[Vertebral fractures combined with prolonged activated partial prothrombin time: A case report]

With the development of modern medical standards, autoimmune diseases and their associated successive osteoporosis have received increasing attention in recent years. Patients with autoimmune diseases, due to the characteristics of the disease and the prolonged use of glucocorticoid hormone therapy, may affect the bone formation and bone absorption of the patient, followed by severe successive osteoporosis, thereby increasing the risk of osteoporotic vertebral fractures. Vertebral compression fractures of the spine are common fracture types in patients with osteoporotic fractures. Osteoporosis is a common complication after glucocorticoid therapy in patients with autoimmune diseases. Percutaneous vertebroplasty (PVP) and percutaneous kyphoplasty (PKP) are minimally invasive operation and are commonly used surgical methods for the treatment of osteoporotic vertebral compression fractures. However, due to the operation of spinal puncture during the operation, there are serious surgical risks such as bone cement leakage, spinal epidural hemorrhage, subdural hemorrhage, and subarachnoid hemorrhage in both PVP and PKP. As a result, it is necessary to evaluate the patient' s body before surgery carefully, especially in the case of blood coagulation. This article reports a case of autoimmune disease patient admitted to Peking University People' s Hospital due to lumbar 4 vertebral compression fracture combined with Sjögren' s syndrome. The patient' s preoperative examination showed that the activated partial thromboplastin time (APTT) was significantly prolonged. After completing the APTT extended screening experiment and lupus anticoagulant factor testing, the multi-disciplinary team (MDT) of Peking University People' s Hospital jointly discussed the conclusion that the patient' s test results were caused by an abnormal self-immunity anti-copulant lupus (LAC). Based on the results of the laboratory examination, the patient was considered to be diagnosed with combined antiphospholipid syndrome (APS). For such patients, compared with the patient' s tendency to bleed, we should pay more attention to the risk of high blood clotting in the lower limbs of the patient, pulmonary clots and so on. With timely anti-coagulation treatment, the patient safely passed the peripheral period and was successfully discharged from the hospital. Therefore, for patients with autoimmune diseases with prolonged APTT in the perioperative period, doctors need to carefully identify the actual cause and carry out targeted treatment in order to minimize the risk of surgical and perioperative complications and bring satisfactory treatment results to the patients.

Head-to-head ex vivo comparison of clinically used direct anticoagulant drugs

An imbalance in coagulation is associated with cardiovascular events. For prevention and treatment, anticoagulants, currently mainly xabans and gatrans, are used. The purpose of the present study was to provide a head-to-head comparison since there are no studies directly evaluating these novel anticoagulants. An additional aim was to find whether selected anthropological and biochemical factors can affect their anticoagulant properties as they are used in fixed doses. In this cross-sectional study, blood from 50 generally healthy donors was collected, and coagulation responses to dabigatran, argatroban, rivaroxaban, and apixaban, at a concentration of 1 μM, were analyzed. Heparin was used as a positive control. Prothrombin time (PT) expressed as international normalized ratio (INR) and activated partial thromboplastin time (aPTT) were measured and compared. Rivaroxaban was the most active according to PT/INR while argatroban according to aPTT. The ex vivo anticoagulant effect measured by INR correlated inversely with body mass index (BMI) in all four anticoagulants tested. Shortening of aPTT was associated with higher cholesterol and triglyceride levels. No sex-related differences were observed in response to the anticoagulant treatments. As this was an ex vivo study and pharmacokinetic factors were not included, the influence of BMI is of high therapeutic importance.

Prognostic value of APTT combined with fibrinogen and creatinine in predicting 28-Day mortality in patients with septic shock caused by acute enteric perforation

BACKGROUND

Septic shock is one of the leading causes of mortality in intensive care units. This retrospective study was carried out to evaluate the association of clinical available factors with 28-day mortality.

PATIENTS AND METHOD

In this observational study, patients with perioperative septic shocks secondary to intra-abdominal infection caused by enteric perforation were included. A total of 328 sepsis patients were admitted to the surgical intensive care units from January 2012 to December 2016. A total of 138 patients met the enrolment criteria and were included in the study. The data of demographic, clinical and laboratory were all recorded.

RESULT

All these 138 patients received abdominal surgery prior to surgical intensive care units caused by acute enteric perforation. These patients were all met the diagnostic criteria of septic shock according to Sepsis-3. Statistical analysis showed that lactic acid, blood platelet, fibrinogen, creatinine and activated partial thromboplastin time were found to be associated with 28-day mortality. A combination of serum activated partial thromboplastin time combined with fibrinogen and creatinine could predict in-hospital 28-day mortality. The area under the curve of serum activated partial thromboplastin time combined with fibrinogen and creatinine is 0.875 (0.806-0.944).

CONCLUSION

In conclusion, this pilot study demonstrated that these factors can predict the prognosis of septic shock caused by enteric perforation. In order to reduce the mortality, surgeons and intensive care units physician may consider these data in perioperative period.

Relevant detection indicator of prethrombotic state in patients with primary hypertension

BACKGROUND

Hypertension is a common chronic disease that affects many people worldwide. Only a few reports related to the exploration of relevant indicators of the prethrombotic state in patients with primary hypertension (PH) in clinical settings were available.

AIM

To detect prethrombotic state-related indicators in patients with PH and analyze their differences in different patient populations to provide a laboratory basis for the clinical prevention and control of hypertensive thrombotic diseases.

METHODS

The general data of patients with PH who attended the Department of Cardiovascular Medicine, The First Affiliated Hospital of Jiangxi Medical College, from January 2022 to December 2022 were collected retrospectively. The patients were divided into three groups of 40 patients each according to the Grade of PH: Grade 1, Grade 2, and Grade 3 hypertension experimental group. The baseline data of 40 volunteers, who underwent physical examination in our hospital but were not diagnosed with PH during the same period, were included in the control group. The relevant indicators of prethrombotic state of the participants were compared, and mainly included inflammation-related indicators, hemorheology-related indicators, and coagulation function related indicators. The relationship between the aforementioned indicators and the progression of PH was analyzed.

RESULTS

No significant differences were observed in age, sex, diabetes mellitus, smoking history, drinking history, body mass index, New York Heart Association functional classification, or the course of hypertension among the four groups (P > 0.05). The expressions of high-sensitivity C-reactive protein (hs-CRP), thrombomodulin (TM), hematocrit (Hct), erythrocyte sedimentation rate (ESR), P-selectin on platelet surface (CD62P), and fibrinogen (FIB) in the control group were < Grade 1 hypertension group < Grade 2 hypertension group < Grade 3 hypertension group, and the expressions of platelet (PLT), activated partial thromboplastin time (APTT), prothrombin (PT), and plasma thrombin time (TT) in the control group was > Grade 1 hypertension group > Grade 2 hypertension group > Grade 3 hypertension group, and the difference was statistically significant (P < 0.05). The results of the multivariate logistic regression model showed that the expression of hs-CRP, TM, Hct, ESR, CD62P, PLT, APTT, PT, TT, and FIB in the included participants was related to the progression of PH. Among these, high expression of hs-CRP, TM, Hct, ESR, CD62P, APTT, PT, and TT, and low expression of PLT and FIB were risk factors for PH (OR > 1, P < 0.05). The results of the receiver operating characteristic curve analysis showed that the area under the curve of hs-CRP, TM, ESR, CD62P, APTT, PT, TT, and FIB for the prediction of PH were > 0.80, and the prediction value was ideal. Linear correlation analysis with bivariate Spearman showed that hs-CRP, TM, Hct, ESR, CD62P, APTT, PT, and TT were positively correlated with each other (r > 0, P < 0.05); PLT and FIB were negatively correlated with hs-CRP, TM, Hct, ESR, CD62P, APTT, PT, and TT (r < 0, P < 0.05); and PLT and FIB were positively correlated (r > 0, P < 0.05). Linear correlation analysis using bivariate Spearman showed that hs-CRP, TM, Hct, ESR, CD62P, and FIB were positively correlated with each other (r > 0, P < 0.05), whereas PLT, APTT, PT, and TT were negatively correlated with hs-CRP, TM, Hct, ESR, CD62P, and FIB (r < 0, P < 0.05). There was a positive correlation between PLT, APTT, PT, and TT (r > 0, P < 0.05).

CONCLUSION

The relevant indicators of the prethrombotic state in patients with PH, such as hs-CRP, TM, Hct, ESR, CD62P, PLT, APTT, PT, TT, and FIB, showed differences. High expression of hs-CRP, TM, Hct, ESR, CD62P, and FIB, and low expression of PLT, APTT, PT, and TT are the keys to the occurrence, progression, and thrombotic state of PH. Based on the above serum indicators' expression in patients, targeted interventions can be administered to patients with abnormal expression levels to control the progression of their disease and reduce the risk of developing a prethrombotic state.

Systemic anticoagulation in ECMO

While unfractionated heparin (UFH) remains the mainstay of anticoagulation during pediatric extracorporeal life support, direct thrombin inhibitors (DTIs) are increasingly used. In this article, we will review most recent evidence regarding utilization of both UFH and DTIs and compare their known advantages and disadvantages. We will present anticoagulation monitoring strategies during ECMO and outline the most recent Extracorporeal Life Support Organization's anticoagulation guidelines, however with the caveat that there are no true consensus recommendations for anticoagulation management in pediatric ECMO. With these updates, we will serve as the bedside clinician's refresher on common practices for anticoagulation during "routine" ECMO. We will additionally highlight special circumstances, including high risk surgical procedures during ECMO, in which adjustments in anticoagulation and/or addition of antifibrinolytic therapy might mitigate risk.

Clinical association between coagulation indicators and bone metastasis in patients with gastric cancer

BACKGROUND

Bones are one of the most common target organs for cancer metastasis. Early evaluation of bone metastasis (BM) status is clinically significant. Cancer patients often experience a hypercoagulable state.

AIM

To evaluate the correlation between coagulation indicators and the burden of BM in gastric cancer (GC).

METHODS

We conducted a single-center retrospective study and enrolled 454 patients. Clinical information including routine blood examination and coagulation markers were collected before any treatment. Patients were grouped according to the status of BM. Receiver operating characteristic curves were used to assess diagnostic performance and determine the optimal cutoff values of the above indicators. Cutoff values, sensitivity and specificity were based on the maximum Youden index. Univariate and multivariate logistic regression analyses were used to evaluate the relationships between biomarkers and BM.

RESULTS

Of the 454 enrolled patients, 191 patients were diagnosed with BM. The receiver operating characteristic curve analysis suggested that prothrombin time (PT) [cutoff: 13.25; sensitivity: 0.651; specificity: 0.709; area under receiver operating characteristic curve (AUC) = 0.738], activated partial thromboplastin time (aPTT) (cutoff: 35.15; sensitivity: 0.640; specificity: 0.640; AUC = 0.678) and fibrin degradation products (FDP) (cutoff: 2.75; sensitivity: 0.668; specificity: 0.801; AUC = 0.768) act as novel predictors for BM. Based on multivariate logistic regression analysis, the results showed the independent correlation between PT [odds ratio (OR): 3.16; 95% confidence interval (CI): 1.612-6.194; P = 0.001], aPTT (OR: 2.234; 95%CI: 1.157-4.313; P = 0.017) and FDP (OR: 3.17; 95%CI: 1.637-6.139; P = 0.001) and BM in patients with GC. Moreover, age, carcinoembryonic antigen, erythrocyte and globulin were found to be significantly associated with BM.

CONCLUSION

Coagulation markers, namely PT, aPTT and FDP, might be potential predictors for screening BM in patients with GC.

aPTT-guided anticoagulation monitoring during ECMO support: A systematic review and meta-analysis

INTRODUCTION

The initiation of the extracorporeal membrane oxygenation (ECMO) is associated with complex coagulatory and inflammatory processes and consequently needed anticoagulation. Systemic anticoagulation bears an additional risk of serious bleeding, and its monitoring is of immense importance. Therefore, our work aims to analyze the association of anticoagulation monitoring with bleeding during ECMO support.

MATERIAL AND METHODS

Systematic literature review and meta-analysis, complying with the PRISMA guidelines (PROSPERO-CRD42022359465).

RESULTS

Seventeen studies comprising 3249 patients were included in the final analysis. Patients experiencing hemorrhage had a longer activated partial thromboplastin time (aPTT), a longer ECMO duration, and higher mortality. We could not find strong evidence of any aPTT threshold association with the bleeding occurrence, as less than half of authors reported a potential relationship. Finally, we identified the acute kidney injury (66%, 233/356) and hemorrhage (46%, 469/1046) to be the most frequent adverse events, while almost one-half of patients did not survive to discharge (47%, 1192/2490).

CONCLUSION

The aPTT-guided anticoagulation is still the standard of care in ECMO patients. We did not find strong evidence supporting the aPTT-guided monitoring during ECMO. Based on the weight of the available evidence, further randomized trials are crucial to clarify the best monitoring strategy.

Predictive value of immunoglobulin G, activated partial thromboplastin time, platelet, and indirect bilirubin for delayed viral clearance in patients infected with the Omicron variant

Background

Omicron is the recently emerged highly transmissible severe acute respiratory syndrome coronavirus 2 variant that has caused a dramatic increase in coronavirus disease-2019 infection cases worldwide. This study was to investigate the association between demographic and laboratory findings, and the duration of Omicron viral clearance.

Methods

Approximately 278 Omicron cases at the Ruijin Hospital Luwan Branch, Shanghai Jiaotong University School of Medicine were retrospectively analyzed between August 11 and August 31, 2022. Demographic and laboratory data were also collected. The association between demographics, laboratory findings, and duration of Omicron viral clearance was analyzed using Pearson correlation analysis and univariate and multivariate logistic regression.

Results

Univariate logistic regression analyses showed that a prolonged viral clearance time was significantly associated with older age and lower immunoglobulin (Ig) G and platelet (PLT) levels. Using multinomial logistic regression analyses, direct bilirubin, IgG, activated partial thromboplastin time (APTT), and PLT were independent factors for longer viral shedding duration. The model combining direct bilirubin, IgG, APTT, and PLT identifies patients infected with Omicron whose viral clearance time was ≥7 days with 62.7% sensitivity and 83.4% specificity.

Conclusion

These findings suggest that direct bilirubin, IgG, PLT, and APTT are significant risk factors for a longer viral shedding duration in patients infected with Omicron. Measuring levels of direct bilirubin, IgG, PLT, and APTT is advantageous to identify patients infected with Omicron with longer viral shedding duration.

Effect of fat emulsion administration on blood coagulation in terminal lung cancer patients

Objectives

Patients with cancer, especially those with lung cancer, are at high risk of developing thrombosis. Intralipos^® infusion 20% is contraindicated for thrombosis, and there is no consensus on whether it can be safely used in cases of advanced cancer. We conducted a retrospective observational study to elucidate the impact of fat emulsion administration on blood coagulation in patients with terminal lung cancer.

Methods

The subjects were patients with terminal lung cancer in the Department of Surgery and Palliative Medicine, Fujita Health University Nanakuri Memorial Hospital between January 2016 and December 2019. We compared changes in their blood coagulation profile before hospitalization and one month later.

Results

There were a total of 213 patients with lung cancer-139 who were administered fat emulsion and 74 who were not-with no significant differences in baseline characteristics. In the fat emulsion administration group (n=27), the prothrombin time-international normalized ratio (PT-INR) and activated partial thromboplastin time (APTT), respectively, were 1.17±0.26 (mean±standard deviation) and 30.5±5.0 s at hospitalization and 1.16±0.12 and 31.2±4.2 s one month later with no significant differences. In the non-administration group (n=6), the PT-INR and APTT, respectively, were 1.44±0.43 and 30.6±5.2 s before hospitalization and 1.28±0.18 and 33.0±7.5 s one month later with no significant differences.

Conclusions

We did not identify any changes in PT-INR and APTT after fat emulsion administration in patients with terminal lung cancer. There were also no new cases of thrombosis, suggesting that fat emulsions were administered safely in patients with terminal lung cancer.

A tumor-selective adenoviral vector platform induces transient antiphospholipid antibodies, without increased risk of thrombosis, in phase 1 clinical studies

Tumor-selective viruses are a novel therapeutic approach for treating cancer. Tumor-Specific Immuno Gene Therapy (T-SIGn) vectors are tumor-selective adenoviral vectors designed to express immunomodulatory transgenes. Prolonged activated partial thromboplastin time (aPTT), associated with the presence of antiphospholipid antibodies (aPL), has been observed in patients with viral infections, and following administration of adenovirus-based medicines. aPL may be detected as lupus anticoagulant (LA), anti-cardiolipin (aCL) and/or anti-beta 2 glycoprotein antibodies (aβ2GPI). No subtype alone is definitive for development of clinical sequalae, however, patients who are 'triple positive' have a greater thrombotic risk. Additionally, isolated aCL and aβ2GPI IgM do not appear to add value in thrombotic association to aPL positivity, rather IgG subtypes must also be present to confer an increased risk. Here we report induction of prolonged aPTT and aPL in patients from eight Phase 1 studies who were treated with adenoviral vectors (n = 204). Prolonged aPTT (≥ Grade 2) was observed in 42% of patients, with a peak at 2-3 weeks post-treatment and resolution within ~ 2 months. Among patients with aPTT prolongation, LA, but not aCL IgG nor aβ2GPI IgG, was observed. The transience of the prolongation and discordance between positive LA and negative aCL/aβ2GPI IgG assays is not typical of a prothrombotic state. Among the patients with prolonged aPTT there was no evidence of an increased rate of thrombosis. These findings elucidate the relationship between viral exposure and aPL in the context of clinical trials. They suggest a framework in which hematologic changes can be monitored in patients receiving similar treatments.Clinical trial registration:NCT02028442, NCT02636036, NCT02028117, NCT03852511, NCT04053283, NCT05165433, NCT04830592, NCT05043714.

Assays to Monitor Bivalirudin

Bivalirudin (Angiomax, Angiox) is a parenteral direct thrombin inhibitor (DTI) that is used for patients with heparin-induced thrombocytopenia (HIT), where heparin cannot be used due to the risk of thrombosis. Bivalirudin is also licensed for use in cardiology procedures (e.g., percutaneous transluminal coronary angioplasty; PTCA). Bivalirudin is a synthetic analogue of hirudin found in the saliva of the medicinal leech and has a relatively short half-life of ~25 min. Several assays can be used to monitor bivalirudin; these include the activated partial thromboplastin time (APTT), activated clotting time (ACT), ecarin clotting time (ECT), an ecarin-based chromogenic assay, thrombin time (TT), the dilute TT, and the prothrombinase-induced clotting time (PiCT). Drug concentrations can also be measured using liquid chromatography tandem mass spectrometry (LC/MS) and clotting or chromogenic-based assays with specific drug calibrators and controls.

The diagnosis and Management of HIV Associated Acquired Hemophilia A: A Case Series From Durban, South Africa

INTRODUCTION

In acquired hemophilia A (AHA), the body produces auto-antibodies against Factor VIII. Although AHA is rare, with an incidence of 1.5 patients/1 million population/year, there is a strong association with human immunodeficiency virus (HIV) infection. The accurate interpretation of screening coagulation tests is critical to identify patients with AHA, as the mortality rate secondary to bleeding is high.

METHODS

This was a retrospective case series which included all newly diagnosed AHA patients that were referred to Hemophilia care unit at King Edward VIII Hospital, Durban, South Africa from January 2011 to December 2021. The clinical presentation and laboratory results were documented.

RESULTS

Five patients were included in this case series. All patients were females aged between 28 and 64 years of age and they were HIV seropositive. They presented with spontaneous cutaneous and intramuscular bleeding. Four patients were virologically suppressed on anti-retroviral therapy, and no patient had a family history of congenital bleeding diathesis. Laboratory investigations confirmed AHA with high Factor VIII inhibitor titers, which ranged from 41 to 900 Bethesda Units (BU). All patients were managed with bypassing agents and oral corticosteroids. The monitoring of patients after the initiation of treatment was difficult as they all defaulted treatment.

CONCLUSION

In view of the prevalence of HIV in sub-Saharan Africa, there is a possibility that AHA is under-diagnosed in our setting. The clinician and the laboratory have a combined critical role in identifying patients with AHA as the investigation of a prolonged APTT is mandatory. There are challenges in managing AHA patients in a resource-constrained setting.

Application of anti-Xa assay in monitoring unfractionated heparin therapy in contemporary antithrombotic management

INTRODUCTION

Unfractionated heparin remains the most widely used agent in the prevention and acute treatment of thrombosis. Pharmacological complexities of this intriguing agent mandate frequent monitoring of its anticoagulant properties to maintain safe and effective hematological outcomes. Although activated partial thromboplastin time has been the standard test to monitor unfractionated heparin therapy for many decades, the anti-Xa assay has emerged as a substitute or adjunct in many institutions.

AREAS COVERED

This brief report outlines the key features of anti-Xa assay in monitoring unfractionated heparin in acute management of thrombosis in various contemporary settings, with emphasis on evidence for clinical outcomes. PubMed.gov database was utilized to obtain the pertinent literature.

EXPERT OPINION

The anti-Xa activity is primarily a reflection of UFH concentration and does not account for other hematological variables frequently present in contemporary anticoagulation management. The advantage of the anti-Xa assay in monitoring UFH therapy is predicated upon its limitations to account for global physiological hemostasis. There are significant disease and drug interactions that may potentially result in false in-vitro analysis of anti-Xa activity. Routine application of the anti-Xa assay is not evidence-based at this time.

Part 1: Analytical results

BACKGROUND

Unexpected prolongation of first-line coagulation tests, including activated partial thromboplastin time (APTT), should trigger further work-up by performing mixing tests to elucidate the underlying cause, direct further specific testing and clarify their possible clinical impact. The aim of our study was to assess whether methodological diversity has any impact on the APTT mixing test results and their interpretation.

MATERIAL AND METHODS

Two lyophilized plasma samples (case 1: heparin contamination [0.5 IU/mL]; case 2: factor VIII deficiency [0.13 IU/mL]) and their respective fictional clinical cases were sent to European laboratories for APTT measurement and performance of mixing tests. Participants were surveyed about the methodology (reagents, analytical platform, reference ranges), APTT results, mixing test conditions, their classification (normal, equivocal, prolonged) and categorization of the sample (factor deficiency, presence of inhibitor, anticoagulant, unknown).

RESULTS

A total of 269 responses were included. For case 1, all participants reported a prolonged APTT, and 91% obtained no correction in the mixing test, without differences among reagents or analytical platforms. Only 15% of them selected the presence of an anticoagulant as the single cause for the prolongation. For case 2, 99% of participants reported a prolonged APTT, while some heterogeneity in the mixing test results was found. Eighty-six percent of participants selected factor deficiency as the cause for APTT prolongation.

CONCLUSIONS

Most European laboratories obtained valid results for APTT and the subsequent mixing tests, despite using different methodologies. However, their classification could be improved. Therefore, more training and periodic evaluations are recommended to harmonize protocols and ensure proper result classification and categorization.

Tigecycline-Associated Coagulopathy: A Single-Center Retrospective Analysis

INTRODUCTION

The purpose of this study was to assess clinical characteristics and risk factors for tigecycline-associated prothrombin time (PT) and activated partial thromboplastin time (aPTT) prolongation.

METHODS

We performed a retrospective analysis on coagulation parameters before and during tigecycline treatment in 55 patients in our hospital with severe infections, mainly pneumonia caused by Acinetobacter baumannii. Patients were divided into different groups according to prolongation of PT and aPTT, and clinical features involved were explored. Univariate and multivariable binary logistic regression analyses were used to identify risk factors for tigecycline-associated PT and aPTT increase.

RESULTS

We found that PT values increased from 12.73 ± 1.87 to 13.86 ± 2.06 during the treatment compared with premedication (p < 0.001), and the aPTT level prolonged significantly from 33.63 ± 11.24 to 38.15 ± 11.81 (p < 0.001). The multivariate analyses identified 2 variables that were associated with tigecycline-induced PT prolongation: albumin level (p = 0.018) and weight-adjusted tigecycline dosage (p = 0.005). In addition, treatment duration was the only risk factor for tigecycline-induced aPTT prolongation (p = 0.043).

CONCLUSION

Albumin level, weight-adjusted tigecycline dosage, treatment duration may serve as risk indicators for tigecycline-associated coagulation dysfunction. Physicians should be careful with coagulation disorder when prescribing tigecycline in clinical practice, especially in patients with risk factors.

[Analysis of risk factors for hemorrhage in patients with acute poisoning treated with hemoperfusion]

Objective: To explore the clinical characterist ics and risk factors of hemorrhage complicated by hemoperfusion therapy in patients with acute poisoning. Methods: In January 2021, the clinical data of 196 patients with acute poisoning who received hemoperfusion therapy in the Second Affiliated Hospital of Air Force Military Medical University from January 2018 to December 2020 were analyzed, and the patients were divided into bleeding group and non-bleeding group according to whether the patients were complicated with bleeding. Multivariate logistic regression was used to analyze the independent risk factors for hemorrhage in patients treated with hemoperfusion. Results: A total of 21 patients in the bleeding group and 175 patients in the non-bleeding group were included. There was no significant difference in general data such as gender, age, and body mass index between the two groups (P>0.05) . Organophosphorus pesticides (χ(2)= 4.56, P=0.030) , HA230 perfusion device (χ(2)=4.12, P=0.042) , platelet count (t=-2.33, P=0.009) and activated partial thromboplastin time (t=14.53, P<0.001) at 2 h of perfusion were the influencing factors of hemorrhage in patients with acute poisoning treated with hemoperfusion. Among them, organophosphorus pesticides, 2 h perfusion activated partial thromboplastin time ≥35 s and other factors were independent risk factors forcomplicated bleeding (P<0.05) . Conclusion: Patients with acute poisoning, especially organophosphorus pesticide poisoning, are at greater risk of bleeding during hemoperfusion therapy. Monitoring of changes in activated partial thromboplastin time should be strengthened and the dose of anticoagulants should be adjusted in time to reduce the risk of bleeding.

Coagulation markers in patients with venous thromboembolism treated with 10 mg apixaban twice daily

Apixaban is used to treat venous thromboembolism (VTE) at 10 mg twice daily (BID) for 7 days, followed by 5 mg BID without dose adjustment, and non-valvular atrial fibrillation (NVAF) at 5 mg BID or 2.5 mg BID with dose adjustment criteria (DAC) including age, body weight, and renal function. The anti-factor Xa activity (AXA), prothrombin time (PT), and activated partial thromboplastin time (APTT) in patients with VTE receiving 10 mg BID of apixaban remains unclear. Twenty-six patients (70.8±15.4 years, 10 males) with VTE receiving 10 mg BID of apixaban were enrolled. The patients were divided into two groups based on whether they met the DAC of NVAF: DAC group (n=8) and non-DAC group (n=18). Trough and peak AXA values, PT, and APTT were measured at 10 mg BID dosage and then at 5 mg BID dosage. Coagulation markers in recipients of 10 mg BID therapy were significantly higher than those of 5 mg BID recipients. A significant and strong positive correlation was observed between AXA and PT at trough and peak times. The AXA values and PT in the DAC group were significantly higher than those in the non-DAC group. No significant inter-group differences were seen in APTT. This study provides the first report of AXA distribution in VTE patients receiving 10 mg BID of apixaban. Our findings indicate that coagulation markers may differ in patients with VTE-prescribed higher doses of apixaban and a DAC may be warranted in such patients.

Dramatically prolonged coagulation screening tests in a patient with positive lupus anticoagulant and monoclonal immunoglobulin M without bleeding manifestations

BACKGROUND

Concomitant presence of lupus anticoagulant (LA) and monoclonal immunoglobulin in the same patient is uncommon and the influence of this finding on coagulation results is still unknown.

CASE REPORT

We present a patient with a diagnosis of systemic lupus erythematosus (SLE) and secondary antiphospholipid syndrome (APS) with permanently positive LA who presented with accidental finding of newly discovered monoclonal IgM in a high concentration and dramatically prolonged prothrombin time (PT) and activated partial thromboplastin time (aPTT), without bleeding manifestations.

CONCLUSION

Concomitant presence of extremely prolonged PT and aPTT with unusual coagulation reaction kinetics, consistent LA ratio over the follow-up period and normalization of coagulation screening results with decreasing monoclonal IgM concentration elicited suspicion that PT and aPTT prolongation could be attributed to M-protein with antiphospholipid specificity. Low LA-sensitive aPTT reagent Actin FS demonstrated exceptional sensitivity, whereas human placental thromboplastin in contrast to recombinant reagents showed significantly lower sensitivity to monoclonal IgM with antiphospholipid specificity. Changes in the activity of SLE observed during the follow-up period were inversely related to monoclonal IgM concentration, while the presence of secondary APS was consistent. Described analytical interference on PT and aPTT without bleeding manifestation should point towards suspicion of previously unidentified monoclonal IgM with antiphospholipid sensitivity.

Comparison of clinical outcomes using activated partial thromboplastin time versus antifactor-Xa for monitoring therapeutic unfractionated heparin: A systematic review and meta-analysis

INTRODUCTION

Continuous intravenous unfractionated heparin (UFH) is a mainstay of therapeutic anticoagulation in the acute setting. The two most common laboratory tests for monitoring UFH are the activated partial thromboplastin time (aPTT) and antifactor Xa (anti-Xa) heparin assay. We reviewed the available evidence to evaluate if the choice of monitoring test for UFH therapy is associated with a difference in the clinical outcomes of bleeding, thrombosis, or mortality.

MATERIALS AND METHODS

MEDLINE, Cochrane database, and conference abstracts from the Society of Critical Care Medicine, the American Society of Hematology, and the American College of Clinical Pharmacy were searched for all studies comparing aPTT and anti-Xa monitoring for therapeutic UFH that evaluated outcomes for bleeding, thrombotic events, or mortality. Risk of bias was assessed with the Cochrane Risk of Bias Tool and Newcastle Ottawa Scale. Pooled relative risk ratios were calculated using an inverse variance-weighted random-effects model.

RESULTS

Ten studies (n = 6677) were included for analysis. The use of anti-Xa compared to aPTT was not associated with an increased risk of bleeding (RR 1.03; 95% CI 0.8-1.22 I² = 4%) or an increased risk of thrombotic events (RR 0.99; 95% CI 0.76-1.30, I² = 3%). There was no difference in mortality within individual studies but the data were not suitable for pooled analysis.

CONCLUSIONS

Pooled data comparing aPTT vs. anti-Xa for monitoring therapeutic UFH did not suggest differences in the outcomes of bleeding or thrombosis.

Antithrombotic property of an aqueous extract from Pseudocedrela kotschyi and Adenia cissampeloides

Background and purpose:

An aqueous extract from the root bark of Pseudocedrela kotschyi and aerial parts of Adenia cissampeloides has been proven in previous research to elicit significant anticoagulant property in vitro. This, therefore, indicates the potential usefulness of this extract in managing thromboembolic disease, a major global health risk. The aim of the present work was to establish the antithrombotic effect of a product made from extracts of the root bark of P. kotschyi and the aerial parts of A. cissampeloides (PAE).

Experimental approach:

The effect of PAE at 500-2000 mg/kg in inhibiting tail infarction and inflammation, as well as its effect on the microthrombi count, hematological, and coagulation profiles in a carrageenan-induced thrombosis model in Sprague-Dawley rats, was studied.

Findings/Results:

PAE significantly (P ≤ 0.01-0.001) reduced length of tail infarction and inflammation (redness, swelling, pain, and temperature). Histopathological studies revealed a significant reduction (P ≤ 0.0001) in microthrombi count in the liver and the lungs with PAE treatment. PAE treatment caused a marginal (P ≤ 0.01) increase in prothrombin time but resulted in a significant (P ≤ 0.01-0.0001) dose-dependent increase in activated partial thromboplastin time, with the hematological profile being normal.

Conclusion and implications:

PAE showed anticoagulant and antithrombotic effects in vivo, indicative of its potential benefit as a natural product, and cost-effective therapeutic option, and hence could be helpful in thromboembolic therapies.

The clinical significance of a shortened activated partial thromboplastin time in patients with connective tissue disease

INTRODUCTION

Connective tissue disease (CTD) patients have been reported to have an increased risk of venous thromboembolism (VTE). Deep venous thrombosis represents a potential emergency that may have a fatal outcome. The D-dimer test is the most widely accepted screening marker for VTE; however, elevation of the plasma D-dimer level without demonstrable thrombosis sometimes accompanies CTD activity itself, infection, and other conditions. Thus, the accuracy of a diagnosis of VTE based on a D-dimer test result is lower in CTD patients. The activated partial thromboplastin time (APTT) test is a very common and simple test.

METHOD

The medical records of 535 CTD patients were retrospectively investigated. The following data were extracted: APTT, D-dimer, thrombotic events, laboratory data, and systemic corticosteroid therapy.

RESULTS

The rates of thrombotic events and VTE were significantly increased in patients with a shortened APTT (< 26 s) (PSAPTT) in comparison to those without a shortened APTT (p = 0.004, 0.0009, respectively). The number of PSAPTTs was significantly increased in patients with VTE in comparison to those without VTE (p = 0.0009). In the diagnosis of VTE in CTD patients, the specificity and positive predictive value (PPV) of the D-dimer test were 71.6% and 83.8% and 12.7% and 19.4%, respectively. The combination of a shortened APTT and elevated plasma D-dimer level improved the specificity and PPV to 94.7% and 97.3% and to 25.0% and 36.4%, respectively.

CONCLUSIONS

For the evaluation of possibility of accompanying VTE in CTD patients, APTT shortened was useful and should be evaluated with careful attention.

KEY POINTS

• Regarding the specificity for diagnosing VTE in CTD patients, a shortened APTT showed a value (84.3%) comparable or superior to that of the D-dimer test. • The combination of a shortened APTT and elevated D-dimer level improved the specificity of the diagnosis of VTE in CTD patients to (94.7% or 97.3%) in comparison to the D-dimer test alone (71.6% or 83.8%). • The positive predictive value of the combination of a shortened APTT and plasma D-dimer elevation for the diagnosis of VTE in CTD patients increased to 25.0% or 36.4%. • In the management of CTD patients, physicians should pay attention when they encounter patients with a shortened APTT, as it may indicate VTE.

Relationship between admission coagulopathy and prognosis in children with traumatic brain injury: a retrospective study

BACKGROUND

Coagulopathy in adult patients with traumatic brain injury (TBI) is strongly associated with unfavorable outcomes. However, few reports focus on pediatric TBI-associated coagulopathy.

METHODS

We retrospectively identified children with Glasgow Coma Scale ≤ 13 in a tertiary pediatric hospital from April 2012 to December 2019 to evaluate the impact of admission coagulopathy on their prognosis. A classification and regression tree (CART) analysis using coagulation parameters was performed to stratify the death risk among patients. The importance of these parameters was examined by multivariate logistic regression analysis.

RESULTS

A total of 281 children with moderate to severe TBI were enrolled. A receiver operating characteristic curve showed that activated partial thromboplastin time (APTT) and fibrinogen were effective predictors of in-hospital mortality. According to the CART analysis, APTT of 39.2 s was identified as the best discriminator, while 120 mg/dL fibrinogen was the second split in the subgroup of APTT ≤ 39.2 s. Patients were stratified into three groups, in which mortality was as follows: 4.5 % (APTT ≤ 39.2 s, fibrinogen > 120 mg/dL), 20.5 % (APTT ≤ 39.2 s and fibrinogen ≤ 120 mg/dL) and 60.8 % (APTT > 39.2 s). Furthermore, length-of-stay in the ICU and duration of mechanical ventilation were significantly prolonged in patients with deteriorated APTT or fibrinogen values. Multiple logistic regression analysis showed that APTT > 39.2 s and fibrinogen ≤ 120 mg/dL was independently associated with mortality in children with moderate to severe TBI.

CONCLUSIONS

We concluded that admission APTT > 39.2 s and fibrinogen ≤ 120 mg/dL were independently associated with mortality in children with moderate to severe TBI. Early identification and intervention of abnormal APTT and fibrinogen in pediatric TBI patients may be beneficial to their prognosis.

The change of coagulation profile in two-staged arthroplasty for periprosthetic joint infection patients: a retrospective cohort study

Aims

Periprosthetic joint infection (PJI) is a serious complication of total joint arthroplasty. We performed a retrospective cohort study to evaluate (1) the change of coagulation profile in two-staged arthroplasty patients and (2) the relationship between coagulation profile and the outcomes of reimplantation.

Method

Between January 2011 and December 2018, a total of 202 PJI patients who were operated on with two-staged arthroplasty were included in this study initially. This study continued for 2 years and the corresponding medical records were scrutinized to establish the diagnosis of PJI based on the 2014 MSIS criteria. The coagulation profile was recorded at two designed points, (1) preresection and (2) preimplantation. The difference of coagulation profile between preresection and preimplantation was evaluated. Receiver operating characteristic curves (ROC) were used to evaluate the diagnostic efficiency of the coagulation profile and change of coagulation profile for predicting persistent infection before reimplantation.

Results

The levels of APTT, INR, platelet count, PT, TT, and plasma fibrinogen before spacer implantation were significantly higher than before reimplantation. No significant difference was detected in the levels of D-dimer, ACT, and AT3 between the two groups. The AUC of the combined coagulation profile and the change of combined coagulation profile for predicting persistent infection before reimplantation was 0.667 (95% CI 0.511, 0.823) and 0.667 (95% CI 0.526, 0.808), respectively.

Conclusion

The coagulation profile before preresection is different from before preimplantation in two-staged arthroplasty and the coagulation markers may play a role in predicting infection eradication before reimplantation when two-stage arthroplasty is performed.

Level of evidence

Level III, diagnostic study.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13018-021-02477-4.

Pseudo Heparin Resistance After Pulmonary Endarterectomy: Role of Thrombus Production of Factor VIII

Pulmonary endarterectomy (PEA) is the main treatment for chronic thromboembolic pulmonary hypertension (CTEPH). Postoperative unfractionated heparin dosing can be monitored by activated partial thromboplastin time (APTT) or by anti-factor Xa activity (anti-Xa). In pseudo heparin resistance, APTT response to heparin is blunted due to elevated Factor VIII (FVIII) which can underestimate anticoagulation. We examined possible pseudo heparin resistance after PEA and assessed the impact of FVIII. APTT response to heparin before and after operation was determined in 13 PEA patients anticoagulated with unfractionated heparin. APTT and anti-Xa concordance was analyzed from paired postoperative samples, and antithrombin, fibrinogen and FVIII levels were measured. Single-cell RNA sequencing was used to characterize FVIII gene expression in PEA specimens of 5 patients. APTT response to heparin was blunted after PEA. APTT and anti-Xa were discordant in 36% of postoperative samples and most common discordant patterns were subtherapeutic APTT with therapeutic (16%) or supratherapeutic (11%) anti-Xa. Overall, APTT underestimated anticoagulation relative to anti-Xa in one-third of the samples. FVIII levels were elevated before surgery, increased substantially 1 and 3 days (median 4.32 IU/mL) after PEA, and were higher in discordant than concordant samples. Single-cell RNA sequencing showed FVIII gene expression in PEA specimen endothelial cells. Pseudo heparin resistance is common after PEA likely due to highly elevated postoperative FVIII levels indicating that anti-Xa reflects postoperative heparinization better than APTT in these patients. FVIII production by the pulmonary artery endothelium may participate in local prothrombotic processes important for CTEPH pathogenesis.

von Willebrand factor activity and activated partial thromboplastin time as proxy biomarkers for coagulopathies in women with menorrhagia in Zambia: a case-control study

Introduction

von Willebrand Disease (vWD) is the most prevalent bleeding disorder. Women are more likely to manifest abnormal bleeding symptoms due to physiologic events and menorrhagia is the most common presenting symptom.

Methods

this case-control study included 168 women aged between 18 and 45. The cases had menorrhagia whilst the controls did not. Blood grouping, activated partial thromboplastin time and von Willebrand factor activity tests were performed on samples collected from consenting study participants.

Results

the mean age was 29.96 ± 7.37. Mean vWF activity of cases was 66.6% and of controls 97.8%. The mean activated Partial ThromboplastinTime (aPTT) of cases was 31.09s and of controls was 30.40s. There was no difference in the vWF activity between blood group O (86.3%) and non-blood group O (88.0%) participants. Eight women were diagnosed with von Willebrand disease, 6 cases and 2 controls. Higher odds of von Willebrand disease were seen in the cases (OR = 6.6). Epistaxis, von Willebrand and factor activity levels and family history of menorrhagia were associated with an increased risk for menorrhagia.

Conclusion

von Willebrand factor activity levels were associated with menorrhagia while activated partial thromboplastin time was not. vWF activity levels did not depend on any specific blood group. The prevalence of von Willebrand disease was significantly higher in participants with menorrhagia and repeated epistaxis and family history of menorrhagia pointed to a higher risk of menorrhagia.

Evaluation of the merit of the methanolic extract of Andrographis paniculata to supplement anti-snake venom in reversing secondary hemostatic abnormalities induced by Naja naja venom

Increasing evidence suggests a sizable involvement of hemotoxins in the morbidity associated with envenomation by the Indian spectacled cobra, Naja naja (N.N). This study investigates the ability of Indian polyvalent anti-snake venom (ASV), methanolic extract of Andrographis paniculata (MAP) and their combination in reversing the hemostatic abnormalities, viz. activated partial thromboplastin time(aPTT), prothrombin time(PT) and thrombin time(TT) in citrated plasma. These parameters were assessed in 2 groups of experiments. Group 1: Without the prior incubation of plasma with venom and Group 2: With prior incubation of plasma with venom for 90 min at 37°C. Venom caused significant (p < 0.001) prolongation in aPTT (175%), PT (49%) and TT (34%) in Group 1 and ASV could completely bring them back to normal. MAP showed a concentration-dependent reversal in aPTT, normalization of PT and prolongation of TT. When low concentration of ASV was supplemented with MAP, their combined effect in normalizing aPTT and PT improved by 37% and 26% respectively when compared to ASV alone. In Group 2, venom caused significant (p < 0.001) prolongation in aPTT (231%), PT (312%) and TT (245%). ASV had limited effect in reversing aPTT (52%), TT (31%) but completely normalized PT. MAP was marginally effective in reversing the prolonged aPTT and PT but caused further prolongation of TT. Combination of ASV and MAP was more effective than ASV alone in reversing venom-induced increase in aPTT (52%) and PT (29%). The study proved that, a drastic reduction of ASV by 70%, could be effectively supplemented by MAP in combating hemostatic abnormalities induced by NN venom.

Impact of inflammatory cell ratio, biomarkers, activated partial thromboplastin time and prothrombin time on chronic subdural haematoma severity and outcome

INTRODUCTION

Chronic subdural haematoma (CSH) has multifactorial mechanisms involved in its development and progression. Identifying readily available inflammatory and coagulation indices that can predict the prognosis of CSH will help in clinical care, prognosis, generating objective criteria for assessing efficacy of treatment strategies and comparisons of treatment efficacy between clinical studies. We conducted a study in which we evaluated the impact value of neutrophil to lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), inflammatory biomarkers (erythrocyte sedimentation rate and C-reactive protein), activated partial thromboplastin time (APTT), prothrombin time (PT) and international normalized ratio (INR) at presentation on CSH severity and outcome using Glasgow outcome scale (GOS), Markwalder grading scale (MGS) and Lagos brain disability examination scale (LABDES).

METHODS

We prospectively studied patients in a single healthcare system with clinical and radiological features of chronic subdural haematoma. Only patients who were managed surgically were recruited. The primary outcome was predictors of severe form CSH (using admission Glasgow coma scale score, MGS grade, inflammatory cells and biomarkers, APTT, PT, and INR) and outcome (using GOS, MGS and LABDES grades 3 months) with secondary outcome being mortality rate, 3 months following surgery. Good outcome was defined as GOS score > 3, LABDES score ≥ 40 at three months and MGS score < 2. Differences in categorical and continuous variables between groups were compared using Fisher's exact test or Chi-square test (χ2) analysis, one-way ANOVA or Kruskal-Wallis test (in case of non-normal distribution).

RESULTS

We included 61 patients with a male-to-female ratio of 2.6:1 and mean age of 57.5 ± 13.3 years (median 58 years; 27-83 years). The pre-op MGS grade was significantly associated with the LABDES (p = 0.034), GOS (p = 0.011) and post-op MGS (p = 0.007) grade. All the patients that died had elevated APTT and PT with low PLR. A low admission PLR was significantly associated with a poor outcome using the GOS (p = 0.001), MGS (p = 0.011) and LABDES grade (p = 0.006) (Table 3). A high APTT was also significantly associated with a worse outcome using GOS (p = 0.007), MGS (p = 0.007) and LABDES grade (p = 0.003). There were three (4.9%) deaths with post-mortem diagnosis of pulmonary embolism, chronic renal failure and irreversible craniocaudal herniation syndrome. All the patients that died had elevated APTT and PT with low PLR.

CONCLUSION

Patients' admission APTT, PT, INR and PLR are good predictors of outcome using the GOS. A high admission INR is also associated with a worse outcome using MGS and LABDES grade.

Comparative analysis of chromogenic vs clot.based one stage APTT assay for determination of factor VIII level

Background

In the laboratory, factor VIII can be measured by three different methodologies, such as one-stage clotting assay, two-stage clotting assay, and chromogenic assay. These assays differ in ease of use, variety of reagents available, sensitivity to mild hemophilia A, and interference from lupus anticoagulants (LACs). Certain factor VIII gene mutations can cause discrepancy in results between one-stage activated partial thromboplastin time (APTT) and chromogenic assays.

Materials and Methods

The coagulometer for factor VIII assay is Sysmex CS-5100. All data were expressed as mean ± standard deviation (SD).

Results

A total of 135 cases were studied. Of these, 100 cases were of mild hemophilia A diagnosed by molecular genetics and, 15 cases were positive for LAC, which were confirmed by dilute Russell Viper venom test. Clot-based one-stage APTT assay showed 65% sensitivity and 80% specificity in diagnosing mild hemophilia A cases and out of 15 LAC cases, it showed false positivity in five cases. Chromogenic assay showed 85% sensitivity and 90% specificity in diagnosing mild hemophilia cases and was 100% specific in excluding LAC cases.

Conclusions

One-stage APTT assay is the most commonly used test for determining factor VIII levels but chromogenic assay are considered as the gold standard and recommended as the reference method by European Pharmacopoeia and ISTH subcommittee. Mild hemophilia A patients with missense mutations show discrepancy between the one-stage clot-based APTT assay and chromogenic assays for determination of factor VIII level and this can lead to misdiagnosis or misclassification of mild hemophilia A. Therefore, it is recommended that both the assays should be used in the evaluation of mild hemophilia cases.

A nomogram to early predict isolation length for non-severe COVID-19 patients based on laboratory investigation: A multicenter retrospective study in Zhejiang Province, China

BACKGROUND

Majority coronavirus disease 2019 (COVID-19) patients are classified as mild and moderate (non-severe) diseases. We aim to develop a model to predict isolation length for non-severe patients.

METHODS

Among 188 non-severe patients, 96 patients were enrolled as training cohort to identify factors associated with isolation length via Cox regression model and develop a nomogram. Other 92 patients formed as validation cohort to validate nomogram. Concordance index (C-index), area under the curve (AUC) and calibration curves were used to evaluated nomogram.

RESULTS

Increasing absolute eosinophil count (AEC) after admission was correlated with shorter isolation length (P = 0.02). Baseline activated partial thromboplastin time (APTT) > 30 s was correlated with longer isolation length (P = 0.03). A nomogram to predict isolation probability at 11-, 16- and 21-day was developed and validated. The C-indices of training and validation cohort were 0.604 and 0.682 respectively. Both cohorts showed a good discriminative ability (AUC, 11-day: 0.646 vs 0.730; 16-day: 0.663 vs 0.750; 21-day: 0.711 vs 0.783; respectively) and calibration power.

CONCLUSIONS

Baseline APTT and dynamic change of AEC were two significant factors associated with isolation length of non-severe patients. Nomogram could predict isolation probability for each patient to estimate appropriate quarantine length.

Left atrial thrombus formation within a few days of hospitalization in semi-acute ischemic heart disease despite no atrial fibrillation and mitral stenosis: a case report

BACKGROUND

Currently, the occurrence of left atrial thrombus despite the provision of heparinization within a few days of hospitalization without atrial fibrillation (AF) and mitral stenosis (MS) is rarely reported.

CASE PRESENTATION

A 71-year-old woman presented with chest discomfort and dyspnea. Examination revealed ST elevation with sinus rhythm, congestive heart failure, and moderate mitral regurgitation (MR) by transthoracic echocardiography (TTE). Diuretics, a coronary vasodilator, and unfractionated heparin (15,000 units/day) were administered. Four days after hospitalization, her C-reactive protein level had increased; therefore, TTE was repeated, revealing a thrombus in the left atrial appendage, which was probably affected by heparin resistance because of low antithrombin (49%). On day 5, the patient underwent emergency removal of the thrombus, mitral valve replacement, and coronary artery bypass.

CONCLUSION

Patients can exhibit low left ventricular contractility, even sinus rhythm without MS. Thus, TTE and subsequent coagulation tests including antithrombin must be performed to prevent thrombus.

Prolonged activated partial thromboplastin time after prophylactic-dose unfractionated heparin in the post-operative neurosurgical setting: case series and management recommendations

Primary brain tumors, both benign and malignant, pose a high risk of perioperative venous thromboembolism (VTE) due to the development of a prothrombotic state. Perioperative pharmacologic thromboprophylaxis with subcutaneous (SC) unfractionated heparin (UFH) has significantly reduced VTE associated morbidity. Recent reports suggest an association between prolonged activated partial thromboplastin time (aPTT) due to prophylactic SC UFH and increased bleeding risk. We present three patients with normal baseline coagulation parameters in whom pharmacologic thromboprophylaxis with SC UFH resulted in a marked prolongation of the aPTT, leading to adverse outcomes in two patients. These cases demonstrate the uncertain kinetics of SC UFH and effect on aPTT, suggesting the significance of routine aPTT monitoring in high-risk settings. Given the wide variation in presentations of therapeutic or supratherapeutic values of aPTT in the perioperative neurosurgical setting, we propose a practical standardized approach to the evaluation and management of aPTT prolongation following prophylactic SC UFH administration.

Oxidized LDL induces procoagulant profiles by increasing lysophosphatidylcholine levels, lysophosphatidylethanolamine levels, and Lp-PLA2 activity in borderline hypercholesterolemia

BACKGROUND AND AIMS

The increased risk of cardiovascular disease under hypercholesterolemia is due to associations between oxidized low-density lipoprotein (ox-LDL) and lipoprotein-associated phospholipase A₂ (Lp-PLA₂) and between ox-LDL and coagulant profiles. We investigated the impact of different ox-LDL levels on coagulation time and plasma metabolomes in subjects with borderline hypercholesterolemia.

METHODS AND RESULTS

One hundred thirty-one subjects with borderline hypercholesterolemia (serum cholesterol ≥200 mg/dL) were divided into low ox-LDL (n = 66) and high ox-LDL (n = 65) groups. After adjusting for confounding factors, the high ox-LDL group exhibited a significantly decreased activated partial thromboplastin time (aPTT) and prothrombin time (PT) and increased Lp-PLA₂ activity. Compared to the low ox-LDL group, the high ox-LDL group exhibited significantly increased intensities of 17 lysophosphatidylcholines (lysoPCs) and 7 lysophosphatidylethanolamines (lysoPEs). Ox-LDL was inversely correlated with aPTT and PT and positively correlated with Lp-PLA₂ activity. Positive correlations were also found among ox-LDL, Lp-PLA₂ activity, lysoPCs, and lysoPEs. LysoPCs and lysoPEs were inversely correlated with PT and aPTT. The identified plasma metabolites, including amino acids, fatty acid amides, acylcarnitines, and lysophospholipids, were significantly upregulated in the high ox-LDL group.

CONCLUSION

High ox-LDL levels may be involved in the development of a procoagulant state in subjects with borderline hypercholesterolemia by increasing Lp-PLA₂ activity and lysoPC and lysoPE levels.

The prognostic value of routine coagulation tests for patients with heat stroke

OBJECTIVE

To evaluate the prognostic value of routine coagulation tests for patients with heat stroke.

METHODS

This was a multi-center retrospective study. Patients who arrived at the hospital <24 h after the onset of Heat Stroke (HS) were included. The routine coagulation variables were detected within 24 h after the onset, including the lowest platelet count (PLC).

RESULTS

60-day mortality rate was 20.9%. The median Prothrombin Time-International Normalized Ratio (PT-INR) of the non-surviving patients was significantly higher than that of the survivors (P < 0.01). The median Activated Partial Thromboplastin Time (APTT) in non-surviving patients was significantly higher than in the surviving patients (P < 0.01). A Cox regression analysis revealed that 60-day mortality was associated with PT-INR (P = 0.032) and APTT (P = 0.004). The optimal PT-INR point for predicting 60-day mortality rate was 1.7. The optimal APTT point for predicting 60-day mortality was 51.45. Patients with increased PT-INR (≥1.7) levels had, overall, a significantly reduced survival time (P < 0.01). Patients with elevated APTT (≥51.45) also had a decrease in survival time (P < 0.01). The prognostic scoring, with increased PT-INR (≥1.7) and prolonged APTT (≥51.45) at one point each, was also demonstrated to be useful in predicting 60-day mortality. Patients whose temperature fell to 38.9 °C within 30 min had significantly lower levels of PT-INR and APTT within 24 h than those who took longer to cool down.

CONCLUSIONS

A prolonged APTT and elevated PT-INR within 24 h are independent prognostic factors of 60-day mortality in HS.

Influence of saliva on the results of global laboratory coagulation tests

BACKGROUND

Oral wounds inevitably come into contact with saliva which can affect the time needed for bleeding to stop. The influence of saliva can be non-specific, related to dilution of blood, and/or mediated by salivary factors that affect haemostasis directly. The aim of this study was to assess if mixing blood with an individual's saliva would affect the rate of its coagulation measured by global coagulation tests, prothrombin time (PT) and activated partial thromboplastin time (APTT).

METHODS

The study included 30 healthy non-smoking volunteers. Paired blood and unstimulated saliva samples were obtained from each participant and PT and APTT were determined in blood, blood + saliva and blood + water mixtures. Coagulation tests were performed using the mechanical clot detection method.

RESULTS

PT was significantly longer in both blood + saliva and blood + water mixtures compared to blood alone. APTT was significantly longer only in blood + water mixture compared to blood.

CONCLUSIONS

Similarly prolonged PT in both mixtures suggests that both saliva and water prolong coagulation evenly due to their non-specific effect of blood dilution. The finding that APTT was significantly prolonged only when blood was mixed with water could indicate presence of tissue factor in saliva, however, in a concentration too low to influence the results of PT.

Orally bioavailable amine-linked macrocyclic inhibitors of factor XIa

The discovery of orally bioavailable FXIa inhibitors has been a challenge. Herein, we describe our efforts to address this challenge by optimization of our imidazole-based macrocyclic series. Our optimization strategy focused on modifications to the P2 prime, macrocyclic amide linker, and the imidazole scaffold. Replacing the amide of the macrocyclic linker with amide isosteres led to the discovery of substituted amine linkers which not only maintained FXIa binding affinity but also improved oral exposure in rats. Combining the optimized macrocyclic amine linker with a pyridine scaffold afforded compounds 23 and 24 that were orally bioavailable, single-digit nanomolar FXIa inhibitors with excellent selectivity against relevant blood coagulation enzymes.

Effect of emicizumab on global coagulation assays for plasma supplemented with apixaban or argatroban

Emicizumab is a bi-specific humanized monoclonal antibody mimicking the factor (F) VIII cofactor activity in mediating the activation of FX by FIXa. Recent observations showed that emicizumab when added to pooled normal plasma (PNP), hemophilic plasma or PNP added with unfractionated heparin is able to interfere with coagulation assays. To further explore the mechanisms of assay interference we investigated the effect of emicizumab on global coagulation assays for the PNP added with two direct oral anticoagulants, apixaban or argatroban. Aliquots of PNP were added with purified apixaban or argatroban at a concentration of 500 ng/mL and emicizumab at concentrations ranging from 0 to 100 µg/mL. Plasma samples were then tested for the activated partial thromboplastin time (APTT) and for thrombin generation (the latter for the apixaban plasma only). Emicizumab at a 25-50 µg/mL shortened the APTT of the PNP with or without apixaban or argatroban. The extent of correction was greater for the apixaban or argatroban plasma and amounted to 35% or 42%, respectively. The parameters of thrombin generation (lag-time and time-to-peak) for the PNP supplemented with apixaban were shortened by 30% or 25%, respectively and the endogenous thrombin potential and the peak-thrombin were marginally affected. Emicizumab attenuates in vitro the anticoagulant activity of the PNP induced by apixaban or argatroban as documented by the correction of prolonged APTT and velocity of thrombin generation (i.e., lag-time and time-to-peak). Whether the above effects have any relevance in vivo is unknown.

Clinicoepidemiologic Features of Chronic Spontaneous Urticaria in Patients with Elevated Plasma D-Dimer Levels versus those without It: A Case-Control Cross-Sectional Study of 100 Indian Patients

Background

Activated coagulation cascade is implicated in urticaria pathogenesis marked by high plasma D-dimer, a marker of fibrinolysis, levels correlating with high urticaria activity score (UAS) and poor therapeutic outcome.

Methods

Quantitative plasma D-dimer levels and coagulation parameters in 100 (male:female ratio 1:3) Indian patients with chronic spontaneous urticaria and age- and gender-matched healthy controls were compared. The clinicoepidemiologic features of chronic urticaria were then compared among patients with normal (≤0.2 mg/L) and elevated (≥0.3 mg/L) plasma D-dimer levels.

Results

Plasma D-dimer in 23% patients and 4% controls and prothrombin time and activated partial thromboplastin time in 63% and 5% patients, respectively, were significantly higher compared with 58% and 1% of controls, respectively. About 18 of 72 (25%) patients with high UAS of ≥16-42 were compared with 5 of 28 (17.8%) patients with UAS7 of ≤15. Patients with elevated plasma D-dimer levels had significantly more systemic symptoms (86.9% vs. 81.8%) compared with patients with normal plasma D-dimer levels.

Conclusion

A subset of patients with chronic urticaria have elevated plasma D-dimer levels and exhibit higher UAS7 and systemic symptoms that may influence long-term prognosis and therapeutic choices. Small number of patients, a cross-sectional nature of study, lack of treatment outcome measures, information on self-medication, and unavailability of specific parameters for coagulation pathway activation remain few limitations of this study.

Structure based design of macrocyclic factor XIa inhibitors: Discovery of cyclic P1 linker moieties with improved oral bioavailability

This manuscript describes the discovery of a series of macrocyclic inhibitors of FXIa with oral bioavailability. Assisted by structure based drug design and ligand bound X-ray crystal structures, the group linking the P1 moiety to the macrocyclic core was modified with the goal of reducing H-bond donors to improve pharmacokinetic performance versus 9. This effort resulted in the discovery of several cyclic P1 linkers, exemplified by 10, that are constrained mimics of the bioactive conformation displayed by the acrylamide linker of 9. These cyclic P1 linkers demonstrated enhanced bioavailability and improved potency.

Investigation of the Safety of Injection Laryngoplasty under Antithrombotic Therapy

BACKGROUND

Glottic insufficiency negatively affects phonation and swallowing function. Injection laryngoplasty is a convenient and minimally invasive treatment for glottic insufficiency. This study assessed whether injection laryngoplasty is safe under continued administration of antithrombotic drugs, and aimed to establish measurable laboratory values under which such a procedure can be safely performed.

METHOD

This retrospective medical record review covered the period from November 2012 to June 2018. We examined 17 patients who underwent injection laryngoplasty (47 injections) under continued administration of antithrombotic drugs at the University of Tokyo Hospital. We analyzed clinical and demographic profiles, complications, and blood test values. Statistical analyses were performed regarding the risks of complications due to injection side, route of administration, and number of antithrombotic drugs.

RESULTS

No patients exhibited airway narrowing or dyspnea; however, bleeding after injection laryngoplasty was observed in 3 patients. All patients exhibited values within the optimal treatment range. There were no significant differences regarding the risks of complications due to injection side, route of administration, or number of antithrombotic drugs.

CONCLUSIONS

When the platelet count, prothrombin time-international normalized ratio, and activated partial thromboplastin time were within the optimal range prior to treatment, injection laryngoplasty could safely be performed, regardless of the administration of antithrombotic drugs.

Prothrombin time, activated partial thromboplastin time and platelet counts of type II diabetes mellitus: a comparative study

Background

The incidence of cardiovascular disease due to thrombosis is 2-4 folds greater in diabetic patients. Prothrombin time, activated partial thromboplastin time and platelet count are hematological indices that give an insight into the coagulation status. Hence, this study aims to assess the coagulation status of type II diabetic patients.

Methods

A comparative cross-sectional study was conducted at Bahir Dar Felege Hiwot referral hospital, Northwest Ethiopia. A total of 40 treated type II diabetic, 40 untreated diabetics and 40 non-diabetic subjects were included. After taking informed consent, structured questionnaire was used to collect socio-demographic data. Following interview, 4 ml of blood was collected to determine PT, aPTT and platelet count of the three groups. The data were entered into SPSS version 20 and analyzed. One-way ANOVA was used to compare means of PT, aPTT and platelet count among the groups. A P value less than 0.05 was considered as statistically significant.

Results

The mean aPTT of non-diabetic, treated and untreated type II diabetic patient was 32.8 ± 4.12 s, 34.4 ± 5.3 s, and 25.42 ± 8.46 s, respectively. The proportion of untreated diabetic patients with normal PT, aPTT and platelet counts was 60.0%, 7.5 and 92.5%, respectively. There was a significant shortening of aPTT in untreated diabetic as compared to both treated and non-diabetic controls (P < 0.001).

Conclusions

Shortening of aPTT in untreated type II diabetic patients might be useful marker in patients with diabetes. Therefore, monitoring the aPTT in newly diagnosed diabetic patients is important.

Agreement between activated partial thromboplastin time and anti-Xa activity in critically ill patients receiving therapeutic unfractionated heparin

BACKGROUND

No study supports the use of either aPTT or anti-Xa activity for heparin monitoring in critical care patients. There are no strong data on the agreement between aPTT and anti-Xa. The aims of this study were to: 1. Analyse the agreement between aPTT and anti-Xa in a large population of critically ill patients under unfractionated heparin therapy (UFH), 2. Identify clinical and biological factors associated to agreement or disagreement, and 3. Analyse the impact of anti-Xa availability on the use of aPTT and UFH therapy.

METHODS

Retrospective study in a 35 beds mixed-ICU population between 2006 and 2016 in a University teaching hospital.

INCLUSION CRITERIA

delivery of a UFH dose >15,000 U/24 h during at least one day with one anti-Xa determination.

DATA

demographic variables, aPTT, anti-Xa, laboratory variables, presence of extracorporeal devices (ECD). Pairs of simultaneously dosed aPTT and anti-Xa [aPTT:anti-Xa] were analysed on the basis of their agreement within the sub-therapeutic, therapeutic (aPTT 50-80″, anti-Xa 0.3-0.7 U/ml) or supra-therapeutic ranges.

RESULTS

2283 patient admissions (2085 patients) were analysed. 35,595 [aPTT:anti-Xa] pairs were found. The overall [aPTT:anti-Xa] agreement was 59.6% and lowest (54.3%) in presence of ECD compared to non-ECD patients (61.6%; p < 0.001). Sixteen demographic and biological variables were analysed and were not predictive of [aPTT:anti-Xa] agreement. No significant difference in administered UFH dose was observed after anti-Xa introduction.

CONCLUSION

In this large cohort, the [aPTT:anti-Xa] agreement is <60% and significantly lower in patients with ECD. None of the variables identified as potentially affecting the agreement were predictive. Availability of anti-Xa had neither effect on aPTT use nor on UFH-dose. These results call for a prospective study to determine the optimal UFH-therapy monitoring tool.

Evolution of haemostatic parameters and risk of bleeding during treatment with cefazolin

In 2017, five cases of severe haemorrhages during treatment with cefazolin occurred in France. The aim of this study was to assess the risk of haemorrhage related to treatment with cefazolin by evaluating haemostatic parameters and bleeding events. A retrospective study was conducted from January 2016 to December 2017. Two populations were analysed: (i) overall population, which included all patients treated with cefazolin during this period and (ii) coagulation study population, which included all patients treated with cefazolin with available coagulation parameters (activated partial thromboplastin time (aPTT) and international normalised ratio (INR) at baseline and at the end of treatment or EoT). Values of either aPTT or INR at baseline and at EoT were compared. Cases of severe haemorrhages were reported and correlated with values of aPTT and INR. Overall, 132 patients received cefazolin and 59/132 (45%) were included in the coagulation study group. A significant increase of median aPTT was observed from baseline to EoT (39.5 and 44.3 sec; p = 0.004, respectively). Overall, severe haemorrhage occurred in 7/132 (5%) patients. Coagulation parameters were available in three of them, and no correlation was observed between bleeding events and aPTT increase. This study showed that bleeding is probably more frequent than ever reported before during cefazolin treatment. The significant increase of aPTT observed during cefazolin treatment was not correlated with risk of haemorrhage. Further studies are needed to explore the possible physio-pathological pathways behind the modification of haemostatic parameters and risk of haemorrhage.

Acquired Hemophilia A: Experience of a Tertiary Care Institute from North India

Acquired hemophilia A (AHA) is an uncommon bleeding disorder infrequently reported among Indians. The present retrospective data comprises eight cases of AHA over a period of 15 years. The mean age of patients was 59.7 years. The activated partial thromboplastin time was prolonged in all cases and the inhibitor screen showed the presence of inhibitors. Factor VIII: C assay was performed in 7 cases and all cases demonstrated low levels. Lupus anticoagulant was negative. Six patients were managed with steroids and symptomatic supportive care. These patients were followed up for a mean period of 3.5 years (range 1-5 years). Of these, there was one fatality prior to initiation of therapy and one patient continues to have inhibitors.

Rare and unusual case of anti-factor XI antibodies in patient with plasma cell leukemia

Background

The acquired inhibitors of coagulation have been observed in very rare cases of monoclonal gammopathies. We report a very rare case of anti-factor XI antibodies in patient with plasma cell leukemia (PCL).

Case presentation

This is a 59-year-old male patient without pathological history, admitted to the nephrology department for management of renal insufficiency and anemia syndrome. The history and physical examination revealed stigmata of hemorrhagic syndrome including hemothorax and hemoptysis. The hemostasis assessment showed an isolated prolonged activated partial thromboplastin time (APTT) with APTT ratio = 2.0.The index of circulating anticoagulant (37.2%) revealed the presence of circulating anticoagulants. The normalized dilute Russell viper venom time ratio of 0.99 has highlighted the absence of lupus anticoagulants. The coagulation factors assay objectified the decrease of the factor XI activity corrected by the addition of the control plasma confirming the presence of anti-factor XI autoantibodies. In addition, the blood count showed bicytopenia with non-regenerative normocytic normochromic anemia and thrombocytopenia. The blood smear demonstrated a plasma cell count of 49% (2842/mm3) evoking PCL. The bone marrow was invaded up to 90% by dystrophic plasma cells. The biochemical assessment suggested downstream renal and electrolyte disturbances from exuberant light chain production with abnormalities including hyperuricemia, hypercalcemia, elevated lactate dehydrogenase, non nephrotic-range proteinuria and high level of C reactive protein. The serum protein electrophoresis showed the presence of a monoclonal peak. The serum immunofixation test detects the presence of monoclonal free lambda light chains. He was treated with velcade, thalidomide and dexamethasone. The patient died after 2 weeks despite treatment.

Conclusion

Both PCL and anti-factor XI inhibitors are two very rare entities. To the best of our knowledge, this is the first reported case of a factor XI inhibitor arising in the setting of PCL. Factor inhibitors should be suspected in patients whose monoclonal gammopathies are accompanied by bleeding manifestations.

Effect of Centrifuge Temperature on Routine Coagulation Tests

BACKGROUND

This study investigated the effects of cooled and standard centrifuges on the results of coagulation tests to examine the effects of centrifugation temperature.

METHODS

Equal-volume blood samples from each patient were collected at the same time intervals and subjected to standard (25°C) and cooled centrifugation (2-4°C). Subsequently, the prothrombin time (PT), international normalized ratio (INR), activated partial thromboplastin time (aPTT), fibrinogen, and D-dimer values were determined in runs with the same lot numbers in the same coagulation device using the Dia-PT R (PT and INR), Dia-PTT-liquid (aPTT), Dia-FIB (fibrinogen), and Dia-D-dimer kits, respectively.

RESULTS

The study enrolled 771 participants. The PT was significantly (p < 0.018) higher in participants on anticoagulant therapy. The respective median values of the test parameters determined using the standard and cooled centrifuges were as follows: PT 10.30 versus 10.50 s; PT (INR) 1.04 versus 1.09 s; APTT 28.90 versus 29.40 s; fibrinogen 321.5 versus 322.1 mg/dL; and D-dimer 179.5 versus 168.7 µg FEU/mL. There were significant differences (p < 0.001) in the parameters between the values obtained with the standard and cooled centrifuges.

CONCLUSIONS

Centrifuge temperature can have a significant effect on the results of coagulation tests. However, broad and specific disease-based studies are needed.

Association between Activated Partial Thromboplastin Time and the Amount of Infused Heparin at Bone Marrow Transplantation

The actual heparin concentration of harvested allogeneic bone marrow varies among harvest centers. We monitor the activated partial thromboplastin time (APTT) of the patient during bone marrow infusion and administer prophylactic protamine according to the APTT. We retrospectively reviewed the charts of consecutive patients who underwent bone marrow transplantation without bone marrow processing at our center between April 2007 and March 2016 (n = 94). APTT was monitored during marrow transfusion in 52 patients. We analyzed the relationship between the APTT ratio and several parameters related to heparin administration. As a result, the weight-based heparin administration rate (U/kg/hour) seemed to be more closely related to the APTT ratio (r = .38, P = .005) than to the total amount of heparin. There was no significant correlation between the APTT ratio and renal or liver function. Bleeding complications during and early after infusion were seen in 3 of 52 patients, and included intracranial, nasal, and punctured-skin bleeding. The APTT ratio during transfusion was over 5.88 in the former 2 patients and 2.14 in the latter. All of these patients recovered without sequelae. In conclusion, slow bone marrow infusion is recommended to decrease the weight-based heparin administration rate when the heparin concentration per patient body weight is high.

A case report on the successful perioperative management of hepatectomy for hepatocellular carcinoma in a patient with von Willebrand disease

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Although von Willebrand disease (VWD) is a common inherited bleeding disease, only 1 case of hepatectomy in a patient with VWD has been described.

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Perioperative hemostatic management is important especially in patients with VWD undergoing surgery because of the dysfunction of the platelet and destabilization of the blood clotting factor VIII.

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The patient was successfully treated by administering factor VIII/von Willebrand factor concentrate and by measuring activated partial thromboplastin time as an index for perioperative hemostatic management.

Introduction

Although von Willebrand disease (VWD) is a common inherited bleeding disorder, very few cases of surgery in patients with VWD have been reported.

Presentation of case

A 77-year-old man was referred to our hospital for treatment of hepatocellular carcinoma (HCC) based on type C chronic hepatitis. He had also been treated for VWD in the hematology department of another hospital. Partial hepatectomy was performed with the administration of factor VIII/von Willebrand factor concentrate just before and after the operation. The perioperative course was uneventful, and the patient was discharged 12 days after surgery.

Discussion

VWD causes dysfunction of the platelet and destabilization of the blood clotting factor VIII. The patient was successfully treated with measurement of activated partial thromboplastin time (APTT) as an index for the management of hemostasis.

Conclusion

This report describes a rare case of a successful perioperative management of hepatectomy in a patient with VWD.