Search Results (52)

Background: Acquired hemophilia A (AHA) is a bleeding disorder caused by autoantibodies against coagulation factor VIII. Treatment includes controlling bleeding and eliminating the inhibitor. Emicizumab has been increasingly used to prevent bleeding in patients with AHA. Rituximab is used as a first-line immunosuppressive therapy (IST) for AHA, either in combination with corticosteroids in high-risk patients or as monotherapy in low-risk patients who cannot tolerate corticosteroids. However, evidence regarding concomitant emicizumab and rituximab as first-line treatment for AHA is limited. Case presentations: We present five cases of AHA diagnosed at a single institution. The first three high-risk AHA cases in the era before emicizumab resulted in poor outcomes due to bleeding (Cases 1 and 3) or infection (Case 2). The recent cases (Cases 4 and 5) were successfully treated with emicizumab and rituximab-containing IST without severe bleeding and infections. Since emicizumab effectively relieved pain in these patients, rehabilitation could be initiated promptly, resulting in earlier hospital discharge. Complete remission was achieved on Day 42 in Case 4 and on Day 22 in Case 5, respectively, and emicizumab was subsequently discontinued in both cases. Conclusions: Our case series suggests that early initiation of emicizumab for patients with AHA is effective in preventing severe bleeding and subsequent immobility, and it can be combined with rituximab-containing IST to achieve remission, potentially with fewer adverse effects than standard IST. Further studies are warranted to establish the optimal treatment protocol involving emicizumab and IST for AHA. Full article

Objectives: We compared patient-reported outcomes (PROs) in persons with hemophilia A (PwHA) by inhibitor status and prescribed treatment products. Methods: Hematology Utilization Group VIII study enrolled PwHA aged ≥ 2 years to collect PRO data via surveys. A clinical chart review documented the hemophilic severity, inhibitor level and treatment regimen. PROs were compared across inhibitor status and prescribed treatment products. Results: Among 85 enrolled PwHA, 9 (10.6%) had active inhibitors, 22 (25.9%) had tolerized inhibitors, and 54 (63.5%) had no inhibitors. The no-inhibitor group was significantly older (mean: 29.3 ± 13.5 years) than the tolerized (16.3 ± 9.5 years) and active inhibitor (21.9 ± 19.1 years; p = 0.001) groups. A larger proportion of participants with active inhibitors (66.7%) and no inhibitors (53.7%) reported having bleeds in the previous month compared to those with tolerized inhibitors (22.7%, p = 0.02). After covariate adjustment for age and hemophilia severity, the tolerized inhibitor group showed the lowest estimated number of joint bleeds compared to those of the no inhibitor and active inhibitor groups (p = 0.08), and the highest EQ-5D index score (p = 0.09). Emicizumab users reported significantly fewer bleeds in the previous months than those who were prescribed standard or extended half-life factor VIII (33.3% vs. 58.6%, 64.3%, p = 0.04). Conclusions: Participants with active inhibitors experienced joint bleeding rates similar to those of participants without inhibitors, likely attributable to emicizumab use. Tolerized participants reported the fewest joint bleeds and highest quality-of-life scores, potentially reflecting younger age and possible greater prophylaxis adherence. Emicizumab was associated with lower bleed rates compared to standard or extended half-life factor VIII products. Full article

Background/Objectives: Autoimmune factor VIII deficiency (AiFVIIID) is a rare disorder that causes severe bleeding. Emicizumab has recently been found to be effective in treating AiFVIIID; however, monitoring with standard coagulation tests presents challenges. Methods: Clot waveform analysis (CWA), which involves CWA-activated partial thromboplastin time (APTT), the CWA-small amount of tissue factor activation assay (sTF/FIXa), and clotting time using a small amount of thrombin (sTT), was used to both diagnose AiFVIIID and monitor emicizumab. Results: CWA-sTT reflects the residual FVIII activity in patients with AiFVIIID. Several tests were employed, including APTT, FVIII activity, CWA, mixing tests with normal plasma, FVIII inhibitor assays, and anti-FVIII antibody activity for the diagnosis of AiFVIID in three cases. However, the sensitivity of APTT reagents to AiFVIID differed between thrombocheck-APTT and APTT-SP. Emicizumab treatment was effective for major bleeding, and anti-FVIII antibody activity could be measured using CWA-sTT. Conclusions: The sensitivity of APTT reagents to AiFVIID varies. CWA-sTT may provide utility in the diagnosis of AiFVIIID. Emicizumab is useful for the treatment of AiFVIID, and anti-FVIII antibody activity can be measured even in patients treated with emicizumab. Full article

Background: Acquired haemophilia A (AHA) is a rare autoimmune disorder characterized by the development of autoantibodies against Factor VIII activity, leading to a significant reduction in its functionality. Clinically, AHA presents with an unexpected prolongation of activated partial thromboplastin time (aPTT) and spontaneous bleeding episodes in patients without any personal or family history of haemorrhages. Bleeding manifestations can be severe at presentation, making early diagnosis and prompt treatment essential to reduce morbidity and mortality. Methods: We report on a single-centre cohort of 35 patients with AHA (examined from 1984 to 2024), analysing their demographics, underlying conditions, bleeding characteristics, treatment and outcome. Results: The median age of patients at diagnosis was 69 years (ranging from 18 to 92), 15 were males and 20 females. AHA was idiopathic in 37% of cases, severe bleeding was observed in 54% of patients treated with bypassing agents. Recombinant activated Factor VII (rFVIIa) was administered in 79% of cases and activated prothrombin complex concentrate (aPCC) in 10%, with no significant differences in haemostatic response and no thromboembolic complications. Occurrence of major bleeding showed no significant association with sex, age group, underlying condition, baseline Factor VIII activity or inhibitor titre at diagnosis. A total of 69% of patients were treated with corticosteroids alone, and 23% received a combination of corticosteroids and cyclophosphamide. Two patients died, six were lost to follow-up after partial remission, and one relapsed without bleeds after complete remission. Statistical analyses highlighted that the FVIII inhibitor titre > 20 BU was the only significant prognostic factor affecting time to complete remission. Conclusions: These observations emphasize the critical role of clinical suspicion and timely referral to experienced centres with adequate laboratory support for the effective management of AHA. Full article

Atherosclerosis as a multifactorial disease remains the first cause of death worldwide. Current oral lipid-lowering drugs (especially statins) reduce low-density lipoprotein cholesterol (LDLC) levels in the blood, but their clinical efficacy seems to be partially attributed to pleiotropic effects on different pathophysiologic factors of atherosclerosis extending beyond lipid-lowering properties such as anti-inflammatory, antithrombotic and antioxidative features. Novel drugs that interfere with proprotein convertase subtilisin/kexin type 9 (PCSK9) axis of LDL-C receptors (LDLRs) degradation, from the group of monoclonal antibodies (e.g., alirocumab, evolocumab) or small interfering RNA (siRNA), e.g., inclisiran, are effective in reducing LDLC as well. However, data depicting their antithrombotic and antiplatelet activity are scarce, whereas prothrombotic properties of PCSK9 are widely described. Thus, we performed a study to assess the effects of inclisiran on subclinical prothrombotic [fibrinogen, coagulation factor VIII (FVIII), plasminogen activator inhibitor-1 (PAI-1)] and platelet activation markers (platelet factor-4 (PF-4), soluble p-selectin (sCD62P)). Ten patients at high cardiovascular risk with concomitant heterozygous familial hypercholesterolemia (HeFH)—study group 1, and fourteen patients at very high cardiovascular risk without concomitant HeFH—study group 2, were recruited for the study. Lipid profile, subclinical prothrombotic and platelet activation markers were assessed at the beginning and after 3 months of therapy with inclisiran. During therapy, statistically significant reductions in both study groups were seen in total cholesterol levels (study group 1: from 287.6 ± 94.2 to 215.2 ± 89.1 (mg/dL), p = 0.022; study group 2: from 211.7 ± 52.7 to 147.6 ± 55.4 (mg/dL), p < 0.001) and LDL-c (study group 1: from 180.8 ± 73.3 to 114.7 ± 71.5 (mg/dL), p = 0.031; study group 2: from 129.6 ± 46.8 to 63.4 ± 43.6 (mg/dL), p < 0.001). Lipid profile changes were associated with significant decrease in the concentration of FVIII in both groups (study group 1: from 33.3 ± 22 to 22 ± 14.5 (ng/mL), p = 0.006; study group 2: from 37 ±16.9 to 29.3 ±16.4 (ng/mL), p = 0.002) and fibrinogen, but only in study group 2 (from 51.4 (33.2–72.7) to 42.6 (31.3–57.2) (µg/mL), p = 0.035). Among platelet activation markers, a significant decrease in PF-4 in study group 2 was noted (from 286 (272–295.5) to 272 (268–281.5) (ng/mL), p = 0.047). However, there were no statistically significant changes in PAI-1 and sCD62P throughout the study. In our study, inclisiran appeared to be an effective lipid-lowering drug in patients at high cardiovascular risk. Moreover, it was shown that beyond lipid-lowering properties, the drug may also partially affect thrombogenesis and platelet activation. Full article

Factor VIII (FVIII) interacts with Endoplasmic Reticulum (ER) chaperones Calnexin (CANX) and Calreticulin (CALR) and with ER-Golgi Intermediate Compartment (ERGIC) transporters, Lectin, mannose-binding 1 (LMAN1) and Multiple Coagulation Deficiency 2 (MCFD2). We previously reported that the Gamma-aminobutyric Acid Receptor-associated proteins (GABARAPs) also influence FVIII secretion. Here, we further investigated the intracellular dynamics of FVIII using single and double CRISPR/Cas9 Knockout (KO) models of the abovementioned chaperones as well as the GABARAP proteins in HEK293 cells expressing FVIII. Cellular pathways were manipulated by Brefeldin A (BFA), Chloroquine (CQ), a Rab7 inhibitor, and subjected to glucose starvation. The effect of each KO on FVIII secretion and organelle distribution was assessed by a two-stage chromogenic assay and immunofluorescence (IF) microscopy, prior and upon cell treatments. Using these approaches, we first observed distinct effects of each studied protein on FVIII trafficking. Notably, intracellular localization patterns revealed clustering of FVIII phenotypes in GABARAP^KO, CANX^KO, and CALR^KO cells together under both basal and treated conditions, an observation that was also reflected in their respective double KO combinations. Besides, a clear involvement of additional components of the endomembrane system was evident, specifically at the trans-Golgi space, as marked by FVIII colocalization with the Ras-like proteins in brain (Rab8 and Rab7) and with the Vesicle-Associated Membrane Protein (VAMP8), along with the observed impact of the selected cell treatments on FVIII phenotypes. These outcomes enhance our understanding of the molecular mechanisms regulating FVIII and pave the way for new perspectives, which could be further projected into FVIII replacement, cell and gene therapies. Full article

Background/Objectives: Childhood hemophilia, a hereditary bleeding disorder predominantly affecting males, arises due to gene mutations encoding clotting factors VIII or IX. Intracranial hemorrhage represents a significant and life-threatening complication in pediatric patients with hemophilia. The incidence of intracranial hemorrhage in children with hemophilia, although relatively low, is notably higher compared to the general pediatric population. Methods: In this study, the objective is to examine patients with hemophilia who have experienced intracranial hemorrhage retrospectively. This study is a multicenter, retrospective analysis using data from three tertiary care centers in a provincial city in Turkey. Data were obtained from the participants’ hospital records. The presence of inhibitors against FVIII in the participants and the prophylaxis used against them were included in the analysis. Trauma history was queried, with types of traumas examined, including traffic accidents, falls, and a traumatic vaginal delivery. The duration and causes of complaints among the participants were investigated. The causes of complaints were categorized as fever, hematoma, convulsions, loss of consciousness, and hemiparesis. The participants’ Physical Examination Findings were classified as fever, hematoma, and loss of consciousness. The duration of hospital stays was evaluated. The hemorrhage location was classified into five groups: parenchymal, subdural, scalp, subarachnoid, and multiple hemorrhagic foci. The recurrence of bleeding, the need for transfusion, surgical intervention, and mortality were also examined. Results: A significant difference was identified between the participants’ survival rates and age variables, as well as transfusion in <36 months. A total of 9 participants had spontaneous intracranial bleeding, 2 experienced cranial trauma as a result of traffic accidents, and 25 participants were exposed to head trauma due to falls. Of the remaining individuals, one suffered head trauma from a severe impact, and one had cranial trauma following a traumatic vaginal delivery. Fourteen participants required transfusion, and three underwent surgical intervention. Conclusions: According to the results of the statistical analyses, the variables Factor Level, Physical Examination Findings, Transfusion, Recurrent Bleeding, Inhibitor, and Prophylaxis were found to affect survival significantly. No significant relationship was determined between the other analyzed variables and survival. During our study, five of the participants examined died. Accordingly, the mortality rate identified in our study is 13.1%. Full article

This perspective discusses the critical role of laboratory assessments in assessing factor VIII (FVIII) inhibitors. These are auto- and alloantibodies that can develop against both endogenous and exogenous FVIII, respectively. Assessment for inhibitors represents a key part of the management of both congenital hemophilia A (CHA), an inherited deficiency, and acquired hemophilia A (AHA), an autoimmune condition. Both conditions pose significant bleeding risks, necessitating careful monitoring of FVIII levels and inhibitor presence and level. Laboratory assays, particularly the Bethesda assay, are essential for detecting these inhibitors and assessing their levels. The complexities of FVIII inhibitor kinetics may pose challenges to interpretation of assay results, such that even normal FVIII levels do not always exclude inhibitor presence. Clinical practice guidelines recommend ongoing monitoring of AHA/CHA patients until inhibitors are no longer detectable. Overall, timely laboratory evaluations are essential to optimizing treatment strategies for patients with hemophilia, aiming to improve patient outcomes and quality of life. We summarize our approach to the laboratory assessment of FVIII inhibitors, as reflecting our perspective and as informed by local practice. Full article

Hemophilia A is an X-linked disorder characterized by quantitative deficiency of coagulation factor VIII (FVIII) caused by pathogenic variants in the factor 8 (F8) gene. Our study’s primary objective was to identify genetic variants within the exonic region of F8 in 50 Colombian male participants with severe hemophilia A (HA). Whole-exome sequencing and bioinformatics analyses were performed, and bivariate analysis was used to evaluate the relationship between identified variants, disease severity, and inhibitor risk formation. Out of the 50 participants, 21 were found to have 17 different pathogenic F8 variants (var). It was found that 70% (var = 12) of them were premature truncation variants (nonsense, frameshift), 17.6% (var = 3) were missense mutations, and 11.7% (var = 2) were splice-site variants. Interestingly, 35% (var = 6) of the identified variants have not been previously reported in the literature. All patients with a history of positive inhibitors (n = 4) were found to have high-impact genetic variants (nonsense and frameshift). When investigating the relationship between variant location (heavy versus light chain) and specific inhibitor risk, 75% (n = 3) of the inhibitor participants were found to have variants located in the F8 light chain (p = 0.075), suggesting that conserved domains are associated with higher inhibitor risk. In summary, we identified genetic variants within the F8 that can possibly influence inhibitor development in Colombian patients with severe HA. Our results provide a basis for future studies and the development of further personalized treatment strategies in this population. Full article

Introduction: Apart from the well-known fact that hyperthyroidism induces multiple prothrombotic disorders, there is no consensus in clinical practice as to the impact of hyperthyroidism on the risk of thrombosis. The aim of this study was to examine the various hemostatic and immunologic parameters in patients with hyperthyroidism. Methods: Our study consists of a total of 200 patients comprised of 64 hyperthyroid patients, 68 hypothyroid patients, and 68 euthyroid controls. Patient thyroid status was determined with standard tests. Detailed hemostatic parameters and cardiolipin antibodies of each patient were determined. Results: The values of factor VIII (FVIII), the Von Willebrand factor (vWF), fibrinogen, plasminogen activator inhibitor-1 (PAI-1), and anticardiolipin antibodies of the IgM class were significantly higher in the hyperthyroid patients than in the hypothyroid patients and euthyroid controls. The rate of thromboembolic manifestations was much higher in hyperthyroid patients (6.25%) than in hypo-thyroid patients (2.9%) and euthyroid controls (1.4%). Among hyperthyroid patients with an FVIII value of ≥1.50 U/mL, thrombosis was recorded in 8.3%, while in hyperthyroid patients with FVIII value ≤ 1.50 U/mL the occurrence of thrombosis was not recorded. The incidence of atrial fibrillation (AF) was significantly higher (8.3%) in the hyperthyroid patients compared to the hypothyroid patients (1.5%) and euthyroid controls (0%). Conclusions: High levels of FVIII, vWF, fibrinogen, PAI-1, and anticardiolipin antibodies along with other hemostatic factors contribute to the presence of a hypercoaguable state in patients with hyperthyroidism. The risk of occurrence of thrombotic complications is especially pronounced in patients with a level of FVIII exceeding 150% and positive anticardiolipin antibodies of the IgM class. Patients with AF are at particularly high risk of thrombotic complications due to a hyperthyroid prothrombotic milieu. Full article

Hemophilia A is a hemorrhagic disorder caused by insufficient or inadequate coagulation factor VIII activity. Two different forms are described: congenital, hereditary X-linked, and acquired. Acquired hemophilia A (AHA) is a rare condition and it is defined by the production of autoantibodies neutralizing factor VIII, known as inhibitors. We report the case of a 72-year-old man with a clinical diagnosis of AHA after SARS-CoV-2 infection, which has been described in association with several hematological complications. SARS-CoV-2 infection could represent the immunological trigger for the development of autoantibodies. In our patient, SARS-CoV-2 infection preceded the hemorrhagic complications by 15 days. This lag time is in line with the other cases reported and compatible with the development of an intense immune response with autoantibody production. It is possible that since our patient was affected by type 1 diabetes mellitus, he was more prone to an immune system pathological response against self-antigens. A prompt, appropriate therapeutic intervention with activated recombinant factor VII administration and cyclophosphamide has led to rapid remission of clinical and laboratory findings. Full article

Hemophilia is a genetic disorder linked to the sex chromosomes, resulting in impaired blood clotting due to insufficient intrinsic coagulation factors. There are approximately one million individuals worldwide with hemophilia, with hemophilia A being the most prevalent form. The current treatment for hemophilia A involves the administration of clotting factor VIII (FVIII) through regular and costly injections, which only provide temporary relief and pose inconveniences to patients. In utero transplantation (IUT) is an innovative method for addressing genetic disorders, taking advantage of the underdeveloped immune system of the fetus. This allows mesenchymal stromal cells to play a role in fetal development and potentially correct genetic abnormalities. The objective of this study was to assess the potential recovery of coagulation disorders in FVIII knockout hemophilia A mice through the administration of human amniotic fluid mesenchymal stromal cells (hAFMSCs) via IUT at the D14.5 fetal stage. The findings revealed that the transplanted human cells exhibited fusion with the recipient liver, with a ratio of approximately one human cell per 10,000 mouse cells and produced human FVIII protein in the livers of IUT-treated mice. Hemophilia A pups born to IUT recipients demonstrated substantial improvement in their coagulation issues from birth throughout the growth period of up to 12 weeks of age. Moreover, FVIII activity reached its peak at 6 weeks of age, while the levels of FVIII inhibitors remained relatively low during the 12-week testing period in mice with hemophilia. In conclusion, the results indicated that prenatal intrahepatic therapy using hAFMSCs has the potential to improve clotting issues in FVIII knockout mice, suggesting it as a potential clinical treatment for individuals with hemophilia A. Full article

Acquired Hemophilia A (AHA) is a rare autoimmune disorder characterized by the onset of a sudden and unexpected bleeding episode in a patient with no personal or family history of bleeding diathesis, and with a typical laboratory feature, i.e., a prolonged activated partial thromboplastin time that is not otherwise explained. This bleeding disorder is caused by autoantibodies directed against the coagulation factor VIII (FVIII). AHA is idiopathic in 50% of cases and is secondary to well-defined diseases in the remaining 50%. AHA affects elderly patients although it has also been observed in the post-partum period. Bleeding manifestations are heterogeneous, ranging from mild to life-threatening bleeds involving limbs and organs. Severe bleeding with a significant decrease in hemoglobin levels must be promptly and adequately treated in order to avoid a worsening of the hemorrhages and their complications. According to international recommendations, the bypass agents (i.e., activated prothrombin complex concentrate and activated recombinant factor VII) and the replacement therapy with recombinant porcine FVIII are considered as the first-line therapy for bleeding control, due to their proven clinical efficacy. Plasma-derived or recombinant FVIII concentrates could be used as second-line treatments. Emicizumab may represent a valid and interesting therapeutic option for prophylaxis of bleeding recurrences. Full article

The risk of lung exposure to silica nanoparticles (SiNPs) and related lung inflammatory injury is increasing with the wide application of SiNPs in a variety of industries. A growing body of research has revealed that cyclooxygenase (COX)-2/prostaglandin E₂ (PGE₂) up-regulated by SiNP toxicity has a role during pulmonary inflammation. The detailed mechanisms underlying SiNP-induced COX-2 expression and PGE₂ synthesis remain unknown. The present study aims to dissect the molecular components involved in COX-2/PGE₂ up-regulated by SiNPs in human pulmonary alveolar epithelial cells (HPAEpiCs) which are one of the major targets while SiNPs are inhaled. In the present study, we demonstrated that SiNPs induced COX-2 expression and PGE₂ release, which were inhibited by pretreatment with a reactive oxygen species (ROS) scavenger (edaravone) or the inhibitors of proline-rich tyrosine kinase 2 (Pyk2, PF-431396), epidermal growth factor receptor (EGFR, AG1478), phosphatidylinositol 3-kinase (PI3K, LY294002), protein kinase B (Akt, Akt inhibitor VIII), p38 mitogen-activated protein kinase (MAPK) (p38 MAPK inhibitor VIII), c-Jun N-terminal kinases (JNK)1/2 (SP600125), Forkhead Box O1 (FoxO1, AS1842856), and activator protein 1 (AP-1, Tanshinone IIA). In addition, we also found that SiNPs induced ROS-dependent Pyk2, EGFR, Akt, p38 MAPK, and JNK1/2 activation in these cells. These signaling pathways induced by SiNPs could further cause c-Jun and FoxO1 activation and translocation from the cytosol to the nucleus. AP-1 and FoxO1 activation could increase COX-2 and PGE₂ levels induced by SiNPs. Finally, the COX-2/PGE₂ axis might promote the inflammatory responses in HPAEpiCs. In conclusion, we suggested that SiNPs induced COX-2 expression accompanied by PGE₂ synthesis mediated via ROS/Pyk2/EGFR/PI3K/Akt/p38 MAPK- and JNK1/2-dependent FoxO1 and AP-1 activation in HPAEpiCs. Full article

Newborns are the most vulnerable patients for thrombosis development among all children, with critically ill and premature infants being in the highest risk group. The upward trend in the rate of neonatal thrombosis could be attributed to progress in the treatment of severe neonatal conditions and the increased survival in premature babies. There are physiological differences in the hemostatic system between neonates and adults. Neonates differ in concentrations and rate of synthesis of most coagulation factors, turnover rates, the ability to regulate thrombin and plasmin, and in greater variability compared to adults. Natural inhibitors of coagulation (protein C, protein S, antithrombin, heparin cofactor II) and vitamin K-dependent coagulation factors (factors II, VII, IX, X) are low, but factor VIII and von Willebrand factor are elevated. Newborns have decreased fibrinolytic activity. In the healthy neonate, the balance is maintained but appears more easily converted into thrombosis. Neonatal hemostasis has less buffer capacity, and almost 95% of thrombosis is provoked. Different triggering risk factors are responsible for thrombosis in neonates, but the most important risk factors for thrombosis are central catheters, fluid fluctuations, liver dysfunction, and septic and inflammatory conditions. Low-molecular-weight heparins are the agents of choice for anticoagulation. Full article