Catastrophic antiphospholipid syndrome. Clinical and laboratory features of 50 patients

Hematological features and alternate diagnoses in critically ill thrombotic antiphospholipid syndrome patients

OBJECTIVES

Severe thrombotic antiphospholipid syndrome (APS) frequently affects the kidney, heart, and central nervous system. The precise frequency, clinical picture, differential diagnoses, and outcome of APS-related hematological involvement are lacking, especially in patients requiring ICU admission. This study aimed to describe the hematological manifestations associated with critically ill thrombotic APS patients and catastrophic antiphospholipid syndrome.

METHODS

This French, national, multicenter, retrospective study, conducted, from January 2000 to September 2018, included all APS patients admitted to 24 participating centers' ICUs with any new thrombotic manifestation. The prevalence of hematological manifestations and their associated outcomes were studied.

RESULTS

One hundred and thirty-four patients, female 72%, median [IQR] age 45 [34-56] years, with 152 episodes were included. Anemia was present in 95% of episodes and thrombocytopenia in 93%. The lowest values for hemoglobin and platelets were 7.1 [6.3-8.8] g/dL and 38 [21-60] g/L, respectively. The lowest platelet count below 20 g/L was significantly associated with a higher in-ICU mortality rate (50%, p < 0.0001). A thrombotic microangiopathy syndrome (TMA) syndrome was seen in 16 patients (12%) and was associated with higher in-hospital mortality (p = 0.05). Median ADAMTS-13 levels were 44% [27-74]. Anti-ADAMTS13 antibodies were tested in 11 patients and found negative in all. A suspicion of heparin-induced thrombocytopenia (HIT) was raised in 66 patients but only four patients were classified as definite HIT. Disseminated intravascular coagulation (DIC) was seen in 51% of patients.

CONCLUSION

Thrombocytopenia is very frequent in severe APS patients and may be related to TMA, HIT, or DIC. Deciphering the mechanisms of thrombocytopenia is decisive in CAPS patients. Key Points • Thrombocytopenia is the hallmark laboratory finding in CAPS. • A complete thrombotic microangiopathy pattern is infrequent in CAPS patients. • Alternate diagnoses of CAPS, especially heparin-induced thrombocytopenia, need to be adequately investigated.

Catastrophic Thrombosis: A Narrative Review

Catastrophic thrombosis is a severe condition characterized by a hypercoagulable tendency, leading to multiple thromboembolic events in different blood vessels, usually within a short timeframe. Several conditions have been associated with the development of catastrophic thrombosis, including the catastrophic antiphospholipid syndrome, thrombotic anti-platelet factor 4 immune disorders, thrombotic microangiopathies, cancers, the hyper-eosinophilic syndrome, pregnancy, infections, trauma, and drugs. Thrombotic storm represents a medical emergency whose management represents a serious challenge for physicians. Besides the prompt start of anticoagulation, a patient's prognosis depends on early recognition and possible treatment of the underlying condition. In this narrative review, we summarize the main characteristics of catastrophic thrombosis, analyzing the various conditions triggering such life-threatening complication. Finally, an algorithm with the diagnostic workup and the initial management of patients with catastrophic thrombosis is presented.

Antiphospholipid Patients Admitted in the Intensive Care Unit: What Must The Rheumatologist Know?

PURPOSE OF THE REVIEW

Antiphospholipid syndrome (APS) is a rare systemic autoimmune disorder that can escalate into a 'thrombotic storm' called the catastrophic antiphospholipid syndrome (CAPS), frequently requiring ICU admission for multiple organ failure. This review aims to offer insight and recent evidence on critically-ill APS patients.

RECENT FINDINGS

The CAPS classification criteria define this condition as the involvement of at least three organs/systems/tissues within less than a week, caused by small vessel thrombosis, in patients with elevated antiphospholipid antibodies levels. These criteria do not encompass the full spectrum of critically-ill thrombotic APS patients and they need to be cautiously used for the bedside diagnosis of CAPS. Thrombocytopenia is the laboratory hallmark of CAPS, sometimes dropping below 20G/L, but a complete thrombotic microangiopathy pattern is infrequent. Anticoagulation is the pivotal treatment for APS and CAPS, associated with improved outcome. Triple therapy - the combination of anticoagulation, high-dose corticosteroids, and either plasma exchange or intravenous immunoglobulins - remains the standard treatment for CAPS patients. Eculizumab, an anti-C5 monoclonal antibody, may be useful in refractory patients. Despite significant progress, CAPS mortality rate remains high. Its diagnosis and management are complex, requiring a close multidisciplinary cross talk between APS specialists and intensivists.

Extensive Thrombosis in Catastrophic Antiphospholipid Syndrome in a Newly Diagnosed Systemic Lupus Erythematosus: A Case Report

In this case report, we present the development of catastrophic antiphospholipid syndrome (CAPS), a rare and potentially fatal consequence of systemic lupus erythematosus (SLE), in a 33-year-old Micronesian woman. CAPS is characterized by extensive arterial thrombosis and multiorgan failure. The patient first showed signs of neuropsychiatric symptoms, brain infarctions on imaging, and severe hypoxic respiratory failure brought into the hospital by diffuse alveolar hemorrhage (DAH) along with lupus nephritis (LN). Blood urea nitrogen (BUN) and creatinine (Cr) were progressively elevated to 102/4.1 mg/dL, respectively. A urinalysis revealed microscopic hematuria and proteinuria with a urine protein/creatinine ratio of 6052 mg/g. She was also found to have had microangiopathic hemolytic anemia (MAHA) and severe venous thrombosis, both of which were indicative of CAPS. An aggressive approach, including immunosuppressive medication, therapeutic plasma exchange, and anticoagulation, had positive results, including renal recovery and the cessation of thrombotic episodes. This instance highlights how crucial it is to identify CAPS patients early and take appropriate action to improve patient outcomes for this difficult and sometimes deadly disorder.

Diagnosis and Management of Catastrophic Antiphospholipid Syndrome and the Potential Impact of the 2023 ACR/EULAR Antiphospholipid Syndrome Classification Criteria

Catastrophic antiphospholipid syndrome (CAPS) is a rare and life-threatening condition characterized by the persistence of antiphospholipid antibodies and occurrence of multiple vascular occlusive events. CAPS currently remains a diagnostic challenge and requires urgent treatment. The diagnosis of CAPS is made difficult by classification criteria used as diagnostic criteria in clinical practice, knowledge derived from retrospective data and case reports, confounding clinical and biological features, and its rapid onset and mortality. The absence of prospective studies of CAPS limits the strength of evidence for guideline treatment protocols. This comprehensive review summarizes the current understanding of the disease, and discusses how the 2023 ACR/EULAR Antiphospholipid Syndrome Classification Criteria impact the definition and therapeutic management of CAPS, which is considered the most severe form of APS. The correct integration of 2023 ACR/EULAR APS classification criteria is poised to facilitate CAPS diagnosis, particularly in critical situations, offering a promising avenue for improved outcomes.

Pulmonary involvement in catastrophic antiphospholipid syndrome: A descriptive analysis from the "CAPS Registry"

OBJECTIVES

To describe the pulmonary involvement in patients with catastrophic antiphospholipid syndrome (CAPS), focusing on its relationship with extrapulmonary involvement, laboratory, radiological, and pathological findings.

METHODS

This retrospective cross-sectional study includes all patients grouped in the "CAPS Registry". All cases were reviewed, and those with pulmonary thromboembolism (PE) and/or diffuse alveolar hemorrhage (DAH) were selected. Data on pulmonary and extrapulmonary clinical presentation, radiologic patterns, laboratory findings, associated autoimmune diseases, treatments, and outcomes were analyzed. Frequency distribution and measures of central tendency were used to describe the cohort. Comparison between groups regarding qualitative variables was undertaken by chi-square or Fisher exact test, while T-test for independent variables was used to compare groups regarding continuous variables. IBM-SPSS v.22 was used for data analysis.

RESULTS

PE was reported in 129 (48.6 %) episodes, DAH in 75 (28.3 %) episodes, and overlap (DAH plus PE) in 7 (2.6 %) episodes. Bronchoalveolar lavage (BAL) was performed in 35 (4.9 %) CAPS episodes, and lung pathology samples were obtained in 84 (10.5 %) episodes (including autopsies). A significant relationship was observed between DAH and laboratory features of thrombotic microangiopathy (TMA). A meaningful relationship was also found between triple antiphospholipid antibody positivity and pathological TMA (26.5 %) as well as hypocomplementemia and DAH (24 %).

CONCLUSIONS

Pulmonary involvement may include both TMA and non-thrombotic inflammation, which can be differentiated into three patterns: PE, DAH with systemic TMA with hypocomplementemia or DAH without systemic TMA with/without hypocomplementemia.

Complement biomarkers in the antiphospholipid syndrome - Approaches to quantification and implications for clinical management

Complement is a major driver of antiphospholipid syndrome (APS) and a promising therapeutic target in refractory and catastrophic APS. Complement testing in APS is largely limited to research settings, and reliable, rapid-turnaround biomarkers are needed to predict those at risk for adverse clinical outcomes and most likely to benefit from complement inhibition. We review complement biomarkers and their association with thrombosis and obstetric outcomes, including: (i) complement proteins and activation fragments in the fluid phase; (ii) assays that evaluate complement on cell membranes (e.g. in vivo cell-bound complement fragments, hemolytic assays, and ex vivo 'functional' cell-based assays, and (iii) sequencing of complement genes. Current studies highlight the inconsistencies in testing both between studies and various aPL/APS subgroups, suggesting that either cell-based testing or multiplex panels employing a combination of biomarkers simultaneously may be most clinically relevant. Standardization of complement assays is needed to ensure reproducibility and establish clinically relevant applications.

mTOR-dependent loss of PON1 secretion and antiphospholipid autoantibody production underlie autoimmunity-mediated cirrhosis in transaldolase deficiency

Transaldolase deficiency predisposes to chronic liver disease progressing from cirrhosis to hepatocellular carcinoma (HCC). Transition from cirrhosis to hepatocarcinogenesis depends on mitochondrial oxidative stress, as controlled by cytosolic aldose metabolism through the pentose phosphate pathway (PPP). Progression to HCC is critically dependent on NADPH depletion and polyol buildup by aldose reductase (AR), while this enzyme protects from carbon trapping in the PPP and growth restriction in TAL deficiency. Although AR inactivation blocked susceptibility to hepatocarcinogenesis, it enhanced growth restriction, carbon trapping in the non-oxidative branch of the PPP and failed to reverse the depletion of glucose 6-phosphate (G6P) and liver cirrhosis. Here, we show that inactivation of the TAL-AR axis results in metabolic stress characterized by reduced mitophagy, enhanced overall autophagy, activation of the mechanistic target of rapamycin (mTOR), diminished glycosylation and secretion of paraoxonase 1 (PON1), production of antiphospholipid autoantibodies (aPL), loss of CD161+ NK cells, and expansion of CD38+ Ito cells, which are responsive to treatment with rapamycin in vivo. The present study thus identifies glycosylation and secretion of PON1 and aPL production as mTOR-dependent regulatory checkpoints of autoimmunity underlying liver cirrhosis in TAL deficiency.

Clinical features, risk factors, and outcomes of diffuse alveolar hemorrhage in antiphospholipid syndrome: A mixed-method approach combining a multicenter cohort with a systematic literature review

BACKGROUND

Antiphospholipid syndrome (APS) is a systemic autoimmune disease clinically associated with thrombotic and obstetric events. Additional manifestations have been associated with APS, like diffuse alveolar hemorrhage (DAH). We aimed to summarize all the evidence available to describe the presenting clinical features, their prognostic factors, and short- and long-term outcomes.

METHODS

We performed a mixed-method approach combining a multicenter cohort with a systematic literature review (SLR) of patients with incident APS-associated DAH. We described their clinical features, treatments, prognostic factors, and outcomes (relapse, mortality, and requirement of mechanical ventilation [MV]). Kaplan-Meier methods were used to estimate relapse and mortality rates, and Cox and logistic regression models were used to assess the factors associated as appropriate.

RESULTS

We included 219 patients with incident APS-associated DAH (61 from Mayo Clinic and 158 from SLR). The median age was 39.5 years, 51% were female, 29% had systemic lupus erythematosus, and 34% presented with catastrophic APS (CAPS). 74% of patients had a history of thrombotic events, and 26% of women had a history of pregnancy morbidity; half of the patients had a history of thrombocytopenia, and a third had valvulopathy. Before DAH, 55% of the patients were anticoagulated. At DAH onset, 65% of patients presented hemoptysis. The relapse rate was 47% at six months and 52% at one year. Triple positivity (HR 4.22, 95% CI 1.14-15.59) was associated with relapse at six months. The estimated mortality at one and five years was 30.3% and 45.8%. Factors associated with mortality were severe thrombocytopenia (< 50 K/μL) (HR 3.10, 95% CI 1.39-6.92), valve vegetations (HR 3.22, 95% CI 1.14-9.07), CAPS (HR 3.80, 95% CI 1.84-7.87), and requirement of MV (HR 2.22, 95% CI 1.03-4.80). Forty-two percent of patients required MV on the incident DAH episode. Patients presenting with severe thrombocytopenia (OR 6.42, 95% CI 1.77-23.30) or CAPS (OR 4.30, 95% CI 1.65-11.16) were more likely to require MV.

CONCLUSION

APS-associated DAH is associated with high morbidity and mortality, particularly when presenting with triple positivity, thrombocytopenia, valvular involvement, and CAPS.

Primary adrenal insufficiency due to bilateral adrenal hemorrhage-adrenal infarction in a patient with systemic lupus erythematosus and antiphospholipid syndrome: case presentation and review of the literature

Primary adrenal insufficiency (PAI) is a rare disease which represents the end stage of a destructive process involving the adrenal cortex. Occasionally it may be caused by bilateral adrenal hemorrhagic infarction in patients with antiphospholipid syndrome (APS). We herein report the challenging case of a 30-year-old female patient with systemic lupus erythematosus (SLE) and secondary APS who was admitted to the emergency department (ED) due to fever, lethargy, and syncopal episodes. Hyponatremia, hyperkalemia, hyperpigmentation, shock, altered mental status, and clinical response to glucocorticoid administration were features highly suggestive of an acute adrenal crisis. The patient's clinical status required admission to the intensive care unit (ICU), where steroid replacement, anticoagulation, and supportive therapy were provided, with a good outcome. Imaging demonstrated bilateral adrenal enlargement attributed to recent adrenal hemorrhage. This case highlights the fact that bilateral adrenal vein thrombosis and subsequent hemorrhage can be part of the thromboembolic complications seen in both primary and secondary APS and which, if misdiagnosed, may lead to a life-threatening adrenal crisis. High clinical suspicion is required for its prompt diagnosis and management. A literature search of past clinical cases with adrenal insufficiency (AI) in the setting of APS and SLE was conducted using major electronic databases. Our aim was to retrieve information about the pathophysiology, diagnosis, and management of similar conditions.

French National Diagnostic and Care Protocol for antiphospholipid syndrome in adults and children

Antiphospholipid syndrome (APS) is a chronic autoimmune disease involving vascular thrombosis and/or obstetric morbidity and persistent antibodies to phospholipids or certain phospholipid-associated proteins. It is a rare condition in adults and even rarer in children. The diagnosis of APS can be facilitated by the use of classification criteria based on a combination of clinical and biological features. APS may be rapidly progressive with multiple, often synchronous thromboses, resulting in life-threatening multiple organ failure. This form is known as "catastrophic antiphospholipid syndrome" (CAPS). It may be primary or associated with systemic lupus erythematosus (associated APS) and in very rare cases with other systemic autoimmune diseases. General practitioners and paediatricians may encounter APS in patients with one or more vascular thromboses. Because APS is so rare and difficult to diagnosis (risk of overdiagnosis) any suspected case should be confirmed rapidly and sometimes urgently by an APS specialist. First-line treatment of thrombotic events in APS includes heparin followed by long-term anticoagulation with a VKA, usually warfarin. Except in the specific case of stroke, anticoagulants should be started as early as possible. Any temporary discontinuation of anticoagulants is associated with a high risk of thrombosis in APS. A reference/competence centre specialised in autoimmune diseases must be urgently consulted for the therapeutic management of CAPS.

Antiphospholipid Syndrome: State of the Art of Clinical Management

Antiphospholipid syndrome (APS) is a systemic autoimmune disorder clinically characterized by recurrent arterial and venous thrombosis and/or pregnancy morbidity in the presence of antiphospholipid antibodies. Currently, treatment is mainly focused on anticoagulation, but therapies targeting mechanisms involved in APS autoimmune pathogenesis could play an important role in specific settings. An evidence-based therapeutic approach is limited by the broad clinical spectrum of the syndrome and the nature of a "rare disease" that makes it difficult to carry out well-designed prospective studies. Vitamin K antagonists (AVK), notably warfarin, are the standard treatment for preventing recurrent venous thrombosis and perhaps also arterial thrombosis. Direct oral anticoagulants (DOACs) are not recommended at least in patients with triple positivity APS. Treatment options for the prevention of pregnancy complications in obstetric APS, as combined use of aspirin and heparin, low-dose prednisolone, hydroxychloroquine, intravenous immunoglobulin (IVIG), may improve pregnancy outcome. The catastrophic antiphospholipid syndrome (CAPS) is the most severe form of APS with acute multiple organ involvement and small vessel thrombosis. Glucocorticoids, heparin, plasma exchange or IVIG, rituximab, or eculizumab must be added to concurrent treatment of precipitating factors (e.g. infections) as rescue therapies. Finally, it has been observed that SARS COV2 infection may produce vascular complications mimicking the clinical and pathophysiological features of APS and particularly of CAPS. From this point of view, attention has been focused on the "protective" role of anticoagulant therapy in preventing thrombotic complication when these clinical conditions coexist.

Rheumatic diseases associated with alveolar hemorrhage: analysis of the national inpatient sample

OBJECTIVE

Diffuse alveolar hemorrhage (DAH) is a severe pulmonary complication of numerous diseases, including rheumatic conditions. We have conducted an observational study using inpatient data from the National Inpatient Sample to study the relationship of DAH with rheumatic conditions along with their descriptive characteristics.

METHODS

An observational study was conducted on hospitalizations in 2016-2018 with a principal diagnosis of DAH from the United States National Inpatient Sample database. A multivariate logistic regression analysis was performed to calculate adjusted odds ratios (OR_adj) for risk factors of DAH.

RESULTS

A total of 5420 DAH hospitalizations were identified among 90 million hospitalizations. Mortality in this group was found to be 24.3%. Majority of patients admitted with DAH were white and male, with a mean age of 61.8 years and a mean LOS of 10.6 days. Multivariate analysis showed that multiple rheumatic diseases were associated with DAH, including anti-neutrophil cytoplasmic antibody-associated vasculitis (AAV) (OR_adj 72.56) (95% C.I. 50.607-104.043), antiphospholipid antibody syndrome (APLS) (OR_adj 6.51) (95% C.I. 3.734-11.366), eosinophilic granulomatosis with polyangiitis (EGPA) (OR_adj 7.13) (95% C.I. 1.886-26.926), Goodpasture's (OR_adj 30.58) (95% C.I. 16.360-57.176), rheumatoid arthritis (RA) (OR_adj 1.60) (95% C.I. 1.158-2.212), sarcoidosis (OR_adj 3.99) (95% C.I. 2.300-6.926), and systemic lupus (SLE) (OR_adj 5.82) (95% C.I. 3.993-8.481).

CONCLUSION

Although DAH is a relatively rare entity, it carries a very high mortality. Multiple rheumatic diseases were associated with DAH hospitalizations including AAV, APLS, EGPA, Goodpasture's, RA, sarcoidosis, and SLE. Key points • It is known that DAH carries a high morbidity and mortality based on prior literature. However, large datasets on the association of rheumatic diseases with DAH are lacking • This study identifies the descriptive characteristics of patients admitted to the hospital with DAH • This study also identifies the strength of association of rheumatic diseases with DAH.

Prevalence, characteristics and outcome of cardiac manifestations in critically-ill antiphospholipid syndrome patients

AIMS

Antiphospholipid syndrome (APS) is a rare autoimmune disease defined by thrombotic events occurring in patients with persistent antiphospholipid antibodies. Cardiac manifestations in critically-ill APS patients are poorly investigated. We conducted a study to assess the prevalence, the characteristics and the prognosis of cardiac manifestations in thrombotic APS patients admitted to intensive care unit (ICU).

METHODS AND RESULTS

A French, national, multicentre, retrospective study, conducted, from January 2000 to September 2018, including all APS patients admitted to 24 participating centres' ICUs with any new thrombotic (arterial, venous or microvascular) manifestation. Cardiac manifestations were defined as any new cardiac abnormalities relying on clinical examination, cardiac biomarkers, echocardiography, cardiac magnetic resonance (CMR) and coronarography. One hundred and thirty-six patients (female 72%) were included. Mean age at ICU admission was 46 ± 15years. Cardiac manifestations were present in 71 patients (53%). In patients with cardiac involvement, median left ventricular ejection fraction (LVEF) was 40% [28-55], troponin was elevated in 93% patients, coronary angiogram (n = 19, 27%) disclosing a coronary obstruction in 21%. CMR (n = 21) was abnormal in all cases, with late gadolinium enhancement in 62% of cases. Cardiac manifestations were associated with a non-significant increase of mortality (32% vs. 19%, p = 0.08). After 1-year follow-up, median LVEF was 57% [44-60] in patients with cardiac involvement.

CONCLUSION

Cardiac involvement is frequent in critically-ill thrombotic APS patients and may be associated to more severe outcome. Increased awareness on this rare cause of myocardial infarction with or without obstructive coronary artery is urgently needed.

The clinical significance of low complement levels in patients with catastrophic antiphospholipid syndrome: A descriptive analysis of 73 patients from the "Catastrophic antiphospholipid syndrome registry"

OBJECTIVES

To explore the prevalence and clinical significance of low complement levels in patients with catastrophic antiphospholipid syndrome (CAPS).

METHODS

We reviewed data from the "CAPS Registry" on C3 and/or C4 complement plasma protein levels during acute CAPS episodes. Patients were classified into those with low and normal complement levels. Data on clinical presentation, with special focus on thrombotic microangiopathy (TMA) features, diagnosis of systemic lupus erythematosus (SLE), and antiphospholipid antibody (aPL) profile were reviewed. The chi-square exact test was performed to evaluate differences between categorical data.

RESULTS

The "CAPS Registry" includes 566 patients with a total of 578 episodes of CAPS. Data on complement plasma protein levels was available in 73 episodes from the same number of patients. Low levels of C3 and/or C4 complement plasma proteins were detected in 42 (58%) CAPS episodes. Low complement levels were more common in SLE patients (55% SLE vs. 19% No SLE; p<0.001). The frequencies of clinical TMA (72% vs. 80%; p=0.4) or TMA syndrome (86% vs. 84%, p=0.9), frequency of triple aPL triple positivity (67% vs 33%; p=0.3), or the mortality (35% vs. 31%; p=0.7) were similar between low and normal complement groups.

CONCLUSION

In our study, low levels of C3 and C4 plasma proteins are detected in 58% episodes of CAPS, which were not associated with clinical presentation including TMA features, aPL triple positivity, or mortality.

Role of therapeutic apheresis in the treatment of pediatric kidney diseases

Therapeutic apheresis utilizes apheresis procedures in the treatment of a variety of conditions including kidney disease. Therapeutic plasma exchange (TPE) is the most common modality employed with the rationale of rapid reduction of a pathogenic substance distributed primarily in the intravascular compartment; however other techniques which adsorb such pathogenic substances or alter the immune profile have been utilized in diseases affecting native and transplanted kidneys. This article discusses the modalities and technical details of therapeutic apheresis and summarizes its role in individual diseases affecting the kidney. Complications related to pediatric apheresis procedures and specifically related to apheresis in kidney disease are also discussed. Though therapeutic apheresis modalities are employed frequently in children with kidney disease, most experiences are extrapolated from adult studies. International and national registries need to be established to elucidate the role of apheresis modalities in children with kidney disease.

Pathogenesis, Diagnosis and Management of Obstetric Antiphospholipid Syndrome: A Comprehensive Review

Antiphospholipid syndrome is an autoimmune disorder characterized by vascular thrombosis and/or pregnancy morbidity associated with persistent antiphospholipid antibody positivity. Cases fulfilling the Sydney criteria for obstetric morbidity with no previous thrombosis are known as obstetric antiphospholipid syndrome (OAPS). OAPS is the most identified cause of recurrent pregnancy loss and late-pregnancy morbidity related to placental injury. Cases with incomplete clinical or laboratory data are classified as obstetric morbidity APS (OMAPS) and non-criteria OAPS (NC-OAPS), respectively. Inflammatory and thrombotic mechanisms are involved in the pathophysiology of OAPS. Trophoblasts, endothelium, platelets and innate immune cells are key cellular players. Complement activation plays a crucial pathogenic role. Secondary placental thrombosis appears by clot formation in response to tissue factor activation. New risk assessment tools could improve the prediction of obstetric complication recurrences or thromboses. The standard-of-care treatment consists of low-dose aspirin and prophylactic low molecular weight heparin. In refractory cases, the addition of hydroxychloroquine, low-dose prednisone or IVIG improve pregnancy outcomes. Statins and eculizumab are currently being tested for treating selected OAPS women. Finally, we revisited recent insights and concerns about the pathophysiology, diagnosis and management of OAPS.

Case Report: An Unusual Case of Acute Lower Limb Ischemia as Precursor of the Asherson's Syndrome

Introduction: Asherson's Syndrome, also defined as Catastrophic Antiphospholipid Syndrome (CAPS), represents the most severe manifestation of Antiphospholipid Antibody Syndrome. Rarely, the first CAPS diagnosis is based on macro-thrombotic event as acute limb ischemia. Case Presentation: We present a case of a 65-year-old woman admitted with an acute lower limb arterial ischemia with a complete occlusion of all the three tibial vessels. Three endovascular recanalization procedures were performed contemporary to 48 h intraarterial thrombolysis administration. The patency of tibial arteries was restored with a near-complete absence of digital arteries and microvessel perfusion of the foot. In the following days, an aggressive foot gangrene was established, leading to a major lower-limb amputation. Due to the general clinical status worsening and aggressiveness of ischemic condition, further investigations were performed leading to the diagnosis of an aggressive Asherson's Syndrome that was also complicated by a severe heparin-induced thrombocytopenia. Medical management with a high dose of intravenous steroids and nine sessions of plasma exchange led to a clinical condition stabilization. Conclusion: In our case, the presence of a "sine causa" acute arterial occlusion of a large vessel represented the first manifestation of an aggressive form of Asherson's Syndrome that could represent a fatal disease. Due to the extreme variety of manifestations, early clinical suspicion, diagnosis, and multidisciplinary management are essential to limit the life-threatening consequences of patients.

Myocardial involvement in anti-phospholipid syndrome: Beyond acute myocardial infarction

Anti-phospholipid antibodies (aPL) are the serological biomarkers of anti-phospholipid syndrome (APS), an autoimmune disorder characterized by vascular events and/or pregnancy morbidity. APS is a unique condition as thrombosis might occur in arterial, venous or capillary circulations. The heart provides a frequent target for circulating aPL, leading to a wide variety of clinical manifestations. The most common cardiac presentation in APS, valvular involvement, acknowledges a dual etiology comprising both microthrombotic and inflammatory mechanisms. We describe the cases of 4 patients with primary APS who presented a clinically manifest myocardiopathy without epicardial macrovascular distribution. We propose that microthrombotic/inflammatory myocardiopathy might be an overlooked complication of high-risk APS. As extensively hereby reviewed, the literature provides support to this hypothesis in terms of anecdotal case-reports, in some cases with myocardial bioptic specimens. In aPL-positive subjects, microthrombotic/inflammatory myocardial involvement might also clinically manifest as dilated cardiomyopathy, a clinical entity characterized by ventricular dilation and reduced cardiac output. Furthermore, microthrombotic/inflammatory myocardial involvement might be subclinical, presenting as diastolic dysfunction. Currently, there is no single clinical or imaging finding to firmly confirm the diagnosis; an integrated approach including clinical history, clinical assessment, laboratory tests and cardiac magnetic resonance should be pursued in patients with suggestive clinical presentation.

A Difficult and Rare Case of Warfarin Refractory Antiphospholipid Syndrome Presenting With Catastrophic Antiphospholipid Syndrome Complicated by Gastrointestinal Bleeding

Antiphospholipid syndrome (APS) is managed with warfarin for secondary prophylaxis in patients who have had a thrombotic event in the past. Warfarin has been deemed superior to novel oral anticoagulants in preventing venous and arterial thrombosis in conjunction with aspirin. The catastrophic variant of APS (CAPS) is very rarely reported, especially in those who have been on a therapeutic dose of warfarin therapy. We present a rare case of CAPS in a patient with a history of APS who had been on a therapeutic dose of warfarin along with aspirin therapy. The patient is a 70-year-old male with APS diagnosed 30 years prior when he presented with a pulmonary embolism; aspirin was added to warfarin two years ago when he had a cerebrovascular accident (CVA). He presented to the hospital with acute onset right-sided weakness and aphasia, left lower extremity pain. He had ischemic CVA, acute deep vein thrombosis (DVT), acute renal failure with a creatinine of 2.8, anemia with hemoglobin of 3.8, gastrointestinal bleed (GIB) on EGD, with INR of 3.48 cardiolipin IgM of >140g/L. He was transfused packed red blood cells, fresh frozen plasma, and provided Vit K. Subsequently, he had a cardiac arrest and was intubated and placed on a mechanical ventilator. Given simultaneous multiorgan involvement, acute arterial and venous thrombosis, the patient was diagnosed with CAPS. The patient was started on high-dose dexamethasone, intravenous immunoglobulin (IVIG), and underwent plasma exchange with significant improvement in symptoms, laboratory parameters; and was extubated with near normalization of his speech and motor deficits. He was discharged on enoxaparin and prednisone with sustained clinical improvement two months following discharge. This patient was on the recommended treatment for APS. However, he had presented with a CAPS. This is the first reported case of warfarin refractory CAPS. This case highlights that there might be a subgroup of the population in whom warfarin is not an effective form of treatment modality for an unknown cause, and in fact, it could potently expose a patient to the adverse events related to warfarin therapy as it did in our patient who had significant GIB. This case also highlights the uncommon scenario of spontaneous CAPS with no inciting event as previously reported in the literature, such as infection, recent surgeries, or trauma.

Cardiovascular Considerations in Anesthetic Management for a Patient With Antiphospholipid Syndrome and Decreased Cardiac Function: A Case Study

This case report describes the prolonged general anesthetic management of a 41-year-old woman with antiphospholipid syndrome (APS), systemic lupus erythematosus, and previously undiagnosed decreased cardiac function who underwent planned partial resection of the left tongue, tracheostomy, neck dissection, and pedicled flap reconstruction. This was immediately followed by emergent surgery to salvage the flap, and 1 month later, revision of the soft tissue flap was performed. A preoperative echocardiogram was performed because of her various risk factors, which identified lateral wall hypokinesis and reduced left ventricular ejection fraction of 40%, despite no known cardiovascular disease. However, cardiology consult determined no additional treatment was needed before the surgery. Multiple antithrombotic strategies were used, including elastic stockings, intermittent pneumatic compression devises, and heparin bridging. During the general anesthetic, stroke volume variation (SVV) was used to assess cardiac function and guide fluid management. There were no signs of systemic thrombosis, although the free flap reconstruction was abandoned because of a thrombus in the vascular anastomosis. Cardiac function can deteriorate in APS patients because of coronary and/or microvascular thrombosis. Therefore, it is necessary to evaluate cardiac function, regardless of a known history of cardiovascular disease. Moreover, additional monitoring (ie, SVV) may be useful during prolonged general anesthetics for patients with APS and cardiac dysfunction.

Erythrocytosis, embolism in a woman with antiphospholipid antibodies: A diagnostic challenge

Systemic thromboembolism, along with acute multiorgan failure, should raise clinical suspicion for CAPS. Timely management, even in suspected cases, can have a significant impact on mortality.

Catastrophic antiphospholipid syndrome presented as ruptured papillary muscle during puerperium in a patient with systemic lupus erythematosus

INTRODUCTION

Catastrophic antiphospholipid syndrome (CAPS) is a rare and serious phenomenon that requires prompt recognition and treatment.

CASE PRESENTATION

The authors present the case of a puerperal woman with systemic lupus erythematosus (SLE) admitted to the emergency room with headache, blurred vision, thoracic pain, and purpuric lesions on both ears. Echocardiogram revealed global decrease in left ventricular function while cardiac and inflammatory markers were elevated. Three days after admission she developed cardiogenic shock due to rupture of mitral papillary muscle which required emergent cardiac surgery, with replacement of the mitral valve; treatment with anticoagulation, high-dose glucocorticoids, and intravenous immunoglobulins were initiated. Cardiac and brain MRI revealed signs of ischemic lesions in both organs. Histopathology analysis of the placenta and papillary muscle showed signs of ischemia secondary to microvascular thrombosis. Based on the clinical demonstration of thrombosis in three organs, and the presence of lupus anticoagulant antibodies, a diagnosis of probable CAPS was established.

CONCLUSION

This case highlights the importance of a high level of suspicion of CAPS, particularly in patients with risk factors, and the value of immediate adequate treatment. Moreover, the rupture of a papillary muscle with histologically consistent signs of antiphospholipid syndrome expands the spectrum of involvement of this disease and should be considered as a rare but life-threatening possibility in patients with myocardial injury.

A Fatal Case of Diffuse Alveolar Hemorrhage in the Setting of Systemic Lupus Erythematosus: A Case Report and Review of Noninfectious Causes of Acute Pulmonary Hemorrhage in Adults

Systemic lupus erythematosus (SLE) is an autoimmune connective tissue disease, characterized by autoantibody production and immune complex formation, that has the potential to affect virtually any organ. Pleuropulmonary involvement occurs in 50–70% and commonly manifests as pleuritis and pleural effusion. Diffuse alveolar hemorrhage (DAH) is a rare manifestation of SLE. Most cases of DAH occur in young adults with an underlying autoimmune disease such as systemic vasculitis or Goodpasture syndrome. SLE is typically lower on the list of initial differential diagnoses of DAH due to its rarity compared to other etiologies. We present a case of a patient with dyspnea on exertion, dry coughs, lower extremity edema, and intermittent periorbital edema who ultimately succumbed to respiratory failure secondary to DAH in the setting of SLE. The diagnosis of SLE was suspected clinically and confirmed at autopsy due to her rapid clinical deterioration. DAH requires prompt intervention, and management is guided by the underlying disease process. SLE is a potentially treatable disease; therefore, timely diagnosis is important in order to exclude other noninfectious causes of DAH (reviewed in this report) and to initiate appropriate therapy.

A 36-Year-Old Woman Presenting With Left Upper Quadrant Discomfort, Encephalopathy, and Respiratory Failure

CASE PRESENTATION

A 36-year-old woman with a history of hypertension and alcoholism reported 2 days of left upper quadrant pain and jaundice. Within hours of admission, she became somnolent and hypoxic. The patient was then intubated. She had no history of drug abuse, cigarette smoking, liver disease, autoimmune disease, or pancreatitis. She had no home medications.

Severe mesenteric ischemia with multiple organ failure in a patient previously treated with a humanized monoclonal antibody against programmed death receptor-1 (pembrolizumab), a case of pembrolizumab associated catastrophic antiphospholipid syndrome?

Immune checkpoint inhibitors are used in the treatment of different types of tumors including melanoma and non-small cell lung carcinoma. The use of these inhibitors is associated with a broad spectrum of immune-related adverse effects. Here we report a case of a patient admitted to the intensive care unit with multiple organ failure due to catastrophic antiphospholipid syndrome following treatment with pembrolizumab, an immune checkpoint inhibitor, because of metastatic melanoma. The presented patient had multiple organ failure of lung, gastro-intestinal, renal, and the liver. Vascular thrombosis was confirmed by both imaging (pulmonary embolism on computed tomography–thorax) and histopathological examination of the intestines. In combination with the presence of IgA anti-cardiolipin antibodies and initially IgM anti-cardiolipin antibodies, catastrophic antiphospholipid syndrome was suspected. Despite treatment with plasmapheresis and corticosteroids, the patient died due to multiple organ failure. Catastrophic antiphospholipid syndrome is difficult to recognize and has high mortality rates despite supportive treatment. In this case report, discussion is provided regarding the possible immunological mechanism behind catastrophic antiphospholipid syndrome during or after treatment with immune checkpoint inhibitors. It is important to realize that in modern intensive care unit, more patients with immune-related adverse effects of the treatment with immune checkpoint inhibitors will be admitted, because of an increase in the number of patients treated with these checkpoint inhibitors. When these patients are admitted on the intensive care unit, multi-disciplinary consultation is important because of the difficulty of early recognition and optimal treatment of these possible lethal side effects.

Antiphospholipid syndrome

Antiphospholipid syndrome is one of the more common acquired causes of hypercoagulability. Its major presentations are thrombotic (arterial, venous, or microvascular) and pregnancy morbidity (miscarriages, late intrauterine fetal demise, and severe pre-eclampsia). Classification criteria include 3 different antiphospholipid antibodies: lupus anticoagulant, anticardiolipin, and anti-beta 2 glycoprotein I. Management includes both preventive strategies (low-dose aspirin, hydroxychloroquine) and long-term anticoagulation after thrombosis.

Therapeutic Challenges with Catastrophic Antiphospholipid Antibody Syndrome: A Case Report

Antiphospholipid antibody syndrome (APS) is a multisystem disorder characterized by thromboembolic events in the presence of antiphospholipid antibodies (APLA). Catastrophic antiphospholipid antibody syndrome (CAPS) is an uncommon variant of APS which is associated with widespread coagulopathy that predominantly affects small vessels. Despite maximal treatment, CAPS has a very high mortality rate. We present a case of a 42-year-old woman with a history of APS who presented to our hospital with complaints of epistaxis, hemoptysis, menorrhagia, and shortness of breath. She was diagnosed with CAPS and developed multiorgan failure and sepsis. Despite maximal treatment with immune modulators, she unfortunately succumbed. With this case, we highlight the importance of early recognition of CAPS and review various treatment modalities that have been proven beneficial. Despite these modalities, CAPS remains a therapeutic challenge in many cases and has a high mortality rate.

Adrenal failure and antiphospholipid syndrome

We herein report two cases of primary adrenal insufficiency (AI) associated with antiphospholipid syndrome (APS). In both patients, the main finding that led to the diagnosis was hyponatraemia. The major difference between the two cases was the time at which AI evolved during the course of APS. In the first patient, AI developed acutely along with other presenting features of APS. In the second patient, the AI was unmasked during a stressful situation induced by severe inflammation that occurred 7 years after the first APS manifestation and had probably evolved slowly during the previous few years. These cases emphasise the importance of considering AI in patients with either suspected or newly diagnosed APS as well as in patients who have long been known to have APS. The symptoms and signs alerting the clinician to possible AI are general abdominal complaints, fever, hypotension, and hyponatraemia. Conversely, patients with primary AI should be questioned about the signs and symptoms of APS.

Improvements in diagnosis and risk assessment of primary and secondary antiphospholipid syndrome

Classification criteria for antiphospholipid syndrome have not been updated since the revised Sapporo classification criteria were published in 2006. These criteria have limitations in that they omit nonclassical manifestations (hematologic and neurologic), include anticardiolipin and anti-β2-glycoprotein I immunoglobulin (Ig)M isotypes, and do not separately consider primary (no autoimmune disease) or secondary (usually systemic lupus erythematosus) disease. Recent findings in antiphospholipid antibody include fluctuation of antiphospholipid antibodies, recognition that IgA isotypes do confer risk, identification of the role of complementopathy in catastrophic antiphospholipid syndrome, and elucidation of the role of thrombosis risk equations.

Genetics of Antiphospholipid Syndrome

PURPOSE OF REVIEW

Antiphospholipid syndrome (APS) is a rare heterogenous disorder associated with the presence of antiphospholipid antibodies and can present in a wide variety of clinical manifestations including thrombosis and pregnancy complications. Although the etiology of APS remains poorly understood, there is strong support for considering APS as a complex genetic disease in which multiple genetic risk factors, in conjunction with environmental factors, affect its onset, progression, and severity. Here, we provide a comprehensive review of the current knowledge of the genetic basis of APS, which remains in its infancy.

RECENT FINDINGS

Most genetic studies to date in APS were performed in small cohorts of patients. As a result, only few genetic associations reported are convincing. Several reports suggested genetic associations with HLA class II alleles in APS, and only two genetic loci outside of the HLA region (STAT4 and C1D) reached the threshold for genome-wide level of significance (P < 5 × 10^-8). In this review, we also shed light on the genetic differences among the diverse clinical subsets of APS and briefly discuss the role that DNA methylation changes might play in the pathophysiology of this disease. The genetic basis of APS remains poorly characterized. Larger collaborative multicenter studies using well-characterized patients are needed to comprehensively understand the role of genetic susceptibility in APS.

Plasma exchange in catastrophic antiphospholipid syndrome

Plasma exchange is a well-established therapeutic procedure commonly used in many autoimmune disorders. The beneficial effects of plasma exchange are thought to occur through the elimination of pathogenic mediators found in plasma, including autoantibodies, complement components, and cytokines. The catastrophic antiphsopholipid syndrome (CAPS) is a life-threatening variant of the antiphospholipid syndrome (APS) where several thrombosis take place in a short period of time in patients with circulating antiphospholipid antibodies. The triple therapy with anticoagulation, corticosteroids and plasma exchange or intravenous immunoglobulins has been proposed in CAPS. CAPS is a rare disease precluding the conduction of formal clinical trials. However, the observation of a better clinical course of patients who received this treatment supports their use. Plasma exchange has become an established therapeutic procedure in CAPS but there are no studies regarding the better approach and thus its use relies on the experience of the physicians in charge. The current article aims to review potential mechanisms of action of plasma exchange and the technical aspects of this procedure and will focus on its current role in CAPS, the experience published in treating this condition and the treatment protocol that we use in our institution.

Clinical characteristics and risk factors of microvascular involvement in primary antiphospholipid syndrome: a longitudinal single-center study in China

OBJECTIVES

The objective of this study was to investigate risk factors of microvascular involvement and survival in Chinese patients with primary antiphospholipid syndrome.

METHODS

In this single-center, retrospective study, we enrolled 112 patients with a confirmed diagnosis of primary antiphospholipid syndrome who were admitted to Peking Union Medical College Hospital from January 2004 to December 2016. Demographic data, clinical characteristics, laboratory results, and follow-up records were collected.

RESULTS

A total of 112 patients with primary antiphospholipid syndrome were studied. Microvascular involvement was identified in 21 patients (18.75%). Patients with microvascular involvement experienced fewer episodes of arterial or venous thrombosis (28.6% vs. 84.6%) and a higher incidence of thrombocytopenia (85.7% vs. 54.9%), respectively. Low complement and elevated high-sensitivity CRP levels were observed more frequently in the microvascular group compared with the non-microvascular group (complement 38.1% vs. 18.7%; high-sensitivity CRP 71.4% vs. 31.9%, respectively). Anti-β2-glycoprotein I antibodies were more prevalent in patients with microvascular involvement than in patients without (66.7% vs. 33.0%, respectively). Multivariate logistic regression analysis revealed that thrombocytopenia (odds ratio = 4.523, 95% confidence interval 1.139-17.962), elevated high-sensitivity CRP levels (odds ratio = 6.385, 95% confidence interval 1.969-20.704), and anti-β2-glycoprotein I antibody positivity (odds ratio = 5.042, 95% confidence interval 1.555-16.352) were independent risk factors for microvascular involvement. A Kaplan-Meier analysis revealed that survival was significantly poorer in patients with microvascular involvement compared with patients without (p = 0.0278).

CONCLUSIONS

In addition to arterial and venous thrombosis, antiphospholipid syndrome can affect the microvasculature of select organs. It is thus important for clinicians to be aware that antiphospholipid syndrome-associated microvascular involvement has a unique pathogenesis and can be a life-threatening condition.

Clinical Insights into Diffuse Alveolar Hemorrhage in Antiphospholipid Syndrome

PURPOSE OF REVIEW

Diffuse alveolar hemorrhage (DAH) is a rare but devastating manifestation of antiphospholipid syndrome (APS) patients with or without other systemic autoimmune diseases. Data regarding diagnosis and treatment are limited to case series. We review diagnostic and therapeutic strategies employed in APS patients with DAH and discuss our experience in managing these complex patients.

RECENT FINDINGS

Pulmonary capillaritis likely contributes to the pathogenesis, however is only observed in half of the biopsies. Corticosteroids induce remission in the majority of patients, however almost half recur and require a steroid-sparing immunosuppressive to maintain remission. Cyclophosphamide- or rituximab-based regimens achieve the highest remission rates (50%); other strategies include intravenous immunoglobulin, plasmapheresis, mycophenolate mofetil, and/or azathioprine. Given the rarity of DAH in APS, treatment is guided by interdisciplinary experience. Why certain patients achieve full remission with corticosteroids while others require immunosuppressive agents is unknown; future research should focus on the pathophysiology and optimal management.

Clotting Catastrophies in the Intensive Care Unit

Clotting catastrophies are rarely encountered challenges in the Intensive Care Unit (ICU) and their presentation and progress maybe devastating and fulminant. Dramatic onset and involvement of multiple vascular beds should alert the clinician to look for these disorders. Outcomes may be improved with rapid diagnosis and prompt institution of specific therapies and interdisciplinary liaison holds the key to success.

Prevalence and Significance of Non-conventional Antiphospholipid Antibodies in Patients With Clinical APS Criteria

Background: The biological diagnostics of antiphospholipid syndrome (APS) takes into account the persistent positivity for anticardiolipin and/or anti-β2GP1 antibodies and/or presence of lupus anticoagulant (LA). However, some non-conventional antiphospholipid antibodies have emerged that could help in the diagnosis of APS.

Objectives: To study the potential usefulness of non-conventional antiphospholipid antibodies in clinical practice.

Methods: Eighty-seven patients, aged from 15 to 92 years were included and classified in following groups: 41 patients positive for the conventional antibodies with clinical criterion of APS (31 with primary APS and 10 secondary), 17 seronegative APS (SNAPS) patients (i.e., persistent negativity for the conventional antibodies with a strong clinical suspicion of APS), 11 asymptomatic antiphospholipid antibodies carriers (i.e., persistent positivity for the conventional antibodies without clinical evidence of APS), and 18 patients presenting with a first thrombotic or obstetrical event. IgG and IgM were detected to the following antigens: phosphatidylserine/prothrombin (PS/PT) by ELISA, and phosphatidic acid, phosphatidyl-ethanolamine, phosphatidyl-glycerol, phosphatidyl-inositol, phosphatidylserine, annexin V, prothrombin by immunodot. Anti-β2GP1 IgA, and anti-β2GP1 domain 1 IgG were detected by chemiluminescence.

Results: Positivity for the non-conventional antibodies was correlated with APS severity; patients with catastrophic APS (CAPS) being positive for 10.7 (Median, Range: 5–14) non-conventional antibodies. 9/17 seronegative patients were positive for at least one of non-conventional antibodies. A study of non-supervised hierarchical clustering of all markers revealed that anti-PS/PT antibodies showed high correlation with the presence of LA. All patients with APS triple positivity (highest risk profile) exhibited also persistent positivity for anti-PS/PT antibodies.

Conclusions: Our data obtained from a prospective cohort constituted mainly by patients with primary APS, suggest that non-conventional APS antibodies may be useful for patients classified as SNAPS. They demonstrate the potential value of aPS/PT antibodies as a strong marker of APS. We propose that anti-PS/PT antibodies could be a surrogate APS biological marker of LA to classify in high-risk profile patients treated by direct oral anticoagulants (DOACs), in whom LA detection cannot be achieved.

Microangiopathies in pregnancy

Thrombotic thrombocytopenic purpura (TTP) is a potentially reversible, life-threatening medical emergency. We present a case of a 21-year-old female with evidence of haemolytic anaemia based on the presence of positive markers of haemolysis. Negative Coomb's test, thrombocytopenia and placental infarcts raised suspicion for a thrombotic microangiopathy. She was diagnosed with TTP and managed with emergency plasma exchange. Her recovery was immediate.A presumptive diagnosis of TTP should be based on the presence of microangiopathic haemolytic anaemia with thrombocytopenia and plasma exchange should be initiated while complete work up is pending. Using the regular pentad solely for diagnosis of TTP will lead to underdiagnosis of many cases and should be avoided.Several microangiopathies can be seen during pregnancy including TTP/atypical haemolytic uraemic syndrome, HELLP syndrome, pre-eclampsia, disseminated intravascular coagulopathy and antiphospholipid antibody syndrome. Distinction between each type will be the focus of our discussion as treatment decisions differ accordingly.

The Differences Between Childhood and Adult Onset Antiphospholipid Syndrome

Antiphospholipid syndrome (APS) is a rare autoimmune disease of unknown etiology that represents a leading cause of acquired thromboembolism and recurrent miscarriage. It is characterized by the persistent elevated presence of pathogenic antiphospholipid auto-antibodies directed against cardiolipin, ß2-glycoprotein-I, and/or a positive lupus anticoagulant test. As with many autoimmune disorders, the pathogenesis of APS is believed to be the result of a complex interaction between environmental triggers and genetic predisposition. Although more common in adults, APS occasionally manifests in the neonatal period and throughout childhood. Adut-onset APS classification criteria are poorly validated to the pediatric population (in which pregnancy related complications are seldom seen) and as a result, assessment of the prevalence of the disease in childhood is difficult. Thromboembolic events seen in children include deep venous thrombosis in addition to stroke and pulmonary embolism, which can lead to significant long-term disability. The disease can be classified as either primary (when occurring in isolation) or secondary, in which the disease is diagnosed in the context of another underlying disease, most commonly systemic lupus erythematosus. A variety of laboratory and clinical difference are seen between pediatric and adult-onset APS. The marked female predominance seen in adult-onset disease is less evident in childhood where the gender split is more evenly spread. In addition, children with APS are at a higher risk of recurrent thromboembolism than adults. The treatment of childhood-onset APS is challenging due to a lack of large-scale prospective studies in the pediatric population. Therapeutic options are often based upon treatment guidelines that have been based upon literature from the adult-onset form of the disease. In the majority of cases, treatment is focused on the prevention of further thrombosis through treatment with long-term anti-coagulation therapy. The evidence for the use of antiplatelet agents (such as aspirin) and hydroxychloroquine is inconclusive. It is important to remember that anti-coagulation can have significant lifestyle implications for the child with APS and it is essential to consider potential implications relating to school and recreational activities, with contact sports often discouraged due to the increased risk of bleeding.

Vascular Manifestations in Antiphospholipid Syndrome (APS): Is APS a Thrombophilia or a Vasculopathy?

PURPOSE OF REVIEW

Antiphospholipid antibody syndrome (APS) is characterized primarily by thrombosis and pregnancy morbidity. Chronic vascular lesions can also occur. While the underlying mechanisms of these vascular lesions are not entirely known, there have been multiple theories describing the potential process of vasculopathy in APS and the various clinical manifestations associated with it.

RECENT FINDINGS

Recently, it has been demonstrated that endothelial proliferation in kidneys can be explained by the activation of the mammalian target of rapamycin complex (mTORC) pathway by antiphospholipid antibodies (aPL). These data support the existence of an APS-related vasculopathy in different locations which can explain-in part-the different manifestations of APS. This review focuses on the various manifestations of APS as a result of APS-related vasculopathy, as well as pathophysiology, current screening, and treatment options for clinicians to be aware of.

Kidney disease in primary anti-phospholipid antibody syndrome

APS is an autoimmune disease defined by the presence of arterial or venous thrombotic events and/or pregnancy morbidity in patients who test positive for aPL. APS can be isolated (primary APS) or associated with other autoimmune diseases. The kidney is a major target organ in APS, and renal thrombosis can occur at any level within the vasculature of the kidney (renal arteries, intrarenal vasculature and renal veins). Histological findings vary widely, including ischaemic glomeruli and thrombotic lesions without glomerular or arterial immune deposits on immunofluorescence. Renal involvement in patients with definite APS is treated with long-term anticoagulants as warfarin, but new treatments are being tried. The aim of this article is to review the links between primary APS and kidney disease.

A importância de reconhecer a síndrome antifosfolípide na medicina vascular

A síndrome antifosfolipíde (SAF) é uma doença autoimune sistêmica caracterizada por trombose arterial ou venosa recorrente e/ou morbidade gestacional e pela presença dos anticorpos antifosfolipídeos, podendo apresentar outras manifestações vasculares, como microangiopatia, arteriopatia crônica e SAF catastrófica. Determinados testes laboratoriais para a síndrome (por exemplo, o anticoagulante lúpico) podem sofrer interferência do uso de medicações anticoagulantes, dificultando o diagnóstico. A fisiopatologia da SAF é complexa, sendo enumerados no texto diversos mecanismos patogênicos relacionados à coagulação, ao endotélio e às plaquetas. Por fim, discutimos o tratamento da SAF de acordo com a presença e o tipo de manifestações clínicas, o uso dos anticoagulantes orais diretos e o manejo perioperatório de pacientes com SAF.

Microangiopathic antiphospholipid antibody syndrome due to anti-phosphatidylserine/prothrombin complex IgM antibody

Herein we describe a case of microangiopathic antiphospholipid syndrome (MAPS) due to anti-phosphatidylserine/prothrombin complex (aPS/PT) IgM antibody successfully treated with rituximab. A significant correlation was observed between the clinical course and the aPS/PT IgM antibody titer, which can rise earlier before the appearance of clinical symptoms. Rituximab can be safely and effectively used for MAPS. Although detection of only aPS/PT IgM antibody is rare, aPS/PT IgM antibody might be associated with the pathogenesis of MAPS and might be a useful marker of disease activity.