Hereditary prothrombin deficiency

Hereditary prothrombin deficiency is one of the rare congenital coagulation defects. We report a case of 4 months old child who initially presented at 11/2 month of age with high-grade fever, generalized convulsions and brownish aspirate through nasogastric tube, diagnosed and managed as meningitis and sepsis. He was readmitted at 4 months of age with bruises over legs. Coagulation profile was suggestive of common pathway defect. Further evaluation revealed absent prothrombin level while other factors were within normal limits.

Congenital deficiencies and abnormalities of prothrombin

Prothrombin (factor II) deficiency was first described in 1947 by Quick et al., although the first prothrombin abnormality was reported in 1969 by Shapiro et al. The condition is still considered very rare. In spite of its rarity, the defect has allowed important improvements in our understanding of both congenital and acquired prothrombin deficiencies. The diagnosis of prothrombin deficiency or abnormality can be made using a combination of clotting, chromogenic and immunological assays. In cases of true deficiency, a parallel decrease in all these assays is observed, regardless of the activating agent. If discrepancies among the clotting assays are noted, particularly using viper venoms, a dysprothrombinemia should be suspected. Usually, activity levels less than 10% of normal are found in homozygotes, and between 40 and 60% in heterozygotes. Factor II levels in congenital dysprothrombinemias are more variable since one may encounter homozygotes, heterozygotes and compound heterozygotes between a heterozygous abnormality and heterozygous 'true' deficiency or between two distinct abnormalities. Usually the levels of factor II vary between 1 and 50% of normal. Antigen levels in congenital dysprothrombinemias will be normal, near normal or slightly decreased but always higher than the clotting counterpart. Cases with a parallel decrease in prothrombin activity and antigen should not be considered as examples of hypoprothrombinemia. The gene involved in the synthesis of prothrombin is located in chromosome 11. It is composed of 10 exons and 8 introns. Molecular biology studies have discovered several point mutations in some of the dysprothrombinemias. Bleeding manifestations may be severe in homozygous 'true' deficiency and may be more variable in dysprothrombinemias. Heterozygotes are usually asymptomatic. Prognosis is variable and generally in agreement with the prothrombin activity level. In homozygous true deficiency, hemarthroses and intracranial bleeding have been described. Substitution therapy is based on the administration of prothrombin complex concentrates or of plasma. The long half-life of prothrombin injected, about 70 h, allows the achievement of hemostatically effective levels (about 50% of normal) without difficulty.

Pregnancies in a patient with congenital absence of prothrombin activity: case report

Congenital hypoprothrombinemias are very rare, inherited disorders in which factor II (prothrombin) levels and/or activity are extremely low or absent. We report eight pregnancies in a patient with this disorder. Obstetric complications attributed to the coagulation disturbance included first-trimester bleeding in each pregnancy, miscarriage in four of the pregnancies, spontaneous maternal subarachnoid hemorrhage in one, and postpartum hemorrhage in one of four term pregnancies despite administration of clotting factor concentrate. The management of pregnancy in congenital hypoprothrombinemia, and issues of coagulation factor replacement, are discussed.

[Intracranial hemorrhage in congenital factor II deficiency]

A case of congenital defect of factor II is reported. It concerns a newborn with a not traumatic haematoma due to congenital hypoprothrombinaemia, which is rarely described in scientific literature.

Antenatally diagnosed subdural haemorrhage in congenital factor X deficiency

The presence of a subdural haemorrhage was observed in a fetus during antenatal ultrasound examination. The infant was found to be a homozygote for factor X deficiency. Prompt recognition permitted replacement treatment from an early stage. Inherited coagulation disorders should be suspected when intracranial haemorrhage is detected antenatally.

Prothrombin Segovia: a new congenital abnormality of prothrombin

A family with a new congenital dysprothrombinemia is presented. The propositus is a 21-yr-old man who presented simultaneously with hemartrosis of the left knee and an extensive hematoma following a minor trauma. Prothrombin time and activated partial thromboplastin time were prolonged. Prothrombin activity was very low when measured by biological assay using physiological activators (7% by one-stage method and 20% by two-stage method) or a Russel's viper venom-cephalin mixture (23%), Notechis scutatus scutatus venom (15%) and Echis carinatus venom (17%); in contrast, the level was found to be borderline to normal using Taipan viper venom (64%) and normal by both staphylocoagulase and immunologic methods. Family studies revealed consanguinity between the propositus' mother and father and both presented a 50% reduced prothrombin level when physiological activators or Echis carinatus viper venom were used. A line of identity between normal and abnormal prothrombin was observed on immunodiffusion. The migration of the abnormal prothrombin was less anodic and was not changed by the addition of calcium. The patient's serum showed 3 bands in the bidimensional immunoelectrophoresis system, whereas normal serum showed only 2 bands. The term prothrombin Segovia is proposed to define this new prothrombin abnormality.

Severe congenital factor X deficiency with intracranial haemorrhage

A Saudi Arabian infant with severe factor X deficiency who had had two intracranial haemorrhages is described. Attempts to raise his factor X level and improve his prothrombin time (PT) and partial thromboplastin time (PTT) by using vitamin K, oestradiol and danazol have failed. New therapeutic trials are necessary for patients with severe forms of this rare disorder.

Prothrombin Habana: a new dysfunctional molecule of human prothrombin associated with a true prothrombin deficiency

A Cuban family with a new congenital dysprothrombinaemia is described. The propositus was a 5-year-old female who presented with umbilical bleeding after birth followed by easy bruising and bleeding tendency throughout her life. The main laboratory features of the defect included prolongation of prothrombin time and partial thromboplastin time. Prothrombin activity was less than 10% in several one- and two-stage systems. However, the staphylocoagulase-complexed prothrombin level and immunologic methods yielded levels of about 50%. The migration of the abnormal prothrombin was more anodic in single and bidimensional immunoelectrophoresis system and did not change by the addition of calcium. Family studies revealed that the father had approximately 50% prothrombin activity and antigen, whereas the mother had 45% prothrombin activity but about 100% prothrombin antigen. We suggest that the propositus is heterozygous for an abnormal prothrombin and heterozygous for true prothrombin deficiency.

Prothrombin antigen evaluation by means of laser nephelometry in health and disease

Prothrombin antigen concentration was evaluated by means of laser nephelometry in 10 patients on coumarin therapy, in 17 patients with cirrhosis of the liver, and in four patients with congenital hypo- or dysprothrombinemias. The average values obtained were 46.4, 37.7, and 35.6%, respectively, for anticoagulated, cirrhotic, and congenitally abnormal patients. These values correlated well with those obtained by means of electroimmunoassay (Laurell) and immunodiffusion (Mancini) methods. Similarly, satisfactory results were obtained in eight normal subjects. Multiple evaluations at different incubation times, also allowed the authors to construct kinetic curves of the interaction between antigen and antibody. However, an abnormal kinetic curve was demonstrated only for coumarin-treated patients.

Prothrombin Gainesville. A dysprothrombinemia in a pair of identical twins

A pair of identical twins was evaluated for menometrorrhagia and mild post-operative bleeding. Each had a slightly prolonged partial thromboplastin time and prothrombin time. Full hemostatic evaluation was normal, except that plasma prothrombin activity was 23% and 25% of normal with a Russell's viper venom assay. Each twin had 70% of normal plasma prothrombin antigen. Prothrombin kinetic data were obtained before and during hysterectomy. In these twins, infused prothrombin (Konyne) was found to have a volume of distribution of approximately one and one-half times the plasma volume and a half-life of 34 hours. The previously reported dysprothrombins are briefly reviewed. Prothrombin Gainesville is the twelfth such disorder reported.

Congenital factor X deficiency in Japan

Congenital factor X deficiency is a very rare inherited coagulation abnormality. There have been reported 43 cases of this disorder in the world and only 2 cases in Japan. Recently, we have hemostatically and immunologically examined as many as 3 cases of this rare disease, 18-year-old male, 11-year-old male and 6-year-old female. Hemostatic examinations revealed prolonged prothrombin time, partial thromboplastin time and decreased serum thromboplastic activity in these 3 cases. Stypven-cephalin clotting time was also abnormal. Factor X activities of our cases were low when assayed by either tissue thromboplastin and partial thromboplastin or by Stypven-cephalin mixture, which were 2.6, 1.5 and 4.5%, respectively. The half lives of infused factor X were 24, 38.6 and 56 hr, respectively, which are consistent with the data of other authors. Immunological assay of factor X (radioimmunoassay) showed 0.47 microgram/ml in the second case and 0.15 microgram/ml in the third case, from which our cases were considered to be classical factor X deficiency.

Chromogenic substrate (S-2238) prothrombin assay in prothrombin deficiencies and abnormalities. Lack of identity with clotting assays in congenital dysprothrombinemias

Prothrombin was assayed using chromogenic substrate of S-2238 for patients who were being treated with coumarin, for patients who had liver disease, and for patients who had congenital hypoprothrombinemias and dysprothrombinemias. In coumarin therapy and in patients with liver disease the levels found correlated well with the one-stage clotting methods. The same was true for heterozygous and homozygous "true" prothrombin deficiency. In the case of congenital dysprothrombinemias the levels observed with the chromogenic substrate were higher than the clotting counterparts, particularly so in the case of prothrombin Padua. In the latter case the levels observed were always about 100% of normal, as compared with the levels of about 50% of normal found with clotting methods. These data indicate that chromogenic substrates are not always equivalent to "clotting" substrates, namely, that amidolytic activity is not always equivalent to clotting activity. Therefore the two methods cannot be used interchangeably, lest some defects escape detection.

Characterization of a variant prothrombin in a patient congenitally deficient in factors II, VII, IX and X

An 18-month-old child, who had no evidence of liver disease, malabsorption, or chronic ingestion of coumarin compounds, was found to have plasma deficiencies of factors II, VII, IX and X. Assays for factor II and X by immunological techniques (antibody neutralization and immunoelectrophoresis) revealed normal or elevated antigenic activity of these factors, suggesting the presence of abnormal protein variants in the patient's plasma. On two-dimensional immunoelectrophoresis of the patient's plasma in calcium, a normal and an abnormal population of prothrombin were seen. The abnormal prothrombin had a mobility more anodal than that of normal prothrombin, but less anodal than that of acarboxyprothrombin. The abnormal prothrombin, in contrast to acarboxyprothrombin, adsorbed readily to both aluminum hydroxide and barium citrate, and could be identified by two-dimensional immunoelectrophoresis of a barium citrate eluate. We suspect that the abnormal variant represents a partially carboxylated prothrombin.

Congenital deficiency of blood clotting factors II, VII, IX, and X

A patient congenitally deficient in factors II, VII, IX, and X has been further investigated after a follow-up of 15 yr. At birth, these factors, when determined by clotting assays, were undetectable. Following therapy with vitamin K1, the clotting activity of these factors rose but never exceeded 18% of normal. Immunologic assays revealed much higher levels of these factors than did clotting assays, thus suggesting that the vitamin-K-dependent factors were present in abnormal forms. Two-dimensional crossed immunoelectrophoresis showed that at least two forms of prothrombin were present in the patient's plasma. One form was similar to normal prothrombin; the other had the same mobility as acarboxyprothrombin. In addition, the majority of this fast-migrating peak was not adsorbable onto insoluble barium salts. These observations suggested that some molecules of the patient's prothrombin lacked the normal complement of gamma-carboxyglutamic acid residues. This observation was confirmed by a specific assay for gamma-carboxyglutamate. Since malabsorption of vitamin K, warfarin intoxication, and hepatic dysfunction were excluded as causes of this patient's syndrome, this rare congenital abnormality could represent either a defective gamma-carboxylation mechanism within the hepatocyte or faulty vitamin K transport.

Surgery in patients with congenital disorders of blood coagulation

Surgical procedures on patients with congenital disorders of blood coagulation can be performed with a high degree of confidence and an acceptable incidence of complications. During the period 1960-1975, 42 patients with congenital disorders of blood coagulation underwent 94 operative procedures at the New York Hopital-Cornell Medical Center. The coagulation defect was diagnosed preoperatively, in nearly all patients. Careful hematologic management, including specific factor replacement, is essential. The importance of meticulous hemostasis at surgery and careful monitoring of blood coagulation in the postoperative period is strongly emphasized.