Genetic analysis, phenotypic diagnosis, and risk of venous thrombosis in families with inherited deficiencies of protein S

Blood ◽  
2000 ◽  
Vol 95 (6) ◽  
pp. 1935-1941 ◽  
Author(s):  
Michael Makris ◽  
Michael Leach ◽  
Nick J. Beauchamp ◽  
Martina E. Daly ◽  
Peter C. Cooper ◽  
...  
Keyword(s):  
Venous Thrombosis ◽  
Protein S ◽  
Structural Defects ◽  
Protein S Deficiency ◽  
Gene Defect ◽  
Thrombotic Risk ◽  
Free Protein ◽  
First Degree Relatives ◽  
S Deficiency ◽  
Increased Risk

Abstract Protein S deficiency is a recognized risk factor for venous thrombosis. Of all the inherited thrombophilic conditions, it remains the most difficult to diagnose because of phenotypic variability, which can lead to inconclusive results. We have overcome this problem by studying a cohort of patients from a single center where the diagnosis was confirmed at the genetic level. Twenty-eight index patients with protein S deficiency and a PROS1 gene defect were studied, together with 109 first-degree relatives. To avoid selection bias, we confined analysis of total and free protein S levels and thrombotic risk to the patients' relatives. In this group of relatives, a low free protein S level was the most reliable predictor of a PROS1gene defect (sensitivity 97.7%, specificity 100%). First-degree relatives with a PROS1 gene defect had a 5.0-fold higher risk of thrombosis (95% confidence interval, 1.5-16.8) than those with a normal PROS1 gene and no other recognized thrombophilic defect. Although pregnancy/puerperium and immobility/trauma were important precipitating factors for thrombosis, almost half of the events were spontaneous. Relatives with splice-site or major structural defects in the PROS1 gene were more likely to have had a thrombotic event and had significantly lower total and free protein S levels than those relatives having missense mutations. We conclude that persons withPROS1 gene defects and protein S deficiency are at increased risk of thrombosis and that free protein S estimation offers the most reliable way of diagnosing the deficiency.

Free and Total Protein S Antigen Levels on the Risk of Venous Thrombosis: Results From the MEGA Study

Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 538-538
Author(s):  
Daniel D. Ribeiro ◽  
Maria Carolina T. Pintao ◽  
Willem M. Lijfering ◽  
Pieter H. Reitsma ◽  
Frits R. Rosendaal
Keyword(s):  
Venous Thrombosis ◽  
Total Protein ◽  
Protein S ◽  
Type I ◽  
Protein S Deficiency ◽  
Blood Draw ◽  
Free Protein ◽  
Type Iii ◽  
S Deficiency ◽  
Increased Risk

Abstract Abstract 538 Context: Conflicting data have been reported on the risk for venous thrombosis in individuals with low total protein S levels (i.e. type I protein S deficiency) and low free protein S levels with normal total protein S levels (i.e. type III protein S deficiency). This may be due to small numbers, wrong cut off level or inclusion of individuals with mild transitory decrements in protein S levels. Most studies that showed that type I and type III protein S deficiency were related with an increased risk for venous thrombosis, have been performed in thrombophilic families, suggesting that these deficiencies are inherited. As the prevalence of inherited type I or type III protein S deficiency is not known, the relevance of these findings within normal populations remain to be established. Objectives: To assess the risk of first venous thrombosis in persons with low levels of free protein S or total protein S in a large population-based case–control study. Design: MEGA study, 4956 consecutive patients aged 18 to 70 years with a first episode of venous thrombosis were included. Age- and sex-matched controls were partners of patients (n=3297) or individuals recruited by random digit dialing (n=3000). DNA was obtained by standard methods and was available for 4485 patients and 4889 control subjects. Citrated plasma was available for 2471 patients and 2940 controls. Molecular basis for protein S deficiency was investigated by analysis of copy number variation of PROS1 and sequencing of individuals with the lowest levels of protein S in attempt to explain the different findings in risk estimates between families and population studies. Statistical analysis: Odds ratios were adjusted for age and sex (matching factors) for levels of free/total protein S and their 95% confidence levels (95% CIs) with the use of logistic regression. The 2.5th-97.5th percentile of both total and free protein S in control subjects that did not use vitamin K antagonists (VKA) at time of blood draw were considered as the reference range. Individuals that used VKA at time of blood draw were excluded when calculating relative risk estimates. Furthermore, a preplanned sensitivity analysis was performed where we excluded estrogen users and pregnant women at time of blood draw. Results: Individuals with low free protein S levels or low total protein S levels (<2.5th percentile) were not at increased risk of venous thrombosis as compared to individuals with protein S levels in the 2.5th-97.5th percentile; odds ratio 0.82 (95% CI, 0.56–1.21) and 0.90 (95% CI, 0.62–1.31) respectively. Excluding all women who used estrogens or were pregnant/puerperic at time of venous thrombosis or at time of blood sampling increased the odds ratios slightly to 1.55 (95% CI, 0.84–2.88) for individuals with low free protein S levels and to 1.28 (95% CI, 0.70–2.35) in individuals with low total protein S levels. We subsequently compared decreasing cut off values of free and total protein S levels on the risk of venous thrombosis as compared to the same reference group. Although numbers became small, it appeared that a free protein S cut off level of < 0.20th or < 0.10th percentile could identify individuals at high risk of venous thrombosis (odds ratios 2.01; 95% CI, 0.57–7.15, and 5.44; 95% CI, 0.61–48.78, respectively). Even extremely low (<0.10th percentile) total protein S levels were not associated with venous thrombosis. Only one patient had a copy number variation of PROS1 in 2270 consecutive samples tested. Currently, we are sequencing the PROS1 gene in all individuals with protein S levels <1st percentile of which results will be available before the ASH conference of 2011. Conclusion: Low free protein S and low total protein S levels could not identify individuals at risk for venous thrombosis in a population based study. Although extremely low free protein S levels were associated with an increased risk for venous thrombosis, numbers were too small to support testing on free protein S in an unselected group of venous thrombosis patients. Disclosures: No relevant conflicts of interest to declare.

Severe Arterial Cerebral Thrombosis in a Patient with Protein S Deficiency (Moderately Reduced Total and Markedly Reduced Free Protein S): A Family Study

1989 ◽  
Vol 61 (01) ◽  
pp. 144-147 ◽  
Author(s):  
A Girolami ◽  
P Simioni ◽  
A R Lazzaro ◽  
I Cordiano
Keyword(s):  
Arterial Thrombosis ◽  
Protein C ◽  
Protein S ◽  
Protein S Deficiency ◽  
Protein C Deficiency ◽  
Free Protein ◽  
Her Family ◽  
S Deficiency ◽  
Increased Risk ◽  
Patient Reported

SummaryDeficiency of protein S has been associated with an increased risk of thrombotic disease as already shown for protein C deficiency. Deficiencies of any of these two proteins predispose to venous thrombosis but have been only rarely associated with arterial thrombosis.In this study we describe a case of severe cerebral arterial thrombosis in a 44-year old woman with protein S deficiency. The defect was characterized by moderately reduced levels of total and markedly reduced levels of free protein S. C4b-bp level was normal. Protein C, AT III and routine coagulation tests were within the normal limits.In her family two other members showed the same defect. All the affected members had venous thrombotic manifestations, two of them at a relatively young age. No other risk factors for thrombotic episodes were present in the family members. The patient reported was treated with ASA and dipyridamole and so far there were no relapses.

Free Protein S Deficiency Is a Risk Factor for Venous Thrombosis

1997 ◽  
Vol 78 (05) ◽  
pp. 1343-1346 ◽  
Author(s):  
Elena M Faioni ◽  
Carla Valsecchi ◽  
Alessandra Palla ◽  
Emanuela Taioli ◽  
Cristina Razzari ◽  
...  
Keyword(s):  
Risk Factor ◽  
Relative Risk ◽  
Venous Thrombosis ◽  
Protein S ◽  
Unexpected Finding ◽  
Reference Ranges ◽  
Protein S Deficiency ◽  
Men And Women ◽  
Free Protein ◽  
S Deficiency

SummaryA recent study suggests that protein S deficiency is not a risk factor for venous thrombosis. Since this unexpected finding would have important clinical implications if confirmed, we performed a case-control study with the aim to determine the prevalence of protein S deficiency in patients with thrombosis and in healthy individuals taken from the general population and the relative risk of thrombosis in protein S-deficient patients. Free protein S concentration was measured in 327 consecutive patients with at least one venous thrombotic episode and in 317 age- and sex-matched control individuals. Different normal reference ranges were obtained and adopted for men and women. Protein S deficiency was found in 3.1% (95% Cl: 1.5-5.2) of patients and in 1.3% of controls (95% Cl: 0.3-2.8). Ten patients and 4 control subjects had protein S deficiency, which determined a relative risk of thrombosis (sex- and age-adjusted odds ratio) of 2.4 (95% Cl: 0.8-7.9). When men and women were analyzed separately, the risk was 5.0 (95% CI: 0.6-43.6) and 1.6 (95% Cl: 0.4-6.7) respectively. PS-deficient men had more thrombotic episodes than women and later in life. Multivariate analysis established that sex was an independent determinant of the number of episodes, as was age, while PS deficiency was not. However sex and PS deficiency status were both determinants of age at first thrombotic episode.

FAMILIAL TYPE I PROTEIN S DEFICIENCY ASSOCIATED WITH SEVERE VENOUS THROMBOSIS. A STUDY OF FIVE CASES

1987 ◽  
Author(s):  
C Boyer-Neumann ◽  
M Wolf ◽  
J Amiral ◽  
A M Guyager ◽  
D Meyer ◽  
...  
Keyword(s):  
Venous Thrombosis ◽  
Plasma Protein ◽  
Active Form ◽  
Vena Cava ◽  
Protein S ◽  
Immunological Methods ◽  
Type I ◽  
Protein S Deficiency ◽  
Free Protein ◽  
S Deficiency

Protein S deficiency has been demonstrated in 5 members from the same family with a history of severe recurrent venous thrombosis over three generations. The propositus, a 16 year old female, had a first spontaneous thrombotic episode at age 15. Phlebography revealed a total obstruction of her left ilio-femoral vein with an extension to the vena cava. She was treated with heparin followed by oral anticoagulant therapy. The four other affected members (mother, aunts and uncle of the propositus) had also presented recurrent thrombosis with onset at a young age. The grandfather, not tested, had died from massive pulmonary embolism at age 54. The immunological assay of protein S was performed in plasma by Laurell, using a monospecific antiserum to human protein S, or by an ELISA, using a kit from Diagnostica Stago (Asserachrom Protein S). In order to separate free protein S, the functionally active form, from protein S complexed with C4-binding protein, plasma was adsorbed with 3.75 % polyethyleneglycol (PEG 6000). Following PEG precipitation, the levels of free protein S antigen remaining in the supernatant were quantitated by the usual immunological methods. In addition, two-dimensional immunoelectrophoresis (DDIE) also provided information on the distribution of both forms. In plasma protein S levels were decreased (40 to 55 % of the normal range) in two untreated patients and lower levels (17 to 20 96) were observed in the three others, including the propositus, who were under dicoumarol therapy. In PEG treated-plasma, protein S was undetectable (less than 5 %) in all patients, indicating a lack of free protein S. This was confirmed by DDIE : whereas protein S migrated as two distinct peaks, corresponding to free and complexed protein S in normal plasma, only a single peak of complexed protein S was observed in all affected patients. These results clearly demonstrate a total lack of free protein S which appears to be responsible for the thromboembolic disorder in this family as there was no deficiency of the other plasma inhibitors (antithrombin III, heparin cofactor II and protein C). According to the classification recently proposed by Comp et al., this family belongs to type I protein S deficiency, with an autosomal dominant mode of inheritance.

scholarly journals Free protein S deficiency in a family with venous thrombosis

1990 ◽  
Vol 12 (5) ◽  
pp. 541-544 ◽  
Author(s):  
Carl G. Lauer ◽  
Thomas J. Reid ◽  
Carol S. Wideman ◽  
Bruce L. Evatt ◽  
Barbara M. Alving
Keyword(s):  
Venous Thrombosis ◽  
Protein S ◽  
Protein S Deficiency ◽  
Free Protein ◽  
S Deficiency

Hormonal State rather than Age Influences Cut-off Values of Protein S: Reevaluation of the Thrombotic Risk Associated with Protein S Deficiency

1999 ◽  
Vol 82 (09) ◽  
pp. 1093-1096 ◽  
Author(s):  
G. Liberti ◽  
R. M. Bertina ◽  
F. R. Rosendaal
Keyword(s):  
Total Protein ◽  
Protein S ◽  
Independent Effect ◽  
Healthy Population ◽  
Reference Ranges ◽  
Protein S Deficiency ◽  
Thrombotic Risk ◽  
Free Protein ◽  
S Deficiency ◽  
Menopausal State

SummaryOf the well known risk factors for thrombosis protein S deficiency is one of the most difficult to diagnose with certainty. Reliable estimates for the prevalence of protein S deficiency in the general population are not available and the risk of thrombosis is a controversial issue. It has been shown that levels of protein S fluctuate over time. However the determinants of low levels of protein S in the healthy population are not clear. Therefore, we evaluated the influence of sex, age and hormonal state on the antigen levels of protein S in 474 healthy control subjects of the Leiden Thrombophilia Study (LETS). In univariate analysis, sex, age, oral contraceptive (OC) use and post-menopausal state all influenced protein S antigen levels. In a multivariate model for the whole sample only menopausal state and OC use had still an effect on the levels of total protein S and only menopausal state had an independent effect on the values of free protein S. On the basis of this analysis we established different cut-off levels for these subgroups and we re-evaluated in the Leiden Thrombophilia Study the risk of thrombosis for individuals with low protein S using these different reference ranges. With these specific cut-off points, we did not observe an increase in the risk of thrombosis in patients deficient of total protein S (OR 1.2, 95% CI 0.5-2.9) or free protein S (OR 1.3, 95% CI 0.5-3.5). When men and women were analyzed separately, the risk in women was 1.5 (95% CI 0.4-5.4) and 2.4 (95% CI 0.6-9.2) for total and free protein S deficiencies, respectively; and there was no increase in thrombotic risk for men. We conclude that it may be helpful to apply separate cut-off levels in the assessment of protein S levels. This does not, however explain the differences between our results and those of others in the estimate of thrombotic risk of protein S deficiency.

Free protein S deficiency in a family with venous thrombosis

1990 ◽  
Vol 12 (5) ◽  
pp. 541-544 ◽  
Author(s):  
Carl G. Lauer ◽  
Thomas J. Reid ◽  
Carol S. Wideman ◽  
Bruce L. Evatt ◽  
Barbara M. Alving
Keyword(s):  
Venous Thrombosis ◽  
Protein S ◽  
Protein S Deficiency ◽  
Free Protein ◽  
S Deficiency

Analytical Considerations for Free Protein S Assays in Protein S Deficiency

2001 ◽  
Vol 86 (11) ◽  
pp. 1144-1147 ◽  
Author(s):  
Andreas Hillarp ◽  
Björn Dahlbäck ◽  
Kristina Persson
Keyword(s):  
Venous Thrombosis ◽  
Room Temperature ◽  
Protein S ◽  
Free Form ◽  
Protein S Deficiency ◽  
Sample Handling ◽  
Free Protein ◽  
Standard Curve ◽  
Assay Procedure ◽  
S Deficiency

SummaryProtein S is an anticoagulant protein that circulates in plasma in complex with C4b-binding protein (C4BP) or in free form. Deficiency of protein S increases the risk of venous thrombosis. Measurement of free protein S, as compared to total levels, has been shown to be superior for prediction of protein S deficiency. We studied the effects of different handling protocols for an immuno- and a ligand (C4BP)-based assay for free protein S. When the assay was performed at 37° C, the levels of free protein S in plasma from protein S deficient patients were approximately twice those obtained at room temperature. The reason for this phenomenon was that plasmas from protein S deficient patients exhibited a time-, temperature-, and dilution-dependent increase in free protein S, which was more pronounced than corresponding dilution of the normal plasma that was used to create the standard curve. These findings demonstrate the importance of assay procedure and sample handling in assays for free protein S.

The Frequency of Type I Heterozygous Protein S and Protein C Deficiency in 141 Unrelated Young Patients with Venous Thrombosis

1988 ◽  
Vol 59 (01) ◽  
pp. 018-022 ◽  
Author(s):  
C L Gladson ◽  
I Scharrer ◽  
V Hach ◽  
K H Beck ◽  
J H Griffin
Keyword(s):  
Venous Thrombosis ◽  
Protein C ◽  
Antithrombin Iii ◽  
Young Patients ◽  
Protein S ◽  
Type I ◽  
Protein S Deficiency ◽  
Protein C Deficiency ◽  
Low Protein ◽  
S Deficiency

SummaryThe frequency of heterozygous protein C and protein S deficiency, detected by measuring total plasma antigen, in a group (n = 141) of young unrelated patients (<45 years old) with venous thrombotic disease was studied and compared to that of antithrombin III, fibrinogen, and plasminogen deficiencies. Among 91 patients not receiving oral anticoagulants, six had low protein S antigen levels and one had a low protein C antigen level. Among 50 patients receiving oral anticoagulant therapy, abnormally low ratios of protein S or C to other vitamin K-dependent factors were presented by one patient for protein S and five for protein C. Thus, heterozygous Type I protein S deficiency appeared in seven of 141 patients (5%) and heterozygous Type I protein C deficiency in six of 141 patients (4%). Eleven of thirteen deficient patients had recurrent venous thrombosis. In this group of 141 patients, 1% had an identifiable fibrinogen abnormality, 2% a plasminogen abnormality, and 3% an antithrombin III deficiency. Thus, among the known plasma protein deficiencies associated with venous thrombosis, protein S and protein C. deficiencies (9%) emerge as the leading identifiable associated abnormalities.

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