Loop-mediated isothermal amplification (LAMP)-based method for detecting factor V Leiden and factor II G20210A common variants.

Automated methodologies allowing for rapid detection of Factor V Leiden and Factor II G20210A variants are desirable, due to a high number of tested patients. Here, we report a preliminary validation of a CE-marked in vitro diagnostic (IVD) certified method for simultaneous detection of Factor V Leiden and Factor II G20210A variants on whole blood samples. The novel method is based on Loop-mediated isothermal AMPlification (LAMP) applied for a duplex detection of Factor V Leiden and Factor II G20210A variants without requiring prior DNA extraction, whereas the routine one is a TaqMan SNP genotyping targeting genomic DNA. We tested routine patients for both variants using novel and current methods and estimated concordance rate. Patients were tested under similar laboratory procedures. One hundred and eight patients referred for the thrombophilia testing in the period between 9th December 2019 to 27th February 2020 represented the study population. We routinely identified for the Factor V Leiden variant 163 wild-type, 17 heterozygotes and no homozygote. Concerning the Factor II G20210A variant, we identified 170 wild-type, nine heterozygotes and one homozygous carrier. Two heterozygotes carried both variants (double heterozygotes). The LAMP method showed a 100% concordance rate, detecting rightly all genotypes. The LAMP for a duplex detection of common thrombophilia variants shows analytic performances as good as those of the standard method.

Anemone study: prevalence of risk factors for superficial vein thrombosis in a large Italian population of blood donors.

Knowledge of the distribution of risk factors for superficial thrombosis (SVT) in low-risk population is fundamental to improve the prevention of the disease in each individual and high-risk settings of patients. Exact frequency data for the low-risk population are scarce, but could be useful for optimal use of prophylactic strategies against venous thrombosis. Blood donors represent a low-risk population, because are healthier than the general population. The objective of this study was to assess the prevalence of vein thrombosis, particularly SVT, and associated risk factors in a low-risk population such as blood donors. In this multicentre cross-sectional study, donors from six Italian blood banks responded to a self-administered questionnaire. The enrolment lasted from 1st June 2017 to 30th July 2018. History of vein thrombosis was referred by 89 (0.76%) individuals, (49 men) with an age-dependent effect. The prevalence reached 2.9% in women and 0.8% in men aged ≥ 49 years, with a significant difference only for women. After controlling for potential confounders, a significant and independent association was found between a history of vein thrombosis and age (OR: 1.03, 95%CI 1.01-1.05), varicose veins (OR: 15.8, 95%CI 7.7-32.6), plaster cast/bed rest (OR: 2.3, 95% CI 1.0-5.3) and transfusion (OR: 5.1, 95% CI 1.3-19.5). This study shows that low-risk individuals share the same risk factors for SVT as patients in secondary care. It also suggests that transfusion confers an increased risk of SVT in healthy population.

Venous thromboembolism in assisted reproductive technologies: comparison between unsuccessful versus successful cycles in an Italian cohort.

Pregnancies after assisted reproductive technologies (ART) have been associated with an increased risk of venous thromboembolism (VTE). On the contrary, the magnitude of this risk in unsuccessful ART cycles (not resulting in a clinical pregnancy) has not yet been clearly defined. In this study, we evaluated the incidence of VTE in unsuccessful cycles and compared it with that recorded in successful cycles in the same study population. From a cohort of 998 women consecutively referred by local Fertility Clinics to our Atherosclerosis and Thrombosis Unit (April 2002-July 2011), we identified and included women with at least one cycle of ovarian stimulation and a negative history for VTE. Overall, 661 women undergone 1518 unsuccessful and 318 successful cycles of ovarian stimulation, respectively, were analysed. VTE events occurred in 2/1518 (1.3‰) unsuccessful cycles compared with 3/318 (9.4‰) successful cycles, (Two-tailed Fisher exact test, p = 0.04, OR 0.14, 95% CI 0.02-1.02). Both cases observed in unsuccessful cycles were isolated pulmonary embolism occurred after OHSS; no antithrombotic prophylaxis had been prescribed. At logistic regression analysis, the occurrence of successful cycle and BMI were significantly and independently associated with the occurrence of VTE with an OR of 13.94 (95% CI 1.41-137.45) and 1.23 (95% CI 1.01-1.49), respectively. VTE incidence is significantly lower in unsuccessful cycles as compared to that of successful ones. However, although rare, thrombotic risk during ovarian stimulation cannot be excluded and, when it occurs, can be life-threatening. Therefore, particular attention should be paid to these women, independently of ART outcome.

Pregnancy-related venous thrombosis: comparison between spontaneous and ART conception in an Italian cohort.

OBJECTIVE: To evaluate in an Italian cohort the incidence of venous thromboembolic events (VTE) in pregnancies after assisted reproductive technologies (ART). SETTING: Thrombosis and Haemostasis Unit at I.R.C.C.S. 'Casa Sollievo della Sofferenza', S. Giovanni Rotondo. PARTICIPANTS: A prospective cohort of 998 women advised to undergo ART was referred by local fertility clinics from April 2002 to July 2011. Follow-up information was obtained during the check-up and/or by phone interviews. In a cohort of women who consecutively gave birth (n=3339) after spontaneous conception in our Institution, information on the diagnoses of pregnancy-related venous thromboses was obtained by linkage to a patient administrative register. PRIMARY AND SECONDARY OUTCOME MEASURES: We calculated the incidence of VTE and superficial venous thrombosis in successful ART cycles and compared it with that of the general population conceiving spontaneously. RESULTS: Overall, 684 ART cycles were carried out by 234 women, who achieved a clinical pregnancy; in case of more than one successful cycle, only the first pregnancy was considered. Three vein thromboses (two VTE and one superficial vein thrombosis) were recorded. An antithrombotic prophylaxis with LMWH alone or combined with low-dose aspirin was prescribed in 23/234 (9.8%) women. In the reference cohort of 3339 women, a total of 11 vein thromboses were observed: six VTE and five SVT. The two-tailed Fisher exact test showed a trend towards statistical significance (p: 0.06, OR: 3.9, 95% CI 0.87 to 15.3). After the exclusion of superficial thromboses in both the groups, we found that the incidence of VTE in our population of women who had undergone ART was 2/234 pregnancies (8.5 ‰), whereas that in our reference population was 6/3339 (1.8 ‰) (p: 0.09). CONCLUSIONS: Our data show a slightly higher incidence of vein thromboses in pregnancies after ART than in those after natural conception.

Sex modulation of the occurrence of jak2 v617f mutation in patients with splanchnic venous thrombosis.

BACKGROUND: The JAK2 V617F mutation is an independent risk factor for MPN and SVT. Gender-related differences in MPN distribution have been reported and, recently, variability in the JAK2 V617F allele burden between sexes has been suggested. We wondered whether gender would modulate the role of the JAK2 V617F mutation as susceptibility risk factor for SVT. MATERIALS AND METHODS: In 180 patients presenting with SVT, medical history was collected. The presence of the JAK2 V617F mutation and 46/1 haplotype was determined by polymerase chain reaction followed by TaqMan SNP genotyping assays. RESULTS: Among patients with SVT, 43 (23.9%; 95%-CI: 18.2-30.7) carried the JAK2 V617F mutation. The JAK2 V617F mutation was found more frequently in women (29/95: 30.5%; 95%-CI: 22.1-40.4) than in men (14/85: 16.5%; 95%-CI: 10.0-25.9; OR: 2.2; 95%-CI: 1.1-4.5). The distribution of 46/1 haplotype frequencies did not differ significantly between men and women. In women carrying the rs12343867 CC genotype, the frequency observed for the occurrence of the V617F mutation was significantly higher than that observed in those not carrying (60.0% [95% CI: 31.2-83.3] vs. 26.8% [95% CI: 18.4-37.4]; OR: 4.1; 95%-CI: 1.1-14.9). In men, a similar prevalence was found among carriers of the rs12343867 CC genotype (16.7% [95% CI: 3.5-46.0]) and in non carriers (16.4% [95% CI: 9.3-27.2]). The V617F allele burden was unrelated to clinical characteristics and significantly higher in carriers of the rs12343867 CC genotype. CONCLUSIONS: Present findings suggest that, in patients presenting with SVT, the JAK2 V617F mutation is frequently found in women and, possibly by interacting with the 46/1 haplotype, may represent a gender-related susceptibility allele for SVT.

Annexin V expression in human placenta is influenced by the carriership of the common haplotype M2.

In a group of placentas from patients with preeclampsia or fetal growth restriction, reduced annexin V gene expression in those carrying the M2 haplotype was observed. This is the first "ex vivo" demonstration that annexin V gene expression in placentas is dependent on the M2 haplotype.

Gain-of-function gene mutations and venous thromboembolism: distinct roles in different clinical settings.

OBJECTIVE: To calculate the prevalence of common gain of function gene mutations in patients with different clinical manifestations of venous thromboembolism. DESIGN AND SETTING: Case-control study in two hospitals in Italy. PARTICIPANTS: 387 patients with venous thromboembolism and 286 controls. MAIN MEASURES: Factor V (FV) Leiden, factor II (FII) A20210 and JAK2 V617F mutations. RESULTS: Among patients with deep vein thrombosis in one leg, 23 (20.9%) carried FV Leiden and FII A20210 mutations. Similar figures were observed in patients with cerebral vein thrombosis (CVT; n = 9; 20.0%) and in patients presenting with splanchnic vein thrombosis (SVT; n = 26; 18.7%). A lower prevalence was obtained in patients with retinal vein thrombosis (n = 11; 11.8%). The JAK2 F617 mutant allele was found in 27 (21.1%) patients with SVT, but in none of the patients presenting with a thrombotic event from different districts. 13 of the 27 JAK2 V617F-positive subjects with SVT were previously known to have a myeloproliferative disease (MPD). Three other patients had a diagnosis of MPD after the occurrence of the thrombotic event. CONCLUSION: Carriership of FV Leiden or FII A20210 mutations identifies an at-risk condition for venous thrombosis in the lower extremities, SVT or CVT. In patients with SVT, screening for the JAK2 V617F mutation may be useful in recognising patients who should be carefully observed for the subsequent development of overt MPD. Thus, genetic tests may play a different role, various clinical manifestations of venous thromboembolism being associated with distinct risk profiles.

Hyperhomocysteinaemia in chronic liver diseases: role of disease stage, vitamin status and methylenetetrahydrofolate reductase genetics.

BACKGROUND/AIMS: The liver plays a key role in sulphur aminoacid metabolism hence, homocysteine metabolism may be impaired in chronic liver diseases. The aim of this study was to investigate, in patients affected by chronic liver diseases, (1) the prevalence of hyperhomocysteinaemia and (2) the role of its determinants such as the stage and the aetiology of disease, vitamin status, genetic documented alterations (methylenetetrahydrofolate reductase deficiency) and presence/absence of documented malignant evolution (hepatocellular carcinoma). MATERIAL AND METHODS: One hundred and thirty patients with chronic liver disease (34 with chronic active hepatitis, 12 with fatty liver and 88 with liver cirrhosis) and 50 healthy age-matched control subjects were included into the study. RESULTS: Hyperhomocysteinaemia was defined as homocysteine plasma levels greater than 12.6 micromol/l. Hyperhomocysteinaemia prevalence in liver cirrhosis group was 40.9%, significantly higher (all P<0.01) with respect to controls (12%), chronic active hepatitis (14.7%) and fatty liver (25%) groups and increased with Child-Pugh stage [Child A: 22.2%, Child B (50%); Child C (58.3%)]. In chronic-active hepatitis and liver cirrhosis, the prevalence of subjects with methylenetetrahydrofolate reductase C677-->T mutation (both as CT and as TT) and hyperhomocysteinaemia results in significantly higher levels with respect to controls. Methylenetetrahydrofolate reductase C677-->T mutation and disease stage showed to be the most important predictive factors of hyperhomocysteinaemia in liver cirrhosis whereas the influence of homocysteine-related vitamin status seems to have a secondary role. CONCLUSIONS: In conclusion hyperhomocysteinaemia is highly prevalent in liver cirrhosis but not in other chronic liver diseases; it may contribute to fibrogenesis and vascular complication of liver cirrhosis.