High prevalence of antiphospholipid antibodies in children with idiopathic cerebral ischemia

BACKGROUND

The presence of circulating antiphospholipid antibodies (aPLs) is frequently associated with thromboembolic phenomena.

OBJECTIVE

To investigate the prevalence of aPLs, detected as lupus anticoagulant (LA) or anticardiolipin antibody (aCL), in a group of unselected children with idiopathic cerebral ischemia.

DESIGN

Prospective, case series.

SETTING

A pediatric neurology department.

PATIENTS

Thirteen children with cerebral ischemia (eight with stroke, three with transient ischemic attacks, and two with ocular ischemia). Age-matched apparently healthy children served as controls.

MEASUREMENTS

LA and aCL determination was performed within 3 days after the occurrence of the ischemic event and was repeated after 3 to 6 months. To be defined as aPL-positive, patients had to have either a positive LA test or positive IgG and/or IgM aCL at moderate/high level in both determinations.

MAIN RESULTS

Ten (76%) of the 13 patients were positive for either LA or aCL. No differences were found between aPL-positive and aPL-negative patients with respect to clinical manifestations or radiological features. Six (46%) of the 13 patients had a history of multiple ischemic events.

CONCLUSIONS

Our results show a very high prevalence of aPLs in children with idiopathic cerebral ischemia. Because the presence of these antibodies has relevant therapeutic implications, their determination in children with cerebral ischemia is recommended.

Autoantibodies to human nuclear lamin B2 protein. Epitope specificity in different autoimmune diseases

The nuclear lamina of mammalian cells consists of three major proteins, lamins A, C, and B, and a fourth minor protein, lamin B2. Lamins belong to the family of intermediate filaments and are highly similar both in structure and primary sequence. They are organized in three well-defined domains: 1) a central alpha-helical rod, which is a secondary structure shared by all types of intermediate filaments, formed by three alpha-helices (coils 1A, 1B, and 2) and surrounded by 2) an amino-terminal head and 3) a carboxyl-terminal tail. Autoantibodies toward major lamin have been described previously in sera from patients with different autoimmune diseases. We chose an epitope mapping approach to further characterize the autoimmune response to nuclear lamin. Different lamin B2 domains were expressed as fusion proteins with the glutathione S-transferase and then used in immunoblotting experiments to analyze sera from patients with autoimmune diseases (chronic active hepatitis, SLE, rheumatoid arthritis, and polymyalgia rheumatica) and from healthy subjects. At a 1:1000 dilution, none of the control sera recognized any of the recombinant polypeptides. Conversely, reactive sera were present in all groups of patients. The ability to recognize a protein domain seemed to differ with the pathology. Most chronic active hepatitis sera were reactive to two or more lamin domains and reacting SLE sera always gave positive signals to coil 2 and/or coil 1B. Coil 2 was preferentially recognized by rheumatoid arthritis sera. Polymyalgia rheumatica sera differed from all of the others because of their low reactivity to the rod domain and preference for the C terminus, a lamin-specific domain.

Autoantibodies to human nuclear lamin B2 protein. Epitope specificity in different autoimmune diseases

The nuclear lamina of mammalian cells consists of three major proteins, lamins A, C, and B, and a fourth minor protein, lamin B2. Lamins belong to the family of intermediate filaments and are highly similar both in structure and primary sequence. They are organized in three well-defined domains: 1) a central alpha-helical rod, which is a secondary structure shared by all types of intermediate filaments, formed by three alpha-helices (coils 1A, 1B, and 2) and surrounded by 2) an amino-terminal head and 3) a carboxyl-terminal tail. Autoantibodies toward major lamin have been described previously in sera from patients with different autoimmune diseases. We chose an epitope mapping approach to further characterize the autoimmune response to nuclear lamin. Different lamin B2 domains were expressed as fusion proteins with the glutathione S-transferase and then used in immunoblotting experiments to analyze sera from patients with autoimmune diseases (chronic active hepatitis, SLE, rheumatoid arthritis, and polymyalgia rheumatica) and from healthy subjects. At a 1:1000 dilution, none of the control sera recognized any of the recombinant polypeptides. Conversely, reactive sera were present in all groups of patients. The ability to recognize a protein domain seemed to differ with the pathology. Most chronic active hepatitis sera were reactive to two or more lamin domains and reacting SLE sera always gave positive signals to coil 2 and/or coil 1B. Coil 2 was preferentially recognized by rheumatoid arthritis sera. Polymyalgia rheumatica sera differed from all of the others because of their low reactivity to the rod domain and preference for the C terminus, a lamin-specific domain.

Long term treatment of polymyalgia rheumatica with deflazacort

OBJECTIVES

To evaluate the long term efficacy and tolerability of deflazacort, a corticosteroid reputed to have only minor side effects, in the treatment of polymyalgia rheumatica (PMR).

METHODS

In a prospective open study, deflazacort was administered at an average initial dose of 21.8 mg/day for a mean period of 19 months in 40 patients with PMR.

RESULTS

A highly significant improvement of clinical and laboratory parameters occurred one month after therapy onset. This improvement persisted for the whole study period. Laboratory parameters of tolerability did not change during the study. Mild to moderate steroid-related side effects occurred in 57.9% of the patients.

CONCLUSIONS

Deflazacort is effective in the treatment of PMR. Its long term safety profile may be superior to that of other corticosteroids.

Anticardiolipin antibodies in pediatric systemic lupus erythematosus

OBJECTIVE

To investigate the prevalence and the clinical significance of anticardiolipin antibodies (ACLs) in a group of children with systemic lupus erythematosus (SLE).

DESIGN

Cross-sectional and longitudinal study.

SETTING

Pediatric Clinic, University of Pavia, Italy.

PARTICIPANTS

Thirty children (aged 4.9 to 16.5 years) with SLE.

MEASUREMENTS AND MAIN RESULTS

Twenty-six (87%) of the 30 patients were initially positive for either IgG or IgM ACLs; 24 (80%) of 30 had IgG ACLs, and 15 (50%) of 30 had IgM ACLs. The cross-sectional analysis showed a trend for IgG ACLs to be positively associated with autoimmune cytopenia and negatively associated with renal disease. The levels of ACLs, particularly of the IgG isotype, tended to correlate with SLE activity as expressed by the complement fraction C3, the erythrocyte sedimentation rate, or the SLE Activity Measure, but not by the SLE Disease Activity Index or the anti-DNA antibodies. Serial determinations of ACL levels in 20 patients revealed frequent fluctuations. High levels of IgG ACLs (> 50 arbitrary units) were observed in nine patients; all nine had active disease and eight had one or more clinical features that have been previously associated with antiphospholipid antibodies: neuropsychiatric manifestations in six patients, autoimmune cytopenia in two patients, and avascular necrosis of bone in one patient. Only one patient experienced an overt episode of vascular thrombosis; IgG ACLs were positive at a medium level 6 months before the thrombotic event, but their level was unchanged when the thrombosis was discovered; the lupus anticoagulant test was positive at time of the thrombosis.

CONCLUSIONS

Our results show that in pediatric SLE, ACLs are frequently found, high levels of IgG ACLs are often associated with central nervous system involvement, and ACLs have a low predictive value in the development of vascular thrombosis.

Frequency and clinical significance of anti-RNP antibodies in Italian SLE patients

The frequency and clinical significance of anti-RNP antibodies in patients with systemic lupus erythematosus (SLE) are still a matter of debate. In this study we report our experience with a series of 123 unselected Italian patients (93 adults and 30 children) suffering from SLE according to the ARA criteria. Anti-RNP were detected by counterimmunoelectrophoresis in 25 patients (20%), 19 of whom did not show other antibodies to extractable antigens (isolated RNP). Our study shows a striking association between anti-RNP and arthritis as well as between anti-RNP and Raynaud's phenomenon. In addition, we found an association between anti-RNP and lack of renal involvement. This association was limited to those patients with isolated RNP and was independent of the presence of anti-dsDNA antibodies. These data were confirmed by a 50 month follow-up study.

Is Tolosa-Hunt syndrome a limited form of Wegener's granulomatosis? Report of two cases with anti-neutrophil cytoplasmic antibodies

Two patients with recurrent painful ophthalmoplegia due to granulomatous involvement of the intracavernous sinus (Tolosa-Hunt syndrome) had circulating anti-neutrophil cytoplasmic antibodies with a granular cytoplasmic immunofluorescence pattern during a flare-up of the disease. The presence of these antibodies suggests that Tolosa-Hunt syndrome might be regarded as a localized form of Wegener's granulomatosis.

Severe retinopathy in systemic lupus erythematosus associated with IgG anticardiolipin antibodies

A six-year-old boy with systemic lupus erythematosus developed insidiously a monolateral serous retinal detachment leading to severe visual loss. Serial determinations of anticardiolipin antibodies showed the presence of IgG anticardiolipin antibodies only at the time of ocular involvement. This case underlines the need for regular ophthalmologic evaluation in children with active systemic lupus erythematosus and supports the previous hypothesis of a relationship between antiphospholipid antibodies and retinal involvement in systemic lupus erythematosus.

Sex hormones and bone metabolism in postmenopausal rheumatoid arthritis treated with two different glucocorticoids

To investigate the effect of low doses of 2 different glucocorticoids on bone mass, sex hormone status and bone metabolic indices, a study was undertaken in 16 postmenopausal women with rheumatoid arthritis (RA) receiving < 15 mg/day of deflazacort and in 16 patients with RA matched for age, years postmenopause and disease duration, receiving < 10 mg/day of prednisone. Sixteen healthy postmenopausal women and 16 nonsteroid treated patients with RA were also studied as control groups. Vertebral bone density (vBMD) was lower (mean +/- SD: 0.65 +/- 0.07 vs 0.73 +/- 0.09 g/cm2; p < 0.02) in prednisone treated patients than in deflazacort treated patients, whose vBMD values were similar to those of nonsteroid treated RA. No significant difference was found as for radial bone mineral content. Circulating levels of estradiol, dehydroepiandrosterone sulfate, androstenedione and progesterone were low in all patient groups with RA when compared with healthy controls. The prednisone treated patients showed significantly lower values of all sex hormones with respect to deflazacort treated patients. Osteocalcin values were also lower (3.0 +/- 1.4 vs 3.9 +/- 1.6 ng/ml; p < 0.05) in prednisone treated patients with respect to deflazacort treated group. Glucocorticoid treated patients showed a direct correlation (r2 = 0.39) between vBMD and plasma estradiol levels, while no correlation was found with osteocalcin values. In conclusion, our postmenopausal patients with RA treated with low dose prednisone had reduced levels of sex hormones and osteocalcin and reduced vertebral bone mass. Comparable doses of deflazacort showed only a mild inhibitory effect on sex hormones and osteocalcin, and did not show any detectable effect on bone mass.

Antiphospholipid antibody associated thrombosis in juvenile chronic arthritis

A child with systemic onset juvenile chronic arthritis (JCA) who developed a bilateral femuropopliteal vein thrombosis after plaster immobilisation following a tibial fracture is described. When the thrombosis was diagnosed, antiphospholipid antibodies detected either as lupus anticoagulant and anticardiolipin antibodies were found. This suggests that short term prophylatic antithrombotic treatment should be considered in antiphospholipid antibody positive JCA patients who require immobilisation after fractures of demineralised bones.

Antibodies to hn-RNP protein A1 in systemic lupus erythematosus: clinical association with Raynaud's phenomenon and esophageal dysmotility

Antibodies to recombinant hn-RNP protein A1 were found by ELISA in sera from 26 out of 67 unselected patients with systemic lupus erythematosus. A higher number of anti-A1 positive patients had Raynaud's phenomenon (50% vs 7%) and esophageal dysmotility (42% vs 5%) than the anti-A1 negative patients. All 8 patients with both Raynaud's phenomenon and esophageal dysmotility had a positive anti-A1 assay. No association was found with other clinical findings, nor with disease activity and treatment regimes. Anti-A1 antibodies did not correlate with anti-RNP and anti-Sm antibodies, which were present in 30% and 12% of the anti-A1 positive cases and in 22% and 7% of the anti-A1 negative cases, respectively. Our results indicate that antibodies to hn-RNP protein A1 may be associated with a subset of SLE patients with clinical features overlapping those of progressive systemic sclerosis and quite distinct from the group identified by anti-RNP antibodies.

Prevalence of anticardiolipin antibodies in juvenile chronic arthritis

The prevalence of anticardiolipin antibodies was evaluated in 70 children with juvenile chronic arthritis (JCA), in 25 adult patients with rheumatoid arthritis, in 42 healthy children and in 40 adult controls. Thirty seven (53%) patients with JCA were positive for IgG or IgM anticardiolipin antibodies, or both, and 30 (43%) for IgG anticardiolipin antibodies. In contrast, only seven (28%) adult patients with rheumatoid arthritis presented anticardiolipin antibodies, which were of IgG class in four (16%) cases. IgG anticardiolipin antibodies were negative in all control subjects while IgM anticardiolipin antibodies were detected in two (5%) children and in four (10%) adult controls. No correlations were found in patients with JCA between the presence or titres of anticardiolipin antibodies and various clinical or laboratory variables. No patient with anticardiolipin antibodies showed any feature of the anticardiolipin syndrome.

Purpura fulminans as clinical manifestation of atypical SLE with antiphospholipid antibodies: a case report

Purpura Fulminans and DIC were the main clinical manifestations of the antiphospholipid syndrome observed in a 62-year-old man. The patient was well until 44 years of age when he began to suffer from recurrent thrombophlebitis, without other symptoms suggestive of immune disease. At the time of hospital admission the pt. appeared acutely ill, showing high fever, severe anemia, massive urinary blood loss, multiple purpuric patches evolving to hemorrhagic bullae and gangrene rapidly spreading over about 30% of the total body area. No signs of neurological involvement or of visceral thrombotic occlusions were present. Clotting tests were consistent with a diagnosis of DIC, further confirmed by skin biopsy showing the presence of thrombi in dermal arterioles. The autoantibody research was positive as follows: Waaler-Rose 1:40, Anti-DNA 1:80; ANF 1:640, aCA IgG 100 GPL. LA was diagnosed according to standard criteria: prolonged KCT and RVVT not corrected by a mixture of normal plasma and abnormal TTI. Plasma exchange in association with heparin and prednisone was effective in arresting the progression of the skin lesion; nevertheless the patient died ten days after hospital admission for sepsi and acute renal failure.

A seasonal pattern in the onset of polymyalgia rheumatica

The seasonal distribution in the onset of polymyalgia rheumatica (PMR) was determined in 58 patients with the disease and compared with that in 44 patients affected by rheumatoid arthritis of elderly onset (EORA). Thirty six (62%) cases of PMR developed during May to August; by contrast, only 14 (31%) cases of EORA developed in the same months, this latter disease failing to show any seasonal clustering. The monthly distribution of PMR correlated with outside temperature and hours of sunshine. These data suggest that PMR might be triggered by such factors as actinic damage of superficial vessels or infective agents with a seasonal cycle. Finally, the summer clustering of PMR may be helpful in the differential diagnosis from EORA.

Autoantibodies in juvenile dermatomyositis

Fourteen patients with juvenile dermatomyositis (JDM) have been investigated for the presence of several serum autoantibodies: antinuclear (ANA), anti-single-stranded and double-stranded DNA, anti-histones, anti-Sm, anti-ribonucleoprotein, anti-SSA/SSB, anti-PM-1, anti-Jo-1, anti-mitochondrial, anti-smooth muscle, anti-gastric parietal cells, anti-cardiolipin (ACA) antibodies and rheumatoid factor. Patients were negative for all autoantibodies except for ANA and ACA. ANA were detected in 50% of the patients when tested on rat liver, but the percentage of positivity rose to 86% when HEp-2 cells were used as substrate. This finding suggests that HEp-2 cells represent a more sensitive substrate than rat liver for the detection of ANA in JDM. Three patients were positive for ACA; two of these presented vascular complications, thus suggesting a possible relationship between ACA and vascular involvement in JDM.

Antibodies from patients with rheumatoid arthritis and systemic lupus erythematosus recognize different epitopes of a single heterogeneous nuclear RNP core protein. Possible role of cross-reacting antikeratin antibodies

Antibodies to recombinant heterogeneous nuclear RNP core protein A1 were detected in sera from 27 of 58 patients with rheumatoid arthritis (RA) and from 7 of 31 patients with systemic lupus erythematosus, by immunoblotting and enzyme-linked immunosorbent assay. Protein A1 consists of 2 distinct domains: The N-terminal sequence is identical to a single-stranded DNA binding protein termed UP1, and the C-terminal domain shows a partial homology with keratin. All 7 A1-positive systemic lupus erythematosus sera reacted with UP1, whereas 9 of the 27 A1-positive RA sera did not. In RA, anti-A1 activity was significantly associated with antikeratin antibodies (AKA); these antibodies were present in 23 of 27 A1-positive sera and 10 of 31 A1-negative sera (P less than 0.01). Immunoabsorption with recombinant protein A1 resulted in a significant reduction of AKA titers in 6 of 10 RA sera tested, suggesting that AKA from RA patients may cross-react with the C-terminal portion of the heterogeneous nuclear RNP protein A1.

Anticardiolipin syndrome in childhood: a report of two cases

We describe two children with an otherwise unexplained deep vein thrombosis associated with high titer anticardiolipin antibodies (ACA) of the IgG class and circulating lupus anticoagulant (LAC). One of these patients had persistent proteinuria but neither had systemic lupus erythematosus. Our observation suggests that ACA and LAC assays should be performed in children with thromboembolic disease even when no underlying autoimmune disease can be found.