Depression and cognitive deficits as long-term consequences of thrombotic thrombocytopenic purpura.

BACKGROUND: Thrombotic thrombocytopenic purpura (TTP) is an acute life-threatening microangiopathy with a tendency of relapse characterized by consumptive thrombocytopenia, microangiopathic hemolytic anemia, and spontaneous von Willebrand factor-induced platelet clumping leading to microthrombi. The brain is frequently affected by microthrombi leading to neurologic abnormalities of varying severity. STUDY DESIGN AND METHODS: The aim of this observational cohort study was to investigate the prevalence of depression and cognitive deficits in 104 patients having survived acute TTP. TTP survivors were repeatedly assessed by means of different standardized questionnaires to evaluate depression (IDS-SR) and mental performance (FLei). We received answers of 104 individual TTP patients and 55 of them participated in both surveys. RESULTS: Seventy-one of the 104 responding TTP patients (68%) suffered from depression and the severity of depression was similar in both surveys performed 1 year apart. Furthermore, TTP patients had considerably lower cognitive performance than controls. There was no correlation between prevalence of depression and cognitive deficits and the number and the severity of acute episodes. Impairment of mental performance correlated with the severity of depression (rs  = 0.779). CONCLUSION: The prevalence of depression and cognitive deficits was significantly higher in TTP patients. Cognitive impairment seemed to be a consequence of depression, almost independently of number and severity of TTP episodes.

Idiopathic thrombotic thrombocytopenic purpura: strongest risk factor for relapse from remission is having had a relapse.

BACKGROUND: Thrombotic thrombocytopenic purpura (TTP) is a rare, episodic clinical syndrome involving the production of thrombi in the microvasculature accompanied by thrombocytopenia and symptoms of organ ischemia. Idiopathic TTP develops when a patient produces antibodies that react with the protease ADAMTS13. The course after an episode is unpredictable; patients may relapse frequently or never. There is no laboratory value that can reliably predict potential relapse. STUDY DESIGN AND METHODS: To assess diagnostic and predictive values for risk of relapse, plasma samples from 27 patients with idiopathic TTP in remission were analyzed for anti-ADAMTS13 immunoglobulin (Ig)G, ADAMTS13 activity, and ADAMTS13 inhibitor titer. Patients were recruited at the Department of Hematology at the University Medical Center, Johannes Gutenberg University Mainz, Mainz, Germany. RESULTS: Anti-ADAMTS13 IgG was detected in 12 patients (44%); their median level of ADAMTS13 activity was nondetectable. Patients with anti-ADAMTS13 IgG had a median number of three previous relapses, whereas the 15 patients without presence of IgG (56%) had a median number of one previous relapse (p < 0.001; Mann-Whitney U test). The concentration of free anti-ADAMTS13 IgG and the levels measuring inhibitory activity (Bethesda unit) were positively correlated. CONCLUSION: A subgroup of TTP patients in remission with anti-ADAMTS13 IgG and nondetectable ADAMTS13 activity showed an increased risk for relapsing disease as demonstrated by their number of past relapses. The positive correlation we observed between anti-ADAMTS13 IgG and inhibitor levels supports the theory of ADAMTS13 inhibition as the crucial mechanism causing severe deficiency in ADAMTS13 activity in TTP.

The Influence of Hypothyroid Metabolic Status on Blood Coagulation and the Acquired von Willebrand Syndrome.

The intent of this prospective study aimed to identify the influence of hypothyroid metabolic status on the coagulation and fibrinolytic system and association with the acquired von Willebrand syndrome (VWS-ac). We compared 54 patients without substitution therapy after radical thyroidectomy with 58 control subjects without pathological thyroid-stimulating-hormone (TSH)-values. Patients with TSH > 17.5 mU/L over a period of >4 weeks were included. The control-collective was selected based on age and sex to match the patient-collective. The data were collected using laboratory coagulation tests and patient questionnaires; a bleeding score was determined. There were significant differences in the measurement of activated-partial-thromboplastin-time (aPTT/p = 0.009), coagulation-factor VIII (p < 0.001) and von-Willebrand-activity (VWF-ac/p = 0.004) between the patient and control groups. The patient cohort showed an increased aPTT and decreased factor VIII and VWF-ac. 29.7% of the patient-collective compared to 17.2% of the control subjects met the definition of VWS-Ac (p = 0.12). The bleeding score showed significantly more bleeding symptoms in patients with a laboratory constellation of VWS-ac (no family history; p = 0.04). Our results suggest hypocoagulability in hypothyroid patients. Hypothyroidism appears to have a higher incidence of VWS-ac. The increased risk of bleeding complications in hypothyroid patients may be of relevant importance for the outcome, especially in the context of invasive interventions.

The role of human leukocyte antigens as predisposing and/or protective factors in patients with idiopathic thrombotic thrombocytopenic purpura.

Fifty-four adult German patients suffering from idiopathic thrombotic thrombocytopenic purpura (TTP) have been examined for HLA class II. All patients presented autoantibodies against ADAMTS13 and ADAMTS13 activity levels <5%. Blood samples have been analyzed for HLA-DRB1 and DQB1 alleles using sequence-specific primer PCR and sequence-specific oligonucleotide PCR. Reference data of German bone marrow and blood donors were obtained from www.allelefrequencies.net. The results were evaluated employing two-sided binomial tests, and p values were corrected using the Benjamini-Hochberg procedure. A significant accumulation for DQB1*02:02 (p < 0.001) and DRB1*11 (p = 0.003) was found within the patient group. Twenty percent (DQB1*02:02) or 48.1% (DRB1*11) of TTP patients were tested positive for the particular HLA antigen compared to 1.2% (DQB1*02:02) or 23.5% (DRB1*11) in the control group. A tendency for a reduced occurrence of HLA-DRB1*04 was revealed (7.4% in patients compared to 24.6% in controls). An association between the HLA antigens DQB1*02:02 and DRB1*11 and disease susceptibility for idiopathic TTP has been found. A higher risk for disease outbreak within persons carrying the mentioned alleles can be assumed. The reduced occurrence of HLA-DRB1*04 in TTP patients indicates a possible protective effect of this HLA allele in disease development.

Influence of Personality, Resilience and Life Conditions on Depression and Anxiety in 104 Patients Having Survived Acute Autoimmune Thrombotic Thrombocytopenic Purpura.

Autoimmune thrombotic thrombocytopenic purpura (iTTP) is a life-threatening, relapsing disease in which an acquired deficiency of the enzyme ADAMTS13 leads to generalised microvascular thrombosis. Survivors have a high prevalence of depression and impaired cognitive function. The aim of this study was to determine whether life circumstances and personality have an influence on the development and severity of depression and anxiety in iTTP patients and how they impact the quality of life. With validated questionnaires, we examined the prevalence of depression and anxiety symptoms in 104 iTTP patients, as well as parameters of subjective cognitive deficits, quality of life, attitude to life and resilience. iTTP patients had significantly more depressive symptoms (p < 0.001), a tendency to have anxiety disorders (p = 0.035) and a significantly worse cognitive performance (p = 0.008) compared to the controls. Sex, age, physical activity and partnership status had no significant influence on depression, whereas the number of comorbidities did. Lower scores of resilience, attitude to life and quality of life were reported by patients compared to controls. iTTP patients had a high prevalence of depression and anxiety, as well as a more negative attitude to life and low resilience. Resilience correlated negatively with the severity of the depression. Furthermore, quality of life and cognitive performance were significantly reduced.

[Asymmetric dimethylarginine (ADMA) in retinal vein occlusion-Results from the Gutenberg RVO study]. / Asymmetrisches Dimethylarginin (ADMA) bei retinalen Venenverschlüssen ­ Ergebnisse aus der Gutenberg-RVO-Studie.

BACKGROUND: Asymmetric dimethylarginine (ADMA) is considered an independent cardiovascular risk factor (cvRF) and thus represents a potential new biomarker for retinal vein occlusion (RVO). METHODS: Overall, 92 patients with RVO and the same number of matched controls were included in the Gutenberg RVO study. All patients underwent a standardized examination for cvRF at the study center of the population-based Gutenberg health study (GHS) as well as ophthalmological examinations and intensive laboratory tests. This article presents a substudy of patients (≤65 years old) and the controls in whom ADMA was additionally determined by high performance liquid chromatography (HPLC) at baseline and 4-6 weeks later. RESULTS: Out of 44 patients with RVO 22 had central retinal vein occlusion (CRVO), 15 had branch retinal vein occlusion (BRVO) and 7 had hemiretinal vein occlusion (hemi-RVO). The ADMA levels were 0.383 ± 0.094 µM (mean ± standard deviation) in RVO patients at baseline and 0.380 ± 0.093 µM (p = 0.514, initial vs. follow-up) after the follow-up period versus 0.360 ± 0.077 µM (p = 0.175, controls vs. RVO) in controls (n = 44). Arterial hypertension was the most prevalent risk factor in 22 (50%) of the patients and in 11 (25%) of the controls (odds ratio, OR 2.77, 95% confidence interval, CI 0.97-7.95; p = 0.058). The ADMA values above the 95th percentile (>0.530 µM) were detected in 4 patients with RVO (9.1%) but not in any of the controls (p = 0.041, RVO vs. controls). CONCLUSION: Hypertension is the most important risk factor for RVO. Due to the high number of hypertensive patients in the cohort, the relevance of ADMA as an independent risk factor could neither be confirmed nor disproved.

No Evidence for Classic Thrombotic Microangiopathy in COVID-19.

BACKGROUND: Coronavirus disease-2019 (COVID-19) triggers systemic infection with involvement of the respiratory tract. There are some patients developing haemostatic abnormalities during their infection with a considerably increased risk of death. MATERIALS AND METHODS: Patients (n = 85) with SARS-CoV-2 infection attending the University Medical Center, Mainz, from 3 March to 15 May 2020 were retrospectively included in this study. Data regarding demography, clinical features, treatment and laboratory parameters were analyzed. Twenty patients were excluded for assessment of disseminated intravascular coagulation (DIC) and thrombotic microangiopathy (TMA) due to lack of laboratory data. RESULTS: COVID-19 patients (n = 65) were investigated, 19 with uncomplicated, 29 with complicated, and 17 with critical course; nine (13.8%) died. Seven patients showed overt DIC according to the ISTH criteria. The fibrinogen levels dropped significantly in these patients, although not below 100 mg/dl. Hallmarks of TMA, such as thrombocytopenia and microangiopathic haemolytic anaemia, were not detected in any of our COVID-19 patients. ADAMTS13 activity was mildly to moderately reduced in 4/22 patients, all having strongly elevated procalcitonin levels. CONCLUSION: DIC occurred in 7/65 COVID-19 patients but fibrinogen and platelet consumption were compensated in almost all. ADAMTS13 assays excluded TTP and hallmarks of classic TMA were absent in all investigated patients. We hypothesize that the lacking erythrocyte fragmentation and only mild platelet consumption in severe COVID-19 are due to a microangiopathy predominantly localized to the alveolar microcirculation with a low blood pressure gradient.

Acquired haemophilia caused by non-haemophilic factor VIII gene variants.

The aetiology of anti-factor VIII (FVIII) autoantibody formation in acquired haemophilia remains unknown. We hypothesised that encounter of antigenically different, allogeneic FVIII may challenge inhibitor formation after presentation on MHC class II. Eighteen consecutive cases with acquired haemophilia were enrolled (nine females, nine males). A control group comprised 50 male and 50 female healthy blood donors. The coding region of the FVIII gene and the HLA-DRB1 genotype were studied. The presentation of foreign FVIII variants on the patient's MHC class II alleles was predicted using SYFPEITHI algorithm. A rare FVIII variant (E2004K) was found in one patient with acquired haemophilia after massive transfusion; the 2004 K allele was predicted to be presented on the patient's HLA-DRB1*0101. Moreover, distribution of a polymorphism (D1241E) was significantly skewed comparing patients and controls. Three of three patients with transfusion-associated disease carried 1241D in homozygous or hemizygous form and were predicted to present 1241E (foreign), but not 1241D (self), on their HLA-DRB1*0301. Therefore, encounter of 1241E may result in the presentation of a new T cell epitope in these patients. The same conditions were not found in any patient with acquired haemophilia of other causes. The expected frequency in the general Caucasoid population undergoing transfusion is 3% to 4%. In conclusion, encounter of variant allogeneic FVIII presented on a suitable MHC background could be a risk factor for inhibitor formation.

Mutations in VKORC1 cause warfarin resistance and multiple coagulation factor deficiency type 2.

Coumarin derivatives such as warfarin represent the therapy of choice for the long-term treatment and prevention of thromboembolic events. Coumarins target blood coagulation by inhibiting the vitamin K epoxide reductase multiprotein complex (VKOR). This complex recycles vitamin K 2,3-epoxide to vitamin K hydroquinone, a cofactor that is essential for the post-translational gamma-carboxylation of several blood coagulation factors. Despite extensive efforts, the components of the VKOR complex have not been identified. The complex has been proposed to be involved in two heritable human diseases: combined deficiency of vitamin-K-dependent clotting factors type 2 (VKCFD2; Online Mendelian Inheritance in Man (OMIM) 607473), and resistance to coumarin-type anticoagulant drugs (warfarin resistance, WR; OMIM 122700). Here we identify, by using linkage information from three species, the gene vitamin K epoxide reductase complex subunit 1 (VKORC1), which encodes a small transmembrane protein of the endoplasmic reticulum. VKORC1 contains missense mutations in both human disorders and in a warfarin-resistant rat strain. Overexpression of wild-type VKORC1, but not VKORC1 carrying the VKCFD2 mutation, leads to a marked increase in VKOR activity, which is sensitive to warfarin inhibition.

Selective thrombophilia screening of patients with nonarteritic anterior ischemic optic neuropathy.

BACKGROUND: To date, the question whether there is a relationship between thrombophilic disorders and the development of nonarteritic ischemic optic neuropathy (NAION) remains controversial. We sought to investigate the prevalence of various coagulation defects among NAION patients <65 years of age, and to provide clinical guidelines for a selective thrombophilia screening. METHODS: A cohort of 35 patients <65 years of age with NAION and 70 controls matched for age and sex were prospectively screened for thrombophilic risk factors. RESULTS: Overall, thrombophilic defects were found to be present in 18 of 35 patients (51.4%) and in 12 of 70 (17.1%) controls (P = 0.0005). The most frequent coagulation disorders were increased levels of factor VIII (P = 0.015) and lipoprotein (a) (P = 0.005). Patients without cardiovascular risk factors had a statistically significant higher frequency of coagulation disorders than patients with these risk factors (P = 0.0059). There was a strong association of coagulation disorders and a personal or family history of thromboembolism (P = 0.028). Moreover, we determined the age of

Retinal vein occlusion and low-dose fibrinolytic therapy (R.O.L.F.): a prospective, randomized, controlled multicenter study of low-dose recombinant tissue plasminogen activator versus hemodilution in retinal vein occlusion.

PURPOSE: To investigate the efficacy of intravenous thrombolysis with low-dose recombinant tissue plasminogen activator (rt-PA) in recent-onset central retinal vein occlusion (CRVO) or branch retinal vein occlusion. METHODS: This was a prospective, randomized, controlled multicenter trial in patients with CRVO or branch retinal vein occlusion, best-corrected visual acuity < or =20/50, and onset of symptoms within 11 days before treatment. In each group, patients were randomized to either hemodilution or thrombolysis with 50 mg of rt-PA with concomitant intravenous heparinization. The primary clinical outcome measure was improvement in best-corrected visual acuity from baseline at 1 year. RESULTS: Fifty-two subjects were enrolled in the study. Patients with CRVO (n = 41) who were treated with rt-PA exhibited a significant improvement in best-corrected visual acuity compared with those who received hemodilution (P < 0.0001). At 1-year follow-up, the proportion of eyes with CRVO achieving an improvement in visual acuity of three or more lines was 45% after treatment with rt-PA and 21% after hemodilution therapy. The median final best-corrected visual acuity among CRVO patients given rt-PA was 20/60 (light perception, 20/15) compared with 20/400 (light perception, 20/20) in the hemodilution group. There were no significant differences among patients with branch retinal vein occlusion (n = 11). We observed no serious adverse events. No significant differences were found regarding the development of ocular neovascularization. CONCLUSION: Treatment with intravenous low-dose rt-PA improved visual outcome in CRVO. Thrombolysis was not associated with a lower risk of ocular neovascularization, indicating that the mechanisms involved in this process occur at an early stage.

Hypertension and multiple cardiovascular risk factors increase the risk for retinal vein occlusions: results from the Gutenberg Retinal Vein Occlusion Study.

OBJECTIVE: Although several risk factors for retinal vein occlusion (RVO) are known, what triggers RVO is unclear in many cases. We aimed to evaluate the relevance of multiple risk factors in patients with RVO. METHODS: The Gutenberg RVO Study is an observational case-control study that assessed thrombophilic, cardiovascular, ophthalmic, and drug-related risk factors in participants with RVO and the same number of matched controls. Conditional logistic regression analysis was chosen to estimate the risk of RVO due to several risk factors. RESULTS: Of 92 patients with RVO, 46 (50%) had central RVO, 31 (33.7%) had branch RVO, and 15 (16.3) had hemi-RVO. Systemic hypertension was associated with RVO [any RVO: odds ratio (OR): 1.81; 95% confidence interval (CI): 1.14-2.88; branch RVO: OR: 2.56; 95% CI: 1.08-6.10]. The most frequent combinations of risk factors were hypertension with dyslipidemia (33 of 92, 35.9%) and hyperhomocysteinemia and high levels of factor VIII (10 of 92, 10.9%). An increase in the risk sum score by one additional risk factor corresponded to ORs of 1.74 (95% CI: 1.31-2.32) for cardiovascular risk factors, 1.38 (95% CI: 1.04-1.82) for thrombophilic risk factors, and 1.43 (95% CI: 1.20-1.70) for the total number of risk factors for RVO. CONCLUSION: Cardiovascular risk factors are more important than other risk factors for the presence of RVO. The risk of RVO increased by approximately 40% with any additional risk factor and by 70% with any additional cardiovascular risk factor.

Procoagulant activity during viral infections.

The abundance of evidence suggest that inflammation of immune and non-immune cells may lead to an imbalance of the pro- and anti-coagulant state during viral infections. During systemic infections, the endothelium plays a critical role in regulating hemostasis, and severe imbalances of endothelial function and activation can contribute to organ failure. Viral infections may elevate plasma levels of procoagulant markers such as TAT and D-dimer TF-positive MPs as well as von Willebrand factor (vWF). Although multiple clinical studies are showing the association of viral infection and increased prothrombotic risk, the pathological mechanisms have not been fully identified for most viral infections. Viral infection mediated TLRs activation is both cell type- and species-specific and explains the difficulties in correlating murine model data with the human data. In this review, we briefly discuss the TF-dependent coagulation activation, Toll-like receptors (TLRs) signaling during viral infections, and their contributions to the procoagulant response.

Relapse Rate in Survivors of Acute Autoimmune Thrombotic Thrombocytopenic Purpura Treated with or without Rituximab.

BACKGROUND: Autoimmune thrombotic thrombocytopenic purpura (iTTP) is caused by autoantibody-mediated severe a disintegrin and metalloprotease with thrombospondin type 1 repeats, member 13 (ADAMTS13) deficiency leading to micro-angiopathic haemolytic anaemia (MAHA) and thrombocytopenia with organ damage. Patients survive with plasma exchange (PEX), fresh frozen plasma replacement and corticosteroid treatment. Anti-CD20 monoclonal antibody rituximab is increasingly used in patients resistant to conventional PEX or relapsing after an acute bout. OBJECTIVE: This retrospective observational study focused on the relapse rate and possible influencing factors including treatment with rituximab first introduced in 2003. PATIENTS AND METHODS: Seventy patients treated between January 2003 and November 2014 were evaluated. Number, duration, clinical manifestations, laboratory data and treatment of acute episodes were documented. Diagnostic criteria of acute iTTP were thrombocytopenia, MAHA, increased lactate dehydrogenase and severe ADAMTS13 deficiency. RESULTS: Fifty-four female and 16 male patients had a total of 224 acute episodes over a median observation period of 8.3 years. The relapse rate was 2.6% per month, for women 2.4% and for men 3.5% per month. Since 2003, 17 patients with a first iTTP episode were treated with rituximab, whereas 28 were not. There was a trend towards lower relapse rates after rituximab treatment over the ensuing years. However, this was statistically not significant. CONCLUSION: This analysis does not show a significant reduction of acute iTTP relapses by rituximab given during an acute bout. Initial episodes are characterized by more severe clinical signs compared with the less severe relapses. Furthermore, men suffer significantly more frequent and considerably more serious acute relapses.

Author Correction: ADAMTS-13 regulates neutrophil recruitment in a mouse model of invasive pulmonary aspergillosis.

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has not been fixed in the paper.

Addition of rituximab to standard therapy improves response rate and progression-free survival in relapsed or refractory thrombotic thrombocytopenic purpura and autoimmune haemolytic anaemia.

Treatment of relapsed or refractory autoimmune mediated haemolytic syndromes, such as autoimmune haemolytic anaemia (AIHA) and thrombotic thrombocytopenic purpura (TTP), represents a therapeutic challenge. Here we report on our experience with the monoclonal anti-CD20 antibody rituximab (R) compared to standard treatment in these diseases. Patients with non-familial TTP or AIHA and no underlying malignancy were included in our analysis. Safety and efficacy of R-treatment were compared to results obtained in standard treatment approaches. Altogether, 27 patients were analyzed, comprising 15 patients with TTP and 12 patients with AIHA. The patients' average age at the time of diagnosis was 54 years. Eleven patients received antibody treatment (8 TTP, 3 AIHA). No acute or late WHO grade III/IV toxicity associated with rituximab was noted. With standard therapy, the overall response rate (ORR) was 66.7% for AIHA and 65.8% for TTP, respectively. For the R-containing regimens the ORR was 100%. In patients with TTP, median progression free survival (PFS) with R-treatment was 3.8 years, as compared to 0.1 years in the standard-treatment group. In patients with AIHA median PFS was not reached for R-containing treatment; all patients are in sustained remissions with a median follow up of 12.5 months. In the absence of prospective trials, our data underline the safety and efficacy of rituximab in relapsed and refractory autoimmune anaemias with favourable response rates and promising long-term progression-free survival. Therefore, prospective clinical trials evaluating rituximab as salvage- and first-line-therapy are clearly warranted.

ADAMTS-13 regulates neutrophil recruitment in a mouse model of invasive pulmonary aspergillosis.

Von Willebrand factor (VWF) is secreted as an acute phase protein during inflammation. ADAMTS-13 regulates the size and prothrombotic activity of VWF by it's specific proteolytic activity. To determine the relevance of this regulatory pathway for the innate inflammatory response by polymorphonuclear neutrophils (PMN), we employed a mouse model of invasive pulmonary aspergillosis (IPA) where PMN functionality is crucial for fungal clearance and survival. IPA was induced by intratracheal application of Aspergillus fumigatus (A. fumigatus) conidia in wildtype (129/Sv/Pas) or ADAMTS-13 deficient (Adamts13 -/-) mice. While neutropenic mice developed lethal IPA, all wildtype mice survived the infection. In contrast to wildtype or VWF deficient mice, Adamts13 -/- mice displayed more severe signs of disease with a lethal course in 24% with an increased fungal burden and signs of acute lung injury. Histology sections demonstrated a more pronounced perivascular leukocyte infiltration in support of a dysregulated inflammatory response in Adamts13 -/- mice. Importantly, we observed no general defect in the activation of neutrophil functions in response to conidia or hyphae in vitro. Therefore, we conclude that the proteolytic regulation of VWF by ADAMTS-13 or ADAMTS-13 by itself is an important mechanism to control PMN recruitment in acute inflammatory processes, such as fungal pneumonias.

Mice deficient in the anti-haemophilic coagulation factor VIII show increased von Willebrand factor plasma levels.

Von Willebrand factor (VWF) is the carrier protein of the anti-haemophilic Factor VIII (FVIII) in plasma. It has been reported that the infusion of FVIII concentrate in haemophilia A patients results in lowered VWF plasma levels. However, the impact of F8-deficiency on VWF plasma levels in F8-/y mice is unresolved. In order to avoid confounding variables, we back-crossed F8-deficient mice onto a pure C57BL/6J background and analysed VWF plasma concentrations relative to C57BL/6J WT (F8+/y) littermate controls. F8-/y mice showed strongly elevated VWF plasma concentrations and signs of hepatic inflammation, as indicated by increased TNF-α, CD45, and TLR4 transcripts and by elevated macrophage counts in the liver. Furthermore, immunohistochemistry showed that expression of VWF antigen was significantly enhanced in the hepatic endothelium of F8-/y mice, most likely resulting from increased macrophage recruitment. There were no signs of liver damage, as judged by glutamate-pyruvate-transaminase (GPT) and glutamate-oxalacetate-transaminase (GOT) in the plasma and no signs of systemic inflammation, as white blood cell subsets were unchanged. As expected, impaired haemostasis was reflected by joint bleeding, prolonged in vitro clotting time and decreased platelet-dependent thrombin generation. Our results point towards a novel role of FVIII, synthesized by the liver endothelium, in the control of hepatic low-grade inflammation and VWF plasma levels.

Retinal vein occlusion associated with antithrombin deficiency secondary to a novel G9840C missense mutation.

OBJECTIVE: To describe a novel missense mutation in the antithrombin gene associated with antithrombin deficiency type I in a 40-year-old man with retinal vein occlusion. DESIGN: Investigational case report. RESULTS: Ophthalmoscopy of the right eye showed hemicentral retinal vein occlusion. The patient's medical history was negative for glaucoma or cardiovascular risk factors. Screening for thrombophilic disorders revealed antithrombin deficiency type I. Based on a genetic analysis, a novel missense mutation of a transition of guanosine to cytosine at nucleotide position 9840 was detected, predicting the replacement of aspartic acid by histidine encoded by codon 366 (D366H) in exon 5. CONCLUSIONS: Selective screening may be helpful in identifying patients with retinal vein occlusion with thrombophilic defects. When ordering laboratory tests in patients with retinal vein occlusion, antithrombin deficiency type I should be considered in the differential diagnosis. CLINICAL RELEVANCE: Our results contribute to a better understanding of the molecular bases of antithrombin deficiency, adding a novel entry for the molecular defects causing antithrombin deficiency type I. Moreover, the identification of this thrombophilic disorder in retinal vein occlusion may be relevant to the issue of the initiation and duration of oral anticoagulant therapy.

Recurrence rate after a first venous thrombosis in patients with familial thrombophilia.

OBJECTIVE: Few comprehensive data are available on the recurrence rate of venous thrombosis in carriers of thrombophilic defects from thrombophilic families. We prospectively determined the recurrence rate after a first venous thrombotic event in patients with familial thrombophilia attributable to factor V Leiden or deficiencies of protein C, S, or antithrombin. METHODS AND RESULTS: Data were gathered during follow-up on the occurrence of risk situations, anticoagulation treatment, and events (eg, venous thrombosis, hemorrhage). Over a mean follow-up period of 5.6 years, 44 of the 180 patients with familial thrombophilia who did not use long-term anticoagulation experienced a recurrent venous thromboembolic event (5.0%/year; 95% CI 3.6 to 6.7) compared with 7 of the 124 patients on long-term anticoagulation (1.1%/year; 95% CI 0.4 to 2.2). Spontaneous events occurred less often in patients on long-term anticoagulation (57%) than in patients without long-term anticoagulation (75%). The highest recurrence rate was found among men with a deficiency in natural anticoagulants or multiple defects and women with antithrombin deficiency. Although long-term anticoagulation treatment decreased the incidence of recurrent events by 80%, it also resulted in a risk of major hemorrhage of 0.8% per year. CONCLUSIONS: Extra care after a first event is required for men with a deficiency in natural anticoagulants or multiple defects and women with antithrombin deficiency.