The effect of liver disease on factors V, VIII and protein C

The components of the factor VIII complex were estimated by immuno- and bioassays in 85 patients with liver disease. The plasma concentrations of the antigens were elevated in 65% (VIII:CAg) and in 76% (VIIIR:Ag) of patients while the biological activities were elevated in only 14% (VIII:C) and 15% (VIII:RiCof). There was no correlation with C-reactive protein, used as a measure of an acute phase reaction (X2 = 0.7; P = 0.1); or with severity of liver disease as judged by prothrombin ratio (P = 1.0) but highest values were observed in patients with cholestatic liver disease. Following parenteral vitamin K there was a significant fall in both the biological activity of VIIIC (36%) and of VIII:CAg (38%) in 13 vitamin K deficient patients (P less than 0.001) but no change in 23 vitamin K replete patients or in the VIIIR:Ag levels in either group. Factor V levels were lower in patients with parenchymal liver disease (0.54 +/- 0.1 units/ml, mean +/- SEM, n = 12; normal range 0.5-1.5 units/ml) than in patients with extrahepatic cholestasis who were vitamin K deficient (1.2 +/- 0.1 units/ml, P less than 0.0001). The levels of protein C antigen, the vitamin K dependent protease which inactivates factors VIII:C and V, was at the lower end of the range in both groups (0.7 +/- 0.1, mean +/- SEM, n = 18, normal range 0.74-1.4 units/ml). There was no significant change in either protein C antigen or factor V following vitamin K. The discrepancy between the biological activity of factor VIII and the antigen levels could represent accumulation of partially degraded factor VIII or production of a hypoactive form. There is no evidence that the reduction in VIIIC and VIII:CAg following vitamin K was mediated by protein C.     

Echis time,under‐carboxylated prothrombin and vitamin K status in intensive care patients

Vitamin K deficiency is a known cause of coagulopathy in hospitalized patients, but the extent of the problem has not been well assessed. This noninterventional, prospective observational study of 35 adults was undertaken in the intensive care unit (ICU) and examined the incidence of and the methods for diagnosing vitamin K deficiency. Measurements of prothrombin time, Echis time and plasma concentrations of under‐carboxylated prothrombin (proteins induced in vitamin K absence or antagonism, PIVKA‐II), vitamin K₁ and ferritin were made during the 48 h after admission to the unit and repeated if coagulopathy developed later. Plasma vitamin K₁ was low in 15 admissions (43%), in 11 cases of patients with coagulopathy and in four cases without coagulopathy. PIVKA‐II was present in 12 cases (34%), of whom four had low vitamin K₁ levels. All of the eight patients with raised PIVKA‐II but normal vitamin K concentration were hyperferritinaemic. We conclude that low plasma vitamin K levels, suggestive of low tissue stores, are common in intensive care patients with or without coagulopathy. As 34% of patients had a raised PIVKA‐II, this suggests that vitamin K stores may be insufficient to maintain full γ‐carboxylation of prothrombin and emphasize the need to anticipate vitamin K deficiency in the ICU setting by appropriate supplementation.     

Combined factor V/VIII deficiency: a case report including levels of factor V and factor VIII coagulant and antigen as well as protein C inhibitor

Comprehensive coagulation studies were performed on members of a family with combined factor V/VIII deficiency. The purpose of these studies was to investigate the hypothesis that combined factor V/VIII deficiency is due to a lack of the inhibitor to activated protein C. The analyses performed included routine APTT and PT, factor V and VIII coagulant activity and antigen levels, von Willebrand factor levels, protein C antigen assay, and both protein C inhibitor activity and antigen levels. Three of the 19 family members studied were found to have a deficiency of both factors V and VIII. These three individuals showed prolonged APTTs and PTs and decreased levels of factor V and factor VIII coagulant activity and antigen. Factor VIII related antigen and ristocetin cofactor (von Willebrand factor) levels were normal. Protein C and both protein C inhibitor activity and antigen levels were also found to be normal. These findings confirm the results of other recent investigators and indicate that the autosomal, inherited combined factor V/VIII deficiency is not due to a protein C inhibitor deficiency. The real defect in this combined deficiency remains to be determined.     

Vitamin K deficiency and D-dimer levels in the intensive care unit: a prospective cohort study.

Patients in the intensive care unit (ICU) are at risk for the development of vitamin K deficiency. We sought to determine the frequency of this deficiency by performing a prospective cohort study in which patients were screened for vitamin K deficiency on ICU admission and every other day thereafter. Vitamin K deficiency was diagnosed by a functional coagulation factor II to Echis factor II ratio < 0.70. Activity of the coagulation cascade was measured by D-dimer. In total, 40 patients were enrolled into the study. Seven of the patients had ratios < 0.70 on the day of admission to the ICU, and three patients developed ratios < 0.70. Thus, 10 of 40 patients (25%; 95% confidence interval, 12-38%) had vitamin K deficiency. Two patients developed coagulopathy, as indicated by an International Normalized Ratio of more than 1.4. D-dimer levels were elevated in 86 of 111 samples. We conclude that vitamin K deficiency is common among critically ill patients, particularly on admission to the ICU. Our findings suggest that additional clinical research is warranted to determine whether vitamin K supplementation on admission to the ICU reduces the risk of ICU-acquired vitamin K deficiency and its attendant complications over the course of the ICU stay.     

Echis time, under-carboxylated prothrombin and vitamin K status in intensive care patients

Vitamin K deficiency is a known cause of coagulopathy in hospitalized patients, but the extent of the problem has not been well assessed. This noninterventional, prospective observational study of 35 adults was undertaken in the intensive care unit (ICU) and examined the incidence of and the methods for diagnosing vitamin K deficiency. Measurements of prothrombin time, Echis time and plasma concentrations of under-carboxylated prothrombin (proteins induced in vitamin K absence or antagonism, PIVKA-II), vitamin K1 and ferritin were made during the 48 h after admission to the unit and repeated if coagulopathy developed later. Plasma vitamin K1 was low in 15 admissions (43%), in 11 cases of patients with coagulopathy and in four cases without coagulopathy. PIVKA-II was present in 12 cases (34%), of whom four had low vitamin K1 levels. All of the eight patients with raised PIVKA-II but normal vitamin K concentration were hyperferritinaemic. We conclude that low plasma vitamin K levels, suggestive of low tissue stores, are common in intensive care patients with or without coagulopathy. As 34% of patients had a raised PIVKA-II, this suggests that vitamin K stores may be insufficient to maintain full gamma-carboxylation of prothrombin and emphasize the need to anticipate vitamin K deficiency in the ICU setting by appropriate supplementation.     

Management of cesarean section under replacement therapy with factor VIII concentrates in a pregnant case with congenital combined deficiency of factor V and factor VIII

The congenital combined deficiency of Factor V and Factor VIII, a rare bleeding disorder, was identified in a 25-year-old woman. She was admitted to our hospital with a complaint of genital bleeding. Her prothrombin time and activated partial thromboplastin time were prolonged. She had low levels of Factor V coagulant activity (F. V:C) 14%, and Factor VIII coagulant activity (F. VIII:C), 12%, and normal levels of von Willebrand factor antigen (vWF:Ag), ristocetin cofactor (Rcof) and Protein C antigen. Her Protein C inhibitor level was slightly low. Her Rcof, vWF:Ag and F. VIII:C were elevated following administration of 1-deamino-8-D-arginine-vasopressin (DDAVP), but her F. V:C remained unchanged. Four years later, her F. VIII:C rose to 70% during the course of her pregnancy, but her F. V:C value remained low. It was expected that the vaginal delivery would be possible at the termination of pregnancy. Premature rupture of the membranes and an anomaly of rotation appeared in the course of delivery, however, and cesarean section was accomplished without excess bleeding under replacement therapy with Factor VIII concentrates. These findings suggested that DDAVP and Factor VIII concentrates were useful for management of her delivery. However the mechanisms of the rise of plasma F. VIII:C during pregnancy in a case with congenital combined deficiency of Factor V and Factor VIII are unclear.     

DDAVP administration in a case of congenital combined factor V and factor VIII deficiency

Combined deficiency of factor V and factor VIII, a rare bleeding disorder, was found in a 43 year-old male. He had often presented manifestations of easy bruising since childhood, but none of his family had shown evidence of a bleeding tendency. We examined him and his family as far as we could and his abnormality of blood coagulation was apparent, but the members of his family were normal. The prothrombin time and activated partial thromboplastin time of this patient were prolonged, but his thrombin time was normal. Factor V and factor VIII coagulant activity were low, but von Willebrand factor antigen and activity (ristocetin cofactor activity) levels were normal. Protein C and Protein C inhibitor antigen and activity levels were also found to be normal. Following 1-deamino-8-D-arginine vasopressin (DDAVP) injection, he had immediate increases in factor VIII coagulant activity, but both von Willebrand factor antigen, activity levels and factor V coagulant activity remained low. Moreover, there was no rapid decline in factor VIII complex activity. These findings suggest that the endogenous factor VIII in this patient is metabolized normally and that at least the deficiency of factor VIII does not result from accelerated degradation in plasma.     

Clotting changes in borderline hypertension

Coagulation factors evaluated in a group of patients with borderline hypertension. The following tests were carried out: prothrombin time (PT) and partial thromboplastin time (PTT), Factor VIII coagulant activity, Factor VIII antigen and Factor VIII ristocetin cofactor, Factor XII and Factor XI activities. These tests were selected for their relationship to the contact coagulative activation near the vascular wall. Comparing the results with those of normal controls, Factor VIII coagulant activity, Factor XII and PTT levels were significantly higher. Other tests were all within normal limits in both groups. High Factor VIII and Factor XII levels associated with PTT shortening suggest that an increased synthesis and/or release of these coagulation factors was present in our patients. Activated coagulation seems to be present in borderline hypertension before the appearance of clinical signs of vascular lesions.     

Radioimmunoassay of human prothrombin—The quantitation of plasma factor II antigen

Human factor II (prothrombin) was isolated by chromatographic techniques and showed a single band on electrophoresis. ¹²⁵I-tagged factor II was prepared by standard chloramine-T oxidation and sodium metabisulfite reduction. The radioimmunoassay (RIA) method used was a specific double-antibody radioimmunoassay similar to that described for the pituitary trophic hormones. The method showed high precision and sensitivity. A dose-response curve was generated by adding known amounts of normal human plasma to human barium sulfate-absorbed oxalated plasma. A straight-line relationship existed between 15 to 140% coagulant activity and 7 to 50 μg/ml antigen content. Plasma factor II antigen in 20 normals was 86.1 ± 8.4 μg/ml. Eight patients with induced vitamin K deficiency revealed normal antigen levels and reduced coagulant activity, whereas three patients with severe hepatocellular disease were found to have both antigen and coagulant activity reduced. Although coagulant activity decreased with prolonged storage, it was found that antigen content did not change with up to three months' storage at ? 20°C. The use of the RIA for measuring prothrombin protein in conjunction with coagulation factor assays may have clinical application in studying the mechanism of action of vitamin K, the developmental aspects of factor II production and activation, and the understanding of acquired coagulopathies.     

Superwarfarin intoxication: hematuria is a major clinical manifestation

Since superwarfarin is popular and readily available in stores, it may cause intoxication or overexposure, which can result in coagulopathy or abnormal bleeding in humans and, thus, is an important public health problem. We report our clinical experience with superwarfarin intoxication. Nine patients, including eight patients who had histories of ingesting superwarfarin, were studied. Of the patients, hematuria occurred in eight. Laboratory tests among the nine patients showed extremely prolonged prothrombin times and activated partial thromboplastin times, which could be corrected to normal by mixing 1:1 with normal pooled plasma; they also had very low functional levels of factor II, VII, IX, X, and proteins C and S, but normal functional levels of factors V, VIII, fibrinogen, and anti-thrombin III. Large doses of vitamin K1 were needed for 3 months or more to treat and correct the coagulopathy among the patients. The majority of the patients presented with gross hematuria, suggesting that hematuria is probably a major clinical manifestation of superwarfarin intoxication. Prolonged use of large doses of vitamin K1 is needed for the treatment of superwarfarin intoxication.     

ELEVATED von WILLEBRAND FACTOR ANTIGEN IN SYSTEMIC SCLEROSIS: RELATIONSHIP TO VISCERAL DISEASE

Plasma levels of the factor VIII complex (von Willebrand factorantigen, factor VIII coagulant and ristocetin co-factor) weremeasured in 28 patients with systemic sclerosis. Elevated vonWillebrand factor antigen was found in 12 patients overall andin 10 of 16 patients characterized by severe extensive visceraldisease, with a resulting positive correlation between the extentof visceral involvement and the plasma level of von Willebrandfactor antigen (r = 0.60, p < 0.001). Factor VIII coagulantand ristocetin co-factor levels, however, frequently failedto parallel the increases of von Willebrand factor antigen,supporting the view that these increases were due to in vivoendothelial damage. The findings suggest that vascular damageis an important aspect of the visceral lesions of systemic sclerosis. KEY WORDS: Systemic sclerosis, Endothelial disease, Factor VIII, Factor VIII multimers, C-reactive protein     

Combined factor V-VIII deficiency: a case report with studies of factor V and VIII activation by thrombin

A new case of combined factor V-VIII deficiency is reported with in vitro studies of factors V and VIII activation by thrombin. The normal activation of factors V and VIII demonstrated in the patient's plasma and the equivalent levels of factor VIII coagulant activity and coagulant antigen support the hypothesis that a quantitative rather than qualitative defect in factors V and VIII is present in this disorder.     

Orthotopic liver transplantation in a patient with combined hemophilia A and B

A 38-year-old man with severe factor IX and mild factor VIII deficiencies complicated by cirrhosis secondary to chronic non-A non-B hepatitis underwent orthotopic liver transplantation as treatment for both the cirrhosis and his congenital coagulopathy. Intraoperative hemostasis was obtained with factor VII-depleted prothrombin complex concentrate and fresh frozen plasma. Factor VIII and factor IX levels were assayed frequently in the perioperative period, and both returned to normal within 24 hr and remained normal postoperatively. Liver transplantation can be considered as definitive therapy for hemophilia A and/or B with transfusion-related liver disease.     

Secretion of functional plasma haemostasis proteins in long-term primary cultures of human hepatocytes

This study was designed to investigate the ability of long-term primary cultures of adult human hepatocytes to secrete the main haemostasis proteins. Factors II, V, VII, VIII, PIVKA-II (protein induced by vitamin K 1 absence or antagonist II), fibrinogen and antithrombin were quantified in culture medium by immunological methods and by measuring the coagulant activity of factors II, V and VII. All the haemostasis protein antigens except the factor VIII antigen (FVIII:Ag) were found in the culture medium throughout the culture period. The clotting activity of each factor correlated well with antigen level. In addition, fibrinogen and fibrin were detected in the fibrillar material following incubation of the culture medium with thromboplastin. Moreover, adding vitamin K 1 to the culture medium resulted in a significant increase of factors II and VII and a reciprocal decrease of the PIVKA-II, and adding von Willebrand factor resulted in a drastic increase of the level of FVIII:Ag. We conclude that, in our culture system, normal adult human hepatocytes retain their capacity to secrete haemostasis proteins for at least 30 days.     

Normal titer of functional and immunoreactive protein-C inhibitor in plasma of patients with congenital combined deficiency of factor V and factor VIII

Protein-C inhibitor (PCI) is a newly described plasma inhibitor directed against a vitamin-K-dependent serine protease, activated protein-C, which is involved in the inactivation of factor V and factor VIII. Marlar and Griffin have reported that PCI activity is absent in the plasma of patients with congenital combined factor V/VIII deficiency. We have measured the levels of PCI in the plasma of seven unrelated patients with this disorder using both functional and immunologic methods. The rate at which the amidolytic activity of activated protein-C was neutralized in the patients' plasma was essentially identical to that observed in normal plasma. The titer of PCI antigen, as measured by an electroimmunoassay using a monospecific anti-PCI serum, was 5.3 +/- 1.6 micrograms/ml in the patients' plasma and was not significantly different from that of normal plasma (5.3 +/- 2.7 micrograms/ml, n = 30). The levels of factor-V-related antigen, factor V coagulant antigen, and factor VIII coagulant antigen were low in all patient plasma and were in good agreement with their respective coagulant activity. Our results do not appear to support the hypothesis that combined factor V/VIII defect is due to a lack of PCI.     

Pharmacokinetics and efficacy of oral versus intravenous mixed-micellar phylloquinone (vitamin K1) in severe acute liver disease

BACKGROUND/AIMS: In patients with severe acute liver dysfunction, i.v. phylloquinone (vitamin K1) may be given to exclude vitamin K deficiency, rather than impaired hepatic synthesis of coagulation factors alone, as the cause of the coagulopathy. However, there have been no studies of the pharmacokinetics or efficacy of i.v. or oral K1 in such patients. METHODS: 49 adults with severe acute liver disease were randomised double-blind to a single 10 mg dose of i.v. or oral mixed-micellar K(1), or placebo. Serum levels of phylloquinone and undercarboxylated prothrombin (PIVKA-II) were assessed before and after treatment. RESULTS: At admission, 13 patients (27%) had either low serum K1 levels or elevated PIVKA-II concentrations, indicative of subclinical vitamin K deficiency. In the 16 patients who received i.v. K1, there was one (6%) treatment failure (K1 rise <10 ng/ml above baseline), compared with 12 of the 15 (80%) who received oral K1 (P<0.0001). One patient in the placebo group developed overt vitamin K deficiency. CONCLUSIONS: A minority of patients with severe acute liver dysfunction have subclinical vitamin K deficiency at the time of presentation, which is corrected by a single dose of i.v. K1. The intestinal absorption of mixed-micellar K1 is unreliable in adults with severe acute liver dysfunction.     

Factor V deficiency and its reversal with gluten restriction. In a patient with celiac disease

Hemorrhagic manifestations in patients with celiac disease are uncommon and, when present, are usually due to a deficiency of the vitamin K-dependent clotting factors. A patient with celiac disease was seen with a severe bleeding diathesis associated with deficiencies of factor V. The deficiencies of vitamin K-dependent clotting factors were rapidly reversed with parenteral administration of phytonadione. Factor V levels returned to normal levels only after gluten restriction.     

An Infant With Prolonged Circumcision Bleeding and Unexplained Coagulopathy

Tyrosinemia type I is a rare autosomal recessive disorder. Fulminant onset of liver failure can occur in the first few months of life. Because all of the clotting factors are produced exclusively in the liver except factor VIII, coagulation abnormalities are very common in patients with severe liver disease. Rarely a significant coagulopathy in the absence of overt signs of liver disease may be seen in hereditary tyrosinemia. We present a 4 weeks-old tyrosinemic infant who presented with severe bleeding after circumcision and no other signs of liver failure. The diagnosis of tyrosinemia should be kept in mind in differential diagnosis of bleeding disorders especially a severe coagulopathy unresponsive to vitamin K, and fresh frozen plasma, even when other signs of liver failure are absent.     

Spectrum of changes in endogenous thrombin potential due to heritable disorders of coagulation

The modern thrombin generation tests describe different phases of generation of thrombin that is initiation, amplification and inhibition of thrombin generation as well as the integral amount of generated thrombin. We investigated 55 patients with congenital deficiencies of different coagulation factors and analysed the relationship between the nature and the concentration of clotting factors, with different parameters of thrombin generation curve that is lag time, peak, time to peak and the area under curve or endogenous thrombin potential. The endogenous thrombin potential was unaffected by severe deficiency of factors XI and XII, and reduced in factor IX, VII and factor V and VIII deficiencies. The lag time was significantly prolonged in cases of severe factor VII, X and V deficiencies, and was almost normal in cases of factors VIII, IX, combined factors V and VIII, factor XI, XII and XIII deficiencies. The peak height was severely affected in cases of severe factor X, V, VIII and IX deficiency and combined deficiency of multiple vitamin K dependant coagulation factors, and significantly reduced in factor VIII, V, X, XIII and combined vitamin K deficiency.In all the patients with less than 40% thrombin generation, the clinical symptoms were severe. Bleeding symptoms were restricted to epistaxis and ecchymosis when thrombin generation was more than 90% of the normal. In the cases of combined deficiency of factors V and VIII all the values were intermediate as they exhibit mild deficiencies of both factors V and VIII and correlated well with the clinical symptoms. Endogenous thrombin potential of inherited isolated deficiencies of coagulation factors may thus provide an interesting insight about involvement of the deficient factor(s) at different phases of thrombin generation.     

Immunological Studies in Combined Factor V and Factor VIII Deficiency

Plasma samples from patients with inherited combined factor V and factor VIII deficiency were examined by immunological methods for the presence of factor V and Factor VIII-related antigens. A factor V-related antigen was consistently demonstrated in all plasma samples by inhibitor neutralization assay using a non-precipitating rabbit antibody. Factor VIII-related antigens were detected by inhibitor neutralization using human antibody and by electroimmunoassay using a precipitating rabbit antibody. The amounts of factor V and factor VIII-related antigens present in the patient's samples were similar to those found in normal human plasma. The findings confirm the presence of normal levels of factor VIII-related antigen in the plasma of these patients and suggest that inactive antigenic determinants of procoagulant factor V and procoagulant factor VIII are also present. The results are consistent with the possibility that a common precursor of porcoagulant factor V and factor VIII is defective in these patients.