Diagnostic and prognostic value of factor VIII binding antibodies in acquired hemophilia A: data from the GTH-AH 01/2010 study.

UNLABELLED: Essentials Factor VIII (FVIII) binding IgG detected by ELISA could be an alternative to the Bethesda assay. We studied the performance of anti-FVIII IgG ELISA in patients with acquired hemophilia and controls. Anti-FVIII IgG > 99th percentile of controls was highly sensitive and specific. Patients with high anti-FVIII IgG have a lower chance of achieving remission. SUMMARY: Background Acquired hemophilia A is a severe bleeding disorder that requires fast and accurate diagnosis as it occurs often unexpectedly in previously healthy men and women of every age. The Nijmegen-modified Bethesda assay is the diagnostic reference standard for detecting neutralizing autoantibodies against factor VIII (FVIII), but is not widely available, not ideal for quantifying the complex type 2 inhibitors seen in acquired hemophilia, and suffers from high inter-laboratory variability. Objectives To assess the diagnostic and prognostic value of FVIII-binding antibodies as detected by ELISA compared with the Nijmegen Bethesda assay. Methods Samples from the time of first diagnosis and clinical data were available from 102 patients with acquired hemophilia enrolled in the prospective GTH-AH 01/2010 study. Controls (n = 102) were matched for gender and age. Diagnostic cut-offs were determined by receiver-operator curve analysis. The prognostic value was assessed in 92 of the 102 patients by Cox regression analysis of time to partial remission. Results Anti-FVIII IgG above the 99th percentile (> 15 arbitrary units per mL) revealed high sensitivity and specificity (both 0.99; 95% confidence interval, 0.95-1.0) for diagnosing acquired hemophilia. The likelihood of achieving partial remission was related to anti-FVIII IgG concentration (< 300 arbitrary units, 1.0; 300-1050, 0.65; > 1050, 0.39). The Bethesda titer was only associated with the likelihood of partial remission when analyzed in the central laboratory, but not when data from local GTH study sites were used. Conclusion Although the Nijmegen-modified Bethesda assay is the reference standard for demonstrating neutralizing antibodies, the detection of FVIII-binding antibodies by ELISA is similarly sensitive and specific for diagnosing acquired hemophilia. In addition, anti-FVIII IgG may provide prognostic information.

[Perioperative conversion of oral anticoagulants to heparin (bridging) in ophthalmic medicine]. / Perioperative Umstellung von oralen Antikoagulanzien auf Heparin in der Augenheilkunde (Bridging).

Since topical anesthesia was introduced in ophthalmic surgery, anticoagulation therapy can often be used in patients with thromboembolic risk. But some surgical procedures with an increased risk for intraoperative bleeding necessitate changing a patient's Coumadin therapy to heparin. To reduce intraoperative bleeding and perioperative thromboembolic complications, ophthalmologists and referring general practitioners should cooperate closely.

Fluvastatin/fenofibrate vs. simvastatin/ezetimibe in patients with metabolic syndrome: different effects on LDL-profiles.

BACKGROUND: Patients with metabolic syndrome (MS) and type 2 diabetes (T2DM) show increased risk for coronary artery disease. Lipoprotein metabolism is characterized by elevated triglycerides (TG), low high-density lipoprotein cholesterol (HDL-C) and predominance of atherogenic small, dense low-density lipoprotein (sdLDL), while low-density lipoprotein (LDL) cholesterol is only slightly elevated. METHODS: Multicentre, randomized, open-label cross-over study investigating the effect of combination of fluvastatin/fenofibrate (80/200 mg) (F&F) on LDL-subfractions compared with combination of simvastatin/ezetimibe (20/10 mg) (S&E) in patients with MS/T2DM. RESULTS: Seventy-five patients were randomized, 69 completed the study and LDL-subfractions of 56 patients were analysed. Thirty-eight out of 56 patients (68%) showed a profile dominated by sdLDL. In these, TG and total cholesterol (TC) were elevated compared with non-sdLDL patients. In all patients, reduction of TC and LDL cholesterol (LDL-C) by S&E was stronger than by F&F. The increase of HDL-C was stronger with S&E in the non-sdLDL group, whereas in the sdLDL group, there was no difference between treatments. In non-sdLDL patients, there was no effect on TG or LDL-radius. However, in the sdLDL group, F&F was more effective in reducing TG and increased LDL radius, whereas S&E reduced LDL radius even further. CONCLUSIONS: S&E is more efficient in reducing TC and LDL-C. This is also true for HDL-C increase in non-sdLDL patients. However, in patients with sdLDL, F&F was more efficient in reducing TG and increasing LDL radius.

Genetic risk factors in young adults with 'cryptogenic' ischemic cerebrovascular disease.

Mutations such as factor V Leiden G1691A (FVL), prothrombin G20210A (FIIM), methylenetetrahydrofolate reductase (MTHFR) C677T, cystathionine beta-synthase (CBS) 844ins68 and endothelial cell protein C receptor (EPCR) 4031ins23 are risk factors for thromboembolism. To assess the role of these mutations in young adults with cerebral ischemia of otherwise undetermined etiology, 93 patients younger than 50 years old with thromboembolic strokes or transient ischemic attacks were studied. One hundred and eighty-six healthy age-matched and sex-matched blood donors served as controls. The FVL mutation was detected in 15/93 patients and 13/186 controls. After adjustment for smoking, arterial hypertension, and hyperlipidemia, the association of the FVL mutation with cerebral ischemia [odds ratio (OR), 3.19; 95% confidence interval (CI), 1.38-7.39] remained significant. One of 93 patients and 6/186 controls were carriers of FIIM (OR, 0.33; 95% CI, 0.04-2.75). We detected the MTHFR TT677 genotype in 9/93 patients and 26/186 controls (OR, 0.66; 95% CI, 0.30-1.47), a CBS 844ins68 mutation in 12/93 patients and 19/186 controls (OR, 1.30; 95% CI, 0.60-2.81), and an EPCR 4031ins23 mutation in 1/93 patients and in no control individual (P = 0.33). In conclusion, in younger adults the FVL mutation is a risk factor for cerebrovascular disease. FIIM, the MTHFR TT677 genotype and the CBS 844ins68 mutation did not contribute to the risk in this group of patients. The EPCR 4031ins23 mutation is very rare, its possible role needs further investigation.

The impact of dalteparin (Fragmin) on thrombin generation in pregnant women with venous thromboembolism: significance of the factor V Leiden mutation.

Hypercoagulability is observed in patients with inherited thrombophilia, e.g. factor V Leiden (FVL) mutation. Pregnancy represents a hypercoagulable state as well. This study addresses the effects of the FVL mutation on haemostatic activation during pregnancy as indicated by prothrombin fragments (F1+2). 233 pregnant women with no history of venous thromboembolism were studied. Additionally, two patient groups (25 pregnant FVL carriers and 36 pregnant women without thrombophilic diathesis) in whom low molecular weight heparin (dalteparin) was used prophylactically against rethrombosis were investigated. None of the women developed clinical signs of venous thromboembolism during pregnancy or after delivery. Untreated women exhibited substantial hypercoagulability. F1+2 levels were similar in FVL carriers and non-carriers (difference n. s.). After sufficient adjustment for anti-factor Xa activity (> or =0.15; < or =0.4 U/mL), heparinized women without any thrombophilic diathesis had significantly lower levels of F1+2 than untreated pregnant women. This was evident only in the first and second trimenon (p <0.001). F1+2 levels in heparinized FVL carriers were quite similar to the levels observed in untreated pregnant women, however. In conclusion, our data support the thesis that in comparison to asymptomatic patients, thrombin generation is exaggerated in symptomatic FVL carriers. Coagulation activation during pregnancy can be reduced by dalteparin.

Selective screening for the Factor V Leiden mutation: is it advisable prior to the prescription of oral contraceptives?

The cumulative thrombotic risk of Factor V (FV) Leiden and oral contraceptives (OC) recommends screening for the mutation. Assuming that a family history of thrombosis increases the patient's likelihood of bearing FV Leiden, a selective rather than universal screening would be performed. We studied the utility of a family history of thrombosis for screening of FV Leiden before prescription of OC and, furthermore, the utility of screening even if oral contraception is favoured. 101 patients who had their first and single thromboembolic event while using OC were interviewed. 609 women without any history of thromboembolism recruited by gynecologists completed a standard questionnaire. 101 of these women, age-matched and currently using OC, were selected for a case-control study. Regarding patients with previous thromboembolism, a family history in a first-degree relative had a positive predictive value (PPV) of only 14% for FV Leiden. A PPV of 12% was calculated by investigating the 609 thrombosis-free women. Inherited FV Leiden (odds ratio = 4.9) and acquired risk factors (odds ratio = 10.1) were both found to be the most prominent, but independent additional risks. Nevertheless, FV Leiden carriers, both heterozygotes and homozygotes, did not suffer earlier from thromboembolism than patients without the mutation. In conclusion, family history is an unreliable criterion to detect FV Leiden carriers. Screening for factor V Leiden can be worthwhile even if the advantages of oral contraception are higher assessed than the thrombotic risk. Affected women knowing about their additional risk could contribute to the prevention of thrombosis in risk situations.

PIP: The cumulative thrombotic risk of Factor V Leiden (FVL) and oral contraceptive (OC) use raises the possibility of either selective or universal screening for this mutation before OCs are prescribed. Family history of venous thromboembolism as a criterion to detect FVL carriers was evaluated in a case-control study of 101 women from Bavaria, Germany, who had their first and single thromboembolic event while using OCs and 101 healthy age-matched OC users. A questionnaire was administered to a broader group of 609 OC users without a history of thromboembolism. Analysis of the 609 women revealed a 7.4% prevalence of FVL, but no association between this mutation and a family history of thromboembolism. Among women with a previous thromboembolism, a family history in a first-degree relative had a positive predictive value of only 14% for FVL. The sensitivity of family history was under 50%. 35% of cases compared with 8% of controls carried the FVL mutation. The most significant independent risk factors of thromboembolism were inherited FVL (odds ratio, 4.9) and acquired risk factors--i.e., surgery, leg fractures, distortions, confinement to bed for more than 1 week, or a restricted sitting position more than 6 hours in the 4 weeks before the index date (odds ratio, 10.1). Both heterozygote and homozygote FVL carriers did not suffer earlier from thromboembolism than patients without the mutation. These findings indicate that family history is not an effective predictor of FVL. However, even if the advantages of OC use are greater than the thrombotic risk, screening for FVL may be indicated to permit high-risk women to take preventive action.