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Coagulation abnormalities in the carbohydrate-deficient glycoprotein syndrome: case report and review of the literature.

The carbohydrate-deficient glycoprotein syndromes are a group of recently described autosomal recessive, metabolic defects affecting multiple systems. The disorder is caused by inefficient posttranslational glycosylation of glycoproteins. Patients with the syndrome present early in life with psychomotor retardation, seizures, hypotonia, and stroke-like episodes. They also have dysmorphic features including almond-shaped eyes, constant squint, inverted nipples, and buttock fat pads. One of the features of the syndrome is coagulopathy, and we report here a patient who presented with a prolonged activated partial thromboplastin time, and was subsequently diagnosed with the carbohydrate-deficient glycoprotein syndrome. We also summarize the results of five previously published studies of the coagulation system in these patients. Most of the reported patients are deficient in factor XI, protein C, antithrombin III, and protein S. Other coagulation proteins are less frequently affected. Both bleeding and thrombosis have been observed, yet the cause of the stroke-like episodes remains speculative. The carbohydrate-deficient glycoprotein syndrome is an increasingly recognized multisystem disorder affecting hemostasis, and thus will involve clinical hematologists as part of a multidisciplinary team caring for patients with the syndrome.

Blood Coagulation Disorders↗

Cleavage of human high-molecular weight kininogen by purified kallikreins and upon contact activation of plasma.

To study the digestion pattern of human high-molecular weight (mol wt) kininogen (HMWK) in plasma during contact activation we have prepared monoclonal antibodies (MoAbs) to the light-chain (LC) and the heavy-chain moiety of HMWK. One MoAb from each set was purified, and neither MoAb inhibited the clotting activity of HMWK. In enzyme-linked immunosorbent assay and immunoblotting experiments neither antibody bound to kininogen-deficient plasma. Digestion of purified HMWK with plasma kallikrein yielded, on reduced sodium dodecyl sulfate gels, two LC forms, at 62 and 49 kd, respectively. Digestion of HMWK with tissue kallikrein (TK) yielded mainly the 62-kd form. In immunoblot analyses of these digests, the anti-LC MoAb detected products at 62 and 49 kd respectively. With plasma kallikrein, the 62-kd species slowly shifted to 49 kd, and with TK, the 62-kd species accumulated with time. Anti-LC MoAb was also used as a probe in immunoblotting experiments to study the digestion pattern of HMWK in whole plasma activated with kaolin or dextran sulfate. In activated normal pooled plasma (NHP) and factor XI-deficient plasma, native HMWK (mol wt, 115 kd) was cleaved within five to ten minutes, and two LC forms at 62 and 49 kd were detected. In kaolin-activated prekallikrein (PK)-deficient plasma, the disappearance of the 115-kd form was relatively slow, and only the 62-kd form of LC was seen. HMWK was not cleaved when factor XII-deficient plasma was incubated with kaolin. LC-dependent coagulant activity paralleled the presence of LC bands seen in the immunoblots, and lower-mol wt fragments of LC were not identified. These data indicate that in activated NHP two forms of LC of HMWK (62 and 49 kd) are formed sequentially. Further, the LC-dependent coagulant activity remains detectable long enough to suggest that proteolytic inactivation of LC is too slow to be an important control mechanism.

Antibodies, Monoclonal↗

[Thrombin activatable fibrinolysis inhibitor (TAFI) and its importance in the regulation of fibrinolysis].

Thrombin activatable fibrinolysis inhibitor (TAFI) also named procarboxypeptidase U (CPU), procarboxypeptidase R (CPR) and plasma procarboxypeptidase B (CPB) provides an important link between fibrinolysis and coagulation cascade. Activated TAFI (TAFIa) reduces a generation of plasmin because it cleaves off the carboxy-terminal lysine residues from partially degraded fibrin and thereby abrogates the fibrin cofactor function in the tPA-mediated catalysis of plasminogen to plasmin. TAFI is activated by thrombin-thrombomodulin complex. TAFI transformation to the activated TAFI (TAFIa) induced by thrombin supports the important role of coagulation cascade in regulation of fibrinolysis. This can be proved by a fact that the patients with a factor XI (FXI) deficiency are prone to bleeding from tissues with a high local fibrinolytic activity (urinary tract, nose, oral cavity, tonsils) that can be explained by a decreased thrombin-mediated TAFI activation. On the other hand the prothrombotic mutation of factor V (FV Leiden) associated with a resistance to activated protein C (APC-resistance) possess both mechanisms-an increased thrombin generation in coagulation cascade and a down regulation of fibrinolysis by a way of the thrombin-induced TAFI activation. For the future an inhibition of TAFI (e.g. by FXI inhibitors) offers the therapeutic possibilities to improve the decreased fibrinolysis and increase the efficiency of fibrinolytic therapy in thrombotic disorders. In bleeding disorders (hemophilia A, B) the drugs with a higher efficiency of TAFI for down regulation of an increased fibrinolysis could be used.

Blood Coagulation↗

Structural changes of plasma high molecular weight kininogen after in vitro activation and in sepsis.

High molecular weight kininogen (HMWK) is a multifunctional protein that is a parent molecule for bradykinin, a cofactor for coagulation, and an inhibitor of cysteine proteases. On immunoblot, nonreduced plasma HMWK is usually two bands at 140 kd and 120 kd; reduced plasma HMWK is a single band at 120 kd. In both concentration-dependent and time-dependent experiments kaolin-activated normal plasma HMWK becomes cleaved in an ordered sequence. When nonreduced, HMWK on immunoblot in kaolin-activated plasma changes in size from a 140 kd band through a 120 kd intermediate to result in a stable 100 kd protein. When reduced, HMWK on immunoblot in kaolin-activated plasma changes from a single 120 kd band through a 56 kd intermediate to result in a stable 46 kd protein. A similar sequence of cleavage of plasma HMWK occurs when the soluble activator dextran sulfate is used to stimulate the system. Cleavage of plasma HMWK after kaolin activation occurs similarly in factor XI-deficient plasma as in normal plasma but is decreased in prekallikrein-deficient plasma. Prolonged kaolin activation of prekallikrein-deficient plasma results in HMWK cleavage to bands below 120 kd. No band of plasma HMWK below 120 kd appears in prolonged kaolin-activated factor XII-deficient plasma. In some patients with sepsis, detectable cleavage of plasma HMWK to bands below 120 kd may not be seen, even though the patient has other evidence for contact system activation. In conclusion, these studies indicate that certain cleaved patterns of plasma HMWK on immunoblot indicate prior activation of the contact system. However, the absence of these cleaved forms of plasma HMWK in a single plasma does not exclude the occurrence of contact activation.

Bacterial Infections↗

Potentiation of the function of Hageman factor fragments by high molecular weight kininogen.

Patients lacking high molecular weight (HMW) kininogen have profound abnormalities of the Hageman factor-dependent pathways of coagulation, kinin formation, and fibrinolysis. The ability of HMW kininogen to potentiate the Hageman factor fragments (HFf) activation of prekallikrein and Factor XI in plasma was studied. HFf only partially converted Factor XI to XIa and prekallikrein to kallikrein in plasma deficient in HMW kininogen (Williams trait), while enhanced activation of Factor XI and prekallikrein by HFf resulted after reconstitution with HMW kininogen. In a system using highly purified components, HMW kininogen increased the initial rate of prekallikrein activation whether the kallikrein formed was assayed by arginine esterase activity or kininforming ability. The potentiation of prekallikrein activation occurred over a 12-fold range of enzyme (HFf) concentration and was nonhyperbolic with respect to substrate (prekallikrein). HMW kininogen exerted its effect even in the absence of prekallikrein since the hydrolysis of acetylglycyl-lysine methyl ester by HFf was increased by HMW kininogen. These results suggest that one of the functions of HMW kininogen is to augment the catalytic action of HFf.

Blood Coagulation Disorders↗

Coagulation-factor deficiencies and abnormal bleeding in Noonan's syndrome.

Noonan's syndrome is characterised by a dysmorphic facies, congenital heart disease, and short stature, and is inherited as an autosomal dominant trait. Because abnormal bleeding has also been reported, we investigated a group of patients for coagulation-factor deficits. Of the 72 individuals studied (37 male, 35 female, mean age 11.4 years), 47 (65%) had a history of abnormal bruising or bleeding. 29 patients (40%) had a prolonged activated partial thromboplastin time. Specific abnormalities in the intrinsic pathway of coagulation (partial factor XI:C, XII:C, and VIII:C deficiencies) were found in 36 patients (50%). Multiple abnormalities among these 36 patients included combined factor XI:C and XII:C deficiencies (4 patients) and factor XI:C and VIII:C deficiencies (4), and 1 patient had combined factor VIII:C, XI:C, and XII:C deficiency. There was poor correlation between a history of abnormal bleeding and coagulation-factor deficit. In five families, similar coagulation-factor deficiencies were present in first-degree relatives with the syndrome. The pattern of inherited bleeding abnormalities seen in Noonan's syndrome suggests autosomal regulation of the intrinsic coagulation pathway.

Adolescent↗

Women and inherited bleeding disorders: menstrual issues.

Von Willebrand, who described a bleeder family from Aland in 1926 in whom the index patient died at the fourth menses, stated, "the trait seems to be seen among women." Menorrhagia is defined objectively as a menstrual blood loss of at least 80 mL. However, even though 5% of women aged 30 to 49 years consult their general practitioner and 12% of gynecologic referrals are for menorrhagia, the diagnosis is difficult. A pictorial bleeding assessment chart (PBAC) has a specificity and sensitivity of more than 80%, with a score of > or = 100 being equivalent to more than 80 mL of blood loss. Using this chart to screen 150 women with menorrhagia who attended a gynecology clinic, an inherited bleeding disorder was diagnosed in 17%. Menorrhagia with onset at the menarche was predictive of an inherited bleeding disorder in 65% of von Willebrand's disease (vWD) and 67% of factor XI (FXI)-deficient patients. A retrospective survey in patients with inherited bleeding disorders using the PBAC showed menorrhagia in 74% of patients with vWD, 57% of carriers of hemophilia A or B, and 59% of FXI-deficient patients, compared with 29% of control individuals. Menorrhagia was the most common symptom in 60% of patients with FVII deficiency studied. Menorrhagia in women with bleeding disorders can be controlled with tranexamic acid with good effect. More recently, a desmopressin acetate (DDAVP) spray has been shown to achieve good FVIII and von Willebrand factor (vWF) levels and is efficacious for women with these deficiencies. The oral contraceptive pill may be useful. Since bleeding disorders are found in a substantial number of women with menorrhagia, it is important that such patients are investigated for these disorders before invasive procedures are done; hysteroscopy and hysterectomy in these patients are associated with a high rate of postoperative bleeding.

Family Health↗

The intrinsic pathway of coagulation is essential for thrombus stability in mice.

Blood coagulation is a highly regulated process involving interactions between platelets, plasma coagulation factors, and the vessel wall. During coagulation in vivo, fibrin formation is thought to be initiated when plasma factor VIIa forms a complex with the membrane protein tissue factor. Coagulation factor XII (FXII, Hageman factor) is required for some in vitro coagulation systems; however, FXII deficiency is not associated with hemorrhage, leading to the conclusion that it is not necessary for hemostasis. We generated FXII-deficient mice to study the contributions of FXII to thrombosis and hemostasis in arterial injury models and in models of acute arterial occlusion. FXII-deficient mice do not experience excessive injury-related bleeding; however, intravital fluorescence microscopy and blood flow measurements in three separate arterial beds revealed a severe defect in formation and stabilization of platelet-rich occlusive thrombi induced by different methods of injuries. Similar findings were observed for mice deficient in factor XI, a substrate of activated FXII. Infusion of human FXII into FXII null mice restored thrombus formation. These findings demonstrate that FXII-mediated fibrin formation is crucial for pathological arterial thrombosis but not for hemostasis and suggest that FXII could be an ideal target for safe anticoagulation.

Animals↗

Obstetrical and gynaecological bleeding: a common presenting symptom.

Excessive haemorrhage is one of the commonest symptom when women present to obstetricians and gynaecologists. In the majority of cases the cause is related to the primary obstetric and gynaecological pathology and is easily identified. However, less commonly, the bleeding is unexpected and due to an undiagnosed underlying coagulation defect, the commonest of which is von Willebrand (vWD) disease. Menorrhagia is a common, and may be the only, clinical manifestation of an inherited bleeding disorder. Screening 150 women with menorrhagia, vWD was diagnosed in 13% of patients and other hereditary haemorrhagic disorders in another 4%. Menorrhagia with onset at the menarche was predictive of an inherited bleeding disorder in 65% of vWD and 67% of FXI deficient patients. Therefore, testing for bleeding disorders should be considered in women with menorrhagia especially those with early onset and no obvious pelvic pathology. Childbirth and puerperium present a special risk for excessive haemorrhage. The risk of postpartum haemorrhage is very high in women with inherited bleeding disorders. In our centre, the incidence of primary and secondary postpartum haemorrhage was 22% and 11% in carriers of haemophilia 18.5% and 20% in vWD and 16% and 24% in FXI deficient women, respectively. Acquired haemophilia can be an unusual cause of severe and unexpected postpartum haemorrhage with a very high mortality rate. Unexplained postpartum and postoperative haemorrhage that does not respond to general measures should alert clinicians to the possibility of bleeding disorders as a causative factor. In addition, increased awareness among obstetricians and gynaecologists of these less common causes and close collaboration with the local haemophilia centre and availability of management guidelines are essential for optimal outcome.

Adult↗

Quality of life during menstruation in patients with inherited bleeding disorders.

Menorrhagia is a common and major problem for patients with inherited bleeding disorders, especially vWD. Quality of life during menstruation was assessed in 99 patients with inherited bleeding disorders including vWD (n = 57), carriers of haemophilia A (n = 17), carriers of haemophilia B (n = 7) and FXI deficiency (n = 18), and comparison was performed with an age-matched control group (n = 69). A questionnaire was used that included four main sections: (i) general health, (ii) health and daily activities, (iii) dysmenorrhea and (iv) quality of life during the menstrual period. Although patients with inherited bleeding disorders felt that their health (in general) was very good, they had significantly poorer quality of life on all the scales used than controls. Thirty-nine per cent reported having cut down on the amount of time spent on work and other activities as a result of their menstruation; 47% felt that they accomplished less than they would like during this period, 38% felt that they were limited in the kind of work and other activities that they could do, and 40% found that it took extra effort to perform their work. Fifty-one per cent experienced moderate, severe or very severe dysmenorrhoea. Quality of life was statistically poorer in patients with vWD, menstrual scores > 100 according to the pictorial blood assessment chart (PBAC), those who had periods > or = 8 days and those who experienced flooding or passage of clots. In conclusion, menstruation has a negative effect on the quality of life in patients with inherited bleeding disorders especially in those with objectively confirmed menorrhagia.

Adolescent↗

Inherited enzyme deficiencies in livestock.

The biochemical basis of over 300 inherited diseases has been defined in humans, and the majority involve abnormalities in enzymes. The rate of discovery of new defects is accelerating as biochemical and molecular technologies improve. The majority of inherited defects are expressed before puberty and approximately 25% are apparent at birth. Genomes of other mammals are similar and have been subjected to similar mutation pressures; therefore, it is probable that a range of inherited defects exists in livestock similar to that in humans. Because modern livestock populations have emerged from small population bases, the range of genetic aberrations, within breeds, will be less than in the general human population. Even if there is a 10-fold difference, however, there will be a bewildering array of defects possible in each breed. Because the level of inbreeding within livestock populations is greater than in the general human population, on the other hand, the prevalence of specific defects will be higher. It is probable that a high prevalence of a lethal recessive defect could occur within a particular livestock population and escape recognition. First, livestock producers accept a relatively high neonatal mortality rate without seeking a diagnosis. Second, few if any veterinary diagnostic facilities possess either the instrumentation or the analytic skills essential for investigating the vast range of potential inborn errors of metabolism. Third, national selection programs--e.g., those employed within the dairy industry--tend to use production data from adult progeny in selection. Consequently, the programs would not detect differences in fetal or neonatal mortality rates among descendants of specific sires until a deleterious defect had been widely disseminated.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

The effect of L-asparaginase of plasma coagulation factors in acute lymphoblastic leukemia.

Serial coagulation studies were performed in 26 pediatric patients with acute lymphoblastic leukemia during initial induction therapy with vincristine, prednisone, and L-asparaginase. Prolongation of screening coagulation tests was frequent: prothrombin time (in 16 of 26 patients), partial thromboplastin time (23/26) and thrombin time (21/26). In all 26 patients fibrinogen levels fell below .20 g/100 ml and 16 had levels below .10 g/100 ml. Sixteen patients had plasma coagulation factor assays performed. In these 16 patients, Factor XI was less than 40% in 14 and Factor XI was less than 70% in 9, with only a few scattered low levels of other factors. There were no clinical bleeding episodes. Coagulation abnormalities returned to normal at the completion of L-asparaginase therapy while the patients remained on vincristine and prednisone.

Afibrinogenemia↗

L-Asparaginase-induced coagulopathy during therapy of acute lymphocytic leukemia.

L-Asparaginase-induced coagulation abnormalities were observed in all patients receivng this drug. All patients studied demonstrated low factor IX and fibrinogen levels and most (75%) had low levels of factor XI. Disturbances in other factors were much less frequent. Despite the presence of markedly abnormal coagulation studies, clinical bleeding was not observed.

Adolescent↗

"Haemostasis time", a modified bleeding time test and its comparison with the Duke and Ivy/template bleeding times. II. Application in bleeding disorders.

"Haemostasis time" (HT), the occlusion time of a Butterfly 25 short cannula inserted into the cubital vein, is a bleeding time modification comparable to the skin bleeding times according to Duke and Ivy/Mielke. It also measures platelet function and is not influenced more than the latter tests by clotting factors. In HT, subendothelium is replaced by a standard artificial surface. The technique was investigated in patients with haemophilia A and B, von Willebrand's disease (vWD), and defects of factors VII and XI. HT was prolonged in 9/16 patients with haemophilia A/B, but did not correlate with the factor VIII:C/IX:C values. However, it reflected the different bleeding tendencies in those patients as represented by early or late onset of bleeding symptoms and occurrence of spontaneous haemarthroses. Of the vWD patients, not classified by multimeric analysis, 15/31 had prolonged Simplate II bleeding times, 14/31 prolonged HTs. Only 20/31 patients had corresponding normal or prolonged bleeding times with both techniques. HT correlated significantly with the Duke bleeding time (p = 0.011), ristocetin cofactor activity (p = 0.003) and von Willebrand factor antigen (p = 0.022), while no correlations were found between these parameters and the Simplate II method. Statistical evaluation shows, that in vWD, HT can replace the less precise Duke bleeding time but not the non-related Ivy/Simplate techniques.

Adolescent↗

[Fractures in hemophilia patients].

The authors give a review of the most frequent forms of hemophilia and describe the problems connected with fractures in patients suffering from hemophilia, the treatment methods and the indications for conservative or surgical therapy. The evaluation of 25 cases with hemophilia treated between 1972 and 1982 for one or more fractures shows that the primary disease does not essentially influence the healing process with the understanding that an early and sufficient substitution of the missing coagulation factors is administered. By means of a correct pretreatment (infusions of plasma or coagulation factors), we have obtained good results in most of our cases.

Adolescent↗