Outcome of primary antiphospholipid syndrome in childhood

Antiphospholipid syndrome in children

Antiphospholipid syndrome (APS) in children is a rare disease associated with significant morbidity and mortality. In comparison with APS in adults, pediatric APS has a more severe presentation with frequent recurrences of thrombotic events and a higher probability of life-threatening catastrophic APS. Nonthrombotic manifestations are also more common in the pediatric age group and can precede thrombosis. New classification criteria have been introduced recently and have not yet been assessed in pediatric patients with APS. In addition to anticoagulation drugs, other novel therapies have emerged including the use of B cell and complement inhibitors, especially in catastrophic APS. The purpose of this review is to provide a broad overview of aPL-related clinical manifestations in pediatric patients based on the analysis of published cohorts and data from the international pediatric APS registry. We also aim to illustrate APS in infants caused by transplacentally transferred maternal aPL, which is very rarely associated with acute thrombotic events in the perinatal period and more frequently with long-term neurodevelopmental abnormalities.

The role of coagulation factors VIII, IX and XI in the prediction and mediation of recurrent thrombotic events in children with non-central venous catheter deep vein thrombosis

BACKGROUND

The role of elevated coagulation factors VIII (FVIII), FIX, FXI for the prediction of recurrent thrombotic events in children after an index non-central venous catheter (non-CVC) related deep vein thrombosis (DVT) remains unclear.

OBJECTIVE

This study investigates the predictive role of FVIII, FIX, and FXI for recurrent thrombosis in children with index non-CVC DVTs, and the mediation effect of FVIII on chronic inflammation and recurrent thrombosis.

METHODS

Children aged 0-18 years diagnosed with an index non-CVC related DVT (1993-2020) were included in this single-center retrospective cohort study. Plasma levels of FVIII, FIX, FXI were measured cross-sectionally ≥30 days after the acute DVT. The association between the continuous variables FVIII, FIX, FXI and thrombosis recurrence was investigated using uni- and multivariable logistic regression, adjusting for age, sex, and chronic inflammation. Mediation analysis assessed the role of FVIII as a mediator between chronic inflammation and recurrent thrombosis. Ethics approval was obtained.

RESULTS

A total of 139 children with an index non-CVC related DVT were included. Thirty-eight (27 %) had a recurrent thrombosis at a median of 237 days (P25-P75 65-657 days) after the index DVT. In uni- and multivariable-analysis, FVIII, FIX or FXI did not predict thrombosis recurrence; However, chronic inflammation was an independent predictor. There was no evidence that FVIII mediated the effect of chronic inflammation on thrombosis recurrence.

CONCLUSION

We found no evidence that elevated FVIII, FIX or FXI predicted thrombosis recurrence, or evidence of a mediating role of FVIII. Underlying chronic inflammation predicted venous recurrent thrombotic events in this cohort.

Pediatric Presentation of Antiphospholipid Syndrome: A Review of Recent Literature With Estimation of Local Prevalence

We aimed to investigate the epidemiology, the clinical and laboratory characteristics of the pediatric involvement of antiphospholipid syndrome (APS), by performing a review of the current evidence and reviewing local experience in the Northwest Italy. To achieve this, we performed a detailed literature search to identify articles describing clinical and laboratory characteristics of pediatric APS. In concomitance, we conducted a registry-based study collecting data from the Piedmont and Aosta Valley Rare Disease Registry including pediatric patients diagnosed with APS in the last 11 years. The literature review led to inclusion of six articles with a total of 386 pediatric patients (65% females, 50% with systemic lupus erythematosus (SLE) as concomitant diagnosis). Rates of venous and arterial thrombosis were 57 and 35%, respectively. "Extra-criteria manifestations" included mostly hematologic and neurologic involvement. Almost one-quarter of patients (19%) reported recurrent events and 13% manifested as catastrophic APS. A total of 17 pediatric patients (mean age 15.1 ± 2.8, 76% female) developed APS in the Northwest of Italy. In 29% of cases, SLE was a concomitant diagnosis. Deep vein thrombosis was the most frequent manifestation (28%) followed by catastrophic APS (6%). The estimated prevalence of pediatric APS in Piedmont and Aosta Valley Region is 2.5/100,000 people, whereas the estimated annual incidence is 0.2/100,000 inhabitants. In conclusion, clinical manifestations of pediatric APS seem to be more severe and with a high prevalence of noncriteria manifestations. International efforts are needed to better characterize this condition and to develop new specific diagnostic criteria to avoid missed/delayed diagnosis in children with APS.

Autoimmune haemolytic anaemia and antiphospholipid antibodies in paediatrics: a systematic review and meta-analysis

INTRODUCTION/OBJECTIVE

The relationship between autoimmune haemolytic anaemia (AIHA) and antiphospholipid antibodies (aPL) has never been addressed via a meta-analysis in the paediatric age group. We evaluated the link between AIHA and aPL in childhood systemic lupus erythematosus (SLE) and antiphospholipid syndrome (APS).

METHODS

EMBASE and PubMed were screened from inception to May 2020 and Peto's odds ratio for rare events was employed for the between group comparisons.

RESULTS

The meta-analysis included 11 articles for a total of 575 children: the pooled prevalence of AIHA was greater in (1) IgG aCL-positive than IgG aCL-negative children (39.7% vs 20.9%, p = 0.005); (2) in APS-positive than APS-negative SLE children (36.8% vs 13.2%, p = 0.01); and (3) in SLE-related APS than in primary APS children (53% vs 16.2%, p = 0.008).

CONCLUSIONS

The pooled prevalence of AIHA is greatest in SLE with aPL/APS, low-moderate in SLE without aPL/APS, and lowest in primary APS. Key Points • Antiphospholipid antibodies strongly relate to autoimmune haemolytic anaemia. • Autoimmune haemolytic anaemia is more common in systemic lupus erythematosus with antiphospholipid antibodies.

Antiphospholipid syndrome and its role in pediatric cerebrovascular diseases: A literature review

Antiphospholipid syndrome (APS) or Hughes syndrome is an acquired thromboinflammatory disorder. Clinical criteria of APS diagnosis are large- and small-vessel thrombosis as well as obstetric problems; laboratory criteria are the presence of antiphospholipid antibodies (lupus anticoagulant, anticardiolipin antibodies and anti-β2-glycoprotein-1). The presence of at least 1 clinical and 1 laboratory criterion allows definitive diagnosis of APS. Primary APS is diagnosed in patients without features of connective tissue disease; secondary APS is diagnosed in patients with clinical signs of autoimmune disease. A high frequency of catastrophic APS as well as a high tendency to evolve from primary APS to secondary syndrome during the course of lupus and lupus-like disease is a feature of pediatric APS. The most characteristic clinical presentation of APS in the pediatric population is venous thrombosis, mainly in the lower limbs, and arterial thrombosis causing ischemic brain stroke. Currently, no diagnostic criteria for pediatric APS exist, which probably results in an underestimation of the problem. Similarly, no therapeutic procedures for APS specific for children have yet been established. In the present literature review, we discussed data concerning APS in children and its role in cerebrovascular diseases, including pediatric arterial ischemic stroke, migraine and cerebral venous thrombosis.

Pediatric antiphospholipid syndrome

Despite its potential to cause significant morbidity in children, pediatric antiphospholipid syndrome (APS) is an understudied condition. In this review, we will cover what is known about pediatric APS epidemiology and how the clinician might approach the diagnosis of pediatric APS. We will highlight similarities and differences with the adult disease, both for primary APS and in the context of lupus. Clinical manifestations beyond thrombosis, especially neurologic and hematologic in nature, will be discussed. We will also consider what unique implications antiphospholipid antibody-positivity may have for children with lupus and for neonates born to mothers with APS. The approach to treatment will be covered, including the unique impact of APS medications on children as compared with adults. Finally, the importance of future mechanistic research is emphasized as physicians endeavor to provide the personalized care that children with APS clearly deserve.

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.

What is known about pediatric antiphospholipid syndrome?

INTRODUCTION

Antiphospholipid syndrome (APS) is a systemic autoimmune disease characterized by vascular thrombosis and/or pregnancy morbidity associated with the persistent presence of antiphospholipid antibodies (aPL) including lupus anticoagulant (LA), anticardiolipin antibodies (aCL), and anti-β2 glycoprotein I antibodies (aβ2GPI).

AREAS COVERED

APS is considered as the most common acquired hypercoagulation state of autoimmune origin in children. Unfortunately, data about incidence, prevalence, thrombosis risk and effective treatment in paediatric APS are limited and unmethodical. Expert commentary: This review summarizes recent clinical, laboratory and therapy characterization of paediatric APS and emphasizes the differences between paediatric and adult populations.

European evidence-based recommendations for diagnosis and treatment of paediatric antiphospholipid syndrome: the SHARE initiative

Antiphospholipid syndrome (APS) is rare in children, and evidence-based guidelines are sparse. Consequently, management is mostly based on observational studies and physician's experience, and treatment regimens differ widely. The Single Hub and Access point for paediatric Rheumatology in Europe (SHARE) initiative was launched to develop diagnostic and management regimens for children and young adults with rheumatic diseases. Here, we developed evidence-based recommendations for diagnosis and treatment of paediatric APS. Evidence-based recommendations were developed using the European League Against Rheumatism standard operating procedure. Following a detailed systematic review of the literature, a committee of paediatric rheumatologists and representation of paediatric haematology with expertise in paediatric APS developed recommendations. The literature review yielded 1473 articles, of which 15 were valid and relevant. In total, four recommendations for diagnosis and eight for treatment of paediatric APS (including paediatric Catastrophic Antiphospholipid Syndrome) were accepted. Additionally, two recommendations for children born to mothers with APS were accepted. It was agreed that new classification criteria for paediatric APS are necessary, and APS in association with childhood-onset systemic lupus erythematosus should be identified by performing antiphospholipid antibody screening. Treatment recommendations included prevention of thrombotic events, and treatment recommendations for venous and/or arterial thrombotic events. Notably, due to the paucity of studies on paediatric APS, level of evidence and strength of the recommendations is relatively low. The SHARE initiative provides international, evidence-based recommendations for diagnosis and treatment for paediatric APS, facilitating improvement and uniformity of care.

A retrospective review of pediatric antiphospholipid syndrome and thrombosis outcomes

: Pediatric antiphospholipid syndrome (APS) is characterized by vascular thromboses and multisystem involvement associated with persistently positive antiphospholipid antibodies testing. There is limited literature regarding risk factors for development of thrombosis and long-term thrombotic outcomes in pediatric APS. The objective of our study was to review our institutional experience with pediatric APS and thrombosis outcomes. We conducted a 20-year retrospective review to study the clinical features, management, and long-term outcomes of patients between ages 6 months and 18 years diagnosed with APS. Seventeen patients (7 female; 10 male), with median age at first thrombosis being 15.3 years (range: 0.63-17.98 years) were included. The median follow-up period was 4.3 years (range: 0.8-16.9 years). Venous thrombosis was noted in 11 patients (64.7%) with arterial events occurring in six patients (35.3%). Nine (53%) patients were noted to have primary APS. Recurrent and/or progressive thrombotic events occurred in 10 patients (58.8%), which is higher than reported literature. The median time for recurrence/progression was 1.4 years (range: 0.37-11.85 years). At the time of recurrence/progression, only two (20%) patients were at therapeutic levels of anticoagulation. The high recurrence rate with majority of patients not being on therapeutic levels of anticoagulation at the time of the event along with 60% of recurrent events occurring at least 1 year from first vascular event suggests the possible need for long-term anticoagulation. However, larger pediatric studies are required to assess the need for long-term/indefinite anticoagulation.

Diagnosis and treatment of antiphospholipid syndrome in childhood: A review

The antiphospholipid syndrome (APS) is a multisystem autoimmune disease characterized by recurrent fetal loss and thromboembolic events associated with the presence of elevated titres of antiphospholipid antibodies (aPL). The purpose of this review is to summarize what is currently known about the diagnosis and treatment of pediatric APS, to highlight key differences between APS presenting in adults versus children throughout, and to identify areas where future research is needed.

Immune-Mediated Diseases of the Central Nervous System: A Specificity-Focused Diagnostic Paradigm

Immune-mediated diseases of the central nervous system show wide variability both symptomatically and with respect to underlying pathophysiology. Recognizing aberrant immunologic activity as the cause of neurologic dysfunction requires establishing as precise a neuroanatomic and functional phenotype as possible, and a diagnostic and therapeutic strategy that stabilizes the patient, excludes broad categories of disease via rapidly available diagnostic assays, and maintains a broad differential diagnosis that includes immune-mediated conditions. This process is aided by recognizing the appropriate clinical circumstances under which immune-mediated disease should be suspected, and how to differentiate these conditions from other causes of similar neurologic dysfunction.

Pediatric antiphospholipid syndrome

Antiphospholipid syndrome (APS) is a multisystem autoimmune condition characterized by vascular thromboses associated with persistently positive antiphospholipid antibodies. There is currently a paucity of data (incidence, prevalence, thrombosis risk, and effective treatment) in pediatric APS. The purpose of this report is to review the current literature on APS in children and neonates, identify the gaps in current knowledge, and suggest avenues for studies to fill those gaps.

High prevalence of prothrombotic abnormalities in multifocal osteonecrosis: description of a series and review of the literature

Multifocal or multiple osteonecrosis (ON), defined by the involvement of 3 or more anatomic sites, is unusual, being observed in only 3%-10% of patients diagnosed with ON. We report the clinical characteristics of a cohort of 29 patients with multifocal ON from a single center and evaluate the prevalence of associated prothrombotic abnormalities in 26 of these patients. We conducted a retrospective study of all patients diagnosed with multifocal ON evaluated in our institution during the last 20 years. We recorded clinical manifestations and underlying diagnoses. A wide thrombophilic profile was performed, including antithrombin, protein C, protein S, lupus anticoagulant, anticardiolipin antibodies, activated protein C resistance, factor V Leiden, mutation G-20210-A of the prothrombin gene, and factor VIII. Coagulation test results were compared with those in a healthy control group and a group of patients with history of lower-extremity deep venous thrombosis. The mean age of the patients was 49.2 ± 15 years (range, 28-81 yr). The mean number of ON localizations per patient was 5.2 ± 2.3 (range, 3-11). Hips were the most commonly affected joint (82%), followed by knees (58%), shoulders (37%), and ankles (13%). Most patients had an underlying disease process, and 12 of 25 (48%) patients had coagulation test abnormalities. The most common alterations were high factor VIII levels and antiphospholipid antibody (aPL) positivity in 24% and 20% of cases, respectively. These abnormalities were more prevalent in patients with multifocal ON compared with patients in the control groups. Sixty-one percent of patients had a history of corticosteroid treatment. Patients with coagulation abnormalities had a higher number of ON localizations per patient (6.5 ± 2.7 vs. 3.88 ± 0.8; p = 0.002) and a higher prevalence of atypical ON localizations (25% vs. 0%; p = 0.05). In conclusion, in the present cohort of patients with multifocal ON, 48% of the patients had at least 1 prothrombotic factor, especially high levels of factor VIII and aPL. These findings have major implications for the diagnosis and treatment of multifocal ON and clearly indicate the need to perform a thrombophilic profile in these patients.

Catastrophic antiphospholipid syndrome: first signs in the neonatal period

The term "catastrophic" antiphospholipid syndrome (CAPS) is used to define a subset of the antiphospholipid syndrome (APS) characterized by the clinical evidence of three or more organ involvement by thrombotic events in a short period of time and with laboratory confirmation of the presence of antiphospholipid antibodies. We describe a male infant first admitted at 17 days old for necrotizing enteritis complicated by cardiac and renal failure. Because of progressive renal function deterioration, a renal biopsy was performed at 8 months old, and histopathologic examination was compatible with renal venous thrombosis. Laboratory searching for vascular, prothrombotic, and metabolic disease was negative. Five months later, he developed two different episodes (20-day range) of ischemic stroke. Genetic test for thrombophilic conditions was positive for two different mutations, and repeatedly high titers of lupus anticoagulant, anticardiolipin, and anti-β2glicoprotein I antibodies were found. He was treated successfully with anticoagulants and showed a favorable clinical evolution. To the best of our knowledge, this is the youngest patient reported with probable CAPS. Although rare, APS/CAPS in the neonatal period or in the first year of life must be suspected in infants presenting with thrombotic phenomena. The present case illustrates the importance of an early diagnosis and treatment to enhance possibilities of survival.

Primary antiphospholipid syndrome presenting as renal vein thrombosis and membranous nephropathy

Antiphospholipid syndrome is a multisystem auto-immune disorder characterized by thrombotic events and the presence of circulating antiphospholipid antibodies. Large vessel involvement in the form of thrombosis/stenosis and thrombotic microangiopathy is a commonly described renal finding. However, non-thrombotic glomerulopathies are increasingly being recognized in patients with antiphospholipid syndrome. We report a rare occurrence of both renal vein thrombosis and membranous nephropathy in a previously healthy adolescent male. Investigations revealed persistently positive antiphospholipid antibodies in the absence of an underlying systemic autoimmune disorder or malignancy. Our patient responded favourably to anti-proteinuric therapy and anticoagulation with complete resolution of proteinuria and a nearly occlusive thrombus.

The Ped-APS Registry: the antiphospholipid syndrome in childhood

In recent years, antiphospholipid syndrome (APS) has been increasingly recognised in various paediatric autoimmune and nonautoimmune diseases, but the relatively low prevalence and heterogeneity of APS in childhood made it very difficult to study in a systematic way. The project of an international registry of paediatric patients with APS (the Ped-APS Registry) was initiated in 2004 to foster and conduct multicentre, controlled studies with large number of paediatric APS patients. The Ped-APS Registry is organised as a collaborative project of the European Forum on Antiphospholipid Antibodies and Juvenile Systemic Lupus Erythematosus Working Group of the Paediatric Rheumatology European Society. Currently, it documents a standardised clinical, laboratory and therapeutic data of 133 children with antiphospholipid antibodies (aPL)-related thrombosis from 14 countries. The priority projects for future research of the Ped-APS Registry include prospective enrollment of new patients with aPL-related thrombosis, assessment of differences between the paediatric and adult APS, evaluation of proinflammatory genotype as a risk factor for APS manifestations in childhood and evaluation of patients with isolated nonthrombotic aPL-related manifestations.

Acute myocardial infarction as the presenting symptom of systemic lupus erythematosus

We report a case of acute myocardial infarction due to non-antiphospholipid-related coronary artery thrombosis as the presenting manifestation of systemic lupus erythematosus in a young patient. We present the acute workup and the results of successful transcatheter coronary intervention. The causes of acute myocardial infarction and coronary artery thrombosis in pediatric patients are reviewed.

Pediatric antiphospholipid syndrome: clinical and immunologic features of 121 patients in an international registry

OBJECTIVES

The purpose of this study was to obtain data on the association of antiphospholipid antibodies with clinical manifestations in childhood and to enable future studies to determine the impact of treatment and long-term outcome of pediatric antiphospholipid syndrome.

PATIENTS AND METHODS

A European registry extended internationally of pediatric patients with antiphospholipid syndrome was established as a collaborative project of the European Antiphospholipid Antibodies Forum and Lupus Working Group of the Pediatric Rheumatology European Society. To be eligible for enrollment the patient must meet the preliminary criteria for the classification of pediatric antiphospholipid syndrome and the onset of antiphospholipid syndrome must have occurred before the patient's 18th birthday.

RESULTS

As of December 1, 2007, there were 121 confirmed antiphospholipid syndrome cases registered from 14 countries. Fifty-six patients were male, and 65 were female, with a mean age at the onset of antiphospholipid syndrome of 10.7 years. Sixty (49.5%) patients had underlying autoimmune disease. Venous thrombosis occurred in 72 (60%), arterial thrombosis in 39 (32%), small-vessel thrombosis in 7 (6%), and mixed arterial and venous thrombosis in 3 (2%). Associated nonthrombotic clinical manifestations included hematologic manifestations (38%), skin disorders (18%), and nonthrombotic neurologic manifestations (16%). Laboratory investigations revealed positive anticardiolipin antibodies in 81% of the patients, anti-beta(2)-glycoprotein I antibodies in 67%, and lupus anticoagulant in 72%. Comparisons between different subgroups revealed that patients with primary antiphospholipid syndrome were younger and had a higher frequency of arterial thrombotic events, whereas patients with antiphospholipid syndrome associated with underlying autoimmune disease were older and had a higher frequency of venous thrombotic events associated with hematologic and skin manifestations.

CONCLUSIONS

Clinical and laboratory characterization of patients with pediatric antiphospholipid syndrome implies some important differences between antiphospholipid syndrome in pediatric and adult populations. Comparisons between children with primary antiphospholipid syndrome and antiphospholipid syndrome associated with autoimmune disease have revealed certain differences that suggest 2 distinct subgroups.

The clinical spectrum of antiphospholipid syndrome

Antiphospholipid syndrome (APS) is a disorder characterized by a wide variety of clinical manifestations. Virtually any organ system or tissue may be affected by the consequences of large- or small-vessel thrombosis. There is a broad spectrum of disease among individuals with antiphospholipid antibodies (aPL). Patients may exhibit clinical features suggesting APS but not fulfill the International Criteria for a "definite" diagnosis. Seronegative APS patients demonstrate typical idiopathic thromboses but aPL are not initially detected. Patients defined with definite APS demonstrate nearly identical sites of venous and arterial thrombosis, regardless of the presence or absence of systemic lupus erythematosus. Microangiopathic APS may present with isolated tissue and organ injury or as the overwhelming "thrombotic storm" observed in catastrophic APS.

Antiphospholipid antibodies in pediatric systemic lupus erythematosus and the antiphospholipid syndrome

The antiphospholipid syndrome (APS) is recognized increasingly as the most common acquired hypercoagulation state of autoimmune etiology and may occur as an isolated clinical entity (primary APS) or in association with an underlying systemic disease, particularly systemic lupus erythematosus (SLE). The major differences between pediatric and adult APS include absence of common acquired risk factors for thrombosis, absence of pregnancy-related morbidity, increased incidence of infection-induced antibodies, differences in cut-off values for determination of aPL and specific factors regarding long-term therapy in children. APS in children has been largely reported in patients with arterial or venous thromboses and less frequently in association with neurological or hematological manifestations. The presence of aPL in pediatric SLE can modify the disease expression and may be an important predictor of the development of irreversible organ damage. Two recently established international registries of neonates and children with APS provide a good opportunity to conduct large, prospective studies on the clinical significance of aPL and long-term outcome of pediatric APS.

Antiphospholipid syndrome in pediatrics

APS is recognized increasingly as a leading cause of vascular thrombosis in the pediatric population. With the obvious exception of pregnancy morbidity, most of the clinical features that may occur in adults with APS have been described also in children. Because the coincident prothrombotic factors that are common in adults have little or no impact in children, pediatric patients with APS constitute a suitable sample to investigate the relationship of aPL with the associated clinical manifestations, such as thrombocytopenia, hemolytic anemia, chorea, and livedo reticularis, and the specificities of aPL that are more linked to thrombosis. On the other hand, because of the high frequency of infectious processes in early life, children may have a greater prevalence of nonpathogenic and transient aPL. For these reasons, the diagnostic and therapeutic approach to APS in childhood may be different from that for adults. Because of the rarity of aPL-related thrombosis in children, the natural history and optimal management can be defined only through large, multicenter, controlled studies. A internet-based registry for pediatric patients with APS (Ped-APS Register) has been recently established as part of the activities of the Euro-aPL Forum and the Lupus Working Group of the Pediatric Rheumatology European Society. This registry is aimed to obtain information on APS in childhood, particularly regarding association of aPL with clinical manifestations, specificity of aPL, impact of treatment and long-term outcome (http://www.med.ub.es/MIMMUN/FORUM/PEDIATRIC.HTM).

Myocardial infarction in adolescents

OBJECTIVES

To determine the incidence, characteristics, and outcomes for adolescents diagnosed with acute myocardial infarction (AMI).

STUDY DESIGN

We analyzed data from the Nationwide Inpatient Sample to determine the incidence of AMI in adolescents (age 13 to 18 years). Data from 1998 to 2001 were analyzed. Patients with primary cardiomyopathies, congenital heart lesions, and previous heart transplantation were excluded.

RESULTS

The estimated incidence of AMI admissions of adolescents in the United States is 157 per year, or 6.6 events per 1 million patient-years. AMI occurs predominantly in males (80%). Reported incidences of substance abuse and smoking are significantly higher in the adolescents with AMI than in adolescents admitted to the hospital for other conditions (P < .001 for both). Of the 123 subjects with AMI that we studied, 36 underwent coronary angiography (29%) and 2 underwent coronary artery bypass graft surgery (1%). The hospital mortality rate was 0.8%.

CONCLUSIONS

AMI is extremely rare in adolescents. Patient characteristics associated with AMI include substance abuse, tobacco use, and male sex. The hospital survival for AMI in adolescents is excellent, and the need for catheter or surgical coronary artery intervention is uncommon.

Antiphospholipid antibodies in Turkish children with thrombosis

Antiphospholipid syndrome is a systemic disorder characterized by arterial and/or venous thrombosis, thrombocytopenia, recurrent fetal loss, and presence of antiphospholipid antibodies (APA). The importance of APA in Turkish children with thrombosis is unknown. This study aimed to evaluate the frequency of APA positivity, associated risk factors other than APA, and outcome in children with APA and thrombosis. The presence of APA was investigated in 138 children presenting for evaluation of thrombosis; other prothrombotic risk factors were also studied. The frequency of APA positivity among 138 children was 11.6% (16/138). The mean age of these 16 children (10 female, 62.5%) was 9.57 +/- 4.59 years (range, 2.5-18.0 years). The mean follow-up period was 31.7 +/- 21.7 months (range, 5-60 months). Recurrence was observed during follow-up in two patients (12.5%). Ten patients (62.5%) had arterial thrombosis, five patients (31.3%) venous thrombosis, and one patient (6.3%) purpura fulminans. Among the thrombotic children with APA, 11 (68.8%) had more than one prothrombotic risk factor other than circulating APA [five patients (31.3%) had two risk factors, two patients (12.5%) had three, and four patients (25.0%) had four]. Five patients (31.3%) had no additional risk factors. APA should be tested in all children with thrombosis, especially those with arterial thrombosis.

Antiphospholipid syndrome and recurrent thrombosis in children

OBJECTIVE

Few studies have addressed antiphospholipid syndrome (APS) among children. Our aims were to analyze the clinical and laboratory manifestations in a pediatric APS cohort and to assess the influence of inherited thrombophilia factors on the outcome of children with APS.

METHODS

This was a multicenter study of children with APS who had no previous systemic autoimmune disease. We retrospectively reviewed their clinical and laboratory data, including hereditary thrombophilic deficits and outcomes.

RESULTS

The cohort comprised 28 patients (17 females, mean +/- SD age at onset 10.6 +/- 6.1 years). The most common initial manifestations of APS were venous thrombosis, stroke, and thrombocytopenia. Lupus anticoagulant was detected in 96% of those tested. After a mean +/- SD followup of 5.7 +/- 4.8 years, 16 children (57.1%) had central nervous system disease, 9 exhibited hematologic involvement, and 5 (all females) had systemic lupus erythematosus (SLE). None had renal, heart, or new skin disease. Seven of 24 patients exhibiting vascular thrombotic events had recurrences. Infants with perinatal stroke had monophasic disease, and other manifestations of APS did not develop later. Hereditary thrombophilia was more common in children who experienced a single episode of APS (8 [53.3%] of 15 patients) than in those who experienced recurrences (2 [28.6%] of 7 patients). However, only 2 patients in the latter group (28.6%) received anticoagulants after the first manifestation, compared with 12 (70.6%) of the 17 patients without recurrences.

CONCLUSION

APS in children has unique features. SLE may develop in a significant percentage of girls presenting with APS. Hereditary thrombophilia did not predict recurrent thrombosis, whereas the preventive impact of anticoagulant treatment following the first thrombotic event was noteworthy.

Pediatric antiphospholipid syndrome

APS is rare in the pediatric age, but it represents an interesting phenomenon because most of the known "second hit" risk factors such as atherosclerosis, smoking, hypertension, contraceptive hormonal treatment, and pregnancy are not present in childhood. This could also be the reason for the prevalence of some clinical manifestations rather than others in PAPS. On the other hand, the increased frequency of infectious processes in the childhood age is likely responsible for the relatively high prevalence of non-pathogenic and transient aPL. Such points raise the problem of a different diagnosis or monitoring approach in pediatric APS. Of particular interest is the special entity of neonatal APS, which represents an in vivo model of acquired autoimmune disease, in which transplacentally acquired aPL cause thrombosis in the newborn. International registries for pediatric and neonatal APS are currently in place; epidemiologic, clinical, and laboratory re-search will help to shed light on all the still obscure aspects of this fascinating but rare disorder in the very young. Finally, treatment is less aggressive overall in pediatric APS, given the reluctance to anticoagulate children over the long term. Studies on the outcome of pediatric APS and the relative risks of prolonged anticoagulation in children are necessary to determine the type and duration of anticoagulation therapy.

Antiphospholipid antibodies associated with malignancies: clinical and pathological characteristics of 120 patients

OBJECTIVE

To describe the different types of malignancies associated with antiphospholipid antibodies (aPL).

METHODS

We performed a computer-assisted (MEDLINE, National Library of Medicine, Bethesda, MD) search of the literature from 1966 to 2003 to identify all cases of malignancies having aPL.

RESULTS

One hundred twenty patients were found. The mean age was 56+/-17 years (range 5 to 88). Sixty-two (52%) patients were men and 58 (48%) were women. A heterogeneous group of malignancies were found. Regarding hematological malignancies, 10 (8%) patients suffered from B-cell lymphoma, 8 (7%) from spleen lymphoma, 7 (6%) from chronic myeloid leukemia, and 6 (5%) from non-Hodgkin's lymphoma (NHL). Regarding solid tumors, renal cell carcinoma was diagnosed in 7 (6%) patients, primary tumor with unknown origin in 7 (6%), lung adenocarcinoma in 6 (5%), breast carcinoma in 6 (5%), and melanoma in 6 (5%). The main aPL-related manifestations were thrombocytopenia (25%), cerebrovascular accidents (24%), deep vein thrombosis (19%), pulmonary embolism (15%), and heart valve lesions (9%). In 17 cases, catastrophic antiphospholipid syndrome was considered to be triggered by the malignancy. Seventy-one (63%) of 113 patients recovered or are still alive after cancer treatment. Twenty-three (35%) of 65 patients achieved aPL remission after proper treatment of the malignancy.

CONCLUSIONS

It is important to bear in mind, especially in elderly patients, that thrombotic events associated with aPL can be the first manifestation of malignancy. At the same time, the presence of aPL in patients with malignancies has important implications in their treatment and prognosis.

Long-term follow-up in 128 patients with primary antiphospholipid syndrome: do they develop lupus?

We retrospectively studied a large cohort of patients with primary antiphospholipid syndrome (APS) from 4 different referral centers to analyze the clinical and serologic features and, specifically, to determine the number of patients going on to develop systemic lupus erythematosus (SLE) or other autoimmune disease after long-term follow-up. The study included 128 unselected patients with primary APS who fulfilled the Sapporo International Criteria from 4 different tertiary hospitals in the United Kingdom, Mexico, and Spain. The patients had attended the referral centers between January 1987 and July 2001. We reviewed clinical and serologic characteristics according to a pre-established protocol. We used univariate analysis with the chi-squared or Fisher exact test and logistic regression to analyze possible factors related to the coexistence of SLE and APS. Ninety-seven female and 31 male patients fulfilled the criteria, with a median age of 42 +/- 12 years (range, 16-79 yr), and with a mean follow-up of 9 +/- 3 years (range, 2-15 yr). The main manifestations included deep vein thrombosis in 62 patients (48%), arterial thrombosis in 63 (49%) patients, pregnancy loss in 177/320 (55%) cases, and pulmonary embolism in 37 (30%) patients. Other clinical manifestations were migraine in 51 (40%) patients, thrombocytopenia in 48 (38%), livedo reticularis in 47 (37%), and valvular disease in 27 (21%). Serologic findings were anticardiolipin antibodies (aCL) IgG positive in 110 (86%) patients, aCL IgM in 36 (39%), lupus anticoagulant in 71 (65%), antinuclear antibodies in 47 (37%), and positive Coombs test in 5 (4%) patients. During the follow-up and after a median disease duration of 8.2 years (range, 1-14 yr), 11 (8%) patients developed SLE, 6 (5%) developed lupus-like disease, and 1 (1%) developed myasthenia gravis. The remaining 110 patients (86%) continued to have primary APS. After the univariate analysis, a family history of lupus, the presence of Raynaud phenomenon, migraine, psychiatric features, multiple sclerosis-like features, hemolytic anemia, low C3 and C4, and Coombs positivity conferred a statistically significant risk for the subsequent development of SLE (p < 0.05). Only the presence of Coombs positivity had statistical significance (odds ratio, 66.4; 95% confidence interval, 1.6-2714; p = 0.027) after the logistic regression evaluation. The current study confirms that progression from primary APS to SLE or lupus-like disease is unusual, even after a long follow-up. Only 3 patients developed anti-dsDNA antibodies. The presence of a positive Coombs test might be a marker for the development of SLE in patients with primary APS.

Antiphospholipid syndrome

Antiphospholipid syndrome (APS) is a systemic autoimmune disorder characterized by a combination of arterial or venous thrombosis and recurrent fetal loss, accompanied by elevated titers of antiphospholipid antibodies (aPL). APS has been recognized as the leading cause of vascular thrombosis in children. The diagnostic and therapeutic approach to APS in childhood may be different from that for adults and because of the rarity of aPL-related thrombosis in children, the natural history and optimal management of APS can be defined only through large, multicenter, controlled studies.

Primary versus secondary antiphospholipid syndrome: is this lupus or not?

Antiphospholipid syndrome is a hypercoaguable state characterized by recurrent venous and/or arterial thrombosis and/or pregnancy complications of fetal loss, pre-eclampsia, or eclampsia in the presence of antiphospholipid antibodies. It was first described in the setting of systemic lupus erythematosus and subsequently recognized to also exist as an independent condition and in conjunction with a variety of other autoimmune, infectious, and malignant illnesses. These diseases have been called primary antiphospholipid syndrome and secondary antiphospholipid syndrome. However, the two conditions can have significant overlapping features. This paper reviews the similarities and the differences between the two conditions.

Vascular and connective tissue diseases in the paediatric world

Despite the fact that in recent decades many advances have been made in classification, outcomes measurements and therapeutic regimens, connective tissue diseases remain a challenge for paediatric rheumatologists. Corticosteroids are still the first choice therapy in juvenile systemic lupus erythematosus (SLE); however, it is time for a new therapeutic approach with immunosuppressant drugs in order to obtain a more prolonged survival and reduced organ system damage. A prevention of relapse of thromboembolic phenomena using low-dose aspirin is strongly suggested in children with anticardiolipin antibodies, particularly in those with SLE. The long-term prognosis in juvenile dermatomyositis is significantly improved due to a more aggressive treatment with corticosteroids and methotrexate. The treatment of Henoch-Schöenlein purpura is still under debate, and no agreement has been reached regarding the role of corticosteroids in the prevention of renal involvement. The management of the acute phase of Kawasaki disease is now well established, although there is controversy regarding the role of corticosteroids. It is still under debate how and whether to treat patients who do not fulfil the diagnostic criteria. Polyarteritis nodosa is a disease at risk of death and requires an aggressive approach with corticosteroids and immunosuppressants, while cutaneous polyarteritis needs a close control of an underlying streptococcus infection and prophylaxis with benzatin-penicillin to prevent relapses.