Increased prevalence of joint manifestations in patients with recurrent aphthous stomatitis (RAS)

OBJECTIVE

To characterize the systemic manifestations and joint disease in patents with recurrent aphthous stomatitis (RAS).

METHODS

The presence and features of extra-oral manifestations were determined by a rheumatologist, who examined and interviewed 64 patients, referred during 1993 to the oral medicine clinic for treatment of RAS. Controls were 65 medical staff members of a military clinic associated with the hospital.

RESULTS

Based on the rheumatologist's findings and published criteria, the patients were diagnosed as suffering from RAS alone (24 patients), Reiter's syndrome (8), Behçet disease (8), familial Mediterranean fever (1), or RAS with undiagnosable extra oral manifestations (23). Thirteen patients in the last group had joint disease (p < 0.01 compared to the controls), characterized by recurrent mono- or oligoarthritis/arthralgia of short duration, affecting mostly the large joints. Conjunctivitis, pustular rash, lower back pain and urethritis/cervicitis were also common in RAS patients, but only the latter was significantly more frequent in RAS patients than in controls (p < 0.02).

CONCLUSION

These findings suggest that patients with RAS have an increased frequency of a palindromic type joint disease.

[Research for basic and clinical aspects of Behcet's disease--recent advance and future--]

To elucidate the role played by HLA-B51 in the neutrophil hyperfunction of Behcet's disease, we determined the superoxide production by purified peripheral blood neutrophils from Behcet's disease patients, from HLA-B51 positive healthy individuals, and from HLA-B51 transgenic mice. As a result, a significant correlation between the neutrophil hyperfunction and the possession of HLA-B51 phenotype, regardless of the presence of the disease, was observed in humans. FMLP-stimulated neutrophils (without in vitro priming) from HLA-B51 transgenic mice, but not those from HLA-B35 transgenic mice or from nontransgenic mice, produced substantial amounts of superoxide. The HLA-B51 molecule itself may thus be responsible, at least in part, for neutrophil hyperfunction in Behcet's disease. CD4+ alphabeta T cells in this disease proliferated vigorously in response to specific peptide derived from human heat shock protein (HSP)-60; however, CD4+ alphabeta T cells from normal subjects or patients with rheumatoid arthritis did not. This peptide has the amino acid sequence 336-351 of human HSP60, which is similar, but not identical to specific peptide of mycobacterial HSP-65. To clarify whether the peptide stimulates patients' T cells as a polyclonal activator, a specific antigen or superantigen-like substance, we have also analyzed TCR usage of responsive T cells by means of TCR Vbeta subfamily-specific mAbs and PCR single strand conformation polymorphism-based technique. We found that T cells with specific TCR Vbeta subfamilies proliferated and increased in number in response to the peptide by an antigen-specific fashion. The result of recurrent exposure to the HSP may break the tolerance to self HSP, and provoke T cell responses to self and microbial HSP. Such T cells may produce Th1-like proinflammatory cytokines and lead to tissue injury possibly via delayed-type hypersensitivity reaction, macrophage activation, and activation and/or recruitment of neutrophils. Our data shed a new light on the autoimmune nature of Behcet's disease; a novel multistep molecular mimicry mechanism may induce and/or exacerbate Behcet's disease by bacterial antigens that activate T cells previously educated by self-peptide(s) of HSP. This would lead to positive selection of autoreactive T cells in this disease.

Cytokines in Behçet's disease

OBJECTIVE

Cytokines take place in immunologic and inflammatory reactions. The aim of this study was to describe the roles of various cytokines in the pathogenesis of Behçet's disease (BD).

METHODS

Serum levels of interleukin-1 beta (IL-1 beta), interleukin-2 (IL-2), soluble IL-2 receptor (sIL-2R), interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-alpha) were studied in 24 patients with active BD and 15 healthy adults as controls, by ELISA technique. Patients were separated into 2 groups according to the number of active organ systems (Group I: < 3 vs Group II: > or = 3).

RESULTS

sIL-2R and age adjusted TNF-alpha levels were higher in patients with BD compared to controls (p = 0.004 and p = 0.002, respectively). But the median concentrations of Group I and Group II were not different. Serum levels of IL-1 beta, IL-2 and IL-6 were similar to the control group.

CONCLUSION

High serum levels of sIL-2R and TNF-alpha indicate activation of the immune system in BD. But this finding may not be useful as a marker of disease activity.

[Cytolysosomes in red blood cells of patients with Behçet's disease at the exacerbation stage]

Peripheral erythrocytes of 5 patients with Behet's disease, not receiving systemic treatment, at the exacerbation stage, and those of 3 healthy controls were investigated with a transmission electron microscope. More than 100 cells were examined per subject. Cytolysosomes (autophagic vacuoles) were frequently observed in cells of the patients. The average frequency of appearance of cytolysosomes was 5.4 +/- 1.5% (mean +/- deviation) in erythrocytes of the 5 patients, and 0.5 +/- 0.4% in those of the 3 control subjects. The difference was statistically significant (p < 0.026). These results suggest that cytolysosomes of erythrocytes may reflect abnormal production or removal involved in the pathophysiology of Behçet's disease.

Behçet's disease induced by interferon therapy for chronic myelogenous leukemia

A 59-year-old Japanese woman, diagnosed with mixed connective tissue disease (MCTD) and chronic myelogenous leukemia (CML), developed several characteristic features of Behçet's disease (BD) after receiving alpha-interferon (IFN-alpha). She displayed recurrent oral aphtha, genital ulceration, erythema nodosum at the bilateral arm, and low grade fever. The skin of the femur where the IFN-alpha was injected showed modular acneiform changes. Skin biopsy revealed perivascular infiltration. The symptoms compatible with BD improved after discontinuation of IFN-alpha and the introduction of prednisolone and azathioprine. This is the first description of BD induced by IFN-alpha.

The role of ambiental agents in Behçet's disease

OBJECTIVE

To evaluate the potential role of environmental agents in the etiopathogenesis of Behçet's disease.

METHODS

Twenty-eight Behçet's disease patients and 56 controls were recruited prospectively from the outpatient rheumatic disease clinic at the Escola Paulista de Medicina between July 1991 and July 1992. Behçet's disease was diagnosed using one of the accepted sets of criteria (Japanese Committee, International Committee, O'Duffy, Mason & Barnes, and James). The control patients, who had other rheumatic diseases, were matched on age and sex with the Behçet's disease patients. To investigate environmental factors, a standardized questionnaire was administered to each subject during an interview. Clinical and laboratory investigations were performed in each subject according to a predefined protocol.

RESULTS

Analysis using the Chi-square test or Fisher's exact test (Cochran's restriction) disclosed significant associations between Behçet's disease and a history of herpes simplex virus type 1 infection or streptococcal infection.

CONCLUSIONS

Despite the small sample size, our data strongly support a role of infectious agents in the etiopathogenesis of Behçet's disease. Further studies in larger patient populations are needed to confirm our results.

[Testicular localization of systemic diseases]

Acute orchitis or a mass in testis usually evokes a neoplasm, a torsion or infectious disease for the clinician. Rarely, a systemic disease is involved. Nevertheless, testicular involvement occurs during vasculitis, Behçet or granulomatous diseases, but is uncommonly the first manifestation. Histologic changes after biopsy or orchiectomy usually give the diagnosis. Testicular localization of systemic disease does not change the general treatment.

A comparison of sarcoidosis and Behçet's disease

There are several diseases which present with both ocular and thoracic disease (Table I). Behçet's disease (BD) may be confused with sarcoidosis because they are both multisystem inflammatory disorders presenting with uveitis, polyarthritis, meningitis, cardiovascular disease, erythema nodosum and other cutaneous lesions, and abnormal chest radiographs. The aetiology of both disorders continues to elude us. Hopefully, a careful study of the one may shed light and knowledge on the other.

Pathogenesis of mucocutaneous lesions in Behçet's disease

Behçet's disease (BD) is characterized by recurrent oral aphthae, skin lesions, eye lesions, and genital ulceration. To determine the pathogenesis of BD, we performed histological and immunohistochemical studies of these mucocutaneous lesions, an assay of neutrophil activity, and HLA typing. Dense dermal or subcutaneous infiltrations of polymorphonuclear cells (PMN) without leukocytoclastic vasculitis were found in 28 of 57 lesions. Immunohistochemically, deposits of C3 on the vessels were found in 12 of 31 lesions. Deposits of immunoglobulin were not found except for one of IgM. C3 deposits and PMN infiltrations were significantly related (p < 0.05). PMN activity by polarization was enhanced; however, the results did not show a significant relationship with the PMN infiltrations or the C3 deposits. The incidence of HLA-B51 was significantly high in BD, but no significant relationship was found between HLA-B51 and the results of other examinations. These results suggest that the pathogenesis of BD lesions differs from that of collagen diseases and that C3 deposits on the vessels may play an important role in the development of mucocutaneous lesions where PMN have mainly infiltrated.

Identification of heat shock proteins binding to an immunodominant uveitopathogenic peptide of IRBP

Intracellular binding proteins have been identified and isolated from B cells by their ability to bind to the synthetic peptide (1169-1191), the major immunodominant epitope of bovine interphotoreceptor retinoid-binding protein (IRBP) coupled to cyanogen bromide activated Sepharose 4B. After SDS-PAGE, two discrete protein bands of approximately 72 and 74 kDa, were found to be present in B cells of naive Lewis rats as well as in EBV transformed B cells from a human patient with ocular Behçet's disease. Enhanced expression of these peptide-binding proteins was achieved by incubating the cells with Lipopolysaccharide (LPS) from S. typhimurium. The approximately 72 and 74 kDa peptide-binding proteins reacted in western blot with monoclonal antibodies specific for both constitutively expressed and inducible 72/74 kDa hsp 70 proteins. The demonstration that these proteins bind to the immunodominant epitope of IRBP indicates that they may play a role in the processing and presentation of antigens by antigen-presenting cell (APC).

Behçet's disease

The International Study Group's diagnostic criteria for Behçet's disease are gaining acceptance and may be further refined before the decade is over. Previously neglected clinical features of the disease, especially arterial aneurysms and phlebitis, are increasingly reported. Each poses a dilemma in the choice of treatment, which ranges from anticoagulant to immunosuppressant regimens, old and new. T-lymphocyte abnormalities, both in subpopulation and function, suggest ongoing presentation of an unknown antigen. Research on the role of HLA-B51, a split of B5, is moving centromeric to it in pursuit of a better disease marker. The choice of immunosuppressive therapy in severe disease such as uveitis and arteritis is between alkylating agents and agents that inhibit interleukin-2 production.

Antibodies to endothelial cells in patients with Behçet's disease

Autoantibodies that bind to endothelial cells have been identified in patients with several forms of vasculitis. Behçet's disease--a multisystem inflammatory disorder of unknown etiology--is associated with thrombosis in addition to systemic manifestations resulting from small and large vessel vasculitis. We studied 72 Turkish patients (33 female, 39 male) with Behçet's disease in order to investigate the prevalence of antiendothelial cell antibodies (AECA) and to examine their possible relationship with clinical and laboratory features of the illness. Sera from 30 healthy Turkish people were used as controls. Human umbilical vein endothelial cells were cultured and used unfixed in a cellular ELISA to detect AECA. IgG and/or IgM AECA were found in 13 (18.1%) patients but not in healthy controls. Antiendothelial cell antibodies did not induce complement-mediated cytotoxicity as assessed by 51Cr release assay and the binding was not due to immune complexes. The prevalences of acute thrombotic events and retinal vasculitis at the time of the AECA assay among patients with AECA were significantly higher than those in patients without AECA. Laboratory parameters of active disease were higher in patients with AECA. There was no correlation between other clinical and laboratory features of Behçet's disease and AECA. Anticardiolipin and antineutrophil cytoplasmic antibodies were negative in our series, excluding a possibility of cross-reaction with AECA. Our results suggest a possible role of AECA in association with thrombosis and vasculitis in patients with Behçet's disease.