Presence of circulation immune complexes in Reiter's syndrome and ankylosing spondylitis

Síndrome de reiter: relato de caso

Relato de um caso de síndrome de Reiter em paciente jovem, do sexo masculino, com lesões dermatológicas típicas e achado positivo para o antígeno do complexo de histocompatibilidade HLA-B27. O quadro surgiu após infecção intestinal por Salmonella enteritidis, evoluindo com melhora após utilização de tetraciclina, prednisona e indometacina. Episódio recidivante foi tratado com metotrexato. É feita uma revisão da literatura, abordando os aspectos clínicos, laboratoriais, etiológicos e fisiopatogênicos dessa síndrome.

Reiter's syndrome and reactive arthritis: a current view

This paper reviews advances in the understanding of the pathogenesis of reactive arthritis that have occurred over the last decade. Inflammatory aseptic joint disease has been linked with prior infection initiated by many different species of microorganisms. The presence of intra-articular bacterial antigens has now been firmly established with the demonstration of bacteria, bacterial fragments, DNA, RNA, and bacterial lipopolysaccharide in joints of patients with reactive arthritis. Chlamydia trachomatis, Salmonella enteritidis, and Shigella flexneri have all been detected in the joint by immunological techniques, although there is still some doubt as to the form in which they reach the joint and whether or not they persist. A number of phlogistic bacterial components could be acting as arthritogens. Negative joint culture results from patients with reactive arthritis make it unlikely that bacteria in the joint are viable, although chlamydial DNA has been shown in the joints of patients with sexually acquired reactive arthritis using the polymerase chain reaction. The use of antimicrobial therapy in the treatment of reactive arthritis is under review; data suggests that long-term antibiotic treatment warrants further study. The role of HLA-B27 in disease pathogenesis is discussed as are possible mechanisms of interplay between germ and gene. HLA-B27 might confer disease susceptibility by affecting immune mechanisms other than classical antigen presentation. The immunopathogenesis of joint inflammation in reactive arthritis is explored with reference to studies of humoral and cellular immune responses. Serological evidence to support the concept of molecular mimicry is far from conclusive; the results of relevant studies are summarized. Lymphocyte proliferation experiments suggest that antigen presenting cells play an important role. Finally, our views on reactive arthritis in the 1990s, and areas of new and potentially fruitful future research are presented.

Effectiveness of lymphocytapheresis in a patient with ankylosing spondylitis

Immunomodulation by lymphocytapheresis (LCA) was carried out in a patient with ankylosing spondylitis (AS) who suffered severe pain in joints and back. LCA was performed once a week and 3 x 10 9 lymphocytes were extracted each time. Fifteen courses of LCA were completed. The joint score was gradually decreased and the improvement was maintained 11 months after treatment. The population of NK cells detected by Leu-7 and Leu-11 monoclonal antibodies decreased and HLA-DR positive CD3 cells increased during and after the treatment. The effectiveness of LCA in AS may confirm the participation of immunological mechanisms in the pathogenesis of AS.

IgA nephropathy associated with ankylosing spondylitis: occurrence in women as well as in men

Two patients (one male, one female) with ankylosing spondylitis (AS) and IgA nephropathy are described. The female patient is the first reported case to have AS and IgA nephropathy concurrently. Contrary to previously reported cases, her renal manifestation preceded her rheumatic symptoms. It is suggested that women with IgA nephropathy and AS may be overlooked as the severity of spondylitis and joint involvement is less than in men.

Relation of microscopic haematuria in ankylosing spondylitis to circulating IgA containing immune complexes

Ankylosing spondylitis (AS) is associated with IgA nephropathy. To study the pathogenetic mechanism of this association the presence of haematuria and circulating IgA containing immune complexes (IgA ICs) in 70 patients with AS was determined. In this retrospective study haematuria was present in 15 patients and 25 patients had IgA ICs. Circulating IgA ICs were shown in 9/15 (60%) of the patients with haematuria and in 16/55 (29%) of those without haematuria. These results suggest that IgA ICs in patients with ankylosing spondylitis have a pathogenetic role in causing IgA nephropathy.

Characterization of circulating Yersinia-specific immune complexes in patients with yersiniosis

The size of immune complexes (ICs) containing Yersinia enterocolitica antigens was studied by size exclusion high-pressure liquid chromatography and sucrose density gradient ultracentrifugation in sera of patients with recent yersiniosis. The ICs detected were relatively small, i.e., of equal size to or slightly larger than the corresponding anti-Yersinia antibodies. The size of the ICs was equal in the patients with Yersinia-triggered reactive arthritis and in those recovering without complications. No changes were observed during a follow-up. The equal size of ICs in the patients with and without arthritis also suggests that antigens and antibodies involved are similar in both patient groups. Taken together with our earlier findings indicating occurrence of high concentrations of Yersinia IgM ICs in the arthritic patients, the present results suggest that Yersinia--IgM ICs have a role in the pathogenesis of Yersinia-triggered reactive arthritis.

Complement activation in uveitis

To determine whether complement is activated in uveitis we have measured plasma levels of C3d, a sensitive indicator of complement activation. Increased levels of C3d were found in 11 of 15 patients with idiopathic uveitis, 13 of whom had circulating immune complexes containing complement components. Since during complement activation potent mediators of inflammation are generated, it is suggested that the activation of complement, possibly triggered by uveal deposition of immune complexes, has an important role in the pathogenesis of uveitis.

Acute anterior uveitis and hepatitis B virus infection

The aetiology of acute anterior uveitis (AAU) in the great majority of cases is unclear. Various infective agents have been postulated, however, as playing a direct or indirect part in the disease process, possibly via an immune-complex vasculitis. In an earlier study we concluded that, contrary to a previous report, hepatitis B virus (HBV) played only a small role, if any, in the pathogenesis of uveitis in Great Britain. Since we did not look for other markers of HBV infection other than hepatitis B surface antigen (HBsAg), it is possible that some cases of recent HBV infection may have been missed. In the present study 49 patients with AAU were tested for markers of hepatitis B infection. Sera from all patients tested were found to be negative for HBsAg and for antibody to the HBV core (anti-HBc), excluding HBV as a significant cause of AAU in this country. Since the quest for an infective agent in AAU may remain unproductive, future research on the aetiopathogenesis of AAU should include the study of tissue 'vulnerability' and the local and systemic immunoregulatory factors which modulate inflammatory responses.

Absence of impaired lymphocyte transformation to Klebsiella spp. in ankylosing spondylitis

We have evaluated claims that impaired peripheral blood lymphocyte (PBL) transformation can occur with Klebsiella spp. in patients with ankylosing spondylitis (AS). PBL of four AS patients were cultured in vitro with autogenous faecal klebsiella, as were the PBL of age (+/- 3 years) and sex-matched pairs of 15-20 AS and normal controls cultured with heterogeneous AS-derived klebsiella and control bacterial isolates. Three of four AS patients responded to their own isolates, and no significant differences were found between the matched pairs in response to heterogeneous klebsiella isolates, including K21. Our studies did not show impaired PBL transformation with klebsiella in AS and therefore do not support claims of antigenic cross-reactivity between klebsiella and HLA-B27.

Increased incidence of recurrent hematuria in ankylosing spondylitis: a possible association with IgA nephropathy

A retrospective analysis of our patients with ankylosing spondylitis revealed a 17.8% incidence of recurrent hematuria. Two of the five patients with recurrent hematuria had previously undergone renal biopsies showing a focal proliferative glomerulonephritis. The only specimen examined by immunofluorescent staining showed the typical changes of IgA nephropathy. A control group of patients with rheumatoid arthritis did not show recurrent hematuria. Recurrent hematuria may be a frequent occurrence in ankylosing spondylitis and may signify the presence of one of the glomerulonephritides such as IgA nephropathy.

Bilateral retinal detachment in a case of Reiter's disease

A patient is described who developed co-existent Reiter's disease and bilateral non-traumatic retinal detachment. Although numerous ophthalmological disorders are associated with Reiter's disease and HLA-B27, to our knowledge this is the first report of co-existent retinal detachment. Although this relationship may be fortuitous, there are a number of immunological mechanisms common to both entities. Retinal detachment, unlike bilateral conjunctivitis and acute anterior uveitis, may be clinically asymptomatic and its sequelae prevented by appropriate ophthalmological assessment.

Serum and secretory IgA immune response to Klebsiella pneumoniae in ankylosing spondylitis

Serum and salivary IgA antibodies to Klebsiella pneumoniae were estimated by enzyme-linked immunosorbent assay (ELISA) in 53 patients with ankylosing spondylitis (AS) and 30 healthy controls. The concentrations of total serum IgA, salivary secretory component (SC) and serum C-reactive protein (CRP) were also measured. In the serum of AS patients there was a positive correlation between Klebsiella IgA antibodies and the CRP. Salivary anti-Klebsiella IgA was elevated in 39% of AS patients although this was not associated with disease activity. Serum and secretory IgA antibodies to E. coli and Pseudomonas aeruginosa were similar in patients and controls irrespective of disease activity. We conclude that part of the increase in salivary and serum IgA in AS may be due to a specific immune response to Klebsiella in the gastrointestinal tract and that serum antibodies reflect more closely those events associated with active inflammatory disease.

Factors related to the initiation and recurrence of uveitis. XL Edward Jackson memorial lecture

Uveitis comprises a complex group of diseases in which morbidity may depend on the nature of the initial inflammation as well as on the genetic, hormonal, and emotional background of the patient. Uveitis is initiated in every instance by some form of tissue injury. This may occur as an attack on individual cells by organisms such as Toxoplasma gondii or Herpesvirus hominis. Autoimmune disease may be produced as a late result of microbe-induced injury. The development of specific forms of autoimmunity seems to be dependent upon genetic as well as hormonal factors, particularly estrogens. Tissue injury of immunologic origin takes several forms, such as cytotoxic damage from sensitized lymphocytes, immune complex-mediated injury, and injury from the oxidative products of inflammatory cells. In some cases, permanent alteration of uveal vascular permeability results. Recurrent uveitis may be attributed in some instances to the reappearance of infectious organisms in the target tissue. In other cases, recurrence of inflammation may be attributed to the localization of immune complexes in the uveal tract. Changes in immunoregulation can be attributed to pregnancy, aging, and emotional factors. Neurohumoral pathways related to stress-mediated changes in immunoregulation have recently been described in laboratory animals. These pathways may be linked with stress-related recurrences of uveitis in humans.

IgA nephropathy associated with seronegative spondylarthropathies

Three patients with a seronegative spondylarthropathy were found to have IgA nephropathy. Two patients had ankylosing spondylitis (one with psoriasis), and one had incomplete Reiter's syndrome. All three had a focal proliferative glomerulonephritis with IgA-dominant mesangial immune deposits. One patient had a leukocytoclastic vasculitis. This association of IgA nephropathy with seronegative spondylarthropathies raises the possibility of a common or related pathogenesis. There is evidence to suggest that both diseases are mediated by genetically controlled immune responses to mucosal contact with etiologic antigens.

The absence of circulating immune complexes in patients with ankylosing spondylitis

Sera from 50 patients with well-defined ankylosing spondylitis were examined for circulating immune complexes using both a Clq binding (fluid phase) assay and a Raji cell assay. No more than five of the patients assessed had circulating immune complexes by either one of these techniques and none were positive in both. This result is in contrast to the high prevalence in sera from unselected patients with rheumatoid arthritis and systemic lupus used as positive controls.