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Pregnancy loss and thrombosis with protein C deficiency.

OBJECTIVES: Protein C inhibits coagulation and promotes fibrinolysis. This study investigates the association between protein C deficiency and pregnancy loss, thrombosis in pregnancy, and thrombosis with oral contraception. STUDY DESIGN: Fifteen protein C--deficient patients and 37 controls from a single kindred were studied. An obstetric history was obtained by telephone. Data were analyzed by logistic regression, Fisher's exact test, and Student t test. RESULTS: Protein C--deficient women experienced a 33% pregnancy loss versus 19% in the controls (not significant). Thromboembolism during pregnancy in protein C--deficient women was 33% (45% in those not receiving prophylactic anticoagulation) versus 5% in controls (odds ratio 7.37, p = 0.026). Five of 12 protein C--deficient women using oral contraception developed thrombosis versus 0 of 33 controls. The risk of thrombosis for protein C--deficient women using oral contraception is increased (p < 0.001). CONCLUSIONS: Perinatal outcome is not statistically different with protein C deficiency. Protein C deficiency increases the risk of thrombosis during pregnancy and with oral contraception. Prophylactic heparin is suggested during pregnancy for protein C--deficient women with personal or family histories of thrombosis. Oral contraception is not advised.

Adult↗

Heterozygous protein C deficiency type I.

Protein C is a vitamin K-dependent plasma protein which has anticoagulatory and profibrinolytic properties as a result of inactivating coagulation factors Va and VIIIa and enhancing fibrinolysis. Heterozygous protein C deficiency is well known to be a risk factor for thromboembolic diseases. We here present a family with 16 members deficient in protein C, out of which only two persons were suffering from thromboembolic disorders. In patients suffering from heterozygous protein C deficiency thromboembolic complications in childhood are rare and are not obligatory in adults. These patients should therefore not be treated with oral anticoagulants unless thromboembolic complications have already occurred or are imminent. Coumarin anticoagulation implicates a serious risk of coumarin skin necrosis in protein C deficient patients during the initial therapeutic phase. This risk may be avoided by initiating coumarin therapy with low doses of the drug and in cases of thromboembolic complications by overlapping with heparin anticoagulation.

Adolescent↗

Cardiopulmonary bypass for a coronary artery bypass graft patient with heterozygous protein C deficiency and protein S deficiency.

Cardiopulmonary bypass (CPB) poses great risks for hypercoagulable patients and requires management techniques to ensure an optimal outcome free from thrombotic events. This case report reviews perfusion management techniques that may contribute to a safer CPB experience for a patient deficient in both protein C and protein S. A patient with heterozygous protein C deficiency is at increased risk of thrombosis, especially in the venous circulation. Since it is an essential cofactor for activated protein C, deficiency of free protein S is also linked to a hypercoagulable condition. A 52-year-old male presented to our institution with a past medical history of hypercoagulable state, multiple deep vein thromboses, pulmonary embolisms, and stroke. He was scheduled for two-vessel coronary artery bypass graft surgery to be followed by right carotid endarterectomy (RCEA) before discharge. The anesthesia and perfusion teams worked closely together to ensure that fresh frozen plasma (FFP) was given intraoperatively at appropriate times. Heparin dose response and protamine dosage was determined with hemostasis management system (HMS) analysis. The closed CPB circuit and cannulae were Carmeda bonded. Rapid autologous priming, along with the use of a hemoconcentrator, kept the hematocrit above 21 during CPB. Zero-balance ultrafiltration and leukocyte depletion were initiated during rewarming to aid in attenuation of the inflammatory response. To conserve coagulation factors, all pump blood was ultrafiltrated post-CPB and returned to the patient. Laboratory samples drawn on postoperative day (POD) one measured normal protein C activity with subnormal protein S activity. On POD six, the patient underwent RCEA and he was discharged on POD eight without complications.

Cardiopulmonary Bypass↗

Accelerated brain infarction in hypertension complicated by hereditary heterozygous protein C deficiency.

BACKGROUND: Protein C deficiency leads to reduced inhibition of coagulation and an increased likelihood of thrombosis. It is widely accepted that the most common syndromes associated with protein C deficiency are venous thrombosis and pulmonary thromboembolism, whereas arterial thrombosis is rare. Here we describe two patients with hypertension and hereditary heterozygous protein C deficiency who developed multiple lacunar infarcts. CASE DESCRIPTIONS: Patient 1 was a 46-year-old man with a history of hypertension who developed a right upper quadrantanopia and gradually progressive intellectual and behavioral deterioration. Patient 2 was a 61-year-old man with history of hypertension and two episodes of right-sided motor weakness who developed left sixth and seventh cranial-nerve palsies and reduced pinprick sensation in the right extremities. In both patients, magnetic resonance imaging revealed multiple small lesions in the pons as well as the bilateral basal ganglia, thalamus, corona radiata, and other subcortical structures, which are consistent with lacunar infarcts. Protein C activity and antigen levels were reduced to approximately one half of normal in these two patients, as well as in some of their family members who had no other serological or coagulation abnormalities. A diagnosis of heterozygous protein C deficiency type 1 was thus established. CONCLUSIONS: Although it remains uncertain whether protein C deficiency itself increases the risk of cerebral artery thrombosis, it may predispose a patient to develop multiple brain infarctions in association with hypertension.

Blood Coagulation Disorders↗

[Perioperative management of a patient with purpura fulminans syndrome due to protein C deficiency].

PURPOSE: Protein C is a vitamin K-dependent anticoagulant and homozygous protein C deficiency is a rare fatal thrombotic disease. This report describes the perioperative management of homozygous protein C deficiency in a patient who underwent a total of three surgical procedures under general anesthesia and the successful use of activated protein C concentrate. CLINICAL FEATURES: A female baby, who developed disseminated intravascular coagulation and purpura fulminans shortly after birth, was diagnosed as purpura fulminans syndrome due to homozygous protein C deficiency. At one month of age, she suffered bilateral retinal detachment and glaucoma due to retinal hemorrhage. After marked improvement of her condition after administration of activated protein C concentrate, she underwent a left iridectomy and implantation of a Broviak catheter under general anesthesia. Her intraoperative course was uncomplicated but, on postoperative day four, she presented another episode of massive cutaneous necrosis and gangrene. Activated protein C concentrate was administered again, with good results. She underwent replacement of a Broviak catheter at four months of age, and right iridectomy for glaucoma at eight months. Both were uneventful. CONCLUSION: The perioperative management of homozygous protein C deficiency and purpura fulminans requires appropriate measures for thromboembolic prophylaxis. Sufficient iv fluid administration is necessary. Attention should be paid to decrease the risk of tissue compression such as that associated with positioning, blood pressure cuff, and endotracheal intubation, which may cause necrosis over pressure points. Replacement therapy with activated protein C concentrate appears safe and effective. The anesthetic management is reviewed and discussed.

Anesthesia, General↗

Identification of mutations in 15 Hungarian families with hereditary protein C deficiency.

Hereditary protein C deficiency represents about 2-9% of inherited thrombophilias. Our aim was to elucidate the molecular basis of protein C deficiency in 25 members of 15 Hungarian families with venous thromboembolic diseases and to identify hitherto undescribed genetical defects in the protein C (PROC) gene. The exons of the PROC gene were screened for mutations with the combination of polymerase chain reaction (PCR) and denaturing gradient gel electrophoresis (DGGE), and/or PCR and single-strand conformation polymorphism (SSCP) analysis. The amplified DNA fragments with aberrant migration during DGGE and SSCP were sequenced. Mutations were determined in the PROC gene in all of the examined families: one nonsense mutation, one rare frameshift deletion and nine different missense mutations, of which three were novel (1493 A-->G, 35Asp-->Gly; 6231 G-->A, 173Gly-->Glu; 8476 C-->T, 254Thr-->Ile). The combination of hereditary protein C deficiency with other hereditary thrombophilias was rather common. DGGE and SSCP were proved to be efficient and cost-effective screening methods in the genetic analysis of hereditary protein C deficiency.

Adult↗

Molecular genetic analysis of severe protein C deficiency.

Severe protein C deficiency is a rare, early onset, venous thrombotic condition that is inherited as an autosomal recessive trait. The protein C (PROC) genes of nine unrelated individuals with severe protein C deficiency were sequenced yielding a total of 13 different lesions. Eight of these were novel, including a gross gene deletion, three missense mutations, two micro-deletions, a splicing mutation and a single base-pair substitution in the HNF-3 binding site in the PROC gene promoter. Evidence for the pathogenicity of the mutations detected was obtained by molecular modelling, in vitro splicing assay and reporter gene assay. Neither the plasma protein C activity level nor the nature of the PROC gene lesions detected were found to be a good prognostic indicator of the age of onset or clinical severity of thrombotic symptoms. Other factors may thus complicate the relationship between genotype and clinical phenotype. Indeed, in two patients, the inheritance of either one or two Factor V Leiden alleles in addition to two PROC gene lesions could have served to precipitate the thrombotic events. No association was however apparent between clinical severity and the possession of a particular promoter polymorphism genotype. Despite the absence of a clear genotype-phenotype relationship, the molecular genetic analysis of the severe recessive form of protein C deficiency potentiates both the counselling of affected families and the provision of antenatal exclusion diagnosis.

Alternative Splicing↗

Bilateral retinal dysplasia and secondary glaucoma associated with homozygous protein C deficiency.

PURPOSE: Protein C deficiency is an autosomal recessive disorder, which predisposes the patient to potentially blinding and widespread lethal thromboembolic complications, especially in the homozygous type. We here report the first Korean case of ophthalmic involvement and its surgical treatment in homozygous protein C deficiency. METHODS: A 3.4kg, full term girl was born by normal delivery but showed bilateral leukocoria on day 2. Laboratory results disclosed a very low protein C activity level (10%) in the patient and moderately decreased levels in the other family members. Ophthalmic examination showed bilateral corneal opacity and shallow anterior chamber. B-scan ultrasonography which showed intravitreal mass lesions without microphthalmos and a funnel-shaped retinal detachment suggested bilateral retinal dysplasia. RESULTS: As the eyes were under progression of secondary glaucoma, bilateral lensectomies were performed at 2 months old and corneal opacity was regressed to some degree. However, at 14 months old, the left eye showed moderate corneal opacity with a band keratopathy. CONCLUSIONS: Although visual outcome was very poor after surgery, we could impede or slow down the progression of secondary glaucoma and save the eyeballs in the infant with homozygous protein C deficiency.

Anterior Chamber↗

Acute Budd-Chiari syndrome with hepatic failure and obstruction of the inferior vena cava as presenting manifestations of hereditary protein C deficiency.

The protein C system is essential in limiting the activation of coagulation in vivo. We report on a 29 year old woman with Budd-Chiari syndrome and occlusion of the inferior vena cava who presented with acute liver failure. She was successfully treated with an emergency mesoatrial shunt. Eight months after surgery, she has no ascites and normal liver function. She had a low concentration of plasma protein C on admission to hospital and during the follow up. Protein C deficiency subsequently was found in her father and two sisters, who were asymptomatic. Hereditary protein C deficiency should be considered in patients with Budd-Chiari syndrome.

Acute Disease↗

Ischemic stroke due to protein C deficiency.

Plasma protein C exerts anticoagulatory effects by inactivating factors V and VIII. Hereditary protein C deficiency is transmitted as an autosomal dominant disorder. Homozygous individuals usually develop purpura fulminans as newborns; heterozygous protein C-deficient individuals are at increased risk for venous thrombosis and pulmonary embolism. However, arterial thrombosis has been only rarely observed. We describe a young patient with heterozygous protein C deficiency who experienced a severe stroke due to thrombotic occlusion of the left middle cerebral artery.

Adult↗

Hereditary protein C deficiency.

Hereditary protein C deficiency, which is inherited as an autosomal-dominant trait, predisposes to venous thrombotic disease. Heterozygotes are at risk for superficial thrombophlebitis, deep venous thrombosis and/or pulmonary embolism, which may occur without apparent cause at a young age. Other manifestations are cerebral venous thrombosis and mesenteric vein thrombosis. In severe, often homozygous, protein C deficiency, a purpura fulminans syndrome may occur shortly after birth, resulting in death due to extensive thrombosis, if it is not adequately treated. The thrombotic manifestations in heterozygotes are effectively prevented by coumarin therapy. However, in the initial phase of oral anticoagulant therapy, the patients have an increased risk for the development of coumarin-induced haemorrhagic skin necrosis. The purpura fulminans syndrome can be treated with either replacement therapy or with coumarin therapy. Heparin appears to be ineffective in the prevention of both the purpura fulminans syndrome and the coumarin-induced skin necrosis.

Blood Coagulation Disorders↗

Identification of mutations in 90 of 121 consecutive symptomatic French patients with a type I protein C deficiency. The French INSERM Network on Molecular Abnormalities Responsible for Protein C and Protein S deficiencies.

By studying the protein C gene of 121 consecutive patients with symptomatic type I protein C deficiency, we detected 55 different candidate mutations in 90 cases. The mutations, 76% of which were missense changes, were distributed throughout the gene. More than half the missense mutations involved Cys, Phe, Pro, or Gly, amino acids known to affect the structure of the polypeptide chain by various mechanisms. Thus, 40% of protein C deficiencies may be caused by polypeptide chain instability rather than a lack of expression of the mutated allele; this may also account for phenotypic heterogeneity. Seventeen of the 55 different mutations were found in apparently unrelated families. Half the French families we studied bore one of these 17 mutations. The wide variety of mutations suggests that both sporadic cases and a founder effect contribute to the spectrum of protein C mutations in a given population. The differences in both unique and recurrent mutations in French and Dutch populations-the only large population samples so far studied-support this hypothesis.

Base Sequence↗

Diagnosis and treatment of homozygous protein C deficiency. Report of the Working Party on Homozygous Protein C Deficiency of the Subcommittee on Protein C and Protein S, International Committee on Thrombosis and Haemostasis.

This report summarizes the documented cases of homozygous protein C deficiency in the United States and Europe. Procedures for diagnosing and treating this disorder (both initially and over the long term) have been compiled by a working party on homozygous protein C deficiency of the Subcommittee on Protein C of the International Committee on Thrombosis and Haemostasis. Homozygous protein C deficiency is an autosomal recessive disorder that usually manifests itself by purpura fulminans and, less commonly, by massive large vein thrombosis; severe diffuse intravascular coagulation also develops in these infants, and there is evidence of intrauterine thrombosis. For confirmation of homozygous protein C deficiency in a neonate with purpura fulminans or massive venous thrombosis, the infant should have undetectable protein C activity and both parents should be heterozygous for protein C deficiency. At the onset of symptoms, the initial treatment should be plasma (8 to 12 ml/kg every 12 hours) until all lesions have healed. Two modalities for long-term treatment are accepted as useful in these children: oral anticoagulant therapy or protein C replacement (fresh frozen plasma or prothrombin complex concentrate). Liver transplantation has been performed in only one child, with success. Oral anticoagulation (vitamin K antagonists, maintaining the prothrombin time from one and one-half to two times control values or at the International Normalized Ratio of 2.5 to 4.4) is our recommendation of choice for long-term treatment. With appropriate care, these children are able to be free of coagulopathy and live relatively normal lives.

Anticoagulants↗

[Physiopathologic and clinical implications of protein C deficiencies].

The protein C system--a complex physiological coagulation inhibition system--is a major regulator which controls thrombin production. Nowadays, its exploration is indispensable for the detection of constitutional or acquired protein C deficiency, side by side with a search for antithrombin III deficiency. This approach, based on the frequent association of recurrent thrombosis, mainly venous, in young subjects with congenital deficiencies, makes it possible to initiate, beside a family survey, an individual and efficient prophylaxis of recurrent thrombosis.

Adult↗

Portal vein thrombosis with ruptured oesophageal varices as presenting manifestation of hereditary protein C deficiency.

The protein C system is essential in limiting the activation of coagulation in vivo. We report the case of a 45 year old man with portal vein thrombosis complicated by ruptured oesophageal varices. Low concentration of plasma protein C was found in the patient and subsequently in one brother with a history of venous thromboembolism, and also in one son and one nephew who were asymptomatic. Hereditary protein C deficiency should be considered in patients with portal hypertension due to portal vein thrombosis.

Esophageal and Gastric Varices↗