Frequency of protein S deficiency in general Japanese population

Thrombosis-related characteristics of pregnant women with antithrombin deficiency, protein C deficiency and protein S deficiency in Japan

BACKGROUND

 We previously conducted a primary survey of pregnant women with hereditary thrombophilia based on national surveillance in Japan, but did not examine their thrombosis-related characteristics. Antithrombin (AT) deficiency, protein C (PC) deficiency and protein S (PS) deficiency are the major types of hereditary thrombophilia in Japan.

METHODS

We examined their detailed information related to thrombosis, and evaluated peripartum outcomes in comparison with control data obtained from the Japan Society of Obstetrics and Gynecology.

RESULTS

Definite or probable AT deficiency, PC deficiency and PS deficiency were observed in 80, 50, and 317 pregnancies, respectively, from 2014 to 2018 in Japan, with prevalence rates among total deliveries of 0.011%, 0.007%, 0.044%. The number of pregnancies with AT, PC and PS deficiency might have been as many as 27, 17 and 108 every year if complete answers had been provided. In the peripartum period of current pregnancies, 27.5% of women with AT deficiency, 28.0% with PC deficiency and 13.2% with PS deficiency developed thrombosis (p < 0.001 vs. control). Pregnant women with AT and PC deficiency were more susceptible to thrombosis than those with PS deficiency (P < 0.01). Of the thromboses, 92.3% occurred during pregnancy, 62.8% at less than 15 gestational weeks. The earliest onset of thrombosis was 5 gestational weeks. Prophylactic anticoagulation significantly prevented the onset of both antepartum and postpartum thrombosis (p < 0.0001). The rate of recurrent pregnancy loss in women with low PC or PS activities was significantly higher than in controls (p < 0.0001); however, it is unknown whether recurrent pregnancy loss is related to hereditary PS deficiency. There seem to have been few serious maternal or fetal/neonatal complications due to placental insufficiency related to a hypercoagulable state other than growth restriction.

CONCLUSIONS

This survey revealed the thrombosis-related characteristics of pregnant women with hereditary thrombophilia in Japan. We suggest prophylactic anticoagulation to prevent maternal or fetal/neonatal complications.

Peripartum management of hereditary thrombophilia: results of primary surveillance in Japan

This study investigated patients with thrombophilia and current peripartum management practices based on national surveillance in Japan. Between 2014 and 2018, antithrombin (AT), protein C (PC) and protein S (PS) deficiency were observed in 84, 67, and 443 pregnancies, respectively, with incidence rates among total deliveries at 0.012%, 0.009%, and 0.061%. The percentage of institutions that measured both antigens and AT, PC, and PS activity for the diagnosis of thrombophilia was 50.2%, and 46.9% of institutions did not perform gene analysis. Prophylactic anticoagulation therapy was used in the ante- and postpartum management of patients with AT deficiency at 67.1% and 66.3% of institutions, most commonly with 10,000 units of unfractionated heparin. Ante- and postpartum management of PC and PS deficiency was performed at 75.3% and 67.1% of institutions. Approximately half of the institutions performed peripartum prophylactic AT supplementation for AT deficiency. Low trough AT activity before supplementation was most commonly 50 ≤  < 70%, and the highest AT supplementation was 1500 ≤  < 3000 units. The number of pregnancies with AT, PC and PS deficiency might be as many as 29, 23 and 151 every year in Japan if complete answers were provided.

Clinical guidance for peripartum management of patients with hereditary thrombophilia

Hereditary thrombophilia is a condition in which individuals are susceptible to the formation of thrombi due to a hereditary deficiency in anticoagulant factors, antithrombin (AT), protein C (PC), or protein S (PS). Many Japanese thrombophilia patients have PS deficiency, especially PS p.K196E (also called as PS Tokushima), which is exclusive to the Japanese population, and thrombosis sometimes occurs during pregnancy. At present, no management guidelines for pregnancy and delivery in thrombophilia patients have been developed. The Study Group for Hereditary Thrombophilia, one of the research groups of blood coagulation abnormalities in the Research Program on Rare and Intractable Diseases supported with the Research Grants of the Ministry of Health, Labour and Welfare Science, has therefore developed this clinical guidance to provide healthcare workers with necessary information on safe pregnancy, parturition and neonatal management, adopting a format of responses to seven clinical questions (CQ). At the end of each answer, the corresponding Recommendation Level (A, B, C) is indicated.

Incidence of venous thromboembolism in patients with solid cancers in Japan: retrospective study of 2735 patients

BACKGROUND

The incidence of cancer-associated venous thromboembolism (CA-VTE) in Japan has not been fully investigated.

METHODS AND RESULTS

Clinicopathological information from patients with solid malignancies who first visited our department between November 2011 and March 2018 were retrospectively reviewed from medical records. The primary outcome was incidence of CA-VTE, defined as deep-vein thrombosis (DVT) and/or pulmonary embolism (PE). On median follow-up of 187 days, 91 of 2735 patients (3.3%) developed CA-VTE during their clinical course, giving an incidence rate of 40.7 per 1000 person-years. Of the 91 patients, 75 (82%) were diagnosed with DVT alone, 6 (7%) with PE alone, and 10 (11%) with both DVT and PE. CA-VTE was most frequent in non-small cell lung cancer (10.8%), followed by cancer of unknown origin (5.8%). Forty-four patients (48%) had one or more symptoms at the initial diagnosis of VTE. Five patients (6%) had a normal D-dimer level (≤ 1.0 µg/mL); of these, 2 were asymptomatic.

CONCLUSIONS

In this retrospective study, the incidence of CA-VTE in Japanese patients with cancer was equivalent to that in Western populations. Approximately half of CA-VTE patients were asymptomatic and 6% had normal D-dimer levels, indicating the need for closer attention to occult CA-VTE.

Successful endovascular recanalization of massive cerebral venous sinus thrombosis in a patient with tuberous sclerosis and protein S deficiency: a case report

Here, we report the case of a 27-year-old woman with tuberous sclerosis complex who underwent successful endovascular intervention for cerebral venous thrombosis at the superior sagittal sinus. She had protein S deficiency and a long-term history of anemia caused by menorrhagia from uterine fibroids, possibly leading to a hypercoagulable state. Cerebral venous sinus thrombosis accounts for ~0.5–1% of all strokes. Several cases of venous thrombosis in patients with tuberous sclerosis complex and protein S or protein C deficiency have been reported, but further studies are needed to identify whether an association of this rare combination may be explained.

Stent thrombosis caused by metal allergy complicated by protein S deficiency and heparin-induced thrombocytopenia: a case report and review of the literature

A 43-year-old woman recipient of a bare metal coronary stent during an acute anterior myocardial infarction was repeatedly hospitalized with recurrent stent thrombosis (ST) over the following 3 years. Emergent coronary angiography showed a thrombus in the in-stent segment of the proximal left anterior descending artery. We repeatedly aspirated the thrombus, which immediately reformed multiple times. The discontinuation of heparin and administration of thrombolytics and argatroban, followed by repeated balloon dilatations, ended the formation of new thrombi. The patient was found to be allergic to nickel, protein S deficient and carrier of heparin-induced thrombocytopenia antibody. We discuss this case in the context of a) literature pertaining to acute coronary syndromes in the young, and b) the detailed investigations needed to identify thrombotic risk factors. Steroids may be effective to prevent recurrent ST caused by stent allergy.

Low levels of plasma protein S, protein C and coagulation factor XII during early pregnancy and adverse pregnancy outcome

It was the study objective to evaluate whether low levels of plasma protein S (PS) activity, free PS, protein C (PC) activity and coagulation factor XII (FXII) during early pregnancy are related to adverse pregnancy outcomes. Peripheral blood samples were obtained at 8-14 gestational weeks (GW) from a consecutive series of 1,220 women. The levels of plasma PS activity, free PS, PC activity, and FXII were measured. Cut-off values were defined as < 1st, < 5th, and < 10th percentiles of values obtained from 933 women whose pregnancies ended in normal deliveries without complications. PS activity of < 10th percentile yielded risks of pregnancy-induced hypertension (PIH) and severe PIH, while free PS level of < 5th percentile yielded a risk of pre-eclampsia. FXII level of < 1st percentile yielded a risk of premature delivery (PD) at < 34 GW. None was associated with PD at < 37 GW, fetal growth restriction or fetal loss. A multivariate analysis demonstrated that PS activity of < 10th percentile (odds ratio 5.9, 95 % confidence interval 1.7-18.1) and body mass index (BMI) ≥ 25 kg/m² (4.3, 1.1-13.3) were independent risk factors for severe PIH. Similarly, free PS level of < 5th percentile (4.4, 1.0-14.3) and BMI ≥ 25 kg/m² (4.0, 1.3-10.9) were independent risk factors for pre-eclampsia. In conclusion, women with low levels of plasma PS activity and free PS during early pregnancy might have increased risks of PIH, severe PIH or pre-eclampsia. Women with low FXII level might have an increased risk of PD at < 34 GW.

Reduced Protein C Activity Might be Associated With Progression of Peripheral Arterial Disease

We evaluated the effect of reduced activities of protein C (PC) and protein S (PS) on the progression of peripheral arterial disease (PAD). We measured PC and PS activities in 106 patients with PAD and 44 patients with abdominal aortic aneurysm (AAA) in the same period. The incidences of PC deficiency in PAD and AAA were 4.7% and 4.5%, respectively, and those of PS were 14.1% and 11.4%, respectively; these incidences were much higher than those in the normal population. The PC and PS activities were significantly lower in patients having critical limb ischemia (CLI) than in patients with intermittent claudication. In particular, lower PC activity and female gender were determinant factors of CLI in multivariate logistic regression analysis. We suggest that PC deficiency is an independent predictor for the progression of CLI.

A survey of the clinical course and management of Japanese patients deficient in natural anticoagulants

Few data are available on the clinical course of Japanese patients deficient in natural anticoagulants (antithrombin (AT), protein C, and protein S). We conducted a nationwide survey to reveal the clinical course of these patients. Questionnaires were sent to 321 council members of the Japanese Society on Thrombosis and Hemostasis, Japanese Society for Vascular Surgery, and Japanese Society of Phlebology. A total of 103 responses were obtained and data of 183 patients were collected. Of 183 patients, 142 (78%) experienced at least one episode of venous thromboembolism (VTE). The first VTE occurred before the age of 40 years in 71 patients (45%). Venous thromboembolism recurred in 15 (39%) patients with AT deficiency and 19 (18%) patients with other deficiencies. These findings suggest that half of the first episodes of VTE in patients deficient in natural anticoagulants occur before middle age and the risk of VTE recurrence is high in patients with AT deficiency.

Normal ranges and genetic variants of antithrombin, protein C and protein S in the general Chinese population. Results of the Chinese Hemostasis Investigation on Natural Anticoagulants Study I Group

BACKGROUND

Inherited deficiency of antithrombin, protein C and protein S, three important, naturally occurring coagulation inhibitors, might play a major role in the occurrence of venous thromboembolism in Chinese. The establishment of age- and gender-related normal ranges of these inhibitors is crucial for an accurate diagnosis of these deficiencies.

DESIGN AND METHODS

We designed a prospective cross-sectional study recruiting healthy adults from four university-affiliated hospitals in China. Antithrombin, protein C and protein S were studied by measuring their activity. Gene analysis was performed when natural anticoagulant deficiency was suspected. Polymorphisms of the factor V gene were searched for among subjects who were positive for activated protein C resistance.

RESULTS

In 3493 healthy Chinese adults (1734 men, 1759 women; age 17-83 years), we found higher age-adjusted activities for protein C and protein S in men than in women but no sex difference for antithrombin. In women, mean protein C and protein S activities increased with age. In men, mean protein C levels increased with age up to the age of 49 but decreased after 50 years old; mean protein S levels decreased after 50 years of age. Antithrombin levels remained stable over time in women but decreased significantly after 50 years of age in men. Reference values according to age and sex allowed the identification of 15 genetic variants (protein C:10, antithrombin:3, protein S:2) in subjects with protein activity below the 1(st) percentile.

CONCLUSIONS

This is the largest survey ever conducted in the healthy general Chinese population. These normal ranges provide the essential basis for the diagnosis and treatment of thrombosis in Chinese.

The association of protein S Tokushima-K196E with a risk of deep vein thrombosis

Deep vein thrombosis (DVT) is a multifactorial disease caused by acquired risk factors such as a bed rest, surgery and malignancies. Although the factor V Leiden and the prothrombin-20210G>A mutation do not exist in Japanese populations, a mutation in protein S (PS) Tokushima (K196E) has been attracting attention in Japan. In this study, the genetic contribution of PS Tokushima (K196E) was evaluated in 60 Japanese patients with thrombosis in comparison to 234 healthy volunteers and 88 patients without thrombosis. Genes associated with the response to warfarin, cytochrome P450 2C9 (CYP2C9), vitamin K epoxide reductase complex subunit 1 (VKORC1), and γ-glutamyl carboxylase (GGCX) were also investigated simultaneously. PS Tokushima (K196E) was detected in 6 patients with thrombosis, in 3 without thrombosis and in 3 healthy volunteers, indicating that there is a high frequency of the PS Tokushima (K196E). There were no significant differences of CYP2C9, VKORC1 or GGCX between the patients with and without DVT. Therefore, PS Tokushima (K196E) is an important genetic risk factor for DVT in the Japanese population.

Single nucleotide polymorphisms and haplotypes of protein C and protein S genes in the Thai population

Protein C (PC) and protein S (PS) play key roles in an anticoagulant pathway in order to control the haemostatic system. We identified single nucleotide polymorphisms (SNPs) and/or haplotypes in the promotor and exons of the whole PC and PS genes and in the 3'-untranslated region of the PS gene in 55 Thai individuals. The PC gene revealed 10 haplotypes. One synonymous SNP at 2196 was found in the normal Thai population with a minor allele frequency of 4.90%. One homozygous mutation in exon 7, R147W, co-segregated with the synonymous SNP 2196 (homozygote) of the PC gene, resulting in decreased PC activity and antigenic levels. The PS gene revealed three haplotypes with two frequent dimorphisms in exon 15 and the 3'-untranslated region. The most frequent haplotype in the PS gene was H3 (wild type). There was no correlation between the haplotypes of PC and PS genes with functional and antigenic levels of PC and PS.

Protein S and protein C gene mutations in Japanese deep vein thrombosis patients

OBJECTIVES

Coagulation factor V Leiden has not been detected in Japanese patients suffering from thrombosis. Hitherto, the constitutional background of Japanese thrombotic patients has never been systematically examined. We have performed a systematic investigation to determine pathogenesis for deep vein thrombosis in a Japanese population.

DESIGN AND METHODS

Routine coagulation and fibrinolysis tests were performed to determine the activities of protein S, protein C, antithrombin, plasminogen and fibrinogen. Gene analysis was performed in thrombotic patients having low activities of these factors.

RESULTS

Our study indicates that the frequency (19/85 = 0.22) of mutations of protein S gene in the Japanese patients was 5-10 times higher than that of mutations of protein S gene in Caucasian patients, and the frequency (8/85 = 0.09) of mutations of protein C gene was almost three times higher than that of Caucasian patients. The frequency of antithrombin gene mutation was similar in both populations.

CONCLUSION

Our study reinforces that the genetic anomaly in the protein S/protein C anticoagulation system is an important risk factor for thrombophilia in the Japanese population.

Deficiency of protein S-mediated familial venous thrombophilia--a case report

Deficiency of protein S causes potential problems of thrombosis. Cases of familial venous thrombosis due to deficiency of protein S were presented. First, an 85-year-old woman had pulmonary thromboembolism due to left deep femoral venous thrombosis, which might be triggered by leg fracture and the long-term treatment with a plaster cast. Next, her 29-year-old granddaughter had episodes of recurrent venous thrombosis in her legs and arms, which might be triggered by the treatment with a plaster cast and abortion. In the latter part, the aspects of risks for thromboembolism, potential problems in gestational period, and an advisability of thromboprophylaxis in patients with deficiency of protein S are described.

Hereditary protein s deficiency with a history of recurrent myocardial infarction

Protein S is a vitamin K-dependent plasma protein that inhibits the process of blood coagulation via activation of protein C, another vitamin K-dependent plasma protein A 58-year-old man with hereditary protein S deficiency had repeated attacks of acute myocardial infarction at age 52 and 58 years.

A review of the technical, diagnostic, and epidemiologic considerations for protein S assays

OBJECTIVES

To review the state of the art relating to protein S deficiency as a risk factor for thrombosis and to make recommendations regarding the use of protein S measurements in the assessment of thrombotic risk in individual patients and families.

DATA SOURCES, EXTRACTION, AND SYNTHESIS

Selection criteria were developed for the inclusion of publications from 1985 to 2001 based on the relevant literature concerned with the systematic review of diagnostic tests. Minimal selection criteria were agreed on and the articles stratified into level 1 if they met these criteria and level 2 if they did not meet these criteria. The included articles were reviewed by the authors and abstracted onto predetermined data collection forms. These forms were then scored and recommendations based on level 1 studies. As described elsewhere, results of discussions at the College of American Pathologists Conference XXXVI on Diagnostic Issues in Thrombophilia were used to revise the manuscript into its final form.

CONCLUSIONS

Consensus was reached on 16 recommendations for the use of protein S assays in the assessment of thrombotic risk in individuals and families. Two themes run through the conclusions. First, protein S assays are the most technically problematic of the assays reviewed at this conference. Second, only 2 papers evaluating the diagnostic use of protein S assays met our level 1 inclusion criteria. These 2 problems point out the need for better standardized assays and rigorous studies of the diagnostic utility of these assays.

Acquired activated protein C resistance is associated with the co-existence of anti-prothrombin antibodies and lupus anticoagulant activity in patients with systemic lupus erythematosus

Venous thromboembolism (VTE) is one of the common manifestations in the anti-phospholipid (aPL) syndrome. We examined the levels of IgG antibodies (Abs) to beta2-glycoprotein I (beta2-GP I) and prothrombin, lupus anticoagulant (LA) activity, activated protein C resistance (APC-R), and factor V Leiden in 96 patients with systemic lupus erythematosus (SLE); 19 with VTE and 77 without VTE. Acquired APC-R, which was not found in any patient with the factor V Leiden mutation, was present in 33 (34.4%) out of the 96 patients with SLE. The presence of acquired APC-R was a strong risk factor for VTE. The SLE patients were divided into four groups according to the results of enzyme-linked immunosorbent assay (ELISA) and LA activity for each aPL Abs: ELISA+, LA+; ELISA+, LA-; ELISA-, LA+; and ELISA-, LA-. A significant association was observed between APC-R and the co-existence of anti-beta2-GP I Abs and LA activity or of anti-prothrombin Abs and LA activity. There was no association between APC-R and the presence of anti-beta2-GP I Abs, anti-prothrombin Abs, or LA activity alone. However, when multivariate logistical regression analysis was performed, it was clear that only the co-existence of anti-prothrombin and LA activity was a significant risk factor for APC-R. These findings indicate that the co-existence of anti-prothrombin Abs and LA activity may be an important factor in the pathogenesis of acquired APC-R in patients with SLE.

Frequency of natural coagulation inhibitor (antithrombin III, protein C and protein S) deficiencies in Japanese patients with spontaneous deep vein thrombosis

One hundred and thirteen consecutive Japanese patients with deep venous thrombosis (DVT) were studied for the incidences of antithrombin III (AT-III), protein C (PC) and protein S (PS) deficiencies, and the results were compared with those of normal subjects. Ten of the 392 normal Japanese subjects were found with PS deficiency (n = 8, 2.02%) or PC deficiency (n = 2, 0.5%). PS deficiencies comprised type I (1/8, 12.5%), type 11 (4/8, 50%), and type III (3/8, 37.5%). All PC deficiencies were type I. Among patients with DVT, 32 (28.3%) were deficient in AT-III, PC and PS. These patients consisted of two AT-III deficiency (1.77%), nine PC deficiency (7.96%), 20 PS deficiency (17.7%), and one combined deficiency of PC and PS (0.88%). Both of the patients with AT-III deficiency were classified as type II, all those with PC deficiency as type I, and those with PS deficiency as type I in 25% (5/20), type II in 55% (11/20) and type III in 20% (4/20). The frequency of PC and PS deficiencies in patients with DVT were 15.6 and 7.38 times the control population frequency, respectively, and this difference was statistically significant (P < 0.05). These data suggest that the Japanese population has a high frequency of PC and PS deficiencies. We recommend that PS activity should be measured for screening of thrombosis since type II deficiency accounted for approximately 50% of PS deficiency cases in both patients and the normal group in the Japanese.