The pregnant antithrombin III deficient patient: management without antithrombin III concentrate.

Pregnant patients with antithrombin III (AT III) deficiency have an unacceptably high risk of venous thromboembolism (VTE). Antithrombotic therapy is therefore recommended. The reported clinical experience of such prophylaxis is limited. Some authors have recommended the use of AT III concentrate in addition to heparin in the management of these patients. We report successful management with heparin alone during pregnancy and the postpartum period in two patients with AT III deficiency. Both patients had experienced VTE during a prior pregnancy; one also experienced VTE during the reported pregnancy. Both patients were therefore at particularly high risk of further VTE. Based on the good results in these two patients, and a review of previously reported cases, we propose that heparin alone, in a dose to maintain the APTT in a therapeutic range, provides adequate prophylaxis and treatment for VTE during pregnancy and delivery in many AT III deficient subjects.     

Pasteurisation induced changes in an antithrombin III concentrate

The changes that take place when a therapeutic antithrombin III (AT III) concentrate is heated in the presence of citrate ion have been assessed. There is some loss of heparin cofactor antithrombin activity and of heparin binding ability. Protein aggregates are also formed during heating. These aggregates are not AT III but impurities in the concentrate.     

Antithrombin III microheterogeneity in antithrombin III deficiency and in the antithrombin III abnormality, "antithrombin III Toyama"

Antithrombin III (AT III) microheterogeneity was investigated in 12 cases of congenital AT III deficiency and 2 cases of congenital AT III abnormality by isoelectric focusing (IEF) and immunofixation. In congenital AT III deficiency, IEF and immunofixation revealed AT III as 8 bands which was indistinguishable from normal control in terms of the number of bands and the isoelectric point (pI) of each band. In the proband of the congenital AT III abnormality, however, IEF and immunofixation showed AT III as 8 bands which shifted slightly but definitely to the acidic side compared to those of normal subjects. This change in pI of the abnormal AT III was considered to reflect the amino acid replacement in the polypeptide chain of the abnormal AT III molecule.     

Klippel-Trenaunay syndrome associated with antithrombin III deficiency

Klippel-Trenaunay syndrome (KTS) is a rare phakomatosis characterized by cutaneous hemangiomata, venous varicosities and bone and soft tissue hypertrophy also of the affected limb. Central nervous system involvement is rare, arising from a malformation or from coagulation disorders. We report the case of a patient presenting a KTS with stroke. The biological assessment revealed antithrombin III deficiency. Although rare, antithrombin III deficiency should be kept in mind in KTS patients with neurological involvement.     

Properties and catabolism of heat treated antithrombin III concentrate

Heat treatment is employed to diminish the transmission of hepatitis when blood products are administered. It is possible that such a procedure could reduce the biological activity of the proteins and induce changes in structure and aggregation state. We have therefore made in vitro and pharmacokinetic studies of heat treated antithrombin III (AT III) concentrate using both radiolabelled and non-labelled preparations. The purification, heat treatment and the radiolabelling procedures did not induce any changes in the AT III molecules with exception of a decrease in heparin affinity in about 10% of the molecules. The studies using ¹²⁵I AT III showed that the fractional catabolic rate was increased and the half-life was shortened by about 20–25% compared to our previous studies on non-heat treated AT III concentrate. Our present findings indicating a mean half-life of 3.0 days are quite comparable to studies by others on non-heat treated AT III, however.     

Oxymetholone therapy in patients with familial antithrombin III deficiency

Three patients with familial antithrombin III (ATIII) deficiency, who also have histories of thromboembolism, were treated with oxymetholone in combination with warfarin. Thrombolysis was observed in one patient with acute thrombosis of inferior vena cava during the oxymetholone and warfarin therapy. No further thromboembolic episodes occurred in these patients after initiation of warfarin with or without oxymetholone. The levels of plasma ATIII, alpha 1-antitrypsin, plasminogen and Cl-inactivator were significantly increased in all patients after the introduction of oxymetholone therapy. This suggests that oxymetholone augments anticoagulant and fibinolytic activity. Hence we consider that oxymetholone in combination with warfarin may be possible thrombolytic therapy in patients with familial ATIII deficiency.     

Cerebral venous thrombosis with familial antithrombin III deficiency

A case of cerebral venous thrombosis with familial antithrombin III (AT III) deficiency was reported and we discussed the anticoagulant therapy of cerebral venous thrombosis from the viewpoint of AT III. The patient, a 17-year-old boy, was admitted to our clinic with severe bifrontal headache, generalized convulsions and progressive disturbance of consciousness. He developed deep vein thrombosis in his right leg and pulmonary emboli two years earlier when he was placed on heparin and so forth, followed by warfarin sodium. Warfarin was terminated 9 months prior to his recent illness. On neurological examination on admission, he was semicomatous with blurred disc margins, roving eye movements with right abducens nerve palsy, nuchal stiffness and right flaccid hemiplegia. Left carotid angiogram and CT scan revealed extensive superior sagittal sinus thrombosis, complicated with hemorrhagic infarcts in bilateral frontal lobes. When examined for coagulation studies, the patient and his father had decrease in AT III activity and antigen levels. He was treated successfully with antiedematous agents and anticonvulsants during acute phase of illness. He was thereafter placed on warfarin 5-6 mg/day with no further clinical thromboembolic event for 2 years 9 months. There was no neurological abnormality when he was last examined, although he was treated with valproic acid 1,200 mg/day and phenytoin 250 mg/day to control occasional adversive seizures. A coagulation study following infusion of 5,000 units of AT III was carried out. Warfarin was discontinued the day before the study. 0.64 U/kg of AT III administration resulted in a 1% increase in AT III level after the infusion. The biological half life of AT III was 14.4 hours.(ABSTRACT TRUNCATED AT 250 WORDS)     

Severe antithrombin III deficiency in an infant associated with multiple arterial and venous thromboses.

Inherited antithrombin III (AT-III, heparin cofactor) deficiency is a rare condition, presenting with thrombotic disease in adult life. This paper reports an 8 months old South African Black male infant with multiple large vessel venous and arterial thromboses, and E. coli septicaemia. This was associated with an extremely low plasma AT-III level. Micronodular cirrhosis and intracytoplasmic hyaline globules in the liver cells were present. These globules were eosinophilic, and PAS-positive after diastase. They measured approximately 5 mu to 30 muin diameter, occurred singly in the liver cells and were located mainly in the periportal areas. The histological findings in the liver are similar to those observed in alpha 1-antitrypsin (AAT) deficiency in which the intracytoplasmic globules represent accumulation of altered AAT. Immunochemical studies carried out on formalin fixed tissue failed to detect cross reaction material with anti-alpha 1 antitrypsin or anti-AT III antiserum. This is the first case report of AT-III deficiency presenting in infancy. It is also the first case associated with distinctive liver pathology. The available data presented are insufficient to distinguish between an inborn defect and acquired caused of the severely depressed AT-III plasma level and the distinctive liver pathology.     

Premature arterial disease associated with familial antithrombin III deficiency

Antithrombin III (ATIII) deficiency is one of the few known abnormalities of the coagulation system known to predispose to venous thromboembolism but its relation to arterial disease is not established. We describe two related patients with this disorder, both of whom suffered arterial thrombotic events, at an early age. Both patients had other potential risk factors, though these would normally be considered unlikely to lead to such catastrophic events at such an age. Thrombosis due to ATIII deficiency is potentially preventable, and this diagnosis should be sought more frequently in patients with arterial thromboembolism, particularly if occurring at a young age. In addition, in patients with known ATIII deficiency, other risk factors for arterial disease should be eliminated, if possible. In particular, these patients should be counselled against smoking.     

Elimination of intravenously administered radiolabelled antithrombin III and heparin in humans

Antithrombin III was purified from normal plasma by DEAE-Sephadex chromatography and heparin affinity chromatography; the protein was subsequently radiolabelled with 125I. 125I-antithrombin III alone and 125I-antithrombin III in the presence of high affinity 35S-heparin fractions were injected into normal humans. 125I-radiolabel and protein bound 35S-radioactivity were followed separately. In semilogarithmic plots 125I-antithrombin III disappeared according to a double exponential curve with a half-life in the second phase of 56.8 hr in the absence of heparin and of 33.7 hr in the presence of heparin. Protein bound 35S-radioactivity disappeared much faster than the 125I-radiolabel. These data support the concept that heparin disappears as free heparin from the equilibrium heparin - antithrombin III in equilibrium heparin + antithrombin III. Immuno-reactive antithrombin III decreased from 100% to 85-90% immediately after injection of 125I-antithrombin III in the presence of heparin and returned to normal values within 30 min. This suggests that antithrombin III is transiently sequestered, possibly in trimolecular complexes consisting of antithrombin III, heparin and either lipases or other vascular bound proteins.     

Familial antithrombin III deficiency in a Japanese family

Familial antithrombin III (AT III) deficiency was found in Japanese family. The propositus (38 yr old female) had history of venous thrombosis of the left lower leg at 29 yr old, thrombotic varicophlebitis of the left lower leg at 33 yr old, and mesenteric venous thrombosis at 34 yr old. Laboratory examinations were in normal range except hyperaggregability of platelets and AT III, which was depressed in both immunological and biological measurement. This is the first case where AT III deficiency and hyperaggregation of platelet in platelet-rich plasma level were observed. The immunological AT III concentration was also depressed in her mother, brother and son. However, their biological AT III activity did not parallel that of the immunological activity. This discrepancy is the reverse type of AT III “Budapest”.     

Safety of virus inactivated antithrombin III concentrate ANTITHROMBIN III IMMUNO (AT III)

In a prospective clinical trial the risk of infection after application of virus inactivated antithrombin III concentrate ANTITHROMBIN III IMMUNO (AT III) was investigated in patients undergoing cardiovascular surgery. The study was conducted according to the recommendations of the International Committee on Thrombosis and Hemostasis (ICTH), with the exception that most patients required additional blood products as well as AT III.

Twenty-seven patients were eligible to test for the risk of acquiring hepatitis B. Twenty-six patients could be evaluated in terms of hepatitis NANB transmission considering ALT-levels whereas 20 patients could be tested for anti-HCV one year after surgery. Samples from 78 patients could be monitored for anti-HIV-1. None of these patients showed any signs of infection. AT III IMMUNO seems to be an antithrombin III concentrate with low or absent infectivity.     

Thrombin generation and formation of thrombin-antithrombin III complexes in congenital antithrombin III deficiency

Two families with quantitative congenital AT III deficiency and a high incidence of thromboembolism are reported. In two unrelated patients (one from each family) thrombin generation in whole blood occured more rapidly than in the control, as demonstrated by the kinetics of prothrombin consumption, AT III disappearance and thrombin-antithrombin III complexes formation. Similar results were obtained in plasma and can be experimentally reproduced with a plasma depleted of AT III by immunoadsorption using a rabbit anti-AT III antiserum. The addition of purified AT III in vitro leads to a complete correction of the abnormalities when the level of AT III is greater than 0.8 unit/ml.