Thrombophilia Screening Tests Research Articles

Thrombophilia and Retina

Retinal vascular occlusions are one of the most common retinal diseases that cause vision loss. Thrombophilia is the tendency of the formation of thrombosis secondary to genetic or acquired factors. The most frequent thrombophilic disorders reported in retinal arterial and venous occlusions are Factor V Leiden mutation and Antiphospholipid Syndrome, whereas the least reported thrombophilic conditions are Anti-thrombin III, Protein S, and Protein C deficiencies. In addition, Hyperhomocysteinemia and Methylenetetrahydrofolate Reductase polymorphism are frequently seen. When retinal vascular occlusions are seen in elderly patients without any systemic diseases, in young patients, in patients with previous thromboembolic events or family thrombosis history, thrombophilia screening tests should be performed in detail.

S1277 The Selection of Donors in Living Donors of Liver Transplantation Based on Results of Thrombophilia Screening Tests and Prophylactic Strategy for Venous Thromboembolic Events (VTE)

Introduction: Vascular events after living donor liver transplantation (LDLT) are one of the most feared complications that usually lead to graft and donor loss. The main aim of this study was to determine the frequency of hereditary thrombophilia in the Pakistani population and share our centers’ safety and venous thromboembolic events (VTE) prophylaxis protocols in the borderline and high-risk groups in live liver donors. Methods: This prospective, observational study included thrombophilia testing, which was done on 567 living donor candidates between July 2018 and April 2021. Donors were divided into the normal, border-line, and high-risk groups according to the Caprini scoring system. Usual prophylaxis with enoxaparin along with elastic stockings and intermittent pneumatic compression (IPC) was given postoperatively to donors in the borderline and high-risk groups. The safety endpoints were VTE occurrence, bleeding complications, or mortality. Results: Among 567 donors, 21 (3.7%) donors were deficient in protein C, 14(2.5%) were deficient in anti-thrombin-III and 45(7.9%) were having Leiden factor-V mutation. 31/416 (7.45%) were deficient in factor-II. IgM & IgG Anti-phospholipids antibodies were positive in 2/567(0.4%) and 2/567(0.4%) respectively. Donor operation was performed on 44 candidates in the borderline group and 7 in the high-risk group. Complications after surgery were comparable between the 2 groups (p >0.05). One donor in the normal donor group developed pulmonary embolism, but none of the donors in either borderline or high-risk group developed VTE. (Table) Conclusion: Early hepatic artery thrombosis (eHAT), deep venous thrombosis, and pulmonary embolism are one of the most common vascular events after liver transplantation.The majority of LDLT centers exclude donors from high-risk groups (according to the Caprini scoring system) and are used to give low molecular weight heparin in borderline donor groups. But we are the only LDLT center where not only did we perform right lobe hepatectomy on high-risk donor group on thrombophilia screening tests, but we also gave usual prophylaxis with enoxaparin (rather than low molecular weight heparin) along with elastic stockings, and intermittent pneumatic compression (IPC) postoperatively to donors in the borderline and high-risk groups (Fifty-one donors ) to decrease the risk of VTE. Table 1. - Comparison of demographics, surgical features, and postoperative complications of LLDs in donor groups Variables Normal Group (n=516) Borderline Group (n=44) High-Risk Group (n=7) P-value Mean age (Years) 23.43 ± 5.53 23.91± 5.25 26.86 ± 6.54 0.17 Mean BMI (Kg/m2) 21.40 ± 7.99 20.5 ± 2.71 21.53 ± 3.29 0.69 GenderMaleFemale 290(56.2%)226(43.7%) 24(54.5%)20(45.4%) 4(57.1%)3(42.8%) 0.97 Marital statusUnmarriedMarried 351(68.1%)165 (31.9%) 25(56.9%)19 (43.1%) 5(71.4%)2(28.5%) 0.06 Donor's relation to recipientsSonBrotherNephewDaughterSisterFatherSwapOthersType of Graft Modified right lobe graftModified extended right lobe graftLeft lobe graftLeft lateral segment graftGRWRMean warm ischemia time (minutes)Mean operation time (hours)Mean blood loss (ml)Blood transfusions (no of patients/ %) 63 (12.2%)99 (19.1%)25 (4.8%)35 (6.7%)32 (6.2%)88 (17.1%)10 (1.9%)157(30.4%)437 (84.6%)62 (12.0%)4 (0.7%)11 (2.1%)6(1.1%)1.26 ± 0.6310.99 ± 6.09407.94 ± 64.86516 6 (13.6%)5 (11.3%)5(11.3%)5 (11.3%)5 (11.3%)3 (6.8%)011 (25.0%)36 (81.8%)8 (18.1%)7 (15.9%)001.4 ± 0.6810.68 ± 4.08412.27 ± 89.1144 1(14.2%)2(28.5%)1(14.2%)00003(42.8%)6(85.7%)1(14.2%)001.2 ± 0.6313.86 ± 7.26422.86 ± 62.377 0.008NSNSNS0.76 Personal History of Thrombosis 0 0 0 _ Total number of complications 62 (12.0%) 15 (34.1%) 2(28.5%) 0.43 Grade 1 & 2 Wound infections Wound hematoma UTI Fever Paralytic ileus 20 (3.8%)2 (0.3%)4 (0.7%)3 (0.5%)2 (0.3%) 3 (6.8%)1 (2.2%)2 (4.5%)2 (4.5%)1 (2.2%) 2(28.5%)0000 0.12 Grade 3A Bile leakage Bile duct stricture Post-op bleeding Pleural effusion/Aspiration ERCP & Stenting 6 (1.1%)3(0.5%)3 (0.5%)9 (1.7%)3 (0.5%) 1 (2.2%)01 (2.2%)1 (2.2%)1 (2.2%) 00000 0.15 Grade 3B Re-open 6(1.1%) 1 (2.2%) 0 0.45 Grade 4A Need ICU care/ ventilatorGrade 4B Multi-organ failure 1 (0.1%)0 1 (2.2%)0 00 0.95-- Grade 5 0 0 0 -- Mean ICU stay (Days) 3 ± 1 2.53 ± 1 3 ± 1 0.15 Mean hospital stay (Days) 6 ± 2 5 ± 2 6 ± 2 0.17 Mortality 0 0 0 -- Abbreviations: BMI: body mass index; GRWR= graft to recipient weight ratio; ICU: Intensive care unit; UTI: Urinary tract infection.

A Case of Extensive Splanchnic Vein Thrombosis in a COVID-19 Patient and a Review of the Literature

: Splanchnic vein thrombosis is one of the rare complications of coronavirus disease 2019 (COVID-19). A 43-year-old woman presented with splanchnic vein thrombosis as a rare extrapulmonary complication of COVID-19. She was previously healthy without a medical history of coagulopathy before hospital admission. She complained of epigastric pain, along with nausea and vomiting. Enhanced abdominopelvic computed tomography (CT) scan demonstrated extensive acute thrombosis in the portal, superior mesenteric, and splenic veins with total occlusion. Intestinal ischemia or infarction was not clinically observed. All thrombophilia screening tests yielded negative results. Under anticoagulation therapy, she recovered dramatically and was discharged from the hospital. Imaging findings can be used to confirm splanchnic vein thrombosis when a COVID-19 patient has abdominal symptoms.

Suspecting classical homocystinuria in an adolescent born before the newborn screening program

Introduction: Classical homocystinuria (HCU) is an autosomal recessive disorder caused by a deficiency in the cystathionine beta-synthase enzyme and associated with a high probability of vascular complications. Herein is presented the case of an adolescent diagnosed with HCU during cerebral venous sinus thrombosis (CVST) study. Case Report: A 14-year-old girl presented with thrombophilia screening tests suggestive of HCU during CVST study. After referral to an Inherited Metabolic Diseases Unit, she started supplementation with pyridoxine, folic acid, vitamin B12, betaine anhydrous, and cysteine and was advised to restrict natural proteins and methionine from diet. Genetic analysis revealed a homozygous CBS mutation (c.572C>T (p.T191M) with c.699C>T (p.Y233Y) polymorphism. Discussion: In adolescents born before 2004 (year of implementation of the Portuguese newborn screening program), HCU should be considered when studying hypercoagulability syndromes, as it is a treatable condition and treatment can prevent major morbidity and mortality causes.

Thrombophilia Screening in Adults Is Not Predictive of a Thrombotic Event after Bipulmonary Lung Transplantation

Introduction: The incidence of venous thrombotic event (VTE ) after lung tansplantation was recently evaluated to approximately 44 % in a large series of patients (Neto et al., Transplantation. 2018; 102: 681). Cystic fibrosis (CF) is a devastating chronic inflammatory disease caused by a mutation in the gene encoding cystic fibrosis transmembrane regulator (CFTR), which is a chloride channel in epithelia cell membranes. Coagulation balance in patient with CF is complexed since there is both a decrease in vitamin K-dependent factor but also an excess of physiological inhibitors deficiencies. Lung fibrosis was also sometimes associated to a higher thrombotic risk. Aim: To analyse whether thrombin generation assay (TGA), which takes in account both pro-and anticoagulant factors, or the activity of soluble tissue factor (TFa) are able to discriminate the thrombotic risk of patients after bipulmonary lung transplantation (BLT) and are better discriminant than classical thrombophilia screening test [prothrombin time (PT), activated partial thromboplastin time (APTT), antithrombin (AT), protein C (PC) S (PS), Z (PZ) fibrinogen (FG) and FVIII levels (FVIIIc) measurements]. Methods: Thrombophilia screening (including TGT in the presence or absence of thrombomodulin (TM) and TFa quantification) was performed for 166 consecutive patients before BLT. Patients were divided in 3 categories : 100 with CF, 43 with chronic obstructive pulmonary disease (COPD) and 23 with idiopathic pulmonary fibrosis (IPF). Among them, 91 (51 with CF, 28 with COPD and 12 with IF) were transplanted. Proven VTE (positive duplex ultrasound) during the first trimester was registered. Results: Because of a defect in lipophilic vitamin absorption, prothrombin time below 70 % and a significant higher proportion of PZ deficiency was observed in patients with CF, in comparison to COPD. The frequency of AT, PC and PS were not significantly different between the 3 groups of patients. Because the chronic pulmonary contamination of the lung by bacteria, the frequency of elevated fibrinogen levels were significantly higher in patients with CF as compared to COPD and IPF groups (table 1). Median TFa values were significantly higher (p < 0.05) in patients with CF (median 0.24 pg/mL, range 0.1 - 7.7) than in patients with COPD (median 0.1 pg/ml, range 0.1 - 0.63). FTa was also elevated (median 0.24, range 0.1 - 6.15) in patients with IPF. Time to Peak (tt-Peak) was significantly shorter in patients with CF as compared to COPD or IPF, even in the presence of thrombomodulin (TM). MRI were higher in patients with CF than in patients with COPD or IPF, even in the presence of TM. Peak was higher in patients with CF as compared to patients with COPD (p < 0.05). In the presence of TM, Endogenous prothrombin potential (ETP) was significantly higher in patients with CF as compared to patients with COPD, and the ratio ETP/ETP with TM was higher in patients with CF as compared to patients with COPD or IPF, indicating a defective PC pathway in patients with CF (table 2). Among the 91 patients with BLT, a VTE was evidenced in 25 (27.5%) patients, with a similar frequency between the 3 groups (33.3 % in CF, 14.7 in COPD, 33.3 % in IPF, not significant). We analysed separately patients with CF from patients with COPD or IPF, since there were differences between coagulation parameters tested in patients with CF. Only APTT ratio was significantly lower (p < 0.01) in patients with CF who had a VTE (1.04) than in patients without VTE (1.12). No difference in the different parameters tested was evidenced in patients with COPD and IPF Conclusion: Even if TGA and TFa clearly evidence a more prothrombotic phenotype in patients with CF than in patients with COPD or IPF, thrombophilia screening before BLT fail to identify patients with a high post-operative thrombotic risk. Disclosures No relevant conflicts of interest to declare.

Clinical Impact of Thrombophilia Screening in Young Adults with Ischemic Stroke

Objective: We evaluated the ability of genetic and serological testing to diagnose clinically relevant thrombophilias in young adults with ischemic stroke. Methods: We performed a retrospective cohort study of patients aged 18-65 years diagnosed with acute ischemic stroke at a comprehensive stroke center between 2011 and 2015 with laboratory testing for thrombophilia. The primary outcome was any positive thrombophilia screening test. The secondary outcome was a change in clinical management based on thrombophilia testing results. Logistic regression was used to assess whether the prespecified risk factors of age, sex, prior venous thromboembolism, family history of stroke, stroke subtype, and presence of patent foramen ovale were associated with outcomes. Results: Among 196 young ischemic stroke patients, at least 1 positive thrombophilia test was identified in 85 patients (43%; 95% CI, 36%-51%) and 16 (8%; 95% CI, 5%-13%) had a resultant change in management. Among 111 patients with cryptogenic strokes, 49 (44%) had an abnormal thrombophilia test and 9 (8%) had a change in management. After excluding cases of isolated hyperhomocysteinemia or methylenetetrahydrofolate reductase or Factor V Leiden gene mutation heterozygosity, the proportion of patients with an abnormal thrombophilia screen decreased to 24%. Prespecified risk factors were not significantly associated with positive thrombophilia testing or a change in management. Conclusions: Two-of-five young patients with ischemic stroke who underwent thrombophilia screening at our institution had at least 1 positive test but only one-in-twelve had a resultant change in clinical management. Neither cryptogenic stroke subtype nor other studied clinical factors were associated with a prothrombotic state.

Longer Duration and Proper Titration of Low Molecular Weight Heparin (LMWH), Are Independent Factors for Successful Pregnancy Outcome. Retrospective Analysis from a Single Center

The role of thrombophilia and LMWH use in pregnancy loss (PL) and pregnancy complications (PC) is debated. In this retrospective study from a single center we analyzed the clinical outcome of pregnancies in relation to thrombophilic factors and the use of LMWH, aspirin and folic acid in 143 women followed up for a total of 173 pregnancies referred to our center from 2003 to 2016.Methods: Women were referred to our unit for: more than 2 unexplained PL (n=96, 78 experienced only early PL, 11 had only late PL, 7 had both early and late), one pregnancy loss(n=45) or one pregnancy complication (placenta abruption, intrauterine growth restriction, eclampsia, n=2). Mutations in Factor V-Leiden (FVL, G1691A), Prothrombin (PTG, G20210A) and MTHFR (C677T, A 1206C) were checked by DNA hybridization Kit. Plasma levels of antithrombin-III, protein-C, free Protein-S, APCR, FVIII, FXII, PT aPTT, fibrinogen, homocysteine and La-test were measured by photometry (DACO). Anticardiolopin and anti-β2GPI antibodies (IGG and IGM) were measured by ELISA in serum (APLA). End points were live birth and pregnancy complications.The prevalence of thrombophilia in our cohort was similar with previous studies and 34/143 (23,4%) women were negative for all thrombophilic factors. We observed mutations in FVL(11,6%), PTG (9,6%), MTHFR (homozygous or double heterozygous, 33,3%) and deficiencies of AT-III (3,3%), Prot-C (1,6%), Prot-S (8,8%), APS (8,7%). Combined severe trombophilic factors were found in 31 women (21,5%) (FVL+PTG 4/31, Natural Anticoagulants one out 3 Def + MTHFR 3/31, APS + MTHFR 2/31, FVL+MTHFR 16/31, PTG + MTHFR 6/31).We then separated our cohort into women with <2 complications or women with >2 complications. The second group had significantly higher incidence of FVL mutation (12,5 vs 8,3%, p=0.05) and deficiencies of AT-III and Free Prot-S ( 6,5 vs 0 %, p=0.01) compared to the first one. By contrast, women in the first group had higher incidence of La-test (12,5 vs 4,5%, p=0,03), APLA ( 12 vs 6,6%, p=0.03) and Prot.C deficiency (4,5 vs 0%, p=0.01).In univariate analysis both hereditary and acquired thrombophilic factors did not correlated with pregnancy outcome (live birth or pregnancy complications). Only age as a continuous parameter correlated negatively with live birth and positively with pregnancy complications (p=0.01 and p=0.025, respectively), whereas high BMI as a continuous parameter also negatively affected live births (p= 0.049). Logistic regression analysis reveals that the age of 35 is the cut off for unfortunate pregnancy outcome.Pregnancies were proceeded with (n=143, 81,7%) or without (n=32, 18,3%,) LMWH. The decision to use LMWH were based in a positive thrombophilia screening test (n=84) or to prior history >2 pregnancy complications with negative trombophilia testing (n=59). Concomitant use of ASA was prescribed in 78 pregnancies (dose less than 100 mg/day) and concomitant follic acid in 143 pregnancies. The percentage of live births were identical in women treated with LMWH (87,4%) or not (87,5%, p=0.9). In multivariate analysis, the only factor that was strongly correlated to live birth was the duration of LMWH treatment (odds ratio, OR =3,567, 95% CI (1.845, 6,894), p= 0,01) and the titration of the dose with anti-Xa (OR=5,138, 95% CI (1,717, 15,376), p = 0,01, fig.1a). By ROC analysis the duration of LMWH which correlated to live birth was ≥ 5.5 months(fig. 1b). The addition of ASA was insignificant for live birth (p=0.7), while the duration (>6months) of follic acid also appeared to add a benefit in combination with LMWH (p=0.01). Moreover, pregnancies proceeded without LMWH exhibited higher rates of pregnancy complications (18,75 vs 11,2%, p=0.08) and prematurity (14,3 vs 8,8%, p=0.05).In summary, our findings argue against hereditary thrombophilia screening in the cases of previous pregnancy loss or pregnancy complications. On the contrary, testing for APS even after the first event might be of value as this population often has laboratory evidence of APS and may benefit from proper anticoagulation. The use of LMWH and folic acid but not of ASA was related to less pregnancy complications or prematurity, whereas proper titration of LMWH by using anti-Xa and long duration of therapy were the only important factors for successful pregnancy outcome. DisclosuresNo relevant conflicts of interest to declare.

Evaluation of the DOAC-Stop® Procedure to Overcome the Effect of DOACs on Several Thrombophilia Screening Tests.

The impact of direct oral anticoagulants (DOACs) on laboratory assays used for thrombophilia testing (e.g., antithrombin, protein S, protein C, lupus anticoagulant and activated protein-C resistance) is a well-known issue and may cause false-positive and -negative results. Therefore, the correct interpretation of tests that are performed in patients taking DOACs is mandatory to prevent misclassification and the subsequent clinical consequences. We aimed at evaluating the efficiency of a new and simple procedure (DOAC-Stop®; Haematex Research, Hornsby, Australia) to overcome the effect of all DOACs in real-life settings and to assess the percentage of erroneous results due to the presence of DOACs on thrombophilia screening tests. For this purpose, 135 DOAC-treated patients (38 apixaban, 40 dabigatran, 15 edoxaban, and 42 rivaroxaban) and 20 control patients were enrolled. A significant drop in apixaban, dabigatran, edoxaban, and rivaroxaban plasma concentrations following the DOAC-Stop® treatment was observed (74.8–8.2 ng/mL [ p < 0.0001], 95.9–4.7 ng/mL [ p < 0.0001], 102.1–8.8 ng/mL [ p = 0.001], and 111.3–7.0 ng/mL [ p < 0.0001], respectively). The DOAC-Stop® treatment was mostly effective to overcome the effect of DOACs on PTT-LA, dilute Russell's viper venom time (dRVVT) screen, and dRVVT confirm tests. Using our procedures, false-positive results due to DOACs were observed only with lupus anticoagulant tests (up to 75%) and fell to zero after the DOAC-Stop® procedure, regardless of the DOAC considered. In conclusion, the DOAC-Stop® adsorbent procedure appeared to be an effective and simple way to overcome the interference of DOAC on coagulation tests and should facilitate the interpretation of thrombophilia screening tests in patients taking DOACs.

Donor Selection and Prophylactic Strategy for Venous Thromboembolic Events in Living Donors of Liver Transplantation Based on Results of Thrombophilia Screening Tests.

BackgroundWe reported a strategy of thrombophilia testing-guided venous thromboembolic events (VTE) prophylaxis for living donors of liver transplantation in 2011. The aim of the present study was to evaluate the safety and efficacy of this protocol for VTE prophylaxis.Material/MethodsThrombophilia testing, including protein S (PS), protein C (PC), antithrombin (AT) III, and anti-phospholipid antibody (APLA), was performed in 306 living donor candidates between July 2005 and June 2016. Donors who met any of the criteria of PS <60%, PC <64%, AT-III <70%, and positive APLA were classified into the borderline group and received continuous venous infusion of heparin immediately after surgery, in addition to use of elastic stockings and intermittent pneumatic compression (IPC) until patients were ambulatory. Other donors who were classified into the normal group used elastic stockings and IPC with no anticoagulants. The efficacy and safety endpoints were VTE occurrence and bleeding events, respectively.ResultsPS was considerably decreased in 3 candidates and PC was considerably reduced in 1 candidate, and they were excluded for high risk of VTE. Seventeen candidates in the borderline group and 137 in the normal group underwent donor surgery. One donor in the borderline group developed a wound hematoma. Postoperative complications were similar between the 2 groups. None of the donors in either group developed VTE.ConclusionsThrombophilia testing-guided VTE prophylaxis is safe and may contribute to reduced VTE risk in donors, although further investigations are warranted to assess the necessity of thrombophilia testing prior to surgery among living donors.

A Case of Multiple Venous Thromboses Associated with Acute Cytomegalovirus Infection

A previously healthy 44-year-old male presented with fever, abdominal pain, liver dysfunction and lymphadenopathy. He was diagnosed as having acute cytomegalovirus (CMV) infection with elevated CMV-IgG and IgM, and observed with supportive therapy. He was admitted to our hospital with prolonged fever lasting for a month. Enhanced CT revealed multiple thromboses in the right pulmonary artery and superior mesenteric vein. Follow-up CT after one week revealed new-onset thromboses in the left pulmonary artery and common iliac vein. Screening tests for thrombophilia were negative. His symptoms were improved with anticoagulant therapy with intravenous heparin, followed by oral warfarin. He was discharged on admission day 28 with good condition. Follow-up CT after 6 months revealed complete resolution of the thromboses. Anticoagulant therapy was stopped after 9 months, and he has been well without recurrence. Though vascular thrombosis is a rare complication, we must be alert to the signs and symptoms of thrombosis in patients with acute CMV infection.

The preliminary research in paroxysmal nocturnal hemoglobinuria with thrombosis

目的探讨阵发性睡眠性血红蛋白尿症（PNH）患者易发血栓的可能因素。方法回顾性分析142例PNH患者的临床资料，对3个已知血栓相关基因位点[PROC c.574_576del（rs199469469）、PROC c.565C>T（rs146922325）和THBD c.-151G>T（rs1698852）]采用Sanger法进行DNA序列检测，以性别、年龄相匹配的100名健康志愿者为正常对照。结果142例患者中，合并血栓者21例（14.8%），其中2例为动脉血栓，19例为静脉血栓，血栓组患者的中位年龄为35（20~67）岁，与非血栓组[40（7~79）岁]比较差异无统计学意义（P=0.687）；两组患者的男女比例、PNH临床分类、HGB、WBC、PLT、LDH水平差异均无统计学意义（P值均>0.05）。血栓组RBC、粒细胞CD59−、红细胞CD59−及嗜水气单胞菌溶素变异体阴性细胞（Flear−）百分率均高于非血栓组（P值分别为0.015、0.005、0.004和0.026）。PNH患者组与正常对照组、PNH血栓组与非血栓组之间蛋白C、蛋白S、抗凝血酶Ⅲ、活化蛋白C抵抗、血脂、狼疮抗凝物等常见易栓因素差异均无统计学意义（P值均>0.05）。PNH患者中，rs199469469位点突变1例（0.704%）、rs16984852位点突变2例（1.408%）、无一例发生rs146922325位点突变，所有突变者均无血栓形成；正常对照组3个位点突变率分别为2.424%、0.873%和0.974%。PNH患者组与正常对照组、PNH血栓组与非血栓组之间各位点突变率差异均无统计学意义（P值均>0.05）。结论RBC与PNH克隆大小是PNH患者发生血栓的独立危险因素。PNH患者与正常人、PHN合并血栓患者与未合并血栓患者相比，常见遗传性和后天获得性易栓因素、常见的静脉血栓3个易感基因的突变率差异均无统计学意义。

An uncommon clinical condition: chronic thrombosis of the inferior vena cava. A case report and review of literature

The lifetime incidence of deep vein thrombosis (DVT) is approximately 0.1% in general population and even more uncommon in subjects below 40 years of age. Thrombosis of the inferior vena cava (IVC) is an exceptionally rare clinical condition, with etiological factors similar to lower limb DVT. We present a case of post-traumatic chronic obstruction of the IVC in 41 years-old man, caused by a prolonged squatted position, while he was working as a bricklayer. We visited the patient fifteen years after the onset of the first clinical setting showing a severe post thrombotic syndrome, as a consequence of the already diagnosticated thrombosis, involving predominantly the right inferior leg. Thrombophilia screening tests showed patient to be a heterozygous carrier of methylenetetrahydrofolate reductase (MTHFR) gene mutation. Computed tomography (CT) scan confirmed the thrombotic obstruction of the infrahepatic IVC, both common iliac veins, right external and internal iliac veins, with multiple collateral pathways. Because of thrombosis extension, inherited prothrombotic condition and the young age of the patient, we decided to continue life-long oral anticoagulant therapy.

Prevalence of Hereditary Thrombophilia in Patients Older Than 75 Years With Venous Thromboembolism Referred for Thrombophilia Screening.

Few studies focused on genetic risk factors for venous thromboembolism (VTE) in the very elderly people. In patients aged 75 years and older with VTE referred for laboratory screening tests for thrombophilia, we aimed: (i) to estimate the F5G1691A and F2G20210A mutation prevalence; (ii) to compare prevalence rates with those of a control group; and (iii) to compare the prevalence rates between patient subgroups, defined as with one or multiple VTE episodes and with provoked/unprovoked VTE. Data were extracted from two prospective thrombophilia registries according to the following inclusion criteria: Caucasian patients aged 75 years and older presenting with at least one confirmed VTE episode. Associated VTE risk factors had been recorded using a standardized questionnaire. Laboratory tests included plasma antithrombin, protein C, and protein S activity measurements and F5G1691A and F2G20210A genotyping. Of the 312 patients (mean age: 84 ± 6 years; 245 women and 67 men), 47.1% had two or more VTE episodes and 63.5% patients had unprovoked VTE. None had deficiencies in antithrombin, protein C, or protein S. The F5G1691A and F2G20210A mutations were found in 29 (9.3%, 95% confidence interval [CI]: 6.3-13.1) and 18 (5.8%, 95% CI: 3.5-9.0) patients, respectively, versus 3.4% (95% CI: 1.9-4.9) and 3.1% (95% CI: 2.6-3.5) in control subjects (p = .0002 and p = .0082, respectively). Overall, 45 (14.4%) patients carried at least one mutated allele. No associations were found between F5G1691A/F2G20210A, unprovoked VTE or recurrence (p > .05). Our study provides new data on genetic risk factors for VTE in the very elderly people. Whether identification of hereditary thrombophilia in elderly patients may influence patient's management in this age group remains unanswered.

Free protein s reference ranges in gravidas without hereditary and acquired thrombophilia.

We carried out a retrospective cohort study to construct reference ranges for free protein S (FPS) levels during pregnancy and identify any conditions or factors that may affect FPS levels. Patients that were ordered thrombophilia screening tests during gestational period were identified. Patients demonstrated to have hereditary or acquired thrombophilia were excluded. Reference ranges were constructed using regression analysis. Outcome of the index pregnancy and pregnancy complications was used to identify any confounding factors. A total of 455 pregnant women were included. The quadratic equation for FPS according to gestational age (GA) was [75.497+(-1.516*GA)+0.018*GA*GA]. FPS level and GA were negatively correlated (Spearmans rho statistic [rs]=-0.436, p=0.001). FPS level and fetal growth restriction (FGR) were negatively correlated ([rs]=-0.093, p=0.049). FPS level and placental abruption were positively correlated ([rs]=0.098, p=0.039). Stepwise linear regression model constructed to predict FPS level with gestational age, placental abruption and FGR as the predictor variables. Gestational age was the only variable retaining statistically significant relation with FPS level (χ(2)=0.216, df=3, p=0.001). FPS levels decrease significantly throughout gestation in gravidas without hereditary and/or acquired thrombophilias. In patients without thrombophilia FPS levels are not associated with pregnancy complications. The obtained reference intervals may be useful for the clinicians ordering FPS during pregnancy.

Ulcerative Colitis and Limb Loss: A Case Report

Introduction: Protein C is a precursor of a vitamin K-dependent serine protease, which is activated by thrombin in the presence of endothelial cofactor, thrombomodulin and endothelial cell protein C receptor. Case Presentation: A 33-year old woman with acute exacerbation of ulcerative colitis was found to have protein C deficiency (serum protein C activity estimated as 35% of the normal activity). Protein C deficiency was diagnosed after the onset of several arterial thromboemboli complications (brachiocephalic and popliteal artery thrombosis) during her hospital admission for exacerbation of ulcerative colitis (UC). Therefore, upper limb below elbow and lower limb below knee amputation were performed for her. Conclusions: After total proctocolectomy, serum protein C activity remained as 35% of the normal activity, so the patient used warfarin as lifelong anticoagulant. Investigation of other family members revealed normal thrombophilia screening tests.

Evaluating Adherence To Clinical Guidelines For Thrombophilia Screening

Thrombophilia is responsible for a majority of unprovoked vascular thrombotic events, with a positivity rate of approximately 65 percent. Thrombophilia is diagnosed by a combination of genetic, activity-based, antigenic, and serologic tests. These evaluations incur significant costs and frequently require unnecessary consultation with specialists. Many of the tests also require follow-up to exclude transient alterations. In order to improve diagnostic yield, screening guidelines for inherited and acquired thrombophilia have been published by the College of American Pathologists and the International Society of Thrombosis and Haemostasis. This study evaluates diagnostic yield and adherence to clinical guidelines for thrombophilia screening at a major university teaching hospital. MethodsWe performed a retrospective review of laboratory Results for thrombophilia screening tests ordered between August 2010 and June 2013. A thrombophilia workup panel was defined as a group of 2 or more thrombophilia tests, including but not limited to protein C (PC), protein S (PS), and antithrombin (AT) activity. For activity-based and PS free antigen testing, the appropriate confirmatory period was defined as at least 30 days from the initial testing date. For LA and/or serologic evidence of anti-phospholipid antibodies, the appropriate confirmatory period was defined as at least 12 weeks from the initial testing date.Subsequently, approximately 10 percent of the charts were randomly selected for complete chart review. Chart histories were evaluated to assess compliance with the screening guidelines published by the College of American Pathologists and the International Society of Thrombosis and Hemostasis. Patients younger than 18 years of age and charts with inadequate documentation were excluded from full review. ResultsWe identified a total of 2081 patients who had thrombophilia screening, representing 4630 unique thrombophilia panels. First time panel orders had an 18% positivity rate, which was significantly lower than the expected positivity rate if guidelines were followed (p<0.01). Appropriate confirmatory testing of PC, PS, and AT deficiencies was performed in 6.0%, 13%, and 4.6% of cases, respectively. Verification of lupus anticoagulant (LA) and/or serologic anti-phospholipid antibodies (aPLs) was performed in 17% of cases. Overall, only 12% of abnormal Results had appropriate follow-up. When repeated, 40% of AT, 46% of PC, 50% of PS, and 39% of LA remained abnormal.Of the 213 charts reviewed, 113 were excluded due to insufficient documentation. Of the remaining 100 charts, only 27% followed the guidelines for both inherited and acquired thrombophilia screening. Inherited thrombophilia screening was more frequently ordered incorrectly (65%) than acquired thrombophilia screening (44%). Overall, 14% of incorrectly ordered panels were due to medication interactions, 95% due to incorrect indications, and 8% due to both reasons. We further evaluated appropriateness of thrombophilia screening by clinical service. Hematologists and oncologists most frequently followed screening guidelines (61%), followed by internists (40%), transplant surgeons (19%), and obstetrics/gynecologist (15%). Neurologists and nephrologists both had 0% percent adherence to screening guidelines. ConclusionThe majority of thrombophilia screening is ordered in the absence of adequate clinical indications and confirmatory testing is inconsistently performed. This leads to significantly increases in costs associated with improper testing and inadequate diagnosis of thrombophilia due to insufficient follow-up. Our study demonstrates an urgent need for educating health care professionals on the appropriate ordering of thrombophilia screening tests and for implementing laboratory intervention for incorrectly ordered tests. Disclosures:No relevant conflicts of interest to declare.

Inappropriate use of protein C, protein S, and antithrombin testing for hereditary thrombophilia screening: an experience from a large university hospital

Deficiencies of protein C, protein S, and antithrombin are the main inherited risk factors in Thai patients with venous thromboembolism, although the prevalence is not high. To evaluate the appropriate use of the testing for these proteins, the test orders of 503 patients were retrospectively reviewed using the proposed guidelines. Inter-rater reliability between two investigators was also calculated. Of 503, 459 (91%; 95% confidence interval 88-93%) of the test orders were inappropriate. The most common cause of inappropriateness was testing during acute thrombosis (42.5%). Results were inconclusive in 105 (20.9%) patients who had isolated decrease in one of the proteins, mostly owing to lack of confirmation of the abnormal results. Kappa index for the reliability of two investigators was 0.79. To enhance the appropriate use of hereditary thrombophilia screening tests, physician education concerning the patient selection, suitable timing for testing and repetition of the tests with abnormal results should be emphasized.

Nécroses cutanées localisées aux points d’injection d’apomorphine

Apomorphine is a specific dopaminergic agonist used in the treatment of severe fluctuations of Parkinson's disease, particularly in patients on L-dopa. The drug is usually given subcutaneously, either as several daily injections or via a continuous subcutaneous delivery system. We describe two cases of localized cutaneous necrosis at the points of subcutaneous apomorphine injection. Two male patients presenting Parkinson's disease were treated by subcutaneous injection of apomorphine. One month later, asymptomatic necrotic lesions measuring from 2 to 5 mm appeared at the injection sites. Complete blood count, standard and advanced coagulation studies and screening tests were normal. One patient had taken acetylsalicylic acid. A skin biopsy showed normal epidermis, oedema of the papillary dermis with perivascular lymphocytic infiltrates, reticular dermal infiltrate with neutrophils, and necrosis of the reticular dermis and hypodermis in one patient, and in the other, necrosis in the epidermis, dermis, hypodermis and skin appendages, with dermal leucocytoclastic vasculitis and cytosteatonecrosis. Due to the severity of necrosis, apomorphine was stopped, resulting in improvement of skin lesions in one patient. In the second, due to the localized nature of the lesions and the improvement in the patient's quality of life since the introduction of apomorphine, the drug was continued, resulting in the appearance of new lesions, which continued to be limited to the injection sites. To our knowledge, this is the first description of biopsy-proven apomorphine-induced localized skin necrosis. Reported cutaneous side effects of the drug include pruritic subcutaneous nodules corresponding to panniculitis with large numbers of eosinophils, allergic contact dermatitis, pigmented nodules resulting from oxidation of apomorphine, and nonspecific rashes. Cutaneous necrosis at injection sites could arise through various mechanisms: localized vasoconstriction ("dopamine necrosis"), direct toxicity of the injected drug, local manifestations of pre-existent coagulation disorders, immunological mechanisms or poor administration technique involving intravascular injection. The specific pharmacodynamic properties of apomorphine rule out vasomotor phenomena in the aetiology of such necrosis. Screening tests for thrombophilia were negative in the first patient. Although the underlying mechanism of this form of necrosis remains unknown, an immunological mechanism of the immune complex type could be considered aetiologically relevant on histological grounds due to the presence of vasculitis in one of the two patients.

Atherothrombosis in 2 Vascular Territories in a Young Woman: Importance of Thrombophilia Testing

The diagnosis and management of complex and multiple inherited thrombophilias is still a challenge for the clinicians involved in this field, clinical events being the result of the interaction between genes, environmental or other acquired factors, and age. Moreover, various clinical manifestations as regards severity or type of event (venous or arterial thrombotic event, obstetrical complications) are cited in these patients. We present the case of a 20-year-old woman, with a 2-month history of third-generation contraceptive use and with recently diagnosed hypercholesterolemia, who presented ischemic events in 2 arterial territories: acute left lower limb ischemia and silent myocardial infarction. Screening tests for thrombophilia, including genetic testing, showed moderate hyperhomocysteinemia and 2 inherited thrombophilic defects. Invasive investigation of the coronary arteries showed the presence of advanced atherosclerotic disease. Management of this complex thrombophilia includes lifetime oral anticoagulation as well as a homocysteine-lowering strategy comprising lifestyle modification and group B (folic acid, B(6), B(12)) vitamin supplementing.

Screening and treatment for heritable thrombophilia in pregnancy failure: inconsistencies among UK early pregnancy units

The significance of heritable thrombophilia in pregnancy failure is controversial. We surveyed all UK Early Pregnancy Units and 70% responded. The majority test routinely for heritable thrombophilias; 80%, 76% and 88% undertook at least one screening test in late miscarriage, recurrent miscarriage and placental abruption, respectively. The range of thrombophilias sought is inconsistent: testing for proteins C and S deficiency and F5 R506Q (factor V Leiden) is most prevalent. Detection of heritable thrombophilia frequently leads to administration of antithrombotics in subsequent pregnancies. Thus, thrombophilia testing and use of antithrombotics are widespread in the UK despite controversies regarding the role of heritable thrombophilia in the pathogenesis of pregnancy complications, and the lack of robust evidence for the efficacy of antithrombotic therapy.