Liner dissociation in total hip arthroplasty: a systematic review.

OBJECTIVE: Liner dissociation (LD) is a rare catastrophic mechanical failure of total hip arthroplasty (THA). The study aims at reviewing the available literature regarding liner dissociations to point out their prevalence, describing any possible association and highlighting the surgical management at the time of revision. MATERIALS AND METHODS: A systematic review of the literature was conducted from January 2002, until February 2022, according to the PRISMA guidelines. The main keywords were: "dissociation" AND "liner" OR "hip arthroplasty" OR "THA" and their MeSH terms in any possible combination. Cases of liner dissociation with all levels of evidence of any age published in indexed journals were included. The study quality of all included studies was evaluated using the MINORS criteria. The kappa (k) value was used to assess the consensus between reviewers in the selection of articles and methodological quality assessment. Finally, a sub-analysis was performed specifically concerning the elderly population. RESULTS: Thirty-one manuscripts met the inclusion criteria of the systematic review (21 case reports and 10 case series). 124 LD in 123 patients, (53% females and 47% males) were evaluated. The overall prevalence of LD was 0.15%. The mean age at surgery was of 56.5 years (range 31-75 years). LD occurred in a primary surgery setting in 86% of the cases, at a mean time of presentation of 45.8 months after replacement surgery. 39.5% of the cups and 8.8% of the stems required revision. The mean follow-up after the revision was 18.4 months. Complications after revision occurred in 19.6% of cases, including 3 cases of re-dissociations. Re-revision was required in 13.6% of the revisions. The sub-analysis of the elderly population included 28 cases of LD identified in 10 manuscripts, with an average age of 73.5 years. CONCLUSIONS: LD is a rare but catastrophic mechanical complication of modular THA that requires implant revision. The LD is not related to a specific prosthetic implant, liner material or design, acetabular positioning within the safe zone or age group.

The JAK2 V617F mutation frequently occurs in patients with portal and mesenteric venous thrombosis.

BACKGROUND: Myeloproliferative disorders (MPDs) represent a risk factor for thrombosis in the portal, mesenteric, and hepatic districts. OBJECTIVE: We aimed to assess whether the Janus kinase 2 (JAK2) V617F mutation, an acquired mutation that occurs in MPD patients, is a risk factor for portal and mesenteric venous thrombosis (PMVT) independently of the presence of overt MPDs. PATIENTS AND METHODS: The medical histories of 99 patients presenting with PMVT were obtained. The presence of the JAK2 V617F and VHL 598C > T mutations was determined by polymerase chain reaction followed by restriction enzyme analysis and direct cycle sequence analysis. RESULTS: Over a 10-year period of observation, of the 99 patients presenting with PMVT, the JAK2 V617F mutation was detected in heterozygous state in 17 individuals [17.2%; 95% confidence interval (95% CI) 10.9-25.9]. None of the patients presenting with the JAK2 V617F mutation carried an inherited thrombophilic risk factor. Seven patients with (43.8%; 95% CI 19.8-70.1) and two without (2.4%; 95% CI 0.3-8.4) the JAK2 V617F mutation had a diagnosis of MPD at the occurrence of the venous thrombotic event. After a median follow-up of 41 months (range 3-114 months), three out of the 10 patients carrying the JAK2 V617F mutation were then diagnosed as having idiopathic myelofibrosis (n = 2) or polycythemia vera (n = 1), whereas in seven patients a MPD was not detected. Two of the 83 patients without the JAK2 V617F mutation went on to develop MPDs. CONCLUSIONS: Determination of the JAK2 V617F mutation may contribute to the search for genetic determinants of PMVT and may be useful to recognize patients who should be carefully observed for the subsequent development of overt MPDs.

Association of protein S p.Pro667Pro dimorphism with plasma protein S levels in normal individuals and patients with inherited protein S deficiency.

A dimorphism in PROS1 gene (c.A2,001G, p.Pro667Pro) has been associated with significantly reduced levels of both free and total protein S in carriers of the GG genotype. It is not known how the GG genotype could influence PS levels in normals, whether it could influence the levels of protein S in carriers of mutations in PROS1 gene and whether this genotype acts as an isolated or additive risk factor for venous thrombosis. With this as background, we evaluated the association of p.Pro667Pro dimorphism with free and total protein S centrally measured in a panel of 119 normal controls, 222 individuals with low protein S and 137 individuals with normal PS levels belonging to 76 families with protein S deficiency enrolled in the ProSIT study. Transient expression of recombinant wild type protein S and p.Pro667Pro protein S was performed to evaluate the role of the A to G transition at position 2001 in vitro. The p.Pro667Pro polymorphism was also expressed together with a p.Glu67Ala variant to assess a possible influence on protein S levels in protein S deficient subjects. Free and total protein S levels were significantly lower in normal women. In normal women only was the GG genotype associated with significantly lower free protein S levels in comparison to AA and AG genotypes (P=0.032). No significant influence of GG genotype was observed in patients, either with known mutations or with low protein S levels. These data were confirmed by in vitro transient expression, showing no difference in secretion levels of the p.Pro667Pro variant (even in association with the p.Glu67Ala mutation), compared to the wild type protein S. The genotype in itself was neither a significant risk factor for venous thrombosis nor a risk modifier in patients with known mutations.

Low protein Z levels and risk of occurrence of deep vein thrombosis.

BACKGROUND: Protein Z (PZ) serves as a cofactor for activated factor X inhibition by the PZ-dependent protease inhibitor. In vivo and in vitro studies aimed at investigating the role of PZ levels in venous thombosis have produced conflicting results. OBJECTIVES: We investigated whether reduced PZ levels and PZ gene common variants are associated deep vein thrombosis (DVT). PATIENTS AND METHODS: In 197 patients with DVT and in 197 age-matched and sex-matched controls, PZ plasma levels and gene polymorphisms were evaluated by means of an enzyme-linked immunosorbent assay and direct cycle sequence analysis. RESULTS: Similar PZ levels were found in controls (1.44; SD 0.63 microg mL-1) and in patients (1.44; SD 0.96 microg mL-1). The incidence of PZ levels below the 5.0 (0.52 microg mL-1) or the 2.5 percentile of controls (0.47 microg mL-1) was higher in patients (10.2% and 8.7%, respectively) than in controls {4.1% [odds ratio (OR) 2.7, 95% confidence interval (CI) 1.2-7.3], and 2.0% (OR 4.6, 95% CI 1.5-13.9), respectively}. This relationship was independent of the effect of age, sex, and factor V Leiden and FII A(20210) alleles [OR 2.8 (95% CI 1.1-7.3), and OR 4.9 (95% CI 1.4-17.3)]. PZ levels were associated with the intron C G-42A and the intron F G79A polymorphisms in cases (r2=0.129) and in controls (r2=0.140). However, frequencies of the PZ gene polymorphisms were similar in the two groups and were not associated with very low PZ levels. CONCLUSIONS: The present data suggest an association between very low PZ plasma levels and the occurrence of DVT, with PZ gene polymorphisms contributing little to this relationship.

Antibodies against beta2-glycoprotein I complexed with an oxidised lipoprotein relate to intima thickening of carotid arteries in primary antiphospholipid syndrome.

To explore whether antibodies against beta2-glycoprotein I (beta2GPI) complexed to 7-ketocholesteryl-9-carboxynonanoate (oxLig-1) and to oxidised low-density lipoproteins (oxLDL) relate to paraoxonase activity (PONa) and/or intima media thickness (IMT) of carotid arteries in primary antiphospholipid syndrome (PAPS). As many as 29 thrombotic patients with PAPS, 10 subjects with idiopathic antiphospholipid antibodies (aPL) without thrombosis, 17 thrombotic patients with inherited thrombophilia and 23 healthy controls were investigated. The following were measured in all participants: beta2GPI-oxLDL complexes, IgG anti-beta2GPI-oxLig-1, IgG anti-beta2GPI-oxLDL antibodies (ELISA), PONa, (para-nitrophenol method), IMT of common carotid (CC) artery, carotid bifurcation (B), internal carotid (IC) by high resolution sonography. Beta2GPI-oxLDL complex was highest in the control group (p < 0.01), whereas, IgG anti-beta2GPI-oxLig1 and IgG anti-beta2GPI-oxLDL were highest in PAPS (p < 0.0001). In healthy controls, beta2GPI-oxLDL complexes positively correlated to IMT of the IC (p = 0.007) and negatively to PONa after correction for age (p < 0.03). PONa inversely correlated with age (p = 0.008). In PAPS, IgG anti-beta2GPI-oxLig-1 independently predicted PONa (p = 0.02) and IMT of B (p = 0.003), CC, (p = 0.03) and of IC (p = 0.04). In PAPS, PONa inversely correlated to the IMT of B, CC and IC (p = 0.01, 0.02 and 0.003, respectively). IgG anti-beta2GPI-oxLig-1 may be involved in PAPS related atherogenesis via decreased PON activity.

Lymphocyte subpopulations and intima media thickness in primary antiphospholipd syndrome.

The aim of this study was to evaluate a possible association between lymphocyte subsets and intima media thickness (IMT) of carotid arteries in primary antiphospholipid syndrome (PAPS). We used a cross-sectional study on PAPS patients (n = 18) and healthy controls (n = 16). IgG anti-cardiolipin antibody (aCL), IgG anti-beta2glycoprotein-I (anti-beta2GPI), IgG anti-beta2glycoprotein-I complexed to oxidized low-density lipoprotein (oxLDL) and to a specific oxidized moiety of LDL (oxLig1), and beta2GPI-oxLDL were measured by ELISA. Lymphocyte immunophenotyping was performed using pairs of monoclonal antibodies directly labelled with fluorescein isothiocyanate, or phycoerythrin or phycoerythrin-Texas-red-X. Intima media thickness (IMT) of carotid arteries was determined by high-resolution sonography. Total peripheral blood lymphocytes did not differ between PAPS and controls. Memory CD4+/CD45RO + T cells were lower in PAPS than controls (P = 0.0007) as well as CD16+56+ natural killer cells (P = 0.02). In PAPS memory T CD45RO + cells positively correlated with IgG anti-beta2GPI-oxLigl (P = 0.002) and to IMT of carotid arteries (common carotid P = 0.02, bifurcation P = 0.007). Naive CD4+/CD45RA+ T cells inversely correlated with beta2GPI-oxLDL (P = 0.009). The relation between IgG anti-beta2GPI-oxLig1 and IMT of carotid arteries with memory CD45RO + T lymphocytes suggests a role for the latter in PAPS related atherogenesis.

A randomized clinical trial of high-intensity warfarin vs. conventional antithrombotic therapy for the prevention of recurrent thrombosis in patients with the antiphospholipid syndrome (WAPS).

BACKGROUND: The optimal intensity of oral anticoagulation for the prevention of recurrent thrombosis in patients with antiphospholipid antibody syndrome is uncertain. Retrospective studies show that only high-intensity oral anticoagulation [target international normalized ratio (INR) >3.0] is effective but a recent randomized clinical trial comparing high (INR range 3.0-4.0) vs. moderate (INR 2.0-3.0) intensities of anticoagulation failed to confirm this assumption. METHODS: We conducted a randomized trial in which 109 patients with antiphospholipid syndrome (APS) and previous thrombosis were given either high-intensity warfarin (INR range 3.0-4.5, 54 patients) or standard antithrombotic therapy (warfarin, INR range 2.0-3.0 in 52 patients or aspirin alone, 100 mg day(-1) in three patients) to determine whether intensive anticoagulation is superior to standard treatment in preventing symptomatic thromboembolism without increasing the bleeding risk. RESULTS: The 109 patients enrolled in the trial were followed up for a median time of 3.6 years. Mean INR during follow-up was 3.2 (SD 0.6) in the high-intensity warfarin group and 2.5 (SD 0.3) (P < 0.0001) in the conventional treatment patients given warfarin. Recurrent thrombosis was observed in six of 54 patients (11.1%) assigned to receive high-intensity warfarin and in three of 55 patients (5.5%) assigned to receive conventional treatment [hazard ratio for the high intensity group, 1.97; 95% confidence interval (CI) 0.49-7.89]. Major and minor bleeding occurred in 15 patients (two major) (27.8%) assigned to receive high-intensity warfarin and eight (three major) (14.6%) assigned to receive conventional treatment (hazard ratio 2.18; 95% CI 0.92-5.15). CONCLUSIONS: High-intensity warfarin was not superior to standard treatment in preventing recurrent thrombosis in patients with APS and was associated with an increased rate of minor hemorrhagic complications.

Premature atherosclerosis in primary antiphospholipid syndrome: preliminary data.

OBJECTIVE: To investigate the atherosclerosis hypothesis in primary antiphospholipid syndrome (PAPS). METHODS: The intima media thickness (IMT) of carotid arteries and other cardiovascular risk factors was measured in 20 patients with PAPS (mean (SD) age 35 (12) years) and in 20 controls matched for age and sex (34 (12) years). RESULTS: The frequency of smoking, hypertension, and dyslipidaemia was similar in the two groups, but plasma homocysteine was higher in patients with PAPS (mean (SD) 11.9 (6.2) v 8.2 (3.4) micromol/l, p = 0.037). The IMT was slightly greater in patients with PAPS than in controls at the carotid bifurcation (mean (SD) 0.61 (0.24) v 0.48 (0.09) mm, p = 0.04) and internal carotid artery (0.52 (0.22) v 0.40 (0.08), p = 0.01). These differences were more evident in patients aged >40 years than in those aged <30 years at the carotid bifurcation (0.76 (0.25) v 0.55 (0.06), p = 0.0007) and internal carotid artery (0.63 (0.25) v 0.45 (0.09), p = 0.02); no differences were seen in the younger age group compared with controls. CONCLUSION: Atherosclerosis is a possibility in patients with PAPS in their fourth decade of life or older.

Thrombophilic genotypes, natural anticoagulants, and plasma homocysteine in myeloproliferative disorders: relationship with splanchnic vein thrombosis and arterial disease.

The contribution of pro-thrombotic factors towards the development of arterial disease (AD) and splanchnic vein thrombosis (SVT) was retrospectively evaluated in 79 patients (39M, 40F, mean age 55 +/- 16 years) with myeloproliferative disorders (MPD) (essential thrombocythemia [n = 26], primary proliferative polycythemia [n = 27], and idiopathic myelofibrosis [n = 26]). Of these, 18 had AD and 17 SVT, the remaining 44 were non-thrombotic (NT). Plasma concentrations of natural anticoagulants, plasma homocysteine (HC), IgG anticardiolipin antibodies (aCL), and thrombophilic genotypes (methylenetetrahydrofolate reductase C(677)T, factor V Leiden, prothrombin G(20210)-->A) were determined. Isolated protein C deficiency was found in 23% of patients from the SVT group, in 5% from the AD group, in 6.8% from the NT group, and in 1% of historical controls (P = 0.0001). The prevalence of thrombophilic genotypes and that of the other natural anticoagulants did not differ across the groups. The proportion of patients with elevated plasma HC was 66% in the AD group, 27% in the non-thrombotic group, 12% in the SVT group and 4.5% in the control group (P < 0.0001). Patients with AD had higher plasma HC (24.4 +/- 23 micromol/L) than NT patients (12.3 +/- 7.7 micromol/L), SVT patients (9 +/- 4.9 micromol/L), and healthy controls (7.9 +/- 3 micromol/L) (P < 0.0001). In a logistic regression model lower protein C was independently associated with SVT, whereas elevated plasma HC was independently associated with AD. Measurement of plasma HC and protein C in MPD may identify patients more likely to suffer arterial disease and splanchnic vein thrombosis and who may require plasma HC lowering in the former case.

Portal vein thrombosis after variceal endoscopic sclerotherapy in cirrhotic patients: role of genetic thrombophilia.

BACKGROUND AND STUDY AIMS: Portal vein thrombosis is a rare event in patients with liver cirrhosis in the absence of a related neoplasm. Endoscopic sclerotherapy of esophageal varices has been anecdotally associated with the development of portal vein thrombosis. We tested the hypothesis that genetic thrombophilia plays a role in the development of portal vein thrombosis in patients with liver cirrhosis undergoing endoscopic sclerotherapy. PATIENTS AND METHODS: From June 1998 to December 1999, 61 consecutive patients underwent multiple sessions of endoscopic sclerotherapy for bleeding esophageal varices. Doppler ultrasound of the portal vein was performed before sclerotherapy and every 3 months thereafter. Antiphospholipid antibodies, factor V Leiden (FVL) mutation, prothrombin mutation G20210A (PTHRA20210) and mutation TT677 of methylenetetrahydrofolate reductase (MTHFR C677T) were evaluated in all patients. RESULTS: Portal vein thrombosis developed in 16 % of the patients (10 of 61) after a mean follow-up period of 16 months. A genetic cause for thrombosis was found in 70 % of patients with liver cirrhosis who developed portal vein occlusion, but only in 8 % of patients without this complication. CONCLUSIONS: Endoscopic sclerotherapy of esophageal varices may represent a trigger factor for portal vein thrombosis in cirrhotic patients with genetic thrombophilia.

Anticardiolipin antibody titre and plasma homocysteine level independently predict intima media thickness of carotid arteries in subjects with idiopathic antiphospholipid antibodies.

This study evaluated whether IgG anticardiolipin antibody (aCL) titre and traditional risk factors for atherosclerosis bore any relationship to the intima media thickness (IMT) of carotid arteries of patients with idiopathic antiphospholipid antibodies (aPL). IMT was assessed by high-resolution sonography at the common carotid, carotid bifurcation and internal carotid in 42 (13 male, 29 female, mean age 31+/-10 years) aPL subjects, 29 with primary thrombotic antiphospholipid syndrome and 13 with persistence of aPL in the absence of any underlying disorder. In the same subjects the following were measured: plasma fibrinogen (FNG), von Willebrand factor (vWF), plasminogen activator inhibitor (PAI), homocysteine (HC), total cholesterol (CHO), triglycerides (TG), high density and low density lipoprotein (HDL and LDL), platelet numbers and aCL of IgG and IgM isotype. IMT of the internal carotid was greater in males than females (0.48+/-0.03 vs 0.39+/-0.01 mm, P=0.02). IMT of the carotid bifurcation was greater in thrombotic than nonthrombotic subjects (0.50+/-0.02 vs 0.42+/-0.02 mm, P=0.04). By simple regression, IMT of the common carotids correlated with age (P< 0.0001) IgG aCL titre (P=0.001), FNG (P=0.006), LDL (0.01), CHO (0.02) and PAI (P=0.02). IMT of the carotid bifurcation correlated with age (P=0.002), IgG aCL titre (P=0.0002), FNG (P=0.0001), HC (P=0.009), CHO (P=0.02), vWF (P=0.01) and number of thrombotic events (P=0.03). IMT of the internal carotids correlated with age (P=0.002), IgG aCL titre (P=0.0001), FNG (P=0.0008), PAI (P=0.002) and HC (P=0.01). By stepwise multiple regression analysis, IgG aCL titre independently predicted IMT at all carotid segments examined (P always <0.005). In addition, plasma FNG and HC also resulted independent predictors of IMT at the carotid bifurcation (P=0.001 and P<0.0001, respectively) and internal carotid (P=0.03 and P<0.0001, respectively). These data strongly support an atherogenic role for IgG aCL in patients with aPL. Measurement of plasma HC and FNG may help define aPL subjects at higher vascular risk who may require lowering of HC and FNG by vitamin and/or pharmacologic intervention.

Multiple thrombophilic factors in a patient with Budd-Chiari syndrome.

Myeloproliferative disorders are the main cause of Budd-Chiari syndrome in western countries. Inherited or acquired thrombophilic factors have also been implicated. A novel mutation of the prothrombin gene (G-->A20210) has only been described in a few cases of Budd-Chiari syndrome so far. Venous thrombosis is often the result of multiple concomitant thrombophilic factors. We report the case of a patient with essential thrombocythemia and Budd-Chiari syndrome in which heterozygosity for both factor V Leiden and the mutation G20210A of the prothrombin gene were identified.

Impact of plasma homocysteine and prothrombin G20210 A on primary antiphospholipid syndrome.

The prevalence of prothrombin (PT) G20210A and methylenetetrahydrofolate reductase (MTHFR) C677 <-- T was assessed in 40 patients with primary antiphospholipid syndrome (APS) (14 male, 26 female; mean age, 37 +/- 14 years) and in 27 persistent carriers of antiphospholipid antibodies (aPL) (five male, 22 female; mean age, 40 +/- 16 years) without underlying diseases. Non-APS thrombotic patients (n = 100; 47 female, 53 male; mean age, 40 +/- 10 years) and healthy subjects (n = 100; 46 female, 54 male; mean age, 56 +/- 16 years) served as control groups. Plasma homocysteine (HC) (enzyme-linked immunosorbent assay) was measured in all aPL patients and in 51 subjects from the healthy control group (mean age, 38 +/- 16 years). Heterozygous prothrombin PT G20210A was more frequent in the thrombotic group without APS (18%) than in the control (4%), APS (12%) or aPL (11%) groups, whereas homozygous MTHFR C677 <-- T was equally distributed. After genotype sub-grouping, plasma HC was higher in APS patients with homozygous MTHFR C677 <-- T compared with non-homozygous APS patients (22 +/- 5.4 versus 11 +/- 1.3 micromol/l; P < 0.01) and with homozygous MTHFR C677 <-- T controls (22 +/- 5.4 versus 15 +/- 2.0 micromol/l). In the APS group, mean age at first event was lower in homozygous MTHFR C677 <-- T patients than in non-homozygous patients (26 +/- 7.5 versus 36 +/- 13 years; P = 0.008). In the same group, homozygous MTHFR C677 <-- T patients suffered an increased average number of events per person than non-homozygous patients (1.9 versus 1.3; P = 0.04). Heterozygous PT G20210A contributes little to the thrombotic tendency of primary APS whereas plasma HC may influence age at first event and number of events. Measurement of plasma HC in aPL subjects may identify patients at increased thrombotic risk requiring HC lowering.

Improved confirmation of weak lupus anticoagulants by employing sensitive and insensitive reagents to the lupus anticoagulant.

Detection of a lupus anticoagulant (LA) is of major importance to detect a thrombotic tendency. Confirmation of its phospholipid dependency may represent a tricky step in the diagnostic algorithm for LA, as several tests may yield borderline results of little diagnostic help. To improve on this point, we had previously employed a procedure comparing sensitive [rabbit brain kaolin (RBK)] and insensitive [soy bean phosphatides (SBP)] reagents to LA to screen and confirm LA at the same time in activated partial thromboplastin systems (aPTT). Here we compared its performance against a platelet neutralization procedure (PNP). To allow comparisons of our procedures with the PNP, a percentage ratio correction was calculated according to the following formula: [(RBK ratio - SBP ratio) x 100]/ RBK ratio. Similarly for the PNP: percentage ratio correction = [(buffer ratio - platelet phospholipid ratio) x 100]/buffer ratio. On 44 known LA plasmas, the PNP, expressed in seconds, yielded 15 (34%) negative or borderline results. After ratio transformation, the PNP still yielded 10 of 15 (66%) uncertain results, whereas the RBK/SBP procedure did not give any uncertain results (P = 0.0002). The mean percentage ratio correction was far superior for the RBK/SBP procedure than for the PNP (53.24 +/- 15.93 versus 20.28 +/- 12.15%, P < 0.0001). The use of sensitive and insensitive reagents to the lupus anticoagulant increases the confirmatory yield of LA in aPTT systems and may deserve inclusion amongst the confirmatory procedures for its diagnosis.

Inherited thrombophilic risk factors in a large cohort of individuals referred to Italian thrombophilia centers: distinct roles in different clinical settings.

BACKGROUND AND OBJECTIVES: Despite inherited thrombophilic risk factors being strongly associated with vein thrombosis, decisions on whether to screen subjects for these factors vary in different clinical settings. DESIGN AND METHODS: We calculated the prevalence of inherited thrombophilic risk factors in a large cohort of patients (n=1,238) with different clinical manifestations of vein thromboembolism. In the present cohort, screening for inherited thrombophilia was worthwhile among patients who developed vein thrombosis of the leg or cerebral vein thrombosis. Carriers of FV Leiden or FII A(20210) mutation more frequently had had deep vein thrombosis of the leg (OR: 4.35; 95% CI: 3.39-5.60), superficial vein thrombosis (OR: 3.34; 95% CI: 2.06-5.41), or cerebral vein thrombosis (OR: 2.77; 95% CI: 1.10-6.96). RESULTS: The screening program appeared to have a limited relevance in patients with isolated pulmonary embolism (OR: 2.13; 95% CI: 1.28-3.54), or mesenteric vein thrombosis (OR: 2.05; 95% CI: 1.22-3.44). INTERPRETATION AND CONCLUSIONS: The lack of association with inherited thrombophilia does not justify routine screening of patients with thrombosis of the upper extremities or with retinal vein thrombosis.

High prevalence of thrombophilic genotypes in patients with acute mesenteric vein thrombosis.

OBJECTIVES: Mesenteric vein thrombosis is a rare but severe abdominal emergency, often requiring intestinal resection. New genetic prothrombotic defects such as factor V Leiden, the prothrombin transition G20210A, and the methylenetetrahydrofolate reductase TT677 genotype have been described in association with venous thrombosis. Our goal was to assess prevalence and clinical significance of genetic thrombophilia in mesenteric vein thrombosis. METHODS: Twelve patients with acute mesenteric vein thrombosis were compared with 431 healthy people from the same geographical area. The factor V Leiden, the prothrombin transition G20210A, and the methylenetetrahydrofolate reductase TT677 genotype were identified by polymerase chain reaction and restriction analysis. RESULTS: A thrombophilic genotype was present in 9 patients (75%): the methylenetetrahydrofolate reductase TT677 genotype was present in 6 (50%), the factor V Leiden in 3 (25%), and the prothrombin transition G20210A in 3 (25%). Combined mutations were present in 4 (33%) patients. CONCLUSIONS: The factor V Leiden, the prothrombin transition G20210A, and the methylenetetrahydrofolate reductase TT677 genotype are important predisposing factors in the pathogenesis of mesenteric vein thrombosis. Their identification bears strong clinical implications for management of patients with mesenteric vein thrombosis.