Search

Introduction. Despite proven clinical effect of clopidogrel, a considerable number of patients do not have an adequate response to this type of medication. Problems during therapy occur in the form of resistance, which is present in 11% of patients or bleeding that occurs in about 9% of patients. Pharmacogenomics studies demonstrated that variants of the CYP2C19 gene significantly influence the interindividual heterogenity of the clopidogrel response. The American Heart Association, US Food and Drug Administration and the European Medicines Agency, cite the CYP2C19 gene as a significant factor which influences patients response to clopidogrel. Further, it has been shown that the contribution of genetic and non-genetic factors affecting clopidogrel therapy may vary between patients from different populations, which justifies conducting population-specific studies. The aim. The aim of our study was to examine the significance of the CYP2C19*2 and the CYP2C19*17 variants in the individual response to clopidogrel, in Serbian patients. Methods. The study involved 108 patients with carotid artery stenosis who underwent endarterectomy and received clopidogrel for at least 30 days after the intervention. Also, 120 patients with myocardial infarction receiving clopidogrel after PCI (percutaneous coronary intervention) were included. Commercial tests were used for standard laboratory testing. Allelic discrimination was performed after Sanger sequencing. Results were analysed using statistical tests. Results. In patients undergoing endarterectomy CYP2C19*2 carriers had a higher risk for being clopidogrel low-responder in comparison with non-carriers (1.250, 95% CI 1.695–1.658, P<0.01). In the group of patients undergoing PCI, risk for reinfarction in patients who were carriers of CYP2C19*2 was higher compared to patients with wild type genotype (OR 5.355, 95% CI 0.955-31.08; P=0.038). Variant CYP2C19*17 showed no association with variations in response to clopidogrel therapy.

Background: The superiority of dabigatran has been well proven in the standard dosing regimen in prevention of stroke and systemic embolism in patients with non-valvular atrial fibrillation (NVAF) and extended venous thromboembolism (VTE) treatment. Dabigatran, an anticoagulant with a good safety profile, reduces intracranial bleeding in patients with atrial fibrillation and decreases major and clinically relevant non-major bleeding in acute VTE treatment. However, several important clinical issues are not fully covered by currently available directions with regard to dabigatran administration. The prominent one is reflected in the fact that dynamic impairment in renal function due to dehydratation may lead to haemorragic complications on the one hand, while on the other hand glomerular hyperfiltration may be a possible cause of dabigatran subdosing, hence reducing the drug's efficacy. Furthermore, limitations of the Cockcroft-Gault formula, considered a standard equation for assessing the renal function, may imply that other calculations are likely to obtain more accurate estimates of the kidney function in specific patient populations. Method and Conclusions: Although not routinely recommended, a possibility of monitoring dabigatran in special clinical settings adds to optimization of its dosage regimens, timely perioperative care and administration of urgently demanded thrombolytic therapy, therefore significantly improving this drug's safety profile. Despite the fact that dabigatran has fewer reported interactions with drugs, food constituents, and dietary supplements, certain interactions still remain, requiring considerable caution, notably in elderly, high bleeding risk patients, patients with decreased renal function and those on complex drug regimens. Additionally, upon approval of idarucizumab, an antidote to dabigatran solution, hitherto being a major safety concern, has been finally reached, which plays a vital role in life-threatening bleeding and emerg

Klopidogrel je antiagregacioni lek koji je sa aspirinom, u sklopu dvojne antiagregacione terapije, indikovan u stanjima koja nose rizik od ishemijskih događaja i tromboembolijskih komplikacija. Postoji velika interindividualna varijabilnost u odgovoru na klopidogrel. Značajan broj pacijenata kao posledicu neadekvatnog odgovora na terapiju može iskusiti različita neželjena dejstva. Kod oko 9% pacijenata koji su na terapiji klopidogrelom javlja se krvarenje kao neželjeni efekat. Ono samo po sebi može biti životno ugrožavajuće, a sekundarno može biti povezano sa pojavom ishemijskih događaja. Uzroci varijabilnosti u odgovoru na terapiju klopidogrelom, mogu biti kako stečeni, tako i posledica genetičkih faktora. Među genetičkim faktorima najznačajniji doprinos ima gen za enzim CYP2C19 koji je neophodan u procesu konverzije klopidogrela u aktivnu formu leka. Zbog toga su varijante CYP2C19 gena najčešće razmatrane u okviru farmakogenetike klopidogrela. Od posebnog kliničkog značaja su varijante rs4244285 (c.681G>A; CYP2C19*2) i rs4986893 (c.636G>A; CYP2C19*3), koje su povezane sa oslabljenim odgovorom na klopidogrel. Promotorska varijanta rs12248560 (c.-806C>T, CYP2C19*17) se dovodi u vezu sa pojačanim stepenom inhibicije trombocita i povišenim rizikom od krvarenja kod pacijenata na terapiji klopidogrelom. U fokusu ove studije bilo je ispitivanje uticaja CYP2C19 gena na pojavu pojačanog odgovora na klopidogrel koje vodi povišenom riziku od krvarenja. Istraživanje je sprovedeno u grupi pacijenata koji su pretrpeli infarkt miokarda i bili podvrgnuti perkutanoj koronarnoj intervenciji (PCI), kao i grupi pacijenata sa stenozom karotida koji su podvrgnuti karotidnoj endarterektomiji (CEA). U studiji su analizirane promotorske varijante rs12248560 (c.-806C>T, CYP2C19*17) i rs11568732 (c.-889T>G, CYP2C19*20) za koje su literaturni podaci i naši preliminarni rezultati pokazali da mogu biti povezane sa pojačanim odgovorom na klopidogrel. Dodatno su analizirane egzonske varijante rs, Wide inter-individual variability in clopidogrel response has been reported. Significant number of patients with inadequate response to clopidogrel experience different adverse effects. Bleeding as an adverse event occurs in about 9% of patients on clopidogrel therapy. It can be life threatening and secondarily, related to higher risk of ischemic events. Variability in clopidogrel response may be explained by different non-genetic and genetic factors. Among genetic factors, the most important role has CYP2C19 gene encoding enzyme responsible for conversion of clopidogrel to its active form. Hence, CYP2C19 gene variants are the most commonly investigated genetic variants related to clopidogrel pharmacogenetics. Clinically, the most relevant variants are rs4244285 (c.681G>A; CYP2C19*2) and rs4986893 (c.636G>A; CYP2C19*3) which lead to clopidogrel poor response. Additionally, promoter variant rs12248560 (c.-806C>T, CYP2C19*17) is associated with elevated platelet inhibition and increased risk of bleeding in patients on clopidogrel. This study was focused on investigating role of CYP2C19 gene in clopidogrel hyper-responsiveness which increases the risk of bleeding. This study was conducted in a group of patients with acute myocardial infarction who underwent percutaneous coronary intervention (PCI) as well as in patients with carotid stenosis who underwent carotid endarterectomy (CEA). In this study we examined two promoter rs12248560 (CYP2C19*17) and rs11568732 (CYP2C19*20) variants, for which literature and our preliminary results showed to be associated with elevated clopidogrel response. Additionally, we analyzed exonic variants rs4244285 (c.681G>A; CYP2C19*2) and rs4986893 (c.636G>A, CYP2C19*3) considering their potential influence on the promoter variants’ effects. Since literature data on rs11568732 (c.-889T>G, CYP2C19*20) variant is scarce, we aimed to investigate its functional significance. Further, one of our aims was the anlysis of the relevant CYP2C19 varia

The correct Author names are shown in this paper.

Bleeding is one of the possible adverse events during clopidogrel therapy. The CYP2C19 gene is the most significant genetic factor which influences response to clopidogrel treatment. We aimed to examine the contribution of the CYP2C19 gene to bleeding occurrence during clopidogrel therapy in Serbian patients with ST segment elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PCI). This case-control study included 53 patients who experienced bleeding and 55 patients without bleeding. Bleeding events were defined and classified using the Bleeding Academic Research Consortium (BARC) criteria. All patients were prescribed daily doses of clopidogrel during the 1-year follow-up after PCI. The CYP2C19*17 (c.-806C gt T, rs12248560), rs11568732 (c.-889T gt G, CYP2C19*20), CYP2C19*2 (c.681G gt A; rs4244285) and CYP2C19*3 (c.636G gt A; rs4986893) variants were analysed in all 108 patients. Additionally, sequencing of all nine exons, 5'UTR and 3'UTR in the rs11568732 carriers was performed. Association between bleeding (BARC type ae lt yen gt 2) and the CYP2C19*17 variant was not observed [odds ratio (OR), 0.53; 95% confidence interval (CI), 0.2-1.1; p = 0.107). The rs11568732 variant showed significant association with bleeding (OR, 3.7; 95% CI, 1.12-12.44; p = 0.025). Also, we found that the rs11568732 variant appears independently of haplotype CYP2C19*3B, which is contrary to the previous findings. Our results indicate the absence of CYP2C19*17 influence and turn the attention to the potential significance of the rs11568732 variant in terms of adverse effects of clopidogrel. However, it is necessary to conduct an independent conformation study in order to verify this finding. Also, an analysis of the functional implication of the rs11568732 variant is necessary in order to confirm the significance of this variant, both in relation to its influence on gene expression and in relation to its medical significance.

Introduction: Clopidogrel, which is activated by the CYP2C19 enzyme, is among the drugs for which all major regulatory agencies recommend genetic testing to be performed to identify a patient's CYP2C19 genotype in order to determine the optimal antiplatelet therapeutic scheme. The CYP2C19*2 and CYP2C19*3 variants are loss-of-function alleles, leading to abolished CYP2C19 function and thus have the risk of thrombotic events for carriers of these alleles on standard dosages, while the CYP2C19*17 allele results in CYP2C19 hyperactivity. Aims: Here, we report our findings from a retrospective study to assess whether genotyping for the CYP2C19*2 allele was cost effective for myocardial infarction patients receiving clopidogrel treatment in the Serbian population compared with the nongenotype-guided treatment. Results: We found that 59.3% of the CYP2C19*1/*1 patients had a minor or major bleeding event versus 42.85% of the CYP2C19*1/*2 and *2/*2, while a reinfarction event occurred only in 2.3% of the CYP21C9*1/*1 patients, compared with 11.2% of the CYP2C19*1/*2 and CYP2C19*2/*2 patients. There were subtle differences between the two patient groups, as far as the duration of hospitalization and rehabilitation is concerned, in favor of the CYP2C19*1/*1 group. The mean cost for the CYP2C19*1/*1 patients was estimated at (sic)2547 versus (sic)2799 in the CYP2C19*1/*2 and CYP2C19*2/*2 patients. Furthermore, based on the overall CYP2C19*1/*2 genotype frequencies in the Serbian population, a break-even point analysis indicated that performing the genetic test prior to drug prescription represents a cost-saving option, saving (sic)13 per person on average. Conclusion: Overall, our data demonstrate that pharmacogenomics-guided clopidogrel treatment may represent a cost-saving approach for the management of myocardial infarction patients undergoing primary percutaneous coronary intervention in Serbia.

Venous thromboembolism is a multifactorial disorder with two manifestations: deep-vein thrombosis and pulmonary embolism. Pulmonary embolism is usually considered as the complication of deep-vein thrombosis, but there are reported cases of isolated pulmonary embolism. FV Leiden and FII G20210A mutations are most common genetic risk factors for the venous thromboembolism. Several studies reported "FV Leiden paradox": lower prevalence of FV Leiden mutation among patients with isolated pulmonary embolism than among those with deep-vein thrombosis. The aim of this study was to determine FV Leiden and FII G20210A mutations frequency in thrombophilic patients in Serbian population. We tested prevalence of these mutations carriers in 1427 individuals divided in three groups of patients (with deep-vein thrombosis, deep-vein thrombosis/pulmonary embolism and isolated pulmonary embolism) and control group. All subjects were tested for these mutations using PCR-RFLP analysis. Detected frequency of FV Leiden heterozygous carriers in patients with isolated pulmonary embolism was 6.9% (for FII G20210A 11.6%), while in other two groups of patients with deep-vein thrombosis and deep vein thrombosis/pulmonary embolism, frequency was 18.6% (for FII G20210A mutation were 11.6% and 8.3%, respectively). Our results showed that FV Leiden mutation is less frequent in patients with isolated pulmonary embolism than in patients with deep-vein thrombosis or deep-vein thrombosis accompanied with pulmonary embolism, confirming "FV Leiden paradox". On the other hand, detected frequency of FII G20210A mutation carriers was similar in all three groups of patients.

Objective Pulmonary embolism is usually considered as a complication of deep vein thrombosis, but there are still a number of cases of isolated pulmonary embolism. We aimed to investigate whether prothrombin 3’ end gene variants might play a signifi cant role in the pathogenesis of isolated pulmonary embolism. Methods and results In this study 100 patients with isolated pulmonary embolism and 100 controls were screened by DNA sequencing. Screening included last intron, last exon, 3’UTR and part of the 3’FR region of the prothrombin gene. Our results have shown that heterozygous carriers of the FII G20210A variant have a signifi cantly higher risk of isolated pulmonary embolism (OR 4.83; 95%CI 1.33-17.52; P = 0.02). Carriers of the FII 19911GG genotype (OR 1.41; 95%CI 0.72-2.73; P = 0.31) and FII 20068CT genotype (OR 3.06; 95%CI 0.31-29.95; P = 0.34) were more frequent in patients with isolated pulmonary embolism compared to controls. We also detected the novel gene variants, FIIc.*64_*66del and FII c.*303T gt C, in two patients. Conclusions Our results suggest that FII G20210A represents a signifi cant risk factor for isolated pulmonary embolism. The FII G19911A and FII C20068T are potentially associated with an increased risk for the occurrence of isolated pulmonary embolism, but the results did not reach statistical signifi cance. This is the fi rst study in which the two novel 3’ end prothrombin gene variants, FIIc.*64_*66del and FII c.*303T gt C, were reported.

Odgovarajuća tromboprofilaksa podrazumeva pravovremeno identifikovanje reverzibilnih i ireverzibilnih faktora rizika za venski tromboembolizam (VTE), kao i njihovu kategorizaciju. Podaci da najveći procenat plućnih embolija nastaje kod bolesnika sa nehirurškim oboljenjima i da se kod hirurški lečenih bolesnika VTE uglavnom javlja posle otpusta iz bolnice nameću potrebu za odgovarajućom zaštitom od VTE osoba obolelih od inflamatornih oboljenja, akutnih bolesti i drugih nehirurških oboljenja, kao i produženjem i optimalizacijom antikoagulantnog režima posle hirurških intervencija u primarnoj profilaksi VTE. Kao gotovo potpuno neprepoznate i u praksi zanemarene značajne faktore rizika za VTE posebno ističemo hroničnu opstruktivnu bolest pluća (HOBP) i insuficijenciju srca, naročito kod bolesnika koji pripadaju trećoj i četvrtoj funkcionalnoj klasi prema klasifikaciji Njujorškog udruženja za srce (NYHA III i IV) sa značajno smanjenom funkcijom leve komore. Postoji opasnost da se kod bolesnika sa HOBP znaci dispneje i kašalj jednostrano pogrešno protumače kao tipični simptomi uzrokovani isključivo osnovnom respiratornom bolešću, a da se znaci pogoršanja oboljenja kod osoba s insuficijencijom srca pripišu samo pogoršanju kardijalnog statusa, zanemarujući mogućnost da je u osnovi reč o plućnom tromboembolizmu koji nije na odgovarajući način prepoznat i lečen. Savremeni način života pogoduje nastanku novih faktora rizika za VTE, kao što je 'putnička' tromboza, naročito kod osoba koje lete na dugačkim avionskim linijama, kao i ljudi koji veći deo dana sede ispred kompjutera (engl. e-thrombosis). Utvrđivanje i prepoznavanje faktora rizika za VTE, naročito zanemarenih nehirurških, i istovremenog postojanja višestrukih faktora rizika u određenom vremenskom intervalu neophodno je radi određivanja odgovarajućeg antikoagulantnog terapijskog režima kod bolesnika s nehirurškim oboljenjima i onih koji su hirurški lečeni u primarnoj prevenciji VTE., Adequate thromboprophylaxis primarily requires timely detection of reversible and irreversible risk factors of venous thromboembolism (VTE) and their categorization. It is important to note that the highest percentage of VTE episodes occur in non-surgical (medical) patients and that VTE develops in a large number of surgical patients upon hospital discharge; this emphasizes the need for adequate VTE prevention in inflammatory diseases, acute medical illness and other medical diseases as well as for prolonging and optimizing the anticoagulant regimen after surgical intervention in the primary VTE prophylaxis. As almost completely unrecognized and neglected major risk factors of VTE in clinical practice, we particularly point out the chronic obstructive pulmonary disease (COPD) and heart failure, especially in NYHA functional class III and IV patients with significantly reduced left heart ventricle. It is necessary to raise clinicians' awareness of a potential danger from wrongly and one-sidedly interpreted dyspnea and coughing signs in patients with COPD as typical symptoms of basic respiratory disease as well as from ascribing the signs of disease aggravation in heart failure patients exclusively to cardial status worsening, neglecting the possibility of having unrecognized and untreated pulmonary embolism at issue. Contemporary way of life enhances the development of new VTE risk factors such as traveler's thrombosis, in particular during long-haul flights as well as in individuals sitting at a computer for prolonged periods (e-thrombosis). Determining and recognizing VTE risk factors, especially those formerly neglected nonsurgical ones and simultaneous presence of multiple risk factors within a given period is required for defining an adequate anticoagulant regimen in primary VTE prophylaxis for surgical and non-surgical (medical) patients.

Uvod: Inhibitor aktivatora plazminogena 1 (PAI-1) ima značajnu ulogu u procesu inhibicije fibrinolize i normalne hemostaze. Prisustvo PAI-1 4G/4G genotipa uzrokuje povećanje ekspresije PAI-1. Povišen nivo PAI-1 u krvi povezan je sa brojnim bolestima kao što su tromboza, moždani udar, infarkt miokarda, spontani pobačaji, preeklampsija, insulinska rezistencija, dijabetes tipa 2, rak dojke i astma. U okviru ove studije određivana je učestalost PAI-1 4G/5G genske varijante kod zdravih ispitanika u srpskoj populaciji. Metode: Studija je obuhvatala grupu od 210 zdravih ispitanika (105 žena i 105 muškaraca). Prisustvo PAI-1 4G/5G genske varijante detektovano je PCR-RFLP metodom. Rezultati: Učestalost PAI-1 4G/4G genotipa iznosila je 34,76% i bila je povećana u odnosu na PAI-1 5G/5G genotip (19,05%), dok je najzastupljeniji genotip bio PAI-1 4G/5G (46,19%). Učestalost 4G alela bila je viša (0,58) u odnosu na 5G alel (0,42). Zaključci: Učestalost PAI-1 4G/5G genske varijante u srpskoj populaciji slična je sa okolnim populacijama. Rezultati ove studije su značajni, jer predstavljaju prve podatke za srpsku populaciju što će omogućiti dalja istraživanja o ulozi PAI-1 4G/5G genske varijante u patogenezi brojnih bolesti., Introduction: Plasminogen activator inhibitor 1 (PAI-1) has a major role in inhibition of firinolysis and normal haemostasis. The presence of the PAI-1 4G/4G genotype leads to increased expression of PAI-1. High blood level of PAI-1 is associated with many diseases such as thrombosis, cerebral insult, myocardial infarction, pregnancy loss, preeclampsia, insulin resistance, type 2 diabetes, breast cancer and asthma. In this study, the prevalence of PAI-1 4G/5G gene variant was determined in healthy subjects from Serbian population. Methods: The study was carried out in a group of 210 healthy subjects (105 women and 105 men). The presence of PAI-1 4G/5G gene variant was detected by PCR-RFLP analysis. Results: The prevalence of PAI-1 4G/4G genotype was 34.76% and it was increased compared to PAI-1 5G/5G genotype (19.05%). The most frequent was PAI-1 4G/5G genotype (46.19%). Allelic frequency for 4G allele was higher (0.58) compared to 5G allele (0.42). Conclusions: The prevalence of PAI-1 4G/5G gene variant in Serbian population is similar to the neighboring populations. Results of this study represent the first data for Serbian population. This study could be useful for further research where the role of PAI-1 4G/5G gene variant will be assessed in the pathogenesis of many diseases.

The role of thrombophilia in the pathogenesis of stroke is still controversial, especially in the pediatric stroke. In order to examine the role of common thrombophilic mutations in children and adults with stroke, a case-control study was carried out in a group of 80 children and 73 younger adult patients. The control groups encompassed 100 healthy children and 120 healthy blood donors. Our results showed no significant differences in the frequency of factor V (FV) Leiden, FII G20210A, and methylenetetrahydrofolate reductase (MTHFR) C677T variants between patient groups and corresponding controls. According to our results, carriers of 677CT genotype have 3.62 higher risks to develop stroke in children than in adults (P lt .001). The obtained data indicate that heterozygosity for MTHFR C677T variant represents a possible important risk factor for pediatric stroke and suggest a different role of this gene variant in etiology of stroke in pediatric and adult patients.

Tromboze dubokih vena (TDV) su multifaktorijalno oboljenje koje se javlja sa učestalošću 1/1000 stanovnika godišnje. Mutacije FV Leiden, FII G20210A i MTHFR C677T predstavljaju genetske faktore za nastanak venskih tromboza. Cilj ove studije je da se utvrdi učestalost FV Leiden, FII G20210A i MTHFR C677T mutacija kod bolesnika sa TDV gornjih ili donjih ekstremiteta. Studija je obuhvatila 119 bolesnika podeljenih u dve grupe. Grupa bolesnika sa TDV donjih ekstremiteta brojila je 77, a grupa sa TDV gornjih ekstremiteta 42 bolesnika. Prisustvo FV Leiden, FII G20210A i MTHFR C677T mutacija dokazivano je umnožavanjem odgovarajućeg fragmenta gena pomoću lančane reakcije umnožavanja polimerazom i digestijom dobijenih fragmenata restrikcionim enzimima (PCR-RFLP).Učestalost FV Leiden mutacije, u grupi bolesnika sa TDV donjih ekstremiteta, iznosila je 26,0% u heterozigotnom obliku i 1,3% u homozigotnom obliku. U grupi bolesnika sa TDV gornjih ekstremiteta, učestalost heterozigotnih nosilaca iznosila je 7,2%. Mutacija FII G20210A bila je prisutna kod 15,6% ispitanika u grupi bolesnika sa TDV donjih ekstremiteta u heterozigotnom obliku, dok je u grupi sa TDV gornjih ekstremiteta ova mutacija bila zastupljena sa 7,2% u heterozigotnom i 2,3% u homozigotnom obliku. Učestalost MTHFR C677T mutacije kod bolesnika sa TDV donjih ekstremiteta iznosila je 42,8% u heterozigotnom obliku i 13% u homozigotnom obliku, a kod TDV gornjih ekstremiteta 52,4% u heterozigotnom obliku i 9,5% u homozigotnom obliku.Mutacije FV Leiden i FII G20210A predstavljaju značajne faktore rizika za nastanak TDV donjih ekstremiteta. Kod TDV gornjih ekstremiteta ove mutacije su manje zastupljene i potrebno je sprovesti dalja istraživanja koja obuhvataju veći broj bolesnika. MTHFR C677T mutacija je manje značajan faktor rizika i treba ga razmatrati samo u slučajevima kada se pojavljuje u kombinaciji sa drugim faktorima rizika., Deep vein thrombosis (DVT) is a multifactorial disease that occurs with frequency of 1/1000 per year. The FV Leiden, FII G20210A and MTHFR C677T mutations represent genetic factors for the occurrence of vein thrombosis. The goal of this study was to determine the frequency of these mutations in patients with DVT of upper and lower limbs. The study encompassed 119 patients divided in two groups. The group of patients with the lower limbs thrombosis included 77 patients, while the upper limbs thrombosis group included 42 patients. The presence of FV Leiden, FII G20210A and MTHFR C677T mutations was detected by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis. In patients with DVT of lower limbs, the frequency of FV Leiden mutation was 26,0% in heterozygous form and 1,3% in homozygous form. In the group of patients with DVT of upper limbs, the frequency of heterozygous carriers was 7.2%. In patients with DVT of lower limbs, FII G20210A mutation occurred in heterozygous form in 15.6% subjects, and in the group with DVT of upper limbs the frequency was 7.2% in heterozygous and 2.3% in homozygous form. The frequency of MTHFR C677T mutation in patients with lower limbs DVT was 42.8% in heterozygous form and 13% in homozygous form, while in the group of patients with upper limbs DVT, the frequency was 52.4% in heterozygous form and 9.5% in homozygous form. The FV Leiden and FII G20210A mutations represent significant risk factors for the occurrence of DVT of lower limbs. These mutations are less frequent in DVT of upper limbs and more extensive further studies are needed to determine their potential role. The MTHFR C677T mutation represents less significant risk factor for lower limb DVT and should be taken into account only in cases when it occurs in combination with other risk factors.

Recurrent fetal loss (RFL) is common health problem affecting up to 5% of women of reproductive age. It has been shown that plasma thrombin-activatable fibrinolysis inhibitor (TAFI) concentrations increase during pregnancy and return to baseline levels soon after delivery. The +1040C/T single nucleotide polymorphism in coding region of TAFI gene is associated with TAFI blood levels. The aim of our study was to investigate the relationship between +1040C/T polymorphism in TAFI gene and idiopathic RFL. Study was carried out in a group of 120 women (61 controls and 59 women with idiopathic RFL). The R1040C/T polymorphism was detected by restriction fragment length polymorphism PCR. Increased frequency of +1040T/T genotype was observed in a study group, but without statistically significant difference. Carriers of T/T genotype have increased risk of fetal loss by 1.23-fold, compared with carriers of C/C (95% CI 0.462-3.277; P=0.7) and 1.34-fold compared with carriers of C/T genotype (95% CI 0.501-3.601; P=0.6). C allele is associated with reduced risk of recurrent fetal loss compared with T allele (OR 0.91; 95% CI 0.545-1.533; P=0.7). In conclusion, we observed increased frequency of +1040T/T genotype in a patient group, suggesting that this genotype could be potential risk factor for idiopathic RFL. Further investigation should be carried out in order to establish the role of this polymorphism in the etiology of idiopathic recurrent miscarriages. Blood Coagul Fibrinolysis 21: 679-682

Backgound/Aims: Existing data regarding the prevalence of thrombophilia in women with pregnancy complications are conflicting. Methods: To investigate the relationship between pregnancy-associated complications and the presence of thrombophilia, we studied the records of 453 women with pregnancy-associated complications. In 55 women, intrauterine fetal death ( fetus mortus in utero, FMU) after 20 weeks of gestation was recorded, in 231 two or more consecutive recurrent fetal losses (RFL) were recorded, while 167 had a venous thromboembolism (VTE) during one of their pregnancies. The control group consisted of 128 healthy women, with no previous history of thrombotic events or miscarriages. Results: In the FMU group we found 54.5% of women had thrombophilia, in the RFL group 38%, and in the VTE group 52.7%. The most frequent thrombophilia in the VTE group was the FV Leiden ( OR 17.9, 95% CI 4.2-75.9). The most frequent thrombophilia in the FMU group was the FII G20210A ( OR 7.09, 95% CI 1.8-27.9). Statistical difference between RFL and the control group was observed only for FV Leiden ( OR 6.8, 95% CI 1.6-29.7). Conclusion: Thrombophilia was found to be considerably more common in women with pregnancy-associated complications in comparison with the women with normal pregnancies, most frequently in patients with VTE or FMU.

Factor V Leiden (FVLeiden) and prothrombin G20210A are the most common genetic causes of thrombophilia and established risk factors for different clinical manifestations of venous thromboembolism (VTE). This study investigated whether the clinical manifestation of VTE, the extension of deep vein thrombosis (DVT) and the presence of transient risk factors at the time of the first VTE, differed among patients with mutations (97 with FVLeiden; 33 with prothrombin G20210A) and in 109 patients without thrombophilia. Isolated pulmonary embolism (PE) was less prevalent in patients with FVLeiden (6%) and no thrombophilia (6%) than in those with prothrombin G20210A (15%). No difference was found in the incidence of distal DVT. Regarding the extension of proximal DVT, the lowest incidence for isolated popliteal vein and the highest for iliofemoral vein were observed in patients with prothrombin G20210A. No difference was observed between groups of patients with or without thrombophilia by unprovoked VTE. The pregnancy/puerperium was the most prevalent risk factor in carriers of prothrombin G20210A. Among FVLeiden carriers, the most prevalent risk factor was surgery, and in patients without thrombophilia, it was trauma (P lt .05). Thrombosis of the upper limb was more frequent in a group without thrombophilia than in patients with mutations (P lt .01). Transverse sinus venous thrombosis was present only in patients with prothrombin G20210A. Carriers of prothrombin G20210A have an increased risk of developing isolated PE and more severe clinical manifestations than those with FVLeiden or without thrombophilia.

An immune-mediated, severe, acquired prothrombotic disorder, heparin-induced thrombocytopenia type II (HIT II) occurs in 0.5-5% of patients exposed to unfractionated heparin longer than 5-7 days. Arterial and venous thromboses are induced by HIT II in about 35-50% of patients. Typical death rate for HIT is about 29%, while 21% of HIT patients result in amputation of a limb. The trend towards the occurrence of HIT due to the administration of low molecular weight heparins (LMWH) taking ever conspicuous place in the standard venous thromboembolism (VTE) prophylaxis has been more frequently observed recently. It is considered that LMWH may cause HIT II in about 0.25-1%. The need for further modification of HIPA assays with LMWH has been imposed in the HIT laboratory diagnostics, heretofore overburdened with complexity. There are several constantly opposing problems arising in HIT laboratory diagnostics, one of which is that in a certain number of patients immunologic assays detect nonpathogenic antibodies (mainly IgM or IgA heparin-PF4 antibodies) while, on the other hand, the occurrence of HIT pathogenetically mediated by minor antigens (neutrophil-activating peptide 2 or interleukin 8) may be neglected in certain cases. The following factors play an important role in the interpretation of each laboratory HIT assays performed: 1. correlation with HIT clinical probability test, the best known of which is 4T'score, 2. the interpretation of the laboratory findings dependent on the time of the thrombocytopenia onset, as well as 3. the sensitivity and specificity of each test respectively. The HIT diagnostics in the presence of other comorbid states which may also induce thrombocytopenia, more precisely known as pseudo HIT (cancer, sepsis, disseminated intravascular coagulation, pulmonary embolism, antiphospholipid syndrome, etc), represents a specific clinical problem.

Introduction The optimal treatment of pregnancy associated VTE (venous thromboembolism) has not been established yet. Objective The assessment of the efficacy and safety of low molecular weight heparin (LMWH) nadroparin and unfractionated heparin (UFH) used for the treatment of pregnancy and puerperium related VTE. Primary study goals were to analyze the incidence of recurrent VTE (proximal extension or pulmonary thromboembolism), thrombocytopenia, major and minor hemorrhages and skin allergic reactions. The study also included the incidence of miscarriages, stillbirth and neonatal abnormalities. We also studied the relationship between the presence of thrombophilia and the occurrence of complications during VIE treatment. Methods Seventy-two women with antepartal VTE treated with s.c. LMWH during entire pregnancy and 88 women with postpartal VIE initially treated with either s.c. LMWH or i.v.UFH were under follow-up during the entire treatment. Thrombophilia testing included antithrombin, protein C and protein S activity levels, Activated protein C (APC) resistance, LA, ACL, FV Leiden, FII G20210A and MTHFR C677T mutations. Results Twice a day weight based therapeutic regimen was applied for LMWH and activated partial thromboplastin time (aPTT) adjusted UFH dosages. After 2-6 weeks of antepartal deep vein thrombosis (DVT) treatment the dose of nadroparin was reduced to intermediate level. The duration of LMWH therapy during pregnancy was 1-35 weeks, on average 16 weeks. One case (0.62%) of DVT propagation into the vena cava occurred in a woman with antithrombin deficiency treated with LMWH. Two women (1.25%) had minor bleeding and 5 (3.125%) had minimal bleeding, while 3 (1.9%) had skin allergic reactions. The rate of successful pregnancy outcome was 97.2%. There were no cases of stillbirth or neonatal congenital abnormalities. Thrombophilia was found in 86 women (53.7%). No statistically significant correlation between the presence of thrombophilia and treatment c

Hyperhomocysteinemia is considered an independent risk factor for premature cardiovascular disease. Mutation MTHFR C677T reduces the activity of methylenetetra-hydrofolatereductase and may cause hyperhomocysteinemia. Incidence of hyperhomocysteinemia (homocysteine above 12 mu mol/L), homocysteine level, and distribution of MTHFR C677T genotypes (C/C, C/T and T/T) are T/T) are compared between young patients with acute myocardial infarction and healthy persons, matched by age. Study involved 86 patients younger than 45 years (77 men and 9 women) and 35 controls. Homocysteine was measured by an HPLC method and the MTHFR C677T genotype determined using PCR amplification and digestion with Hinf I. Statistical analyses included chisquare and Mann-Whitney U tests. Hyperhomocysteinemia was present in 32.6% patients and 14.3% controls, revealing a significant difference (P = 0.038). Median homocysteine levels in patients (10.4 mu mol/L) and controls (9.6 mu mol/L) were significantly different (P=0.035). Among patients, 50.0% had C/C, 41.9% C/T and 8.1% T/T genotype, and the genotype had no influence on hyperhomocysteinemia incidence and homocysteine level. Genotype distribution in patients was not significantly different from the observed in controls. The conclusion is that young patients with acute myocardial infarction have higher incidence of hyperhomocysteinemia and higher homocysteine levels than healthy young adults, while there is no significant difference in the distribution of MTHFR C677T genotypes.

The absolute rate of recurrence of venous thromboembolism (VTE) is approximately 5% per year. There is a lower rate of recurrence in provoked VTE, and higher in idiopathic one. So far, there is no consensus whether hereditary thrombophilia should be considered as a persistent risk factor, and whether it requires long-term anticoagulant therapy. The aim of our study was to estimate the risk of recurrent VTE in patients carrying FV Leiden mutation in Serbian population. In retrospective study (1994-2006), we have evaluated the risk of recurrent VTE in 56 patients who are carriers of FV Leiden mutation, in comparison to group consisting of 56 patients non-carriers of FV Leiden mutation. Patients with FII G20210A and MTHFR C677T mutations, antiphospholipid antibodies, antithrombin III, protein C or protein S deficiency, malignancies and diabetes were excluded from the study. Recurrent VTE occurred in 44.6% of the patients, carriers of the FV Leiden mutations, vs. 26.7% in non-carriers group (P lt 0.05). The incidence rate was 3.7 and 2.2% per year, respectively. The estimated relative risk of recurrence for FV Leiden carriers was 1.67 (95% CI 0.99-2.81, P = 0.049). The 60% of patients with mutation and only 13% without mutation develop rethrombosis during first year after discontinuance of therapy (P lt 0.01). In our study patients with symptomatic VTE who are carriers of the FV Leiden gene mutations have a higher risk of recurrent VTE than non-carriers. Our data suggest the importance of the FV Leiden mutation detection and the estimation of the clinical condition for successful secondary prophylaxis of VTE.

Treatment of patients with heparin-induced thrombocytopenia type II (HIT II) and thrombosis in some cases that represents a clinical challenge, which, if unrecognized, may lead to treatment delay or disease progression with potentially lethal outcome. We present a case of a 19-year-old patient with antiphospholipid syndrome, factor V (FV) Leiden mutation in heterozygous state, and venous thromboembolism. The patient was subjected to intravenous infusions of unfractionated heparin (UFH), and 16 days after the beginning of the treatment, his condition worsened, with thrombocytopenia and extension of thrombosis. Whereas the patient had a high clinical score for HIT II, functional and antigenic assays for the presence of HIT antibodies were negative. After repeated negative functional and antigenic assays, pseudo-HIT was suspected and nadroparin was introduced, which resulted in further worsening of the clinical presentation. Disease remission, along with complete normalization of platelet count, was finally accomplished with the introduction of lepirudin. The presence of multiple comorbid states, such as antiphospholipid syndrome, can potentially make laboratory confirmation of disease more difficult in patients with HIT II. In our opinion, it is of great importance that HIT II diagnosis be primarily clinical and that laboratory test results are carefully interpreted, especially when HIT is indicated by high clinical score values.