Management of Behçet disease: a systematic literature review for the European League Against Rheumatism evidence-based recommendations for the management of Behçet disease.

OBJECTIVES: To present and analyse the literature sources regarding the management of Behçet disease (BD) identified during the systematic literature research, which formed the basis for the European League Against Rheumatism (EULAR) evidence-based recommendations for the management of BD. METHODS: Problem areas and related keywords regarding the management of BD were determined by the multidisciplinary expert committee commissioned by EULAR for developing the recommendations. A systematic literature research was performed using MedLine and Cochrane Library resources through to December 2006. Meta-analyses, systematic reviews, randomised controlled trials (RCTs), open studies, observational studies, case control studies and case series' involving > or = 5 patients were included. For each intervention the effect size and number needed to treat were calculated for efficacy. Odds ratios and numbers needed to harm were calculated for safety issues of different treatment modalities where possible. RESULTS: The literature research yielded 137 articles that met the inclusion criteria; 20 of these were RCTs. There was good evidence supporting the use of azathioprine and cyclosporin A in eye involvement and interferon (IFN)alpha in mucocutaneous involvement. There were no RCTs with IFNalpha or tumour necrosis factor (TNF)alpha antagonists in eye involvement. Similarly controlled data for the management of vascular, gastrointestinal and neurological involvement is lacking. CONCLUSION: Properly designed, controlled studies (new and confirmatory) are still needed to guide us in managing BD.

Treating ocular toxoplasmosis: current evidence.

The current treatment of ocular toxoplasmosis is controversial. The mainstay of treatment has been pyrimethamine and sulphonamides with or without systemic corticosteroids, but the actual evidence that antibiotics have a beneficial effect in recurrent toxoplasmic retinochoroiditis is unsupported by randomised placebo controlled trials. Thus far there have only been three studies looking at the efficacy of antibiotic treatment, all of which were methodologically weak and two of which were perfomed more than 30 years ago. All studies reported adverse effects from treatment. There is an urgent need for further randomised, double blind, placebo controlled studies for lesions in all parts of the retina and to test the efficacy of adjunctive corticosteroid treatment.

Immunity and Toxoplasma retinochoroiditis.

Toxoplasma infection accounts for up to 50% of all cases of posterior uveitis worldwide. In this review the control of Toxoplasma infection generally, and specific in the eye, by the immune system is discussed.

EULAR recommendations for the management of Behçet disease.

OBJECTIVES: To develop evidence-based European League Against Rheumatism (EULAR) recommendations for the management of Behçet disease (BD) supplemented where necessary by expert opinion. METHODS: The multidisciplinary expert committee, a task force of the EULAR Standing Committee for Clinical Affairs (ESCCA), consisted of nine rheumatologists (one who was also a clinical epidemiologist and one also a Rehabilitation Medicine doctor), three ophthalmologists, one internist, one dermatologist and one neurologist, representing six European countries plus Tunisia and Korea. A patient representative was also present. Problem areas and related keywords for systematic literature research were identified. Systematic literature research was performed using Medline and the Cochrane Library databases from 1966 through to December 2006. A total of 40 initial statements were generated based on the systematic literature research. These yielded the final recommendations developed from two blind Delphi rounds of voting. RESULTS: Nine recommendations were developed for the management of different aspects of BD. The strength of each recommendation was determined by the level of evidence and the experts' opinions. The level of agreement for each recommendation was determined using a visual analogue scale for the whole committee and for each individual aspect by the subgroups, who consider themselves experts in that field of BD. There was excellent concordance between the level of agreement of the whole group and the "experts in the field". CONCLUSION: Recommendations related to the eye, skin-mucosa disease and arthritis are mainly evidence based, but recommendations on vascular disease, neurological and gastrointestinal involvement are based largely on expert opinion and uncontrolled evidence from open trials and observational studies. The need for further properly designed controlled clinical trials is apparent.

Serum cytokine profiles in Behçet's disease: is there a role for IL-15 in pathogenesis?

OBJECTIVES: Behçet's disease (BD) is a multisystem inflammatory disease characterised by recurrent orogenital ulceration, ocular inflammation and skin lesions whose aetiology is currently unknown. We hypothesized that levels of cytokines in the serum might provide either diagnostic or activity markers for the disease. METHODS: Levels of 10 cytokines were analysed in a multiplex bead analysis system as well as IL-15 by ELISA, in 79 serum samples from 52 patients with BD. The same cytokines were also measured in serum samples from 20 patients with recurrent aphthous stomatitis (RAS), as disease controls, and 15 healthy volunteers. The results were correlated with disease activity and current drug therapy. RESULTS: CXCL8 and TNF were the most abundant cytokines and were significantly raised compared to both patients with RAS and healthy controls. IL-15 was present in all samples and was significantly raised in both patients with BD and RAS compared to healthy controls. By comparison, cytokines associated with an adaptive immune response such as IFNgamma and IL-2 were found in few samples, while IL-4 and IL-10 were not detected in any sample. Levels of cytokines correlated with each other suggesting a response to the same stimulus, however, there was no association with either disease activity or treatment. CONCLUSION: Cytokines related to activity of the innate immune response were most prominent in this study and showed good correlation with each other. In particular, it was shown that IL-15 was raised in BD. However, there was no pattern of cytokine expression relating to disease activity or treatment.

Low-dose intra-venous cyclophosphamide therapy in a patient with neurological complications of Behçet's disease.

Behçet's disease (BD) is a chronic relapsing-remitting inflammatory disorder of unknown origin, affecting multiple organs. Neurological involvement is one of the most devastating manifestations of BD and may be fatal. We report a 36-year-old woman with neuro-Behçet who was treated with low-dose pulse cyclophosphamide (St. Thomas' protocol) and methylprednisolone, with almost complete clinical remission.

Expression analysis of immune response genes of Müller cells infected with Toxoplasma gondii.

PURPOSE: To investigate changes in immune response genes following Toxoplasma gondii infection of Müller cells. METHODS: Human Müller cells were infected or mock infected with two strains of T. gondii (RH and Prugniaud). RNA and supernatants were collected from infected and uninfected cells at 2 and 24 h. RNA from the two time points were compared using a custom made DNA microarray. Real time PCR or human cytokine antibody array was used to confirm up-regulation of immune molecules. RESULTS: Gene expression in infected cells showed up-regulation of CCL2, IL-6, CXCL8, and CXCL2. CCL2 and CXCL2 gene expression was confirmed by real time PCR. IL-6 and CXCL8 protein production was confirmed by a cytokine antibody array. IL-4 production was observed by cytokine antibody array but not by DNA microarray. In contrast, infection with T. gondii did not induce interferon-gamma (IFNgamma) and IL-12 expression, molecules conventionally associated with the inter-conversion of tachyzoite to bradyzoite. CONCLUSION: These results indicate that while in vitro infected Müller cells may be capable of inducing an immune response by attracting blood-borne leucocytes, they do not appear able to directly control the proliferation of T. gondii.

Toxoplasmic retinochoroiditis presenting in childhood: clinical findings in a UK survey.

AIM: To compare the clinical findings in children with symptomatic toxoplasmic ocular lesions attributable to infection acquired before or after birth. METHODS: Cases were prospectively ascertained for 24 months through national surveillance units and reference laboratories in the British Isles. Age and presenting symptoms, site of lesion and visual impairment in children who were classified as acquiring infection either before or after birth on the basis of clinical and serological findings were compared. RESULTS: 31 children had toxoplasmic retinochoroiditis, 15 had congenital infection and all but three of these presented before the age of 4 years. The remaining 16 children acquired toxoplasmosis postnatally, and 14 of 16 presented after the age of 10 years. A further four children had retinochoroiditis due to other causes. The presence of bilateral, multiple or posterior pole lesions did not distinguish between the two groups, but most children (16/19; 84%) presenting with acute ocular symptoms had postnatally acquired infection. Unilateral visual impairment (Snellen < or =6/18) was equally prevalent in the two groups (4/9 before birth v 7/16 after birth; p>0.5). Only two children had bilateral visual impairment, both of whom had congenital infection. No child was blind. CONCLUSIONS: About 50% of children with ocular lesions due to toxoplasmosis had postnatal infection. Retinochoroidal lesions due to infection before and after birth were indistinguishable. The prognosis for bilateral visual function was good, regardless of when infection was acquired.

A low balance between microparticles expressing tissue factor pathway inhibitor and tissue factor is associated with thrombosis in Behçet's Syndrome.

Thrombosis is common in Behçet's Syndrome (BS), and there is a need for better biomarkers for risk assessment. As microparticles expressing Tissue Factor (TF) can contribute to thrombosis in preclinical models, we investigated whether plasma microparticles expressing Tissue Factor (TF) are increased in BS. We compared blood plasma from 72 healthy controls with that from 88 BS patients (21 with a history of thrombosis (Th+) and 67 without (Th-). Using flow cytometry, we found that the total plasma MP numbers were increased in BS compared to HC, as were MPs expressing TF and Tissue Factor Pathway Inhibitor (TFPI) (all p < 0.0001). Amongst BS patients, the Th+ group had increased total and TF positive MP numbers (both p ≤ 0.0002) compared to the Th- group, but had a lower proportion of TFPI positive MPs (p < 0.05). Consequently, the ratio of TFPI positive to TF positive MP counts (TFPI/TF) was significantly lower in Th+ versus Th- BS patients (p = 0.0002), and no patient with a TFPI/TF MP ratio >0.7 had a history of clinical thrombosis. We conclude that TF-expressing MP are increased in BS and that an imbalance between microparticulate TF and TFPI may predispose to thrombosis.

The effect of Toxoplasma gondii infection on expression of chemokines by rat retinal vascular endothelial cells.

Cells infected by Toxoplasma gondii undergo up-regulation of proinflammatory cytokines, organelle redistribution, and protection from apoptosis. During infection in man, the parasite encysts within the retina, a process that results in retinochoroiditis which can lead to permanent loss of sight. The reasons for the parasite to infect retinal tissue and the mechanisms by which it encysts are not clearly understood. We studied the effect of infection with T. gondii of retinal vascular endothelial cells using the Clontech Atlastrade mark array system in order to elucidate changes in gene expression. We compared hybridization of RNA to the array from infected and uninfected cells at two time points; 2 and 24 h. Exposure to T. gondii after 2 h resulted in change of expression of approximately 6% of genes on the array, including those involved in cell structure, protein and vesicle trafficking, cell-cycle regulation, transcriptional and translational machinery, and apoptosis. Among the genes involved in the inflammatory response, chemokine genes such as GRO1 (Growth Regulated Oncogene 1), MCP-1 (Monocyte Chemotactic Protein-1), FKN (Fractalkine) and RANTES (Regulated upon Activation, Normal T Cell Expressed and Secreted) were found to be up-regulated and protein production was confirmed by ELISA. However after 24 h of infection, GRO1, MCP-1 and FKN were down-regulated, confirmed by RT-PCR. Thus, invasion of retinal vascular endothelium (RVE) cells by T. gondii leads to the production of chemokines important in directing the traffic of inflammatory cells to the infected area.

The visual field in toxoplasmic retinochoroiditis.

AIMS: To document loss of central field in patients with scars from toxoplasmic retinochoroiditis close to the disc after resolution of disease. METHODS: Patients with a clinical diagnosis of toxoplasmic retinochoroiditis were enrolled from four centres. Automated central visual field testing was performed when their disease had settled and retinal photographs of the lesions were taken. The type of central field defect (whether absolute or relative) and whether it broke out to the periphery were correlated with the size of the retinochoroidal scar and its proximity to the optic nerve head. RESULTS: 69 eyes were enrolled; 16 (26%) were discarded because of poor field performance. Of the 53 remaining eyes, 31 showed absolute defects and 20 relative defects. Scars within one disc diameter of the disc were more likely to be associated with absolute defects breaking out to the periphery. CONCLUSION: The scarring induced by toxoplasmic retinochoroiditis is associated with considerable field loss when it occurs close to the optic nerve head. Current treatment is unlikely to ameliorate this situation. The degree of visual field loss should be an outcome measure for future trials of the efficacy of treatment trials for the disease.

Are cytokine gene polymorphisms associated with outcome in patients with idiopathic intermediate uveitis in the United Kingdom?

BACKGROUND/AIM: Competing levels of cytokines, either locally within the eye or systemically, may influence the eventual outcome of ocular inflammation. Polymorphism in the promoter part of the genes controlling cytokine production may result in either higher or lower production of the relevant cytokine to a given stimulus. The authors hypothesised that such polymorphisms may relate to visual outcome in patients with idiopathic intermediate uveitis. METHODS: DNA was obtained from 125 patients with idiopathic intermediate uveitis and analysed for the interleukin 10 IL-10-1082G/Alpha and IL-10-819C/T, and interferon gamma IFNgamma 874T/A gene polymorphisms. Associations with disease were calculated by both allelic frequency and haplotype analysis, and associations between ocular disease outcomes and the presence of polymorphisms were identified. A bad outcome was defined as loss of vision <6/12 Snellen in both eyes at 5 years from presentation when the eyes were quiet. RESULTS: An initial screen showed that the 874T allele of the IFNgamma gene was more prevalent in patients than controls (chi2= 7.9; p = 0.004 OR 1.7; 95% CI 1.2 to 2.6 (Pc = 0.02), whereas the IL-10-1082/-819 AT haplotype of the interleukin 10 (IL-10) gene was not. Analysis of disease outcome showed an association between IL-10-1082 AA homozygosity and bad outcome (chi2= 13; p = 0.0003). Moreover, the two cytokine polymorphisms taken together showed that up to 75% of patients with a poor visual outcome had the combined IFNgamma 874TA or TT genotype together with the IL-10-1082AA genotype (chi2= 13.2 p = 0.0008 OR 6.4; 95% CI 1.85 to 23.6 Pc = 0.1). CONCLUSION: These results show that disease outcome in intermediate uveitis may be partly determined by a complex interplay between cytokine genes and these results may have implications for future treatment with biological agents that target these cytokines.

Leukocyte trafficking in experimental autoimmune uveitis in vivo.

Leukocyte trafficking from blood into tissue is a fundamental process in immune surveillance and the immune response to stimuli. Experimental autoimmune uveitis (EAU) is an animal model for posterior uveitis and is mediated by T lymphocytes and macrophages that infiltrate the posterior segment of the eye. To analyze leukocyte migration into retinal tissue during the course of EAU, labeled cells were identified in vivo by scanning laser ophthalmoscopy and in retinal flatmounts by confocal microscopy. Adhesion of blood leukocytes to retinal endothelial cells in vivo was significantly raised 48 h before the appearance of clinical disease, and this correlated with the increased expression of CD54 on retinal vessels. Mitogen-activated spleen cells and CD4+ T cells only entered into retinal tissue in animals with clinical disease and not naive recipients. The disease status of the donor animal had no effect on leukocyte trafficking. These results, which identify leukocyte-endothelial cell interactions in vivo, suggest that the activation of the retinal endothelium is a prerequisite to leukocyte adhesion and extravasation into ocular tissue during EAU.

Acute retinal necrosis presenting as central retinal artery occlusion with cilioretinal sparing.

PURPOSE: To report a case of acute retinal necrosis presenting as central retinal artery occlusion with cilioretinal sparing. METHODS: Single interventional case report. The findings of the ophthalmic examination, MRI, blood parameters, biopsy results and clinical course are reported. RESULTS: A forty two year old gentleman reporting sudden loss of sight, ophthalmic examination revealing uveitis, central retinal artery occlusion with cilioretinal sparing and peripheral necrotizing retinitis. CONCLUSIONS: Central retinal artery occlusion can be an early feature of acute retinal necrosis (ARN).

The effect of cytokines on the replication of T. gondii within rat retinal vascular endothelial cells.

Toxoplasma gondii infection of the eye can result in a recurrent necrotising retinochoroiditis (TR) which may lead to a permanent loss of visual acuity. The mechanisms responsible for the control of TR within the retina are unknown. The aim of this study was to examine the effects of cytokines on the replication of T. gondii RH strain tachyzoites within rat retinal vascular endothelial (rRVE) cells. Pretreatment of rRVE with IFNgamma, TNF or IL-1beta resulted in a significant decrease in T. gondii replication from day 2 onwards. There was no significant difference in nitric oxide (NO) production by IFNgamma, TNF or IL-1beta treated rRVE as compared to controls at any time point. By comparison, the addition of L-tryptophan to IFNgamma treated cultures significantly restored T. gondii replication from 48 h post inoculation. Thus, IFNgamma, TNF and IL-1beta can significantly inhibit the replication of T. gondii within rRVE. However, this inhibition appears to be independent of NO production. L-tryptophan catabolism may have a role in IFNgamma mediated inhibition of T. gondii replication in rRVE cells.

Passive administration of antibody against retinal S-antigen induces electroretinographic supernormality.

Electroretinographic supernormality, affecting both the a- and b-waves of the electroretinogram (ERG), occurs consistently before the onset of experimental autoimmune uveoretinitis (EAU) in rabbits and rats. To investigate the possible role of antibody to S-antigen (S-ab) in this phenomenon, affinity-purified polyclonal rat S-ab was injected intravenously into normal rats and administered to isolated rat eyecup preparations by bolus perfusion. In both situations, ERG supernormality was observed. The effect in vivo peaked 90 min after injection, and ERG changes in vitro were observed within 15 sec. The ERG response in vivo and in vitro was dose dependent and was abolished in vivo by pretreatment with cyproheptadine (a serotonin antagonist). The ERG was not affected in either system by a control rat antibody (antiovalbumin) or by murine monoclonal or rabbit polyclonal antibodies to S-antigen. The induction of ERG supernormality in vivo and in vitro by homologous S-ab indicates the operation of species-specific mechanisms both involving and bypassing the blood-retinal barrier and highlights a significant role for humoral autoimmunity in the pathogenesis of S-antigen-induced EAU in the rat.

A new method for studying the selective adherence of blood lymphocytes to the microvasculature of human retina.

PURPOSE: To develop a sensitive and reproducible technique for measuring the adherence of blood lymphocytes to vessel walls exposed in sections of human retina and for examining the role of lymphocyte and vascular adhesion molecules in these events. METHODS: Cryostat sections of human retina were overlaid with blood lymphocytes from healthy subjects, and experimental conditions were sought by which preferential attachment of the cells occurred to blood vessel walls in the retinal sections. Adherent lymphocytes were identified by staining with methyl green-thionine, and transected blood vessels were identified by their structure and by staining of basement membranes with periodic acid-Schiff. The adherence of enriched preparations of CD4+ (T-helper) and CD8+ (T-cytotoxic) lymphocytes, of interleukin-2 (IL-2)-activated cells, and of lymphocytes from patients with ocular Behçet's disease was examined. The distribution of adhesion molecules on retinal vessel walls was determined by immunohistochemistry, and the contribution of leukocyte integrins to lymphocyte binding was studied by blocking experiments with monoclonal antibodies. RESULTS: The optimal selectivity of blood lymphocyte attachment to retinal vessel walls occurred when purified lymphocytes were suspended in culture medium with 10% fetal calf serum and overlaid onto retinal sections for 30 minutes at 23 degrees C with gentle agitation. Under these conditions, 92% of the lymphocytes that adhered to the section were confined to the retinal microvasculature, and CD4+ T cells were more adherent than CD8+ T cells (P < 0.01). Prior exposure of normal lymphocytes to IL-2 enhanced their binding to retinal blood vessels, and lymphocytes from patients with Behçet's disease showed supranormal vascular adherence (P < 0.005). Many transected vessels stained positively for CD31; PECAM (mean 62%), CD54; ICAM-1 (mean 73%), CD62E; E-selectin (mean 35%), CD62P; P-selectin (mean 61%), and CD106; VCAM-1 (mean 42%). However, these vascular adhesion molecules occupied < 20% of the area of the blood vessel walls. Lymphocyte adhesion to the retinal vessels was more dependent on CD29 (the common chain of the beta 1 integrins) expression than either CD11a/CD18 or CD49d. CONCLUSIONS: This technique allows measurements to be made of lymphocyte adherence to vascular and nonvascular structures of retina ex vivo. Extension of this approach to the study of leukocyte adherence to sections of pathologic retina may be of clinical and experimental applicability in understanding mechanisms of retinal inflammation.

Differential effect of Bordetella pertussis on experimental posterior uveitis in the black-hooded Lister rat.

The effect of an additional adjuvant, Bordetella pertussis, on the clinical and histopathologic features of experimental autoimmune uveitis in black-hooded Lister rats was investigated. Disease was induced by a single footpad injection of purified retinal S-antigen in Freund's complete adjuvant. In those animals that did not receive B Pertussis the clinical features were those of a retinal vasculitis with disc edema, periphlebitis, and deep retinal infiltrates. In contrast, animals that received B pertussis developed lesions in the pigment epithelium and choroid. Histopathologic studies disclosed focal photoreceptor necrosis associated with mononuclear cell infiltration in both groups of animals. However, in the group that did not receive B pertussis the disease was predominantly a retinitis associated with perivascular infiltration of retinal vessels, whereas in the group that did receive B pertussis the main feature was a focal choroiditis, with superficial retinal lesions being rarely observed. Retinal photoreceptors were the target tissue in both groups of rats, but the route by which they were damaged was altered from predominantly retinal to choroidal by the addition of Bordetella pertussis as an adjuvant. This change may be ascribed to the ability of B pertussis toxin to sensitize vascular endothelium to local mast cell products, these cells being plentiful around choroidal vessels but absent in the retinal circulation.

Factor V Leiden mutation is associated with ocular involvement in Behçet disease.

PURPOSE: Behçet disease is a systemic disease of young adults characterized by venous occlusion in both the deep venous and retinal circulations. In severe ocular disease, blindness may occur despite immunosuppressive treatment. The most common inherited risk factor for the development of idiopathic venous thrombosis is the presence of the Factor V (FV Leiden) mutation, which confers resistance to activated protein C. The association of FV Leiden with Behçet disease has been reported, but its influence on ocular disease is not known. We therefore investigated the prevalence of this mutation in patients with Behçet disease to determine its contribution to the presence and severity of ocular disease. METHODS: One hundred and six Middle Eastern patients satisfying international criteria, and 120 healthy control subjects without a history of venous thrombosis were included in the study, and patients underwent standard examination by two ophthalmologists with an interest in Behçet disease. Genomic DNA was extracted from peripheral blood leukocytes and screened for the FV Leiden mutation with the polymerase chain reaction method with sequence-specific primers (PCR-SSP). RESULTS: FV Leiden was detected in 19% (23/120) of the control population compared with 27% (29/106) of all patients with Behçet disease (P = .13). However, among patients with Behçet disease who had ocular disease (75/106), the prevalence of FV Leiden was significantly higher (32%) than it was in control subjects (P = .04). Furthermore, ocular patients with Behçet disease in whom retinal occlusive disease was observed (25/75) had the highest expression of FV Leiden (44%). CONCLUSIONS: These data suggest that FV Leiden may be an additional risk factor for the development of ocular disease and, in particular, retinal vaso-occlusion, and it may contribute to the poor visual outcome in these patients.

Experimental posterior uveitis. II. Electroretinographic studies.

Experimental posterior uveitis was induced by the inoculation of retinal S-antigen into black hooded Lister rats. The time course of the disease was monitored by electroretinography (ERG), and the ERG changes were correlated with clinical signs and underlying pathological damage. The ERG became supernormal in the third week after inoculation, with some loss of temporal resolution (lowered ERG flicker fusion frequency), though the disease was not clinically manifest at this time and histological examination was normal. The ERG became subnormal after 21 days as clinical signs of disease began to appear. This subnormality was associated with focal photoreceptor necrosis, the degree of destruction being proportional to the reduction in the ERG. The ERG recovered with resolution of disease in most cases, though return to control values was uncommon. We suggest that the initial supernormal ERG reflects an underlying biochemical change mediated by the action of anti retinal S-antigen antibodies.