of APC. Upon infusion of FFP into two homozygous PC-deficient children, the PC levels obtained were less than or equal to 30 units/dl post-infusion and undetectable after 12-18 hr. With infusions of PCC, plasma levels of PC obtained were 100-145 units/dl and less than 10 units/dl after 48 hr. The percent recovery and half-lives of PC from FFP and PCC were 49.8% and 7.8 hr, and 84% and 7.4 hr, respectively. One infant was treated every 48 hr for 2 years without significant purpura fulminans or DIC complications. The levels of the other PC system components did not change during the infusion of the PC-rich material. Based on this information, a specific replacement protocol has been developed using a PC-rich concentrate. However, several problems may arise with the "less pure" PC-rich concentrates: catheter-tip thrombosis, related large vessel thrombosis and blood-transmitted diseases. With a specific PC concentrate, replacement therapy is a viable alternative for the long-term management/treatment of homozygous PC deficiency.- - - - - - - - - - ranking = 2keywords = antigen (Clic here for more details about this article) |
10/50. Coexistence of congenital afibrinogenemia and protein c deficiency in a patient.A rare association of congenital afibrinogenemia and hereditary protein c deficiency is described in a 37-year-old female who suffered from ischemic necrosis in the left first toe. The diagnosis of afibrinogenemia was assessed by the absence of fibrinogen in clotting and immunological assays. The diagnosis of hereditary heterozygous type I protein c deficiency was based on the evidence of proportional decreases of activity and antigen of plasma protein C in the propositus, her mother, and two maternal aunts.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
| | Next -> |