Clinical significance of assessing ADAMTS-13 and von Willebrand factor level in COVID-19 convalescent pregnant women.

Introduction. Coronavirus infection is associated with severe endotheliopathy, thromboinflammation and immunothrombosis leading to excessive release of von Willebrand factor (vWF) multimers from Weibel-Palade bodies, which can affect activity of ADAMTS-13 metalloproteinase (a disintegrin and metalloproteinase with thrombospondin type 1 motif, member 13) and the ADAMTS-13/vWF axis previously shown by us to be altered in non-pregnant women with severe COVID-19. Aim(s): to study a clinical role of hemostasis activation particularly ADAMTS-13/vWF axis in pregnant women after COVID-19. Materials and Methods. A prospective case-control study was conducted with pregnant women (n = 135) divided into 3 groups: group 1 included 45 women with prior COVID-19 during pregnancy, group 2 - 45 women in the acute phase of the infection during pregnancy, group 3 - 45 healthy pregnant women. The level of vWF and ADAMTS-13 was assessed in all patients. Results. The concentration of vWF antigen (vWF:Ag) in the acute period of the disease in pregnant women with COVID-19 was significantly higher compared to the control group (p < 0.001). ADAMTS-13 level in pregnant women after COVID-19 did not differ from that of in control group, while vWF level was significantly higher in 66.7 % (30/45). The ADAMTS-13/vWF ratio was increased and significantly differed both in pregnant patients during the acute period of the disease (p < 0.001) and pregnant women after infection (p = 0.0002) compared with the control group. Conclusion. Our results show that endotheliopathy was prominently manifested in pregnant women with COVID-19 and persisted for several months after disease. The ADAMTS-13/vWF ratio determines the pathway functioning, the risk of microcirculation disorders and clinical complications.Copyright © 2023 Vestnik Sankt-Peterburgskogo Universiteta, Yazyk i Literatura. All rights reserved.

Case report: COVID-19-associated refractory thrombotic thrombocytopenic purpura complicated with Guillain-Barré syndrome.

Thrombotic thrombocytopenic purpura (TTP), a rare and lethal thrombotic microangiopathy, is an autoimmune disease that can be triggered by viral infections such as COVID-19. This condition is characterized by hemolytic microangiopathy, thrombocytopenia, and neurologic alterations, possibly accompanied by fever and renal damage. Moreover, more than 220 patients with Guillain-Barré syndrome (GBS) have been reported in association with the COVID-19 infection. In this report, we present a case of a patient who developed refractory TTP complicated by GBS following a SARS-CoV-2 infection. We aimed to highlight the importance of accurately diagnosing neurological complications associated with a COVID-19 infection and to demonstrate our strategies for treating a patient with COVID-19 infection-related refractory TTP complicated by GBS.

Erratum: Immune-mediated thrombotic thrombocytopenic purpura following mRNA-based COVID-19 vaccine BNT162b2: Case report and mini-review of the literature.

[This corrects the article DOI: 10.3389/fmed.2022.890661.].

Functioning of the ADAMTS-13/vWF axis and its clinical significance

Advances in biology have allowed us to substantially deepen our knowledge about hemostasis functioning both in health and disease. ADAMTS-13 (a disintegrin and metalloproteinase with thrombospondin type 1 motif, member 13) and von Willebrand factor (vWF) are components of the hemostasis system, which physiological interaction holds an important place in maintaining homeostasis. ADAMTS-13 is a metalloproteinase mainly acting to release vWF fragments into the blood plasma, as well as regulating its activity by cleaving ultra-large vWF multimers (UL-vWF) into smaller and less active forms. The study of such factors is of great clinical importance, since a decrease in ADAMTS-13 activity and an increase in vWF level can be predictors of microcirculatory disorders that play an important role in developing multiple organ failure. However, very few and fully contradictory studies devoted to the physiological aspects of the ADAMTS-13/vWF axis functioning in the mother-fetus system are available, therefore requiring to be further investigated.Copyright © 2023 Russian Journal of Forensic Medicine. All rights reserved.

Clinical significance of assessing ADAMTS-13 and von Willebrand factor level in COVID-19 convalescent pregnant women

Introduction. Coronavirus infection is associated with severe endotheliopathy, thromboinflammation and immunothrombosis leading to excessive release of von Willebrand factor (vWF) multimers from Weibel-Palade bodies, which can affect activity of ADAMTS-13 metalloproteinase (a disintegrin and metalloproteinase with thrombospondin type 1 motif, member 13) and the ADAMTS-13/vWF axis previously shown by us to be altered in non-pregnant women with severe COVID-19. Aim: to study a clinical role of hemostasis activation particularly ADAMTS-13/vWF axis in pregnant women after COVID-19. Materials and Мethods. A prospective case-control study was conducted with pregnant women (n = 135) divided into 3 groups: group 1 included 45 women with prior COVID-19 during pregnancy, group 2 - 45 women in the acute phase of the infection during pregnancy, group 3 - 45 healthy pregnant women. The level of vWF and ADAMTS-13 was assessed in all patients. Results. The concentration of vWF antigen (vWF:Ag) in the acute period of the disease in pregnant women with COVID-19 was significantly higher compared to the control group (p < 0.001). ADAMTS-13 level in pregnant women after COVID-19 did not differ from that of in control group, while vWF level was significantly higher in 66.7 % (30/45). The ADAMTS-13/vWF ratio was increased and significantly differed both in pregnant patients during the acute period of the disease (p < 0.001) and pregnant women after infection (p = 0.0002) compared with the control group. Conclusion. Our results show that endotheliopathy was prominently manifested in pregnant women with COVID-19 and persisted for several months after disease. The ADAMTS-13/vWF ratio determines the pathway functioning, the risk of microcirculation disorders and clinical complications. © 2023 Vestnik Sankt-Peterburgskogo Universiteta, Yazyk i Literatura. All rights reserved.

An Overview of Laboratory Testing for ADAMTS13.

ADAMTS13 (a disintegrin and metalloproteinase with a thrombospondin type 1 motif, member 13) is also called von Willebrand factor (VWF) cleaving protease (VWFCP). ADAMTS13 acts to cleave VWF multimers and thus reduce plasma VWF activity. In the absence of ADAMTS13 (i.e., in thrombotic thrombocytopenia purpura, TTP), plasma VWF can accumulate, in particular as "ultra-large" VWF multimers, and this can lead to thrombosis. Relative deficiencies in ADAMTS13 can also occur in a variety of other conditions, including secondary thrombotic microangiopathies (TMA). Of contemporary interest, COVID-19 (coronavirus disease 2019) may also be associated with relative reduction of ADAMTS13 and also pathological accumulation of VWF, with this likely contributing to the thrombosis risk seen in affected patients. Laboratory testing for ADAMTS13 can assist in the diagnosis of these disorders (i.e., TTP, TMA), as well as in their management, and can be achieved using a variety of assays. This chapter therefore provides an overview of laboratory testing for ADAMTS13 and the value of such testing to assist the diagnosis and management of associated disorders.

Automated and Rapid ADAMTS13 Testing Using Chemiluminescence: Utility for Identification or Exclusion of TTP and Beyond.

Thrombotic thrombocytopenic purpura (TTP) is a prothrombotic condition caused by a significant deficiency of the enzyme, ADAMTS13 (a disintegrin and metalloproteinase with a thrombospondin type 1 motif, member 13). In the absence of adequate levels of ADAMTS13 (i.e., in TTP), plasma VWF accumulates, in particular as "ultra-large" VWF multimers, and this leads to pathological platelet aggregation and thrombosis. In addition to TTP, ADAMTS13 may be mildly to moderately reduced in a range of other conditions, including secondary thrombotic microangiopathies (TMA) such as those caused by infections (e.g., hemolytic uremic syndrome (HUS)), liver disease, disseminated intravascular coagulation (DIC), and sepsis, during acute/chronic inflammatory conditions, and sometimes also in COVID-19 (coronavirus disease 2019)). ADAMTS13 can be detected by a variety of techniques, including ELISA (enzyme-linked immunosorbent assay), FRET (fluorescence resonance energy transfer) and by chemiluminescence immunoassay (CLIA). The current report describes a protocol for assessment of ADAMTS13 by CLIA. This protocol reflects a rapid test able to be performed within 35 min on the AcuStar instrument (Werfen/Instrumentation Laboratory), although certain regional approvals may also permit this testing to be performed on a BioFlash instrument from the same manufacturer.

Von Willebrand factor and the thrombophilia of severe COVID-19: in situ evidence from autopsies.

Background: COVID-19 is accompanied by a hypercoagulable state and characterized by microvascular and macrovascular thrombotic complications. In plasma samples from patients with COVID-19, von Willebrand factor (VWF) levels are highly elevated and predictive of adverse outcomes, especially mortality. Yet, VWF is usually not included in routine coagulation analyses, and histologic evidence of its involvement in thrombus formation is lacking. Objectives: To determine whether VWF, an acute-phase protein, is a bystander, ie, a biomarker of endothelial dysfunction, or a causal factor in the pathogenesis of COVID-19. Methods: We compared autopsy samples from 28 patients with lethal COVID-19 to those from matched controls and systematically assessed for VWF and platelets by immunohistochemistry. The control group comprised 24 lungs, 23 lymph nodes, and 9 hearts and did not differ significantly from the COVID-19 group in age, sex, body mass index (BMI), blood group, or anticoagulant use. Results: In lungs, assessed for platelets by immunohistochemistry for CD42b, microthrombi were more frequent in patients with COVID-19 (10/28 [36%] vs 2/24 [8%]; P = .02). A completely normal pattern of VWF was rare in both groups. Accentuated endothelial staining was found in controls, while VWF-rich thrombi were only found in patients with COVID-19 (11/28 [39%] vs 0/24 [0%], respectively; P < .01), as were NETosis thrombi enriched with VWF (7/28 [25%] vs 0/24 [0%], respectively; P < .01). Forty-six percent of the patients with COVID-19 had VWF-rich thrombi, NETosis thrombi, or both. Trends were also seen in pulmonary draining lymph nodes (7/20 [35%] vs 4/24 [17%]; P = .147), where the overall presence of VWF was very high. Conclusion: We provide in situ evidence of VWF-rich thrombi, likely attributable to COVID-19, and suggest that VWF may be a therapeutic target in severe COVID-19.

Clinical significance of assessing ADAMTS-13 and von Willebrand factor level in COVID-19 convalescent pregnant women.

Introduction. Coronavirus infection is associated with severe endotheliopathy, thromboinflammation and immunothrombosis leading to excessive release of von Willebrand factor (vWF) multimers from Weibel-Palade bodies, which can affect activity of ADAMTS-13 metalloproteinase (a disintegrin and metalloproteinase with thrombospondin type 1 motif, member 13) and the ADAMTS-13/vWF axis previously shown by us to be altered in non-pregnant women with severe COVID-19. Aim(s): to study a clinical role of hemostasis activation particularly ADAMTS-13/vWF axis in pregnant women after COVID-19. Materials and Methods. A prospective case-control study was conducted with pregnant women (n = 135) divided into 3 groups: group 1 included 45 women with prior COVID-19 during pregnancy, group 2 - 45 women in the acute phase of the infection during pregnancy, group 3 - 45 healthy pregnant women. The level of vWF and ADAMTS-13 was assessed in all patients. Results. The concentration of vWF antigen (vWF:Ag) in the acute period of the disease in pregnant women with COVID-19 was significantly higher compared to the control group (p < 0.001). ADAMTS-13 level in pregnant women after COVID-19 did not differ from that of in control group, while vWF level was significantly higher in 66.7 % (30/45). The ADAMTS-13/vWF ratio was increased and significantly differed both in pregnant patients during the acute period of the disease (p < 0.001) and pregnant women after infection (p = 0.0002) compared with the control group. Conclusion. Our results show that endotheliopathy was prominently manifested in pregnant women with COVID-19 and persisted for several months after disease. The ADAMTS-13/vWF ratio determines the pathway functioning, the risk of microcirculation disorders and clinical complications.Copyright © 2023 Vestnik Sankt-Peterburgskogo Universiteta, Yazyk i Literatura. All rights reserved.

Immune and Hereditary Thrombotic Thrombocytopenic Purpura: Can ADAMTS13 Deficiency Alone Explain the Different Clinical Phenotypes?

Thrombotic thrombocytopenic purpura (TTP) is a thrombotic microangiopathy caused by a hereditary or immune-mediated deficiency of the enzyme ADAMTS13 (a disintegrin and metalloproteinase with a thrombospondin type 1 motif, member 13). TTPs are caused by the following pathophysiological mechanisms: (1) the presence of inhibitory autoantibodies against ADAMTS13; and (2) hereditary mutations of the ADAMTS13 gene, which is present on chromosome 9. In both syndromes, TTP results from a severe deficiency of ADAMTS13, which is responsible for the impaired proteolytic processing of high-molecular-weight von Willebrand factor (HMW-VWF) multimers, which avidly interact with platelets and subendothelial collagen and promote tissue and multiorgan ischemia. Although the acute presentation of the occurring symptoms in acquired and hereditary TTPs is similar (microangiopathic hemolytic anemia, thrombocytopenia, and variable ischemic end-organ injury), their intensity, incidence, and precipitating factors are different, although, in both forms, a severe ADAMTS13 deficiency characterizes their physiopathology. This review is aimed at exploring the possible factors responsible for the different clinical and pathological features occurring in hereditary and immune-mediated TTPs.

Effects of convalescent plasma infusion on the ADAMTS13-von Willebrand factor axis and endothelial integrity in patients with severe and critical COVID-19.

Background: Convalescent plasma infusion (CPI) was given to patients with COVID-19 during the early pandemic with mixed therapeutic efficacy. However, the impacts of CPI on the ADAMTS13-von Willebrand factor (VWF) axis and vascular endothelial functions are not known. Objectives: To determine the impacts of CPI on the ADAMTS13-VWF axis and vascular endothelial functions. Methods: Sixty hospitalized patients with COVID-19 were enrolled in the study; 46 received CPI and 14 received no CPI. Plasma ADAMTS13 activity, VWF antigen, endothelial syndecan-1, and soluble thrombomodulin (sTM) were assessed before and 24 hours after treatment. Results: Patients with severe and critical COVID-19 exhibited significantly lower plasma ADAMTS13 activity than the healthy controls. Conversely, these patients showed a significantly increased VWF antigen. This resulted in markedly reduced ratios of ADAMTS13 to VWF in these patients. The levels of plasma ADAMTS13 activity in each patient remained relatively constant throughout hospitalization. Twenty-four hours following CPI, plasma ADAMTS13 activity increased by ∼12% from the baseline in all patients and ∼21% in those who survived. In contrast, plasma levels of VWF antigen varied significantly over time. Patients who died exhibited a significant reduction of plasma VWF antigen from the baseline 24 hours following CPI, whereas those who survived did not. Furthermore, patients with severe and critical COVID-19 showed significantly elevated plasma levels of syndecan-1 and sTM, similar to those found in patients with immune thrombotic thrombocytopenic purpura. Both syndecan-1 and sTM levels were significantly reduced 24 hours following CPI. Conclusion: Our results demonstrate the relative deficiency of plasma ADAMTS13 activity and endothelial damage in patients with severe and critical COVID-19, which could be modestly improved following CPI therapy.

Prolonged Exposure to Caplacizumab as Rescue Therapy in Refractory Immune Thrombotic Thrombocytopenic Purpura.

We describe a case of refractory thrombotic thrombocytopenic purpura (7 lines of therapy) in which caplacizumab was used over a 6-month period as rescue therapy. Caplacizumab maintained the patient in clinical remission until successful immunosuppression was achieved resulting in normal ADAMTS13 levels. This case illustrates the utility of caplacizumab therapy in treating refractory TTP.

Missense Variants of von Willebrand Factor in the Background of COVID-19 Associated Coagulopathy.

COVID-19 associated coagulopathy (CAC), characterized by endothelial dysfunction and hypercoagulability, evokes pulmonary immunothrombosis in advanced COVID-19 cases. Elevated von Willebrand factor (vWF) levels and reduced activities of the ADAMTS13 protease are common in CAC. Here, we aimed to determine whether common genetic variants of these proteins might be associated with COVID-19 severity and hemostatic parameters. A set of single nucleotide polymorphisms (SNPs) in the vWF (rs216311, rs216321, rs1063856, rs1800378, rs1800383) and ADAMTS13 genes (rs2301612, rs28729234, rs34024143) were genotyped in 72 COVID-19 patients. Cross-sectional cohort analysis revealed no association of any polymorphism with disease severity. On the other hand, analysis of variance (ANOVA) uncovered associations with the following clinical parameters: (1) the rs216311 T allele with enhanced INR (international normalized ratio); (2) the rs1800383 C allele with elevated fibrinogen levels; and (3) the rs1063856 C allele with increased red blood cell count, hemoglobin, and creatinine levels. No association could be observed between the phenotypic data and the polymorphisms in the ADAMTS13 gene. Importantly, in silico protein conformational analysis predicted that these missense variants would display global conformational alterations, which might affect the stability and plasma levels of vWF. Our results imply that missense vWF variants might modulate the thrombotic risk in COVID-19.

Decreased protein C activity, lower ADAMTS13 antigen and free protein S levels accompanied by unchanged thrombin generation potential in hospitalized COVID-19 patients.

INTRODUCTION: COVID-19 is associated with an increased thromboembolic risk. However, the mechanisms triggering clot formation in those patients remain unknown. PATIENTS AND METHODS: In 118 adult Caucasian severe but non-critically ill COVID-19 patients (median age 58 years; 73 % men) and 46 controls, we analyzed in vitro plasma thrombin generation profile (calibrated automated thrombogram [CAT assay]) and investigated thrombophilia-related factors, such as protein C and antithrombin activity, free protein S level, presence of antiphospholipid antibodies and factor V Leiden R506Q and prothrombin G20210A mutations. We also measured circulating von Willebrand factor (vWF) antigen and a disintegrin and metalloproteinase with a thrombospondin type 1 motif, member 13 (ADAMTS13) antigen and activity. In patients, blood samples were collected on admission to the hospital before starting any therapy, including heparin. Finally, we examined the relationship between observed alterations and disease follow-up, such as thromboembolic complications. RESULTS: COVID-19 patients showed 17 % lower protein C activity, 22 % decreased free protein S levels, and a higher prevalence of positive results for IgM anticardiolipin antibodies. They also had 151 % increased vWF, and 27 % decreased ADAMTS13 antigens compared with controls (p < 0.001, all). On the contrary, thrombin generation potential was similar to controls. In the follow-up, pulmonary embolism (PE) occurred in thirteen (11 %) patients. They were characterized by a 55 % elevated D-dimer (p = 0.04) and 2.7-fold higher troponin I (p = 0.002) during hospitalization and 29 % shorter time to thrombin peak in CAT assay (p = 0.009) compared to patients without PE. CONCLUSIONS: In COVID-19, we documented prothrombotic abnormalities of peripheral blood. PE was characterized by more dynamic thrombin generation growth in CAT assay performed on admittance to the hospital.

Prognostic value of von Willebrand factor in clinical practice

The von Willebrand factor (vWF) is a multimeric plasma glycoprotein, which quantification has important prognostic value. The current literature review demonstrates a relationship between the disease severity and vWF level. For example, von Willebrand disease is characterized by a quantitative/qualitative genetic vWF deficiency resulting in potentially developed massive bleeding, which knowledge can prevent development of formidable complications. We should also not forget about an opportunity of developing acquired Willebrand syndrome most often occurring in response to autoimmune diseases. A marked vWF increase during pregnancy may evidence about developing preeclampsia, whereas in newborns exposed to additional risk factors, it can lead to thrombosis. In cancer patients, a substantially elevated vWF level correlates with low survival, especially in those with ovarian cancer, glioblastomas, esophageal and lung cancer. The emergence of a novel coronavirus infection COVID-19 allowed us to take a fresh look at prognostic value of vWF, because numerous studies show that increased blood plasma vWF:Ag is associated with more adverse outcome in patients with COVID-19. Here, we demonstrate an importance of determining vWF level, because early diagnostics and treatment can improve the outcomes of all such patients. Copyright © 2022 Obstetrics, Gynecology and Reproduction. All rights reserved.

COVID-19-Induced Thrombocytopenia: A Brief Literature Review and Case Report.

With sporadic surges of COVID-19, medical professionals are continuously expanding their knowledge and contributing to medical literature through experiences and research. We present a rare case of a 65-year-old Hispanic male diagnosed with COVID-19-induced immune thrombocytopenic purpura (ITP). Commonly seen in cases with COVID-19-vaccine-induced thrombocytopenia, there are very few published case reports of ITP as a result of the COVID-19 virus.

[Acquired thrombotic thrombocytopenic purpura following COVID-19].

COVID-19 often contributes to thrombus formation in microvessels, resulting in damaged vital organs. In this study, we report a case of COVID-19 associated with acquired thrombotic thrombocytopenic purpura (TTP). A 44-year-old man with a history of systemic lupus erythematosus presented with COVID-19 and concomitant hemolytic anemia and a marked thrombocytopenia. The patient was diagnosed with acquired TTP because ADAMTS13 inhibitor was detected and ADAMTS13 activity below the sensitivity level. The patient developed agitated neuropsychiatric symptoms, such as aphasia, disorientation, and delirium, which improved after a plasma exchange, prednisolone, and rituximab administration. Only a few reports have revealed COVID-19 with TTP, and this is the first case in Japan. Although acquired TTP rarely develops, it is an important complication of COVID-19, and thus, it should be promptly diagnosed and treated as soon as possible.

Von Willebrand Factor and Myeloperoxidase as Laboratory Predictive Markers of In-Hospital Survival in Severe COVID-19 Patients

Background. The severe acute respiratory syndrome of the SARS-CoV-2 virus-mediated coronavirus disease 2019 (COVID-19) highlighted the central role of immunothrombosis. Severe endothelial damage with the release of unusually large multimers of von Willebrand factor (vWF) and subsequent consumption of ADAMTS-13 is described during severe COVID-19. The activation of innate immune cells among which neutrophils contribute to the formation of extracellular neutrophil traps (NETs) and to the release of myeloperoxidase (MPO) potentially contributing to the spread of inflammation and microvascular thrombosis. Objective - to evaluate the ability of vWF, ADAMTS-13 and MPO to predict in-hospital mortality in severe COVID-19 patients needing mechanical ventilation. Methods. We performed a one-center observational study of 79 severe COVID-19 patients entering intensive care unit for mechanical ventilation, examining vWF, ADAMTS-13 and MPO among other potential predictors for in-hospital death. Results. After multivariate analysis, vWF antigen (vWF:Ag) and MPO antigen (MPO:Ag) were finally the single two parameters which increasing values were independently associated with non-survival;vWF:Ag (U/dL): adjusted OR 3.360, 95% CI 1.562-7.228, p = 0.0019;MPO:Ag (ng/ml): adjusted OR 1.062, 95% CI 1.024-1.101, p = 0.0011. From these results a simplified mortality score was derived and patients categorized as having a score value higher or lower that the median value of the score: a high score value was associated with a lower cumulative survival rate (p < 0.0001), 50% of the cases being dead at day 13 post-hospital admission. Conclusions. In severe COVID-19 necessitating mechanical ventilation, increasing values of MPO activity and of vWF antigen tested at admission are associated with poor survival. Copyright © 2022 Izdatel'stvo Meditsina. All rights reserved.

A Race against the Clock: A Case Report and Literature Review Concerning the Importance of ADAMTS13 Testing in Diagnosis and Management of Thrombotic Thrombocytopenic Purpura during Pregnancy.

Thrombocytopenic purpura (TTP) is a rare, potentially fatal pathology characterized by microangiopathic thrombotic syndrome and caused by an acute protease deficiency of von Willebrand factor, ADAMTS13. Moreover, ADAMTS13 deficiency promotes microthrombosis led by the persistence of ultra-large VWF multimers in the blood circulation. According to the few studies involving pregnant participants, the heterogeneity of manifestations has made this pathology difficult to diagnose, with an unexpected occurrence and increased risk of maternal and fetal morbidity and mortality. We reported on the case of a 28-year-old pregnant woman with an obstetric score of G2P0 who presented to the obstetrics and gynecology department of our clinic with the complaint of minimal vaginal bleeding. The evolution of our case was severe and life-threatening, a "race against the clock", with our goal being to emphasize the importance and difficulty of diagnosing TTP in the absence of specific symptomatology. We faced a lack of technological support for a correct and complete diagnosis, and the first manifestation of this disease was the intrauterine death of the fetus. After completing all the necessary procedures, the placental tissue was sent for further histopathological evaluation. We highlighted the importance of monitoring ADAMTS13 for relapses monthly, with prophylaxis being essential for maternal and fetal mortality and morbidity.