Primary Thrombophilia in Mexico XIII: Localization of the Thrombotic Events in Mexican Mestizos With the Sticky Platelet Syndrome.

The sticky platelet syndrome (SPS) is a common cause of both arterial and venous thrombosis, being a dominant autosomal disease with qualitative platelet alterations and familial occurrence. It is characterized by platelet hyperreactivity with increased platelet aggregability in response to low concentrations of platelet agonists: epinephrine, adenosine diphosphate, or both. The clinical manifestations involve venous or arterial thrombosis, recurrent pregnancy loss, and fetal growth retardation. To analyze the localization of the thrombotic episodes in a cohort of Mexican mestizo patients with SPS. Between 1992 and 2016, 86 Mexican mestizo patients with SPS as the single thrombophilic condition were prospectively identified; all of them had a history of thrombosis. There were 15 males and 71 females. The thrombotic episodes were arterial in 26 cases and venous in 60 (70%). Arterial thrombosis was mainly pulmonary thromboembolism, whereas venous thromboses were identified most frequently in the lower limbs. Mexican mestizo population with SPS is mainly female; the type I of the condition is the most frequent; both arterial and venous thrombosis can occur, and they are mainly pulmonary embolism and lower limbs venous thrombosis, respectively.

Can thrombophilia worsen maternal and perinatal outcomes in cases of severe preeclampsia?

OBJECTIVE: To evaluate whether thrombophilia worsens maternal and foetal outcomes among patients with severe preeclampsia (PE). METHOD: From October 2009 to October 2014, an observational retrospective cohort study was performed on pregnant women with severe PE diagnosed before 34 weeks of gestation and their newborns hospitalized at the Clinics Hospital, FMUSP. Patients who had no heart disease, nephropathies, pre-gestational diabetes, gestational trophoblastic disease, foetal malformation, or twin pregnancy and who underwent thrombophilia screening during the postnatal period were included. New pregnancies of the same patient; cases of foetal morphological, genetic, or chromosomal abnormalities after birth; and women who used heparin or acetylsalicylic acid during pregnancy were excluded. Factor V Leiden, G20210A prothrombin mutation, antithrombin, protein C, protein S, homocysteine, lupus anticoagulant, and anticardiolipin IgG and IgM antibodies were analysed. The groups with and without thrombophilia were compared regarding their maternal clinical and laboratory parameters and perinatal outcomes. RESULTS: Of the 127 patients selected, 30 (23.6%) had thrombophilia (hereditary or acquired). We found more white patients in thrombophilia group (p = .036). Analysis of maternal parameters showed a tendency of thrombophilic women to have more thrombocytopenia (p = .056) and showed worsening of composite laboratory abnormalities (aspartate aminotransferase ≥ 70 mg/dL, alanine aminotransferase ≥ 70 mg/dL, platelets < 100,000/mm3, serum creatinine ≥ 1.1 mg/dL; p = .017). There were no differences in foetal perinatal outcomes. CONCLUSION: The presence of thrombophilia leads to worsening of maternal laboratory parameters among patients with severe forms of PE but without worsening perinatal outcomes.

Primary thrombophilia in Mexico: a single tertiary referral hospital experience.

Thrombophilia is a complex hypercoagulable state that increases the risk of thrombosis. Most reports in medical literature of the Mexican population with this disease lack statistical validity. Therefore, the aim of this study is to describe the prevalence of primary thrombophilia in a tertiary referral hospital in Mexico. This is a study of patients referred to our hospital because of a hypercoagulable state and who later on were diagnosed with primary thrombophilia. The thrombophilia workup included methylenetetrahydrofolate reductase (MTHFR) C677T, antiphospholipid antibodies, protein C, protein S, antithrombin, factor VIII, factor V Leiden, prothrombin mutation G20210A, activated protein C resistance, JAK2 V617F and homocysteine. Ninety-five individuals were tested. The MTHFR C677T polymorphism was the most frequent anomaly in 84.1% of the tested individuals. There was a relatively low prevalence of factor V Leiden (5.2%) and anticoagulant protein deficiency (8.3%). The MTHFR C677T polymorphism has a very high prevalence compared with the low prevalence of anticoagulant protein deficiency and factor V Leiden mutation in Mexicans.

Blood pressure measurement reliability among different racial-ethnic groups in a stroke prevention study.

OBJECTIVE: High blood pressure (BP) is commonly not diagnosed, and patients do not achieve target values when treated. Among 20,000 patients encompassing most races-ethnicities, we evaluated BP measurements and treatment response in a stroke prevention trial. Our goal was to identify BP measurement differences between clinical trial and patient determinations and among the racial-ethnic groups. MATERIALS AND METHODS: A total of 20,332 patients with ischemic stroke were randomized to receive antiplatelet treatment and 80 mg of telmisartan versus placebo. BP measurements were obtained at the first clinic visit and then 1 and 3 months later and every 6 months thereafter. One week after the first clinic visit, patients were requested to report a BP measurement obtained elsewhere. Measurements at the trial clinics were obtained with the same electronic device. Statistical analysis was used to detect significant differences. RESULTS: The mean patient age was 66 years; 36% were women, and race-ethnicity comprised 58% Whites, 33% Asian, 4.9% Hispanic, and 4% Black. Overall, 74% of patients were hypertensive. BP varied between the race-ethnicity groups, being highest in Hispanics (145/85) and lowest in Blacks (144/82). BP at visits clinic 1, nonclinic 1A, and clinic 2 were, respectively, 144/84, 137/80, and 139/81 mmHg, with the difference between visits 1-2 and visit 1A being significant. BPs were normal in 42% of the cases at visit 1A, and of these, only 44% were normal at visit 1 and 57.6% were normal on visit 2. Similar findings were noted for all race-ethnicity groups. CONCLUSION: BP values varied among race-ethnicities and showed differences between clinic and patient measurements. This finding questions the reliability of self-reported BP and has implications for BP management in daily clinical practice.

Polymorphism analysis of MTHFR, factor II, and factor V genes in the Pomeranian population of Espirito Santo, Brazil.

Pomeranian populations worldwide immigrated originally from the north of Europe, and because of their preferential marriage, religion, and cultural habits, they show little or no reproductive mixing with local populations. Methylenetetrahydrofolate reductase gene (MTHFR) C677T, Factor V Leiden, and Factor II G20210A polymorphisms are linked to augmented clotting and their frequencies may vary according to population ethnicity. We aimed to assess the frequencies of these thrombophilic alleles in the Pomeranian population residing in Espirito Santo and compare with the general population of the Espirito Santo state, Brazil. A total of 200 individuals were analyzed. The intrapopulation fixation index of the MTHFR C677T polymorphism was 0.03736. The observed heterozygosity was 0.44 and 0.4 for the general and Pomeranian populations, respectively. According to the chi-square test, both populations are in Hardy-Weinberg equilibrium. Four polymorphic alleles were detected for Factor II (2.02%) and 8 for Factor V (4.81%). Our results show that there is gene flow between the general and the Pomeranian population of Espirito Santo, which should no longer be considered an isolated population.

Analysis of polymorphisms in genes (AGT, MTHFR, GPIIIa, and GSTP1) associated with hypertension, thrombophilia and oxidative stress in Mestizo and Amerindian populations of México.

Several polymorphisms related to hypertension, thrombophilia, and oxidative stress has been associated with the development of cardiovascular disease. We analyzed the frequency of M235T angiotensinogen (AGT), A222V 5,10 methylenete-trahydrofolate reductase (MTHFR), L33P glycoprotein IIIa (GPIIIa), and I105V glutathione S-transferase P1 (GSTP1)} polymorphisms in 285 individuals belonging to Mexican-Mestizo and five Amerindian population from México, by real time PCR allelic discrimination. Allele and genotype frequencies were compared using chi square tests. All populations followed the Hardy Weinberg equilibrium for assay markers with the exception of the Triki, whose were in Hardy Weinberg dysequilibrium for the glutathione S-transferase P1 polymorphism. Interestingly, according to all the analyzed single nucleotide polymorphisms (SNPs), the Triki population was the most differentiated and homogeneous group of the six populations analyzed. A comparison of our data with those previously published for some Caucasian, Asian and Black populations showed quite significant differences. These differences were remarkable with all the Mexican populations having a lower frequency of the 105V allele of the glutathione S-transferase P1 and reduced occurrence of the 222A allele of the 5,10 methylenetetrahydrofolate reductase. Our results show the genetic diversity among different Mexican populations and with other racial groups.

Primary thrombophilia in Mexico. II. Factor V G1691A (Leiden), prothrombin G20210A, and methylenetetrahydrofolate reductase C677T polymorphism in thrombophilic Mexican mestizos.

We have shown that in Mexican mestizo patients with clinical features of primary thrombophilia, 39% have activated protein C resistance phenotype, 5% protein C deficiency, and 2% protein S deficiency. In the present study, in a group of 37 thrombophilic Mexicans and 50 normal controls, we assessed the factor V G1691A (Leiden), the prothrombin G20210A, and the methylenetetrahydrofolate reductase (MTHFR) C677T gene polymorphisms. Four patients were found to be heterozygous for factor V Leiden, 5 heterozygous for the prothrombin 20210, 16 heterozygous, and 6 homozygous for the MTHFR 677. There were four individuals with co-segregation of alleles: two heterozygotes for the factor V Leiden/prothrombin 20210, one heterozygote for prothrombin 20210/MTHFR 677, and one heterozygote for prothrombin 20210/homozygote for MTHFR 677. For factor V Leiden, prothrombin 20210, and MTHFR 677 mutations, the allele frequencies were respectively 1% (+/-0.2%, alpha = 0.05), <1% and 51% (+/-5%, alpha = 0.05), with calculated relative risks for thrombosis of 5.94 (P = 0.08), >7.66 (P < 0.05), and 0.44 (P NS), respectively. In Mexican mestizo thrombophilic patients, the low prevalence of the factor V Leiden mutation (10.8%) and the high prevalence of the prothrombin 20210 mutation (13.5%) contrast with those identified in Caucasian thrombophilic patients (21% and 6%, respectively; P < 0.01). On the other hand, the high prevalence of the MTHFR 677 mutation gene both in normal controls (78%) and thrombophilic patients (61%) does not support a role of this mutation in the thrombogenesis of Mexican mestizo patients.