aPTT Levels Research Articles

Andexanet Alfa Corrects the Interference of Direct Factor Xa Inhibitors on Lupus Anticoagulant Testing

BackgroundDirect Factor Xa (FXa) inhibitors (e.g. rivaroxaban or apixaban) are widely used oral anticoagulants and are known to interfere with dilute Russell's viper venom time (dRVVT) and aPTT-based lupus anticoagulant (LA) testing, often yielding false-positive LA results. A false positive LA result might incorrectly diagnose a patient with the anti-phospholipid antibody syndrome and lead to a wrong decision for long-term anticoagulation to prevent recurrent thrombosis.Andexanet alfa is a recombinant modified human FXa decoy protein that has been specifically designed as an antidote to neutralise the effect of the direct and indirect FXa inhibitors.AimTo determine whether the addition of andexanet alfa can overcome the interference of rivaroxaban and apixaban on LA testing in plasma samples from both LA positive and LA negative patients.MethodsAfter written informed consent, citrated blood (20mL) was collected from 12 patients on therapeutic doses of rivaroxaban (n=6) or apixaban (n=6) with previously known LA status (3/6 LA positive in each group). Samples were double centrifuged at 3,000 x g for 10 minutes and aliquots were frozen at -40oC until analysed. Normal pooled plasma and rivaroxaban and apixaban calibrated plasma was obtained from a commercial source (Diagnostica Stago) or control plasma from healthy volunteers, prepared as above. IgG was purified by a Protein G column from a known LA positive patient and a control healthy volunteer.Rivaroxaban (Bayer) and apixaban (Bristol-Myers Squibb) tablets were crushed and dissolved in DMSO. Andexanet alfa (Portola Pharmaceuticals, Inc.) was dissolved in distilled water and aliquots were frozen at -40oC until used. Plasma samples were spiked with varying concentrations of FXa inhibitors and andexanet alfa.LA-sensitive aPTT, PT, TCT, dRVVT (Siemens Healthcare Diagnostics) and anti-FXa level (Diagnostica Stago) were performed with and without andexanet alfa on the Sysmex CS5100 analyser.Andexanet alfa (at a final concentration of 250µg/mL) was added to LA positive and LA negative plasma samples to assess the impact on the dRVVT normalised ratio.ResultsAndexanet alfa demonstrated a concentration-dependent increase in LA sensitive aPTT and dRVVT clotting times, with negligible impact on PT or TCT. Andexanet alfa was capable of reversing FXa inhibition in a concentration-dependent manner in plasma samples containing rivaroxaban or apixaban.When rivaroxaban is added to normal plasma it significantly prolongs the dRVVT without phospholipid more than with excess phospholipid leading to a false-positive LA ratio at final concentrations >100ng/mL. This level of rivaroxaban is in the therapeutic range. The addition of andexanet alfa reduced the measurable anti-FXa level and returned the normalised dRVVT ratio to LA negative result (<1.25). In contrast, apixaban and andexanet alfa proportionately prolongs the dRVVT with or without excess phospholipid and even at high concentrations, the normalised LA ratio remains negative (<1.25).Andexanet alfa converted the false positive dRVVT rivaroxaban patient plasmas LA ratio to negative. True LA positive patients remained positive after the addition of andexanet alfa. These results were confirmed by adding LA positive and control purified IgG to known concentrations of rivaroxaban and apixaban (200ng/ml) in normal plasma.ConclusionAndexanet alfa corrects the false positive LA ratio in patients on rivaroxaban without affecting the true diagnosis in LA positive patients. Apixaban and andexanet alfa proportionately prolong the dRVVT with and without phospholipid, so the LA ratio remains negative. For this reason true LA positive patients can be diagnosed whilst on apixaban at therapeutic concentrations without the addition of andexanet alfa. DisclosuresBaker:Biogen Idec: Membership on an entity's Board of Directors or advisory committees, Research Funding; Novo Nordisk: Other: Conference travel support; Astellas and CSL Behring: Research Funding; Bristol-Myers Squibb: Research Funding; Boehringer Ingelheim: Membership on an entity's Board of Directors or advisory committees, Research Funding; Bayer: Membership on an entity's Board of Directors or advisory committees, Research Funding; Shire: Membership on an entity's Board of Directors or advisory committees, Other: Conference travel support, Research Funding; Daiichi Sankyo: Research Funding; Portola Pharmaceuticals: Research Funding; Pfizer: Membership on an entity's Board of Directors or advisory committees, Research Funding; Amgen: Membership on an entity's Board of Directors or advisory committees, Other: Conference travel support; Biogen Idec: Membership on an entity's Board of Directors or advisory committees; Alexion Pharmaceuticals: Membership on an entity's Board of Directors or advisory committees, Other: Conference travel support, Research Funding; Roche: Other: Conference travel support. McGregor:Gilead: Membership on an entity's Board of Directors or advisory committees; Bristol-Myers Squibb: Equity Ownership, Other: Conference travel support; Pfizer: Other: Conference travel support; Roche: Honoraria; Abbvie: Equity Ownership; Portola Pharmaceuticals: Equity Ownership.

Low-Dose Heparin in Critically Ill Patients Undergoing Extracorporeal Membrane Oxygenation - the Help-ECMO Pilot Randomised Controlled Trial

Extra corporeal membrane oxygenation (ECMO) is a rescue therapy for reversible cardiac and/or respiratory failure. Despite improvement in management of patients undergoing ECMO, mortality remains high. Due to thrombosis risk, which includes arterial and venous thrombosis as well as in the extracorporeal circuit and components, variable intensity systemic anticoagulation with unfractionated heparin is routinely used. However, bleeding is one of the most frequent complications, can be severe and is independently associated with worse outcomes. Optimal anticoagulation to prevent thrombosis whilst minimising bleeding in adults on ECMO remains unknown. Before conducting a large randomised controlled trial to determine whether lower anticoagulation intensity is safe and effective compared with therapeutic anticoagulation, we aimed to determine the feasibility of randomising ECMO patients to these anticoagulation protocols.Methods:The HELP-ECMO pilot study (ACTRN12613001324707) is a randomised, controlled, unblinded trial at two Australian intensive care units (ICUs). Inclusion criteria were ICU patients who required ECMO (venous-venous [VV] or venous-arterial [VA]). Patients who did not meet any exclusion criteria were randomised to receive either therapeutic anticoagulation with heparin (target activated partial thromboplastin time [aPTT] between 50 and 70 seconds) or low dose heparin (12000 units/24 hours aiming for aPTT <45 seconds). Paired aPTT and anti-Xa assays were taken according to protocol, and at a minimum once a day. The primary endpoints for feasibility were difference in mean heparin dose, aPTT and anti-Xa levels between both study groups. Secondary endpoints included incidence of thromboembolic events, ECMO circuit thrombosis and bleeding events. All primary outcomes were log-transformed prior to analysis and reported as geometric means (95%CI) with overall differences determined using Repeat measures ANOVA.Results:Between May 2014 and March 2016, 31 patients who underwent ECMO (9 (29%) VA and 22 (71%) VV) were enrolled; 16 were randomised to low dose and 15 to therapeutic dose heparin. The groups were similar in age (mean 41 years [SD 16.8] vs 43 [SD 17.6] p=0.75), gender (68% vs 80% male, p=0.47), type of ECMO (31% vs 27% VA, p=0.78) and Acute Physiology and Chronic Health Evaluation III illness severity score (mean 65.4 [SD 23.5] vs 61.8 [SD 30.1], p=0.72) and sepsis-related organ failure assessment score (mean 10 [SD 3.6] vs 10 [SD 3.3], p=1.0). The mean duration of ECMO support was 9.33 days (SD 5.97) in the low dose and 9.79 days (SD 4.77) in the therapeutic dose group (p=0.82).For the primary outcomes, there was a significant difference in the daily mean aPTT (48.1 [95% CI 43.5-53.3] vs 56.2 [95% CI 50.7-62.3], p=0.03), daily mean anti-Xa (0.11 [95% CI 0.07-0.18] vs 0.30 [IQR 0.19-0.46], p=0.003) and daily mean heparin dose (11784 units [95% CI 8693-15972] vs 22050 [IQR 16262-29899], p=0.004) in the low dose compared to therapeutic group.There was no difference in thrombotic complications with regard to DVT (2 [12.5%] vs 3 [20%], p=0.57), PE (1 [6.3%] vs 0 [0%], p=0.33), stroke (no events), intracardiac thrombus (1 [6.3%] vs 2 [13.3%], p=0.51), acute pump (1 [6.3%] vs 1[6.7%], p=0.96) and distal perfusion cannula thrombosis (2 [12.5%] vs 0 [0%], p=0.16) in low dose compared with therapeutic group, respectively.With regard to bleeding, there was no difference in intracranial haemorrhage (ICH) (0 [0%] vs 1 [6.7%], p=0.29), retroperitoneal bleeding (1 [6.3%] vs 1 [6.7%], p=0.96), gastrointestinal bleeding (0 [0%] vs 2 [13.3%] , p=0.13), or haemoptysis (1 [6.5%] vs 1 [6.7%], p=0.96) in low dose compared with therapeutic group, respectively.Conclusion: In this pilot trial, administration of a low dose heparin protocol was feasible, and resulted in a significant difference in mean heparin dose administered and daily aPTT and anti-Xa levels between groups. Low dose heparin was not associated with an increase in thrombotic events nor a decrease in bleeding events; however the study was not powered for these outcomes. Our findings support the feasibility of a larger phase III study to evaluate the safety and efficacy of low-dose anticoagulation compared with therapeutic heparin with regard to thrombotic and bleeding events in patients receiving ECMO. DisclosuresNo relevant conflicts of interest to declare.

Analysis of coagulation related parameters between patients with advanced schistosomiasis cirrhosis and hepatitis B cirrhosis

To analyze the differences of coagulation parameters between patients with advanced schistosomiasis cirrhosis and hepatitis B cirrhosis under different degrees of liver function, so as to provide the evidence for further guidance of judging clinical condition and prognosis. Sixty-three patients with advanced schistosomiasis cirrhosis and eighty patients with hepatitis B induced cirrhosis hospitalized in Jingzhou Central Hospital from January 2014 to June 2016 were served as an advanced schistosomiasis cirrhosis group and a hepatitis B cirrhosis group, respectively, and ninety-six gastropathy patients excluded from other diseases that might affect coagulation in the same period were served as a control group. The levels of PT, INR, Fib, TT, APTT, and PLT of the patients among the above 3 groups and the cirrhosis patients with different Child-Pugh classes were detected and compared. The differences of the levels of PT, INR, Fib, TT, APTT, and PLT among the 3 groups were statistically significant (F = 84.512, 81.672, 37.612, 104.475, 52.497, 102.233; all P ＜0.05). The further analysis showed that PT, INR, TT, and APTT of both the advanced schistosomiasis cirrhosis and hepatitis B induced cirrhosis groups were longer than those of the control group, and the PLT levels of both the former 2 groups were lower than that of the control group (all P < 0.05). Compared with the advanced schistosomiasis cirrhosis group, PT, INR, TT, and APTT of the hepatitis B induced cirrhosis group were longer, and the levels of Fib and PLT were lower (all P < 0.05). Among those with the liver function of Grade A, the reduced degree of PLT in the patients with hepatitis B induced cirrhosis was more serious, while for those with the liver function of Grade B and C, the difference between the patients with advanced schistosomiasis cirrhosis and hepatitis B induced cirrhosis was not statistically significant (both P > 0.05). Under all the grades of liver function, TT and APTT of the hepatitis B induced cirrhosis group was longer than those of the advanced schistosomiasis cirrhosis group, and the Fib level of the former was lower than that of the latter. Among those with the liver function of Grade A and B, PT and INR of the hepatitis B induced cirrhosis group were longer than those of the advanced schistosomiasis cirrhosis group; while for those with the liver function of Grade C, the difference between the two groups was not statistically significant (all P > 0.05). There exist differences of the damage degrees of coagulation function between the patients with advanced schistosomiasis cirrhosis and hepatitis B cirrhosis. When the damage degree of the liver function is lighter, the coagulation function in the patients with hepatitis B cirrhosis decreases more significantly; when the damage degree becomes more severe, APPT in the patients with hepatitis B cirrhosis extends more significantly, while the differences of PLT and PT between them are little.

A combined approach using global coagulation assays quickly differentiates coagulation disorders with prolonged aPTT and low levels of FVIII activity.

Patients with mild/moderate hemophilia (H)A, acquired HA (AHA) and lupus anticoagulants (LA), have prolonged aPTTs with low levels of factor (F)VIII activity, but the differentiation of these disorders is complex and time consuming. We established an approach to quickly differentiate these disorders using comprehensive coagulation tests. Patients' plasmas with mild/moderate HA, AHA, LA without anti-phospholipid syndrome [LA-APS(-)], and LA with APS [LA-APS(+)] were examined using clot waveform analysis (CWA) and thrombin generation test (TGT). Activated protein C (APC) sensitivity was assessed by TGT. CWA revealed similarly prolonged clot times in all groups [NP/mild/moderate HA/AHA/LA-APS(-)/LA-APS(+); 33±1/82±12/116±44/90±29/96±15s] but significantly different decreased maximal coagulation velocity (3.1±0.1/1.3±0.3/0.9±0.5/1.6±0.3/2.2±0.5). In TGT, AHA group demonstrated severely reduced peak-thrombin levels (362±23/170±27/49±21/158±75/158±99nM), whilst both LA groups markedly prolonged lag times (4.5±0.3/5.0±0.4/4.7±0.8/12.5±7.7/28.8±11.8min), suggesting that AHA could be readily identified, but the different LA sub-types failed to be classified. An APC sensitivity demonstrated that 'normalized' APC-induced levels of peak thrombin in LA-APS(+) were significantly lower relative to LA-APS(-) (normalized %inhibition; 5±7/42±39%). Our studies confirmed that %inhibition by APC was significantly decreased in NP preincubated with purified IgGs from LA-APS(+) compared to LA-APS(-), facilitating differentiation between LA groups. A combined approach using CWA and TGT could be a useful means of differentiating coagulation disorders with prolonged aPTT.

EFFECT OF DIABETES MELLITUS TYPE II ON ACTIVATED PARTIAL THROMBOPLASTIN TIME AND PROTHROMBIN TIME

Diabetes mellitus contributes for initiation and progression of micro vascular and macro vascular complications. Complication includes coagulation impairment however Shortened activated partial thromboplastin time (aPTT) values may reflect hypercoaguable state, which is associated with increased thrombotic risk and adverse cardiovascular events. Objective : The present study was conducted to study the aPTT and PT levels in patients with diabetes mellitus type II. Material and method : A sample of 50 persons were selected, 30 patients suffering from DM as type II from Al-wahda teaching hospital, Derna-Libya. At the same time a group of 20 randomly selected healthy adults to participate in the study as control group. Result : The mean value of APTT in T2DM individuals was significant lower (28.95 ±7.54) seconds as compare with control, (34.12±2.82) seconds (P = 0.06). The mean value of prothrombin time (PT) among T2DM individuals was (14.04 ±2.96) seconds and the mean value of PT among healthy individuals was (13.5 ± 1.54) seconds. There was no significant difference in PT of T2DM individuals P ≥ 0.05. Conclusion: From this study, it may be concluded that shorted APTT confirms that T2DM is a hyper-coagulable state due to which there is increased risk of thrombotic events.

Changes in some coagulation parameters among male cigarette smokers in Southern Nigeria

Background: Cigarette smoking is a major public health problem globally. In view of this complexity, cigarette smoke has multiple diverse effects on human health and the coagulation system. These effects have not been adequately explored in our population and among Africans with increasing high rate of smoking. Aim: This study was conducted to determine and compare the association between the duration of cigarette smoking and coagulation parameters (prothrombin time and activated partial thromboplastin time) in male cigarette smokers living in Calabar. Materials and Methods: This is a prospective comparative study that which compared the levels of PT and APTT in 106 male smokers and 83 non-smokers which were used as control participants. Cigarette smokers were further divided into two groups based on the number of cigarette sticks smoked per day, mild smokers, those who smoked 1-19 sticks per day and heavy smoker, those who smoked 20 sticks and above per day. Whole blood was dispensed into a trisodium citrate bottle; PT and APTT were quantified using kits from Giesse Diagnostics Italy. The methods were controlled and validated using Giesse control reagents from the manufacturer. Results: The mean PT and APTT for the male smokers were; 11.7+ 0.9secs and 28.7 + 2.9secs respectively. These values were significantly lower than those of the non-smokers with PT and APTT of 13.03 + 0.9secs and 29.8 + 3.4secs (P<0.05). A significant negative correlation was observed between duration of smoking, PT and APTT in the male smokers (P<0.05). There was also a negative correlation between the no of sticks smoked per day and PT in male smokers (r = 0.212). Conclusion: Findings from this study indicate that cigarette smokers are at a high risk of developing clotting problems compared to non-smokers if appropriate interventions are not considered.

Development of PEG-PLGA based Intravenous Low Molecular Weight Heparin (LMWH) Nanoparticles Intended to Treat Venous Thrombosis.

Anticoagulant therapy is effective in the treatment of DVT. In this regard, LMWH demonstrated significant promise. It is widely used clinically. The goal of this study was to prepare and evaluate intravenous sustained release stealth nanoparticles encapsulating LMWH using PLGA (polylactidecoglycolide) and different grades of PEG (poly ethylene glycols). The nanoparticles were prepared using w/o/w solvent evaporation technique. Prepared nanoparticles were evaluated for particle size, encapsulation efficiency, in-vitro drug release, anti-thrombotic activity in venous thrombosis rat model, estimation of aPTT, tissue bio-distribution studies and stability. Scanning electron microscopy (SEM) and Transmission electron microscopy (TEM) studies confirmed the formation of smooth spherical particles. FTIR study reveals successful coating of PEG on the nanoparticles. DSC and XRD results demonstrated that drug changed its physical form in the formulation. The encapsulation efficiency was 63-74%. In vitro drug release was 57-75% for 48 hrs. Macrophage uptake of LMWH with pegylated nanoparticles was less compared to conventional PLGA nanoparticles. In vivo drug release was sustained for 48hrs; Optimized formulation exhibited good enhancement in pharmacokinetic parameters when compared to free drug solution. In vivo sustained release was also demonstrated with antithrombotic activity as well aPTT activity. Optimized formulation demonstrated significant stability, excellent antithrombotic activity in venous thrombosis rat model, improved aPTT levels when compared to free drug solution. An effective stealth LMWH nanoparticle formulation to treat venous thrombosis was successfully developed using w/o/w solvent evaporation technique.

Effect of tripterygium glycosides and Danshen injection on blood coagulation mechanism in children with allergic purpura nephritis

To observe the effect of tripterygium glycosides combined with Danshen injection on blood coagulation mechanism in children with allergic purpura nephritis, and investigate its treatment efficacy through a randomized controlled study. The results showed that before treatment, there were no significant differences in levels of D-D, APTT, PT, FIB and PLT between treatment group and control group; while after treatment, there were significant differences in levels of D-D, PT, FIB and PLT between two groups, but no difference in level of APTT. The effective rate was 90.38% in treatment group, significantly higher than 79.25% in the control group. There was no significant difference in incidence of adverse reactions between two groups. The results suggested that tripterygium glycosides combined with Danshen injection can enhance treatment efficacy and improve blood coagulation mechanism of children in the treatment of purpura nephritis, with high safety and no adverse effects.

Pathogenesis analysis and prevention and treatment of limb deep venous thrombosis complicated by postoperative gynaecological malignant tumours

Objective To analyze the pathogenesis and prevention and treatment of limb deep venous thrombosis complicated by postoperative gynaecological malignant tumours. Methods A retrospective analysis of 22 cases with limb deep venous thrombosis complicated by postoperative gynaecological malignant tumours in our hospital were analyzed.According to the situation of patients, surgery or conservative treatment was conducted.The clinical efficacy after treatment was observed. Results In 22 cases, 6 cases underwent surgical treatment, 16 cases underwent conservative treatment.After treatment, 18 cases were cured, 3 cases were effective, 1 case ineffective.After treatment, the TT, Pt, APTT and FBG levels were (24.17±2.13)s, (18.25±2.13)s, (31.68±10.30)s and (2.26±0.52)g/L, which were all better than before treatment, the differences were statistically significant(t=10.362, 9.774, 12.281, 8.462, P=0.028, 0.032, 0.012, 0.029). Followed up for 3 months, no recurrence of LDVT was observed. Conclusion The cases of gynecological malignant tumor have higher risk of limb deep vein thrombosis, we should taken prevention actively, once diagnosed should take effective intervention measures to improve the prognosis. Key words: Gynecological malignant tumor; Limb deep venous thrombosis; Pathogenesis; Prevention; Treatment

Anaesthesia Management of a Patient with Factor XI Deficiency

Factor XI deficiency is an extremely rare disease presenting no clinical symptoms, unless there is an inducing reason such as trauma or surgery. Normally, factor levels are in the range of 70-150 U dL-1 in healthy subjects. Although no clinical symptoms are seen, only high levels of aPTT can be found. Once a prolongation is detected in aPTT, factor XI deficiency should be suspected and factor levels should be analysed. With careful preoperative preparations in factor-deficient people, preoperative and postoperative complications can be decreased. In this case report, management of anaesthesia during total hip arthroplasty of a patient with factor XI deficiency is presented.

Controlled continuous systemic heparinization increases success rate of artery-only anastomosis replantation in single distal digit amputation: A retrospective cohort study.

Replantation is a prime indication for distal digital amputation, as it helps restore hand aesthetics and functions; however, venous anastomosis is often not feasible. Previous studies used systemic anticoagulation in distal digital artery only anastomosis replantation surgery to improve replantation success rate, however, which yielded limited level of clinical evidence. This study aimed to compare controlled continuous heparinization (CCH) and intermittent bolus heparinization (IBH) for surgical outcome and clinical variables after single distal digital artery only anastomosis replantation surgery.A single-institution, retrospective cohort study was performed. Out of 324 patients who underwent digital replantation surgery, we focused the study for the Zone I and II single distal digital amputation patients excluding confounding factors. Sixty-one patients were included in this study and underwent artery-only anastomosis replantation surgery with postoperative CCH (34 patients) or IBH (27 patients) protocols. The CCH group targeted activated partial thromboplastin time (aPTT) at 51 to 70 seconds, monitoring aPTT levels every eight hours and administering 100 mg of aspirin per day. The IBH group received 300 mg of aspirin per day and underwent IBH (12,500 U). Both groups received intravenous prostaglandin E1 drips (10 μg). To verify the factors affecting the success rate of the heparin protocol, patient factors, clinical factors, and operative factors were extracted from the medical records. Statistical analysis with inverse probability of treatment weights propensity score methods compared treatment outcomes and clinical variables.The CCH group's replantation success rate was higher (91.17% vs 59.25%), and the transfusion rate was increased (P = 0.032). However, the significant decrease in hemoglobin levels (>15%) did not differ between the groups (P = 0.108). Multivariable logistic regression analysis with potent univariate variables (P < .10) revealed that CCH was a statistically significant variable in replantation success rate (P = 0.004). Neither the major bleeding complications nor the significant decrease in patients' platelet levels were observed in both groups.Our study suggests that CCH after artery-only anastomosis replantation surgery in Zone I and II distal digital replantation is a safe method to improve the replantation success rate and may provide a guideline for use of the anticoagulation method following artery-only anastomosis distal digital replantation surgery.

Evaluation of coagulation tests before newborn circumcision: is it necessary?

Evaluation of coagulation parameters prior to newborn circumcision is routinely performed in many countries. However, the value of this screening in predicting the bleeding risk is unknown. The aim of this study was to evaluate the correlation between the preoperative prolonged prothrombin time (PT), activated partial thromboplastin time (aPTT) and excessive bleeding after the circumcision in term, healthy newborns without family history of coagulopathy. The medical records of healthy, full term newborns born at VKV American Hospital, in Istanbul, Turkey, between 2009 and 2012 who were circumcised within the first week of life, were reviewed retrospectively. The data for family history of coagulopathy, clinical sign(s) of bleeding during and/or after delivery, preoperative PT, aPTT levels and the amount of bleeding after circumcision were gathered. The most recent medical records of the patients' were also reviewed for any possible, lately diagnosed bleeding disorder. A total of 450 newborns met the above criteria. None had a family history of bleeding disorder or clinical bleeding. A total of 158 (35%) newborns had an aPTT result greater than 54.5 s, 269 (59%) had PT result greater than 15.9 s and 72 (16%) had international normalized ratio result greater than 1.62. Neither of the patients with prolonged PT and/or aPTT had prolonged or excessive bleeding. The evaluation of PT and aPTT before elective newborn circumcision is not necessary in the absence of clinical bleeding or a family history of bleeding disorder. It is rather a habit in general practice and possibly a result of defensive medicine.

Anticoagulation in Patients With Cirrhosis

To review current literature for anticoagulation in patients with cirrhosis and provide a summary of the effects of cirrhosis on the coagulation cascade, therapeutic monitoring through interpretation of antifactor Xa (anti-Xa), activated partial thromboplastin time (aPTT), and international normalized ratio (INR) as well as current prophylaxis and treatment recommendations in cirrhotic patients. A systematic electronic literature search was conducted in PubMed using the key termsanticoagulation, warfarin, low-molecular-weight heparin(LMWH),unfractionated heparin(UFH),target-specific oral anticoagulants, deep-vein thrombosis(DVT),pulmonary embolism(PE),portal vein thrombosis(PVT),venous thromboembolism, anti-Xa, activated partial thromboplastin time, anticoagulation therapeutic monitoring, coagulopathy, coagulation cascade, chronic liver disease, cirrhosis, anddecompensated liver disease Studies written in the English language from January 2000 to December 2015 were considered for this review article. All search results were reviewed, and the relevance of each article was determined by authors independently. Patients with cirrhosis are at higher risk for both bleeding and thrombosis-related complications. Cirrhosis affects production of both procoagulant and anticoagulant factors, thus resulting in increased INR and aPTT levels and decreased anti-Xa levels. LMWH is the treatment of choice for the prevention and treatment of DVT/PE/PVT in patients with cirrhosis, and monitoring with anti-Xa levels for dose adjustment is not recommended. UFH is an alternative in cirrhotic patients for shorter-term use and in cases of severe renal dysfunction and/or hemodynamic instability. Cirrhotic patients on anticoagulation therapy should be monitored closely for signs and symptoms of bleeding and thrombosis.

Does the course of laboratory parameters help us to predict the outcome of CCHF?

This study was performed to identify the characteristics distinguishing fatal and nonfatal cases of patients diagnosed with Crimean-Congo hemorrhagic fever (CCHF). A total of 92 patients with confirmed diagnosis of CCHF in 2009-2013 were included in the study. A high level of urea and aPTT on the third day of hospital stay, diarrhea, somnolence, and the interval from the beginning of the symptoms to hospital admission were independently associated with fatality. Each 10-unit increase in aPTT and urea levels increased the fatality rate by 3.379-fold and 1.236-fold, respectively. Delay in hospital admission increased the fatality rate 1.453-fold for each day of delay. When comparing first and third admission-day laboratory values, the increase in leukocyte counts and the decrease in CPK, urea, creatinine, aPTT, PT, INR, and hemoglobin levels were significant in nonfatal cases. This study showed that the course of these laboratory tests helps us to predict the outcome of the disease. In a few days of hospitalization, persistence or progress of the abnormal laboratory parameters may warn us about poor prognosis.

Importance of fibrinogen in dilutional coagulopathy after neurosurgical procedures: A descriptive study.

Background and Aims:The routine management of coagulopathy during surgery involves assessing haemoglobin, prothrombin time (PT), activated partial thromboplastin time (aPTT) and platelets. Correction of these parameters involves administration of blood, fresh frozen plasma and platelet concentrates. The study was aimed at identifying the most common coagulation abnormality during neurosurgical procedures and the treatment of dilutional coagulopathy with blood components.Methods:During 2 years period, all adult patients undergoing neurosurgical procedures who were transfused two or more units of red cells were prospectively evaluated for the presence of a coagulopathy. PT, aPTT, platelet count and fibrinogen levels were estimated before starting a component therapy.Results:After assessing PT, aPTT, platelet count and fibrinogen levels following two or more blood transfusions, thirty patients were found to have at least one abnormal parameter that required administration of a blood product. The most common abnormality was a low fibrinogen level, seen in 26 patients; this was the only abnormality in three patients. No patient was found to have an abnormal PT or aPTT without either the fibrinogen concentration or platelet count or both being low.Conclusion:Low fibrinogen concentration was the most common coagulation abnormality found after blood transfusions for neurosurgical procedures.

Atypical Haemolytic Uraemic Syndrome Associated with Cabazitaxel in Advanced Prostate Cancer

Atypical haemolytic uraemic syndrome, (aHUS) is a rare but potentially lifethreatening condition with clinical manifestations of haemolytic anaemia, thrombocytopenia, and renal failure. We report the first case of aHUS secondary to cabazitaxel in the setting of metastatic castrate resistant prostate cancer. In July 2015, a 73 year old male presented with acute on chronic back pain, in the context of metastatic castrate-resistant prostate cancer with known pulmonary and skeletal metastases. He was day 3 into his first cycle of cabazitaxel. Within 24 hours of admission, he acutely deteriorated with progressive drowsiness and the development of an acute kidney injury. During this period, he developed acute thrombocytopenia, falling to 58 x 109/L and haemolytic anaemia. He had a coagulopathy, with an elevated INR 1.5, but with a normal APTT and fibrinogen levels. He was subsequently diagnosed with an atypical haemolytic uraemic syndrome. In light of his rapid decline and poor prognosis he was managed with conservative treatment. Over the next 24 hours, he developed progressive acute renal failure and ongoing haemolysis. There was further neurological deterioration which culminated in his passing away three days following his initial presentation. With the

DIC and Its Association with Acute Leukemia in Pre-Treatment and Post Remission Induction Phase

Background:Hematological malignancy like acute leukemia (AL) is associated with thromboembolic complications.DIC is a worst complication amongst subtypes of AL especially in APML which can be life threatening.Study design:Descriptive & cross-sectional study.Place and duration of study:National Institute of Blood Disease and Bone Marrow Transplantation; May 2011 to March 2012.Patients and methods:110 (75 males, 45 females)diagnosed cases of acute leukemia [43 cases of AML (27 newly diagnosed, 16 in remission induction), 67 cases of ALL (38 newly diagnosed; 29 in remission induction)]were included & 40 ascontrols.Mean age of patients was 25.3±13.8.Platelet count,PT, APTT, Fibrinogen levels, D-Dimer &FDP was done for scoring of DIC on day 0 and 28. SPSS version 17 was used for data analysis.Results:Platelet counts significantly improved on day 28 in AML and ALL. PT and APTT levels were significantly deranged. Plasma levels of fibrinogen were higher in both types of acute leukemia in pre-treatment phase, further increased at day 28 (<0.01). FDP significantly raised at day 0 reduced at day 28(AML & ALL). Markedly elevated levels of D-dimer in AML and ALL at day 0,but showed significant reduction at day 28(<0.01). DIC score of <5 was found in 15 (55.56%) patients of AML and 16 (100%) of ALL on day 0 and >5 score was recorded in 12(44.44%) patients of AML on day 28.Conclusion:Strong association of DIC was found in AML and ALL at day 0. Non overt DIC did not show any significant association with specific type of acute leukemia and it was equally expressed in both type of acute leukemia at day 0 and 28. DisclosuresNo relevant conflicts of interest to declare.

Autosomal Recessive Inherited Bleeding Disorders in Pakistan, a Cross Sectional Study from Selected Regions

INTRODUCTION: Incidence of autosomal recessive disorders is rare, includes deficiencies of clotting factors I, II, V, VII, X, XI, XIII, vitamin K dependent clotting factors, combined factor V & VIII, Von Willebrand disease type 3, Glanzmann Thrombasthenia and Bernard Soulier syndrome.OBJECTIVE: Spectrum of autosomal recessive bleeding disorders (ARBDs] among Pakistani patients.PATIENTS AND METHODS: This cross-sectional study was carried out at Karachi, Lahore, Islamabad and Peshawar. PT,aPTT, BT, and fibrinogen levels done. Patients with prolonged APTT were tested for factors VIII and IX. If FVIII was low, von Willebrand factor: antigen (vWF: Ag) and von Willebrand factor: ristocetin cofactor (vWF: RCo) were performed. When PT and aPTT both were prolonged, FII, FV, and FX were tested. Peripheral film and platelet aggregation studies were done for platelet disorders. Urea clot solubility test was done at the end.RESULTS: Out of429 patients, 148 were diagnosed with Hemophilia A, remaining 281 patients had ARBDs. 95 (33.8%) had VWD type 3. Fibrinogen deficiency was found in 34 (12%), Glanzmann Thrombasthenia in 27 (9.6%), factor XIII in 13 (4.6%), factor VII in 12 (4.3%), factor V in 9 (3.2%), 8 (2.8%) in vitamin K dependent clotting factors, , Bernard Soulier in 7 patient (2.5%),factor X in 2 (0.7%), factor II in 2 (0.7%), factor XI and combined factor V and VIII in 1 (0.4%)patients each. 70 patients (16.3%) remained undiagnosed.CONCLUSION: VWD type 3 is the most common deficiency followed by fibrinogen deficiency. Glanzmann thrombasthenia was the third most common ARBD. DisclosuresNo relevant conflicts of interest to declare.

Identification of Molecular Defects in ITGA2B and ITGB3 Genes and Phenotypic Correlation in Pakistani Patients with Glanzmann Thrombasthenia

Background:Glanzmann thrombasthenia (GT) is most common inherited platelet functional defect. It is an autosomal recessive disorder, characterized by a bleeding diathesis. Incidence is increased in locations where consanguineous marriages are common. The defect is caused by mutations in the genes encoding ITGA2B or ITGB3. This results in qualitative or quantitative abnormalities of the platelet receptor, αIIb-β3 integrin.Objectives:The aim of this study was to identify and correlate the mutations in GT patients with phenotype of the patient.Subjects and methods:20 patients with GT were enrolled in the study to identify the molecular defects and to correlate their phenotype with their genotype. CBC with peripheral film, PT, APTT and Fibrinogen levels were done initially. Platelet aggregation studies, flow cytometry, and mutation analysis was done by Sanger sequencing. Genomic DNA was extracted from peripheral blood by QIAamp DNA Blood mini kit (Qiagen) and Exon specific PCR was done for GT gene and Direct gene sequenced on automated ABI-3130 Genetic Analyzer (Applied Biosystems). For any variation wild type was matched on HGMD (Human Gene Mutation Database http://www.hgmd.cf.ac.uk/ac/index.php) and wild type color fasta sequence (http://pga.gs.washington.edu/). Pathogenecity score was evaluated by using software tools including :Polyphen-2(http://genetics.bwh.harvard.edu/pph2/) ,SNP&GO(http://snps.biofold.org/snps-and-go/index.html), MUpro (http://mupro.proteomics.ics.uci.edu/) ,SIFT (http://sift.jcvi.org), Provean (http://provean.jcvi.org/about.php) .All samples were sequenced at the Gene Sequencing Lab of NIBD (National Institute of Blood diseases and Bone Marrow Transplantation) Karachi.Results:Mutations were identified in all patients. Missense mutations were seen in most of the GT patients. The remaining mutations were heterogeneous and were distributed throughout the length of the gene.Conclusions:The severe type I GT was the most common subtype found in this study.Carrier detection and genetic counseling in these families is a potentially effective alternative for decreasing the burden of severe type of GT. DisclosuresNo relevant conflicts of interest to declare.

Management of Perioperative Anticoagulation in Patients with VWD

▪Objectives: von Willebrand disease (VWD) is the most common hereditary bleeding disorder. This study reviews the management of perioperative anticoagulation in patients with VWD undergoing surgical procedures. Risk factors for VTE with von Willebrand factor (VWF) concentrate use are older age, previous VTE, obesity, surgery, hormone replacement therapy use, antifibrinolytic therapy use and high post infusion FVIII levels. Currently, there are few data from randomized clinical trials assessing efficacy and possible complications of perioperative VTE prophylaxis in VWD patients.Methods: A total number of 116 surgeries were performed (minor: n=64 and major: n=52) in this retrospective, single-centre study. They were divided into groups of perioperative non-anticoagulation (n=54) and perioperative anticoagulation (n=62), who all received coagulation factor concentrate (CFC). Sub-analyses were done according to the type of concentrate used. Anticoagulation was performed using different low molecular weight heparins (LMWH) according to standard protocols or body-weight adapted doses in patients with either elevated body-mass-index or additional thrombosis risk factors. Blood samples had been collected pre- and post-surgery (up to 21 days) to analyse PT, aPTT, PFA, and trough levels of FVIII coagulant activity (FVIII:C), VWF activity (VWF:GPIbM) and antigen (VWF:Ag), respectively. Furthermore, the median doses of CFC/kg and the median total number of infusions were calculated. The rates of clinically overt thrombosis as well as bleeding were assessed during the post-operative phase.Results: The majority of patients suffered from VWD type 1 (104), 9 patients with type 2A, 2 with type 2M and 1 with type 3 VWD. Humate-P (H) was used in 55 patients and 61 patients received Wilate (W). Using W, we found parallel curves for FVIII:C, VWF-antigen and VWF:GPIbM, respectively. Using H, less concordance between VWF:Ag and VWF:GPIbM was visible and FVIII:C tends to increase between D3 to D10 in spite of decreasing VWF:Ag and VWF:GPIbM. This observation was visible in minor as well as major surgical procedures. LMWH (Enoxaparin, Nadroparin and Certaparin) were used in doses between 30 and 100 mg/injection (mean 46.0 ± 18.5 mg/injection) and a mean of 32.2 ± 24.6 injections in total (range: 8-112). In one patient a significant haematoma occurred (1/116; 0.9%), also one thrombotic event was documented in a different patient (1/116; 0.9%).Conclusion: Using standard dose LMWH in patients with no overt increased thrombosis risk as well as body-weight-adapted LMWH in high risk patients seem to be safe and effective in VWD patients receiving coagulation factor concentrate perioperatively. However, prospective randomized comparative studies are required to determine the optimal indication as well as type of anticoagulation according to the CFC treatment regimen in this setting. DisclosuresNo relevant conflicts of interest to declare.