Homocysteine, MTHFR C677T gene polymorphism, folic acid and vitamin B 12 in patients with retinal vein occlusion

BACKGROUND: Many available data have suggested that hyperhomocysteinaemia, an established independent risk factor for thrombosis (arterial and venous), may be associated with an increased risk of retinal vein occlusion (RVO). AIM OF THE STUDY: To evaluate homocysteine metabolism in consecutive caucasian patients affected by RVO from Northern Italy. PATIENTS AND METHODS: 69 consecutive patients from Northern Italy (mean age 64.1 ± 14.6 yy) with recent RVO, were tested for plasma levels of homocysteine (tHcy: fasting and after loading with methionine), cyanocobalamine and folic acid levels (CMIA-Abbot) and looking for MTHFR C677T mutation (Light Cycler-Roche) and compared to 50 volunteers, enrolled as a control group. RESULTS: Fasting levels of tHcy were significantly higher in patients than in controls: mean value 14.7 ± 7.7 vs 10.2 ± 8 nmol/ml. Post load levels were also significantly higher: mean value 42.7 ± 23.7 vs 30.4 ± 13.3 nmol/ml; Total homocysteine increase was also evaluated (i.e. Δ-tHcy) after methionine load and was also significantly higher in patients compared to control subjects: mean Δ-tHcy 27.8 ± 21.5 vs 21.0 ± 16 nmol/ml (normal value < 25 nmol/ml). Furthermore, patients affected by RVO show low folic acid and/or vitamin B12 levels, although differences with control group did not reach statistical significance. Heterozygous and homozygous MTHFR mutation were respectively in study group 46% and 29% vs control group 56% and 4%. CONCLUSION: our data confirm that hyperhomocysteinaemia is a risk factor for RVO, and also that TT genotype of MTHFR C677T is more frequently associated with RVO: if the mutation per se is a risk factor for RVO remains an open question to be confirmed because another study from US did not reveal this aspect. Hyperomocysteinemia is modifiable risk factor for thrombotic diseases. Therefore, a screening for tHcy plasma levels in patients with recent retinal vein occlusion could allow to identify patients who might benefit from supplementation with vitamins and normalization of homocysteine levels, in fasting and after methionine load

low molecular weight heparin in women with repeated implantation failure

Implantation failure is common in assisted reproduction techniques (ART). The role of low-molecular-weight heparin (LMWH) is a matter of debate as a potential factor to improve implantation. Aim: To evaluate the pregnancy rate in patients with or without heparin administration. Materials & methods: We performed a retrospective observational analysis of patients with at least two IVF/intracytoplasmic sperm injection cycles with implantation failure, screened for inherited thrombophilia and submitted to further ART cycles with or without administration of LMWH. A total of 265 patients fulfilled the enrollment criteria. Of these 149 (56%) were primary infertile and 116 (44%) were secondary infertile. Their mean age was 36.3 ± 3.6 years. We analyzed basal FSH, smoking habit, gene variants for inherited thrombophilia (i.e., MTHFR C677T, prothrombin G202A10G and Factor V Leiden). The patients underwent 569 new ART cycles: 512 (90%) without and 57 (10%) with LMWH. Results: In total 105 clinical pregnancies were ..

Venous Thromboembolism and Its Association with COVID-19: Still an Open Debate

Asreported by the World Health Organization, a novel coronavirus (COVID-19) was identified as the causative virus of new viral pneumonia of unknown etiology by Chinese authorities on 7 January 2020. The virus was named COVID-19 and because of its ability to cause severe acute respiratory syndrome (i.e., SARS) this infection has also been defined as SARS-CoV2.Furthermore, an association between COVID-19 infection and venous thromboembolism has been reported in several series around the world.For this reason, methods used to improve diagnostic tools, pharmacological thromboprophylaxis and type of anticoagulants are discussed in this expert opinion

Acute limb ischemia in a patient with pre-fibrotic myelofibrosis complicated by heparin-induced thrombocytopenia and thrombosis - case report and systematic review of dabigatran use

A 49-year-old man was diagnosed with pre-fibrotic myelofibrosis after acute left lower-limb ischemia requiring amputation and portal vein thrombosis. After surgery he developed heparin-induced thrombocytopenia (HIT) with venous thromboembolism, successfully treated with argatroban followed by dabigatran. Our systematic review of the literature supports the use of dabigatran for suspected HIT