Thrombocytopenic conditions-autoimmunity and hypercoagulability: commonalities and differences in ITP, TTP, HIT, and APS

Catastrophic Antiphospholipid Syndrome

Unlike classic APS, CAPS causes multiple microthrombosis due to an increased inflammatory response, known as a "thrombotic storm". CAPS typically develops after infection, trauma, or surgery and begins with the following symptoms: fever, thrombocytopenia, muscle weakness, visual and cognitive disturbances, abdominal pain, renal failure, and disseminated intravascular coagulation. Although the presence of antiphospholipid antibodies in the blood is one of the diagnostic criteria, the level of these antibodies can fluctuate significantly, which complicates the diagnostic process and can lead to erroneous interpretation of rapidly developing symptoms. Triple therapy is often used to treat CAPS, which includes the use of anticoagulants, plasmapheresis, and high doses of glucocorticosteroids and, in some cases, additional intravenous immunoglobulins. The use of LMWH is recommended as the drug of choice due to its anti-inflammatory and anticoagulant properties. CAPS is a multifactorial disease that requires not only an interdisciplinary approach but also highly qualified medical care, adequate and timely diagnosis, and appropriate prevention in the context of relapse or occurrence of the disease. Improved new clinical protocols and education of medical personnel regarding CAPS can significantly improve the therapeutic approach and reduce mortality rates.

Early treatment of rituximab combined with eltrombopag for secondary thrombocytopenic purpura in rheumatoid arthritis: A case report

RATIONALE

Secondary immune thrombocytopenic purpura (ITP) is also known as acquired thrombocytopenic purpura, autoimmune disease is usually one of the important causes. There are few reports about treatment of refractory thrombocytopenic purpura in rheumatoid arthritis (RA). We report a case of refractory ITP in which changes in platelet-related markers with therapeutic agents are worthy of the attention of clinicians.

PATIENT CONCERNS

A 69-year-old woman admitted for ecchymosis on the neck and arms for 15 days presented to our hospital. She was diagnosed with RA 5 years ago.

DIAGNOSIS

The diagnosis met the American College of Rheumatology/European League Against Rheumatism 2010 classification criteria. The disease activity score 28 (DAS-28) was 4.6, indicating that the disease activity was moderate.

INTERVENTIONS

Treatment with first-line therapies and second-line treatment--eltrombopag (EPAG) were ineffective. Therefore, we performed rituximab combined with a low dose of EPAG.

OUTCOMES

The patient received 2 cycles of rituximab combined with EPAG, and reported no new petechiae on her buccal mucosa and limbs during follow-up.

LESSONS

This case suggests that early treatment of rituximab combined with EPAG is beneficial to patients with refractory ITP in RA. In terms of disease dynamic monitoring, immature platelet fraction (IPF) may be an auxiliary indicator for predicting efficacy, but its significance needs further study.

Sequential Immune Thrombocytopenia (ITP) and Thrombotic Thrombocytopenic Purpura (TTP) in an Elderly Male Patient with Primary Sjogren's Syndrome: When in Doubt, Use the PLASMIC Score

Introduction

Thrombotic thrombocytopenic purpura (TTP) is a rare, life-threatening thrombotic microangiopathy due to an acquired autoantibody to ADAMTS13 that requires a boutique treatment, urgent plasma exchange. Thus, TTP is often termed a "cannot miss" diagnosis.

Case

We report a patient with TTP who had a history of immune thrombocytopenia (ITP), had atypical demographics for TTP, and had also met criteria for primary Sjogren's syndrome. This exceedingly rare combination presented a temptation to dismiss TTP as a diagnosis. Discussion. Our case further demonstrates the practical utility of using the PLASMIC score as a tool that can help identify patients with TTP even when the patient has statistically rare characteristics.

Coagulopathy in SARS-CoV-2 Infected Patients: Implication for the Management of COVID-19

COVID-19 disease has led to an extraordinary inclusive health crisis globally. Elevation of D-dimer is the major remarkable abnormal coagulation test in seriously ill COVID-19 patients. In nearly 50% of COVID-19 patients, the value of D-dimer was significantly enhancing. Recent literature indicated that COVID-19 patients were at higher risk of developing disseminated intravascular coagulation. Pro-inflammatory cytokines and chemokines are some of the factors leading to these conditions. The majority of COVID-19 patients showed a higher profile of pro-inflammatory cytokines and chemokines in severe clinical conditions. Tumor necrosis factor-α (TNF-α) and interleukins (ILs) elevated in COVID-19 infected patients. TNF-α, IL-6, and IL-1 are major cytokines vital for the inhibition of intrinsic anticoagulant pathways. COVID-19 becomes a higher complication with a significant effect on blood cell production and hemostasis cascades. Deep vein thrombosis and arterial thrombosis are common complications. Changes in hematological parameters are also frequently observed in COVID-19 patients. Especially, thrombocytopenia is an indicator for poor prognosis of the disease and is highly expected and aggravates the likelihood of death of SARS-CoV-2 infected individuals. Thrombopoiesis reduction in COVID-19 patients might be due to viral abuse of the bone marrow/the viral load may affect thrombopoietin production and function. In other ways, immune-inflammation-mediated destruction and increased consumption of platelets are also the possible proposed mechanisms for thrombocytopenia. Therefore, the counting of platelet cells is an easily accessible biomarker for disease monitoring. All SARS-CoV-2 infected patients should be admitted and identifying potential higher-risk patients. It is also obligatory to provide appropriate treatments with intensive care and strict follow-up. In addition, considerations of chronic diseases are essential for better prognosis and recovery. The current review discusses coagulopathy among SARS-CoV-2 infected individuals and its complication for the management of the disease.

A "Catastrophic" Heparin-Induced Thrombocytopenia

Background

Heparin-induced thrombocytopenia (HIT) is a transient, antibody-mediated thrombocytopenia syndrome that usually follows exposure to unfractioned heparin (UFH) or low-molecular-weight heparin (LMWH). In contrast to other pathological conditions which lead to thrombocytopenia and bleeding complications, HIT results in a paradoxical prothrombotic state. It is caused by antibodies directed to complexes containing UFH or LMWH and a self-platelet protein: the platelet factor 4 (PF4). The heparin-PF4 immune complex leads to activation of platelets, monocytes, and endothelial cells which release procoagulant proteins and tissue factor with subsequent blood coagulation activation. Case Report. We describe the case of a woman undergone to knee replacement and affected by urosepsis who developed a HIT after exposure to enoxaparin. The thrombotic burden was very impressive involving the arterial and venous cerebral vessel and the venous pulmonary, hepatic, and inferior legs vascular beds. The patient was successfully treated with fondaparinux without recurrent thrombosis or bleeding. The clinical scenario could be named “catastrophic HIT” like the catastrophic antiphospholipid syndrome since they have a similar pathogenetic mechanism involving both platelets and monocytes procoagulant activities and a similar clinical manifestation with a life-threatening multiple arterial and/or venous thromboses.

Conclusion

Patients presenting with HIT could show a very impressive thrombotic burden resembling to that of the catastrophic antiphospholipid syndrome. A careful differential diagnosis should be made towards other pathological conditions which lead to thrombocytopenia to avoid an unnecessary and potentially harmful platelet transfusion. Although fondaparinux is off-label, its use in patients with HIT is simple and seems to be effective.

Crosstalk between platelets and the complement system in immune protection and disease

Platelets have a central function in repairing vascular damage and stopping acute blood loss. They are equally central to thrombus formation in cardiovascular diseases such as myocardial infarction and ischaemic stroke. Beyond these classical prothrombotic diseases, immune mediated pathologies such as haemolytic uraemic syndrome (HUS) or paroxysmal nocturnal haemoglobinuria (PNH) also feature an increased tendency to form thrombi in various tissues. It has become increasingly clear that the complement system, part of the innate immune system, has an important role in the pathophysiology of these diseases. Not only does complement influence prothrombotic disease, it is equally involved in idiopathic thrombocytopenic purpura (ITP), an autoimmune disease characterised by thrombocytopenia. Thus, there are complex interrelationships between the haemostatic and immune systems, and platelets and complement in particular. Not only does complement influence platelet diseases such as ITP, HUS and PNH, it also mediates interaction between microbes and platelets during systemic infection, influencing the course of infection and development of protective immunity. This review aims to provide an integrative overview of the mechanisms underlying the interactions between complement and platelets in health and disease.

The use of intravesicular alteplase for thrombolysis in a dog with urinary bladder thrombi

OBJECTIVE

To describe the use of alteplase for intravesicular thrombolysis in a dog after development of urinary tract obstruction from a blood clot in the urinary bladder.

CASE SUMMARY

A 5.8 kg, 6.5-year-old female neutered Bichon Frise was presented for signs of acute hematuria. A complete blood count (CBC) revealed marked thrombocytopenia and leukopenia, and nonregenerative anemia. Bone marrow aspirate cytology revealed mild hypercellularity, mild megakaryocytic hyperplasia, mildly left-shifted erythroid maturation, and moderately left-shifted myeloid maturation, suggesting ongoing recovery from an acute bone marrow insult. Thrombocytopenia and hematuria resolved concurrently; however, stranguria and oliguria developed acutely. Ultrasonography identified two large presumed thrombi within the urinary bladder. A urinary catheter was placed and 4 doses of 0.5 mg of alteplase diluted in 10 mL of 0.9% sodium chloride were instilled into the bladder with a 4-hour dwell time at 12-hour intervals. Prothombin and activated partial thromboplastin times were monitored during therapy and remained within normal limits. One thrombus was successfully dissolved after 48 hours of therapy and the remaining thrombus was reduced in size and was voided upon removal of the urinary catheter.

NEW OR UNIQUE INFORMATION PROVIDED

This report describes the use of alteplase in a dog for thrombolysis of intravesicular thrombi. In patients that develop intravesicular thrombi, intravesical instillation of alteplase can be considered as a method for dissolution of these thrombi.

A Seeming Paradox: Ischemic Stroke in the Context of Idiopathic Thrombocytopenic Purpura

Nowadays, we have a relatively sophisticated standard approach to a patient with acute ischemic stroke, including the sequence of diagnostic methods and treatment modalities. In practice, however, we are occasionally confronted with a patient whose medical history or comorbidities force us to make a decision without the support of guidelines. One such situation is the occurrence of acute ischemic stroke in a patient with known idiopathic thrombocytopenic purpura, where a tendency to use thrombolysis, anticoagulants, or antiplatelet agents collides with the fear of life-threatening bleeding. In this review, we try to outline current understanding of the pathophysiology of "paradoxical" ischemic events in this illness characterized by thrombocytopenia and to summarize clinical experience from case reports dealing with this topic, which could help us to rely on more than individual opinion seen through a purely "neurological" or "hematological" prism.

Sequential occurrence of thrombotic thrombocytopenic purpura, essential thrombocythemia, and idiopathic thrombocytopenic purpura in a 42-year-old African-American woman: a case report and review of the literature

Introduction

Thrombotic thrombocytopenic purpura and idiopathic thrombocytopenic purpura are two well recognized syndromes that are characterized by low platelet counts. In contrast, essential thrombocythemia is a myeloproliferative disease characterized by abnormally high platelet numbers.

The coexistence of thrombotic thrombocytopenic purpura and idiopathic thrombocytopenic purpura in a single patient has been reported in the literature on a few occasions. However, having essential thrombocythemia complicating the picture has never been reported before.

Case presentation

We present a case where thrombotic thrombocytopenic purpura, essential thrombocythemia, and idiopathic thrombocytopenic purpura were diagnosed in a 42-year-old African-American woman in the space of a few years; we are reporting this case with the aim of drawing attention to this undocumented occurrence, which remains under investigation.

Conclusions

As the three conditions have different natural histories and require different treatment modalities, it is important to recognize that these diseases may be seen sequentially. This case emphasizes the importance of reviewing peripheral blood smears for evaluation of thrombocytopenia and bone marrow aspirations for diagnosis of thrombocythemia in order to reach an accurate diagnosis and tailor therapy accordingly. Moreover, this case demonstrates the variability and complexity of platelet disorders. This occurrence of three different types of platelet disorders in one patient remains a pure observation on our part; regardless, this does raise the possibility of a common underlying, as yet undiscovered, pathophysiology that could explain the phenomenon.

The role of complement in the antiphospholipid syndrome: a novel mechanism for pregnancy morbidity

OBJECTIVES

Despite the experimental research data on antiphospholipid syndrome (APS), the pathogenesis of thrombosis and fetal loss remains unknown. The objective of this study was to analyze the major advances in the field of complement activation as a possible thrombosis mechanism in the APS.

METHODS

The authors conducted a systemic analysis of the English literature and summarized both animal and human data that indicate the inappropriate complement activation as a mechanism causing thrombosis in the APS.

RESULTS

The important role of complement activation in the pathogenesis of fetal loss was established using mice deficient in a complement regulatory protein. Further studies have shown that the infusion of human IgG antiphospholipid antibodies (aPL) induced fetal loss in pregnant mice, an effect that was abrogated by the concurrent administration of a C3 convertase inhibitor. Further studies suggested that C5a and neutrophils were the key components responsible for fetal injury. Moreover, use of F(ab)'2 fragments of aPL suggested the complement activation occurred mainly via the classical pathway. Other studies using models of induced thrombosis suggested that antibodies against β2GPI required the presence of terminal complement components to induce thrombus formation, and mice deficient in C3 or C5 were found to be resistant to aPL-induced thrombosis. Based on the aforementioned findings, it has been suggested that heparin prevents fetal loss in patients with APS by inhibiting complement activation rather than by its anticoagulant effect.

CONCLUSIONS

The studies on complement are significant because they shift the focus of research in APS from thrombosis to inflammation. However, as human data are limited, more clinical research is necessary before the above findings translate in changes in the management of APS.

Hepatitis C virus infection among patients with chronic immune thrombocytopenic purpura in northern India

BACKGROUND

Hepatitis C virus (HCV) has been reported to be associated with the occurrence of autoimmune disorders, including immune thrombocytopenic purpura (ITP). This has suggested that HCV could be responsible for thrombocytopenia in these patients. This study was performed to estimate the frequency of HCV infection in patients of chronic ITP (cITP), and to find the frequency of thrombocytopenia in chronic HCV infection.

MATERIALS

A total of 150 subjects were included in the study. Fifty consecutive adult patients with cITP (< 6 months' duration) and 50 age-matched patients with chronic HCV were included for comparison of platelet counts in two groups. Fifty age-matched healthy subjects were also included in the control group. All patients' sera were tested for the presence or absence of HCV-RNA. Anti-HCV antibodies were tested in patients as well as in controls. Complete blood count and examination of peripheral blood smear were done followed by bone-marrow aspiration to confirm the diagnosis of ITP.

RESULTS

Three patients (6%) were tested positive for anti-HCV antibodies while no subject was positive in control group (P=0.24). The prevalence of severe thrombocytopenia (platelet counts <50,000/mL) was significantly higher in ITP patients compared with that in chronic HCV patients (P=0.0001). Thrombocytopenia occurred more frequently in patient with moderate to severe than mild stage of fibrosis (P=0.001).

CONCLUSION

In conclusion, thrombocytopenia in ITP patients was not associated with HCV infection. The prevalence of thrombocytopenia was more common and more severe in ITP patients when compared with that in patients with chronic HCV. Thrombocytopenia in chronic HCV patients was related to the stage of fibrosis and to the duration of HCV infection.

Immune thrombocytopenia in patients with connective tissue disorders and the antiphospholipid antibody syndrome

It has been theorized that immune thrombocytopenia (ITP) is a syndrome characterized by various defects in immune regulation, resulting in a common phenotype, decreased blood platelets, and symptoms of mucocutaneous bleeding. Most often, successful treatment of the underlying connective tissue disorder with corticosteroids or other disease-modifying agents can simultaneously improve concurrent thrombocytopenia. The best evidence to date would support the targeting of treatment to the connective tissue disorder, expecting a simultaneous improvement in the platelet count. Due to the frequent relapses associated with many of the connective tissue disorders and the frequent use of immunosuppressant agents, splenectomy should be undertaken only in highly refractory patients. Differentiating the varying immunopathic etiologies that contribute to development of connective tissue disorders may lead to a better understanding of the mechanisms of thrombocytopenia in a subset of these patients. The use of target therapies to treat connective tissue disorders has the potential of reducing the risk of the development of ITP or, conversely, inducing the development of immune thrombocytopenia.

Massive cerebrovascular infarct due to the catastrophic antiphospholipid syndrome in a patient with idiopathic thrombocytopenic purpura

Catastrophic antiphospholipid syndrome (APS) is caused by thrombotic vascular occlusions that affect both small and large vessels, producing ischemia in the affected organs as well as a systemic inflammatory response syndrome (SIRS). We report a case of a patient with idiopathic thrombocytopenic purpura (ITP) who developed massive cerebral ischemia due to this entity. Prompt and aggressive treatment may prevent and actually resolve lethal complications caused by this devastating syndrome.

Atypical haemolytic uremic syndrome complicated by microangiopathic antiphospholipid-associated syndrome

A 4-year-old boy with an atypical course of haemolytic uremic syndrome (HUS), who developed microangiopathic antiphospholipid-associated syndrome (MAPS) with signs of multiple organ failure during the course of his disease, is reported. Early and aggressive treatment with intravenous gammaglobulin, pulse methylprednisolone and plasmapheresis resulted in an excellent clinical recovery. Our patient showed a concomitant presence of multiple factors that could precipitate atypical HUS, including positive antiphospholipid antibodies, decreased level of factor H and positive anti-ADAMTS-13 antibodies. We suggest that, along with infections, autoimmune conditions or defined genetic abnormalities of complement regulatory genes, MAPS should be considered among the pathogenic mechanisms in patients with atypical HUS.

The physiopathology of the catastrophic antiphospholipid (Asherson's) syndrome: compelling evidence

Catastrophic antiphospholipid (Asherson's) syndrome (cAPS) was described in the past as a severe variant of the antiphospholipid syndrome (APS). Currently growing evidence suggests it is a unique condition. This statement is based on several clinical and physiopathological features that although not well understood define cAPS by itself. The remarkable features of cAPS are the presence of antiphospholipid antibodies (aPLAs) and microthromboses. Additional physiopathological features are the presence of anemia and thrombocytopenia, which are also often described in similar autoimmune conditions. A strong association with concomitant infection is thought to act as the main trigger of microthromboses in cAPS. Several theories have been proposed to explain these physiopathological features. Some of them suggest the possibility of molecular mimicry between components of infectious microorganisms and natural anticoagulants, which might be involved in the production of cross-reacting aPLAs in cAPS. Some genetic risk factors have also been suggested to be implicated in the onset of cAPS, however they have not been defined yet. Herein, we review the remarkable physiopathological features commonly described in cAPS hitherto. We concluded that although they are not completely understood, it is possible to differentiate them from similar conditions. Nevertheless further studies on these physiopathological mechanisms of the disease are needed.

Infections and autoimmunity: a panorama

For more than 2,000 years, it was thought that malignant spirits caused diseases. By the end of nineteenth century, these beliefs were displaced by more modern concepts of disease, namely, the formulation of the “germ theory,” which asserted that bacteria or other microorganisms caused disease. With the emergence of chronic degenerative and of autoimmune diseases in the last century, the causative role of microorganisms has been intensely debated; however, no clear explanatory models have been achieved. In this review, we examine the current available literature regarding the relationships between infections and 16 autoimmune diseases. We critically analyzed clinical, serological, and molecular associations, and reviewed experimental models of induction of and, alternatively, protection from autoimmune diseases by infection. After reviewing several studies and reports, a clinical and experimental pattern emerges: Chronic and multiple infections with viruses, such as Epstein–Barr virus and cytomegalovirus, and bacteria, such as H. pylori, may, in susceptible individuals, play a role in the evolvement of autoimmune diseases. As the vast majority of infections pertain to our resident microbiota and endogenous retroviruses and healthy carriage of infections is the rule, we propose to focus on understanding the mechanisms of this healthy carrier state and what changes its configurations to infectious syndromes, to the restoration of health, or to the sustaining of illness into a chronic state and/or autoimmune disease. It seems that in the development of this healthy carriage state, the infection or colonization in early stages of ontogenesis with key microorganisms, also called ‘old friends’ (lactobacilli, bifidobacteria among others), are important for the healthy living and for the protection from infectious and autoimmune syndromes.

Antiphospholipids antibodies in a 12-month-old presenting with idiopathic thrombocytopenic purpura

A 12-month-old Caucasian female with a history of recurrent ear infections presented to the emergency room with petechiae, severe thrombocytopenia (4000/microL), and abnormally prolonged activated partial thromboplastin time. Further autoantibody investigation detected antinuclear antibodies, anti-double-stranded DNA, and antiphospholipid antibodies. Platelet count, in response to intravenous immunoglobulin infusion, increased to more than 100 x 10(3) plt/microL. At 6-month follow-up, no positive autoantibodies were detected.

Spontaneous superior sagittal sinus thrombosis secondary to type II heparin-induced thrombocytopenia presenting as an acute subarachnoid hemorrhage

Cerebral sinus thrombosis is a rare cause of spontaneous subarachnoid hemorrhage. The development of cerebral sinus thrombosis as a complication of heparin-induced thrombocytopenia is even rarer. In this paper, we present a 59-year-old patient admitted to our service with cerebral sinus thrombosis secondary to type II heparin-induced thrombocytopenia. We also review the literature in regard to the incidence, pathophysiology and management of this rare clinicopathological entity.