Molecular evidence for the presence of chlamydia in the synovium of patients with Reiter's syndrome

British Association of Sexual Health and HIV national guideline on the management of sexually acquired reactive arthritis 2021

These guidelines update the 2008 UK guideline for the management of sexually acquired reactive arthritis. The guideline is aimed at those over the age of 16 years, presenting to healthcare professionals working in sexual health services. The recommendations are primarily aimed at services offering level 3 care in sexually transmitted infection management within the United Kingdom. However, the principles will apply to those presenting to level 1 and 2 services, and appropriate local referral pathways will need to be developed.

Chlamydia in adolescent/adult reproductive management trial study (CHARM): Clinical core protocol

INTRODUCTION

Chlamydia trachomatis (CT) is a common sexually transmitted pathogen with significant reproductive health implications. Data are mounting that the bacterial communities that reside within the vagina, collectively termed the vaginal microbiota, aid in defense against sexually transmitted infections. Disruptions in the vaginal microbiota, such as during episodes of bacterial vaginosis, may increase susceptibility to infection. Herein, we describe the clinical core protocol for a NIH NIAID Cooperative Research Center titled Eco-Pathogenomic of Chlamydial Reproductive Tract Infection. The primary goals of the project are to describe the interrelationships between the urogenital microenvironment, the properties of the pathogen and immunologic responses of the host in men and women, and their association with clinical outcomes of CT infection in women.

METHODS

Men and women with confirmed genital CT infections were recruited to a number of study protocols, including cross-sectional and longitudinal sub-studies. Participants completed a demographic and sexual health questionnaire and underwent a physical exam at baseline. In the longitudinal study arms, biologic samples were collected daily, weekly, and monthly to determine the relationships between the vaginal microbiota, prevalent CT infection, re-infection and treatment.

DISCUSSION

The biological samples and the demographic and history information collected throughout this study will be used for various analyses evaluating genomics, metabolomics and host immune responses in the context of CT infection.

Chlamydia trachomatis Genital Infections

Etiology, transmission and protection: Chlamydia trachomatis is the leading cause of bacterial sexually transmitted infection (STI) globally. However, C. trachomatis also causes trachoma in endemic areas, mostly Africa and the Middle East, and is a leading cause of preventable blindness worldwide. Epidemiology, incidence and prevalence: The World Health Organization estimates 131 million new cases of C. trachomatis genital infection occur annually. Globally, infection is most prevalent in young women and men (14-25 years), likely driven by asymptomatic infection, inadequate partner treatment and delayed development of protective immunity. Pathology/Symptomatology: C. trachomatis infects susceptible squamocolumnar or transitional epithelial cells, leading to cervicitis in women and urethritis in men. Symptoms are often mild or absent but ascending infection in some women may lead to Pelvic Inflammatory Disease (PID), resulting in reproductive sequelae such as ectopic pregnancy, infertility and chronic pelvic pain. Complications of infection in men include epididymitis and reactive arthritis. Molecular mechanisms of infection: Chlamydiae manipulate an array of host processes to support their obligate intracellular developmental cycle. This leads to activation of signaling pathways resulting in disproportionate influx of innate cells and the release of tissue damaging proteins and pro-inflammatory cytokines. Treatment and curability: Uncomplicated urogenital infection is treated with azithromycin (1 g, single dose) or doxycycline (100 mg twice daily x 7 days). However, antimicrobial treatment does not ameliorate established disease. Drug resistance is rare but treatment failures have been described. Development of an effective vaccine that protects against upper tract disease or that limits transmission remains an important goal.

Chlamydia and chronic arthritis

Certain bacterial infections have been demonstrated to be causative of reactive arthritis. The most common bacterial trigger of reactive arthritis is Chlamydia trachomatis. Chlamydia pneumoniae is another known cause, albeit far less frequently. Although Chlamydia-induced reactive arthritis will often spontaneously remit, approximately 30% of patients will develop a chronic course. Modern medicine has provided rather remarkable advances in our understanding of the chlamydiae, as these organisms relate to chronic arthritis and the delicate balance between host and pathogen. C. trachomatis and C. pneumoniae both have a remarkable ability to disseminate from the initial site of infection and establish persistently viable organisms in distant organ sites, namely the synovial tissue. How these persistent chlamydiae contribute to disease maintenance remains to be fully established, but recent data demonstrating that long-term combination antimicrobial treatment can not only ameliorate the symptoms but eradicate the persistent infection suggest that these chronically infecting chlamydiae are indeed a driving force behind the chronic inflammation. We are beginning to learn that this all appears possible even after an asymptomatic initial chlamydial infection. Both C. trachomatis and C. pneumoniae are a clear cause of chronic arthritis in the setting of reactive arthritis; the possibility remains that these same organisms are culpable in other forms of chronic arthritis as well.

Synergistic effect of ultrasound and antibiotics against Chlamydia trachomatis-infected human epithelial cells in vitro

To investigate whether or not the combined ultrasound and antibiotic treatment is effective against chlamydial infection, a new ultrasound exposure system was designed to treat chlamydia-infected cells. First, the minimum inhibitory concentrations of antibiotics against Chlamydia trachomatis were determined. Infected cultures were treated with antibiotics then sonicated at intensity of 0.15 or 0.44 W/cm(2) with or without Bubble liposomes. After 48 or 72 h after infection, chlamydial inclusions were stained and examined by fluorescence microscopy. The internalization of dextran-fluorescein conjugates by ultrasound irradiation with Bubble liposomes was observed by fluorescence microscopy. The results showed that application of nanobubble-enhanced ultrasound caused no significant effect on cell viability and chlamydial infectivity. However, Doxycycline (1/2 MIC) or CZX (1.0 μg/ml) in combination with nanobubble-enhanced ultrasound dramatically reduced the number of inclusions compared with that administered with antibiotics only. Bubble dose-dependent synergy was also observed. After ultrasound irradiation at intensity of 0.44 W/cm(2) on the presence of Bubble liposomes, 10% of HeLa cells were observed to have internalized the dextran molecules. This study suggests the possibility of using nanobubble-enhanced ultrasound to deliver antibiotic molecules into cells to eradiate intracellular bacteria, such as chlamydiae, without causing much damage to the cells itself.

Is the role of Chlamydia trachomatis underestimated in patients with suspected reactive arthritis?

Reactive arthritis is usually caused by bacteria of either the enteric or genital tracts. In the genital tract, Chlamydia trachomatis is perhaps the only aetiological agent. In Iran, newer evidence suggests that as C. trachomatis is more commonly found in the general population than was previously believed, its role in reactive arthritis may well be currently overlooked. In this review, as well as emphasizing the potential role of C. trachomatis in reactive arthritis in patients from developing countries, we also make recommendations for further clinical studies to determine its prevalence. Moreover, we also stress the need for standardization of new testing methodologies for C. trachomatis, including the use of new commercial systems in an attempt to determine a truer picture of chlamydial infection in reactive arthritis.

Broad-range PCR, cloning and sequencing of the full 16S rRNA gene for detection of bacterial DNA in synovial fluid samples of Tunisian patients with reactive and undifferentiated arthritis

Introduction

Broad-range rDNA PCR provides an alternative, cultivation-independent approach for identifying bacterial DNA in reactive and other form of arthritis. The aim of this study was to use broad-range rDNA PCR targeting the 16S rRNA gene in patients with reactive and other forms of arthritis and to screen for the presence of DNA from any given bacterial species in synovial fluid (SF) samples.

Methods

We examined the SF samples from a total of 27 patients consisting of patients with reactive arthritis (ReA) (n = 5), undifferentiated arthritis (UA) (n = 9), rheumatoid arthritis (n = 7), and osteoarthritis (n = 6) of which the latter two were used as controls. Using broad-range bacterial PCR amplifying a 1400 bp fragment from the 16S rRNA gene, we identified and sequenced at least 24 clones from each SF sample. To identify the corresponding bacteria, DNA sequences were compared to the EMBL (European Molecular Biology Laboratory) database.

Results

Bacterial DNA was identified in 20 of the 27 SF samples (74, 10%). Analysis of a large number of sequences revealed the presence of DNA from more than one single bacterial species in the SF of all patients studied. The nearly complete sequences of the 1400 bp were obtained for most of the detected species. DNA of bacterial species including Shigella species, Escherichia species, and other coli-form bacteria as well as opportunistic pathogens such as Stenotrophomonas maltophilia and Achromobacter xylosoxidans were shared in all arthritis patients. Among pathogens described to trigger ReA, DNA from Shigella sonnei was found in ReA and UA patients. We also detected DNA from rarely occurring human pathogens such as Aranicola species and Pantoea ananatis. We also found DNA from bacteria so far not described in human infections such as Bacillus niacini, Paenibacillus humicus, Diaphorobacter species and uncultured bacterium genera incertae sedis OP10.

Conclusions

Broad-range PCR followed by cloning and sequencing the entire 16S rDNA, allowed the identification of the bacterial DNA environment in the SF samples of arthritic patients. We found a wide spectrum of bacteria including those known to be involved in ReA and others not previously associated with arthritis.

Reactive and undifferentiated arthritis in North Africa: use of PCR for detection of Chlamydia trachomatis

Little is known about the possible role of Chlamydia in patients with reactive or unclassified arthritis in North Africa. This study used polymerase chain reaction (PCR) to survey this population. In addition, we compared the results in three different laboratories for PCR analyses for Chlamydia trachomatis (Ct) in synovial fluid (SF) and tissue (ST) from these North African patients with reactive arthritis (ReA), undifferentiated arthritis (UA), and in rheumatoid arthritis (RA) and osteoarthritis (OA). Eight ReA (six posturethritic, two postenteritic), 23 UA, 13 OA, and 12 RA patients were studied in Algeria, Morocco, and Tunisia. Serum, SF, and ST were obtained from each patient. Ct-PCR was performed in the three different laboratories and compared to Ct-serology [microimmunofluorescence (MIF) and anti-hsp60 enzyme-linked immunosorbent assay (ELISA)] performed in one laboratory. The rate of Ct-PCR positivity in SF/ST was low: none out of the eight ReA and three out of 23 UA patients. In the controls, Ct DNA was detected in two OA SF and in one RA SF. There was no concordance for Ct-PCR positivity between the three laboratories. MIF suggested previous Ct infection (IgG-positive) in two out of five posturethritic ReA, none out of one postenteritic ReA, one out of 17 UA, and nine out of 21 RA/OA patients tested. No MIF-positive patient was PCR-positive from SF or ST. However, anti-hsp60 IgG was detected in all four out of four patients positive by PCR and in 11 out of 44 PCR-negative patients (p = 0.002). In this multinational comparative study, the rate of Ct-PCR-positive synovial specimens in North African ReA/UA patients was low. Concordance among the three PCR testing laboratories was poor indicating the need for test standardization. All Ct-PCR-positive patients were found positive by anti-hsp60 IgG serology.

Reactive arthritis which occurred one year after acute chlamydial urethritis

A 30-year-old Japanese man developed dactylitis with sausage-like fingers in addition to balanitis and stomatitis. One year prior to these symptoms, acute chlamydial urethritis had been successfully treated by levofloxacin. On admission, Chlamydia trachomatis DNA was not detected in the urine sediment by PCR method, however, he was diagnosed to have reactive arthritis based on the clinical findings of asymmetric dactylitis, circinate balanitis, stomatitis and positivity for HLA B27 antigen. He was treated with methotrexate and his arthritis improved. The past chlamydial infection may have been involved in the pathogenesis of reactive arthritis in this patient.

Immune-mediated control of Chlamydia infection

Infection with the bacterium Chlamydia trachomatis can lead to a variety of diseases, including ectopic pregnancy, infertility and blindness. Exposure of the host to C. trachomatis stimulates multiple innate and adaptive immune effectors that can contribute towards controlling bacterial replication. However, these effectors are often insufficient to resolve the infection and prevent re-infection, and the continued presence of C. trachomatis within the host may induce immune effectors to chronically produce inflammatory cytokines. This may eventually lead to the tissue pathologies associated with the infection. Reducing the incidence and sequelae of infection will ultimately require the development of a C. trachomatis vaccine that can stimulate sterilizing immunity while avoiding immune-mediated pathology.

Effects of levofloxacin and doxycycline on interleukin-6 production of Chlamydia trachomatis-infected human synovial fibroblasts

BACKGROUND

A large amount (80,000-100,000 pg/ml) of interleukin-6 (IL-6) was detected in cultures of human synoviocytes infected with Chlamydia trachomatis. In this study, we investigated the effect of antibiotics on the IL-6 production of C. trachomatis-infected human fibroblast-like synovial cells (HFLS).

METHODS

The minimum inhibitory concentrations of levofloxacin and doxycycline against C. trachomatis were determined in either HFLS or HeLa 229 cells. The number of live Chlamydia was also examined. IL-6 in the supernatants of infected cultures was quantified by capture ELISA.

RESULTS

The production of IL-6 was suppressed to as low as 1,800 pg/ml in the infected HFLS treated with levofloxacin or doxycycline immediately or early after infection. In HFLS treated with levofloxacin and doxycycline, the IL-6 levels decreased to 37,000 and 21,000 pg/ml, respectively, 48 h after infection, and levofloxacin was thus found to be less effective than doxycycline. In addition, the number of viable C. trachomatis in the infected cultures treated with levofloxacin 24 h after infection was higher than when treated with doxycycline.

CONCLUSIONS

The early administration and proper selection of antibiotics is important for the suppression of inflammatory cytokine production. These findings indicate that antibiotic therapy will not only work in treating infections but might also be useful in treating reactive arthritis secondary to the infection.

Early cytokine profiles in the joint define pathogen clearance and severity of arthritis inChlamydia-induced arthritis in rats

OBJECTIVE

Although Chlamydia trachomatis-induced arthritis is among the most common rheumatic diseases having an identified infectious trigger, the pathogenesis of this arthritis is not well defined. We sought to investigate the host-microbe interactions that contribute to the severity of arthritis initiated by chlamydial infection.

METHODS

We established an experimental rat model of C. trachomatis-induced arthritis that recapitulates many pathologic features of the clinical disease. The severity of the arthritis was defined using an established histopathologic scoring system. Host clearance of the pathogen and local cytokine production were examined by enzyme-linked immunosorbent assays.

RESULTS

Lewis rats were susceptible to C. trachomatis-induced arthritis, whereas BN rats were relatively resistant to this disease. Significant differences in the histopathologic severity of arthritis were originally observed on day 21, and this prompted an examination of the acute phase of the arthritis. As early as day 5 after the onset of the arthritis, pathologic changes in Lewis rats were more severe than those in BN rats. An evaluation of the role of complement using cobra venom factor treatment excluded complement as being the key to differential sensitivity, because decomplementation did not eliminate the differences in arthritis severity between Lewis and BN rats. Host clearance, in contrast, was significantly different between the rat strains, with BN rats showing more prompt and effective clearance of the pathogen from both synovial tissues and spleen compared with Lewis rats. Local cytokine profiles demonstrated that host resistance was characterized by enhanced synovial expression of tumor necrosis factor alpha, interferon-gamma (IFNgamma), and interleukin-4.

CONCLUSION

These studies demonstrated that cytokines thought to be proinflammatory in nature can play an important role in host defense in infection-triggered arthritis and serve to highlight the dynamic cytokine relationships that constitute effective host-pathogen interactions.

In vitro assessment of the APTIMA Combo 2 assay for the detection of Chlamydia trachomatis using highly purified elementary bodies

The Gen-Probe APTIMA Combo 2 assay has previously been reported to have a high sensitivity. The end point of this assay was evaluated using highly purified chlamydial elementary bodies (EBs). The performance of the APTIMA Combo 2 assay was compared with a commercially available PCR kit, AMPLICOR Chlamydia trachomatis. The number of inclusions of C. trachomatis at the end point of the APTIMA Combo 2 assay was 0.005 inclusion-forming units (i.f.u.) ml(-1), which was equivalent to 0.008 EBs per assay. The end point of the AMPLICOR kit was 5 i.f.u. ml(-1) (equivalent to 0.5 EB per assay). The efficacy of the AMPLICOR C. trachomatis assay was inhibited by phosphate or Fe2+ ion, while these had no effect on the APTIMA Combo 2 assay. In conclusion, the APTIMA Combo 2 assay appears to have a greater sensitivity than the AMPLICOR C. trachomatis assay for detection of C. trachomatis, while demonstrating few problems with inhibitory substances such as phosphate and Fe2+ ion.

The occurrence of antibodies against chlamydia species in patients with monoarthritis and chronic closed lock of the temporomandibular joint

PURPOSE

The study goal was to investigate the occurrence of serum antibodies to Chlamydia trachomatis, Chlamydia pneumoniae, and Chlamydia psittaci in patients with temporomandibular joint (TMJ) monoarthritis or chronic closed lock and in control subjects.

PATIENTS AND METHODS

An indirect microimmunofluorescence test for detecting antibodies against C trachomatis was used. Twenty-three patients (12 with monoarthritis and 11 with chronic closed lock) and 42 control subjects were evaluated.

RESULTS

Six patients with monoarthritis, 5 patients with chronic closed lock of the TMJ, and 6 control individuals were considered to have had a past C trachomatis infection based on their immunoglobulin G titers. Corresponding groups for C pneumoniae investigation included 3 patients with monoarthritis, 4 patients with chronic closed lock, and 17 control subjects, and for C psittaci, 1 patient with monoarthritis, 2 patients with chronic closed lock, and 1 control subject. Statistically significant differences between patients and control subjects were found for C trachomatis only; monoarthritis versus control (P =.016), chronic closed lock versus control (P =.038), and all patients versus control (P =.007). Patients with monoarthritis did not differ from patients with chronic closed lock with regard to antibodies against C trachomatis.

CONCLUSION

The occurrence of serum antibodies to C trachomatis was significantly higher in patients than in control subjects, but this occurrence did not correlate with severity of observed tissue changes. Nevertheless, an association may exist between the presence of C trachomatis and TMJ disease.

Wide range of Chlamydiales types detected in native Australian mammals

The Chlamydiales are a unique order of intracellular bacterial pathogens that cause significant disease of birds and animals, including humans. The recent development of a Chlamydiales-specific 16S rDNA polymerase chain reaction (PCR) assay has enabled the identification of Chlamydiales DNA from an increasing range of hosts and environmental sources. Whereas the Australian marsupial, the koala, has previously been shown to harbour several Chlamydiales types, no other Australian marsupials have been analysed. We therefore used a 16S rDNA PCR assay combined with direct sequencing to determine the presence and genotype of Chlamydiales in five wild Australian mammals (gliders, possums, bilbies, bandicoots, potoroos). We detected eight previously observed Chlamydiales genotypes as well as 10 new Chlamydiales sequences from these five Australian mammals. In addition to PCR analysis we used antigen specific staining and in vitro culture in HEp-2 cell monolayers to confirm some of the identifications. A strong association between ocular PCR positivity and the presence of clinical disease (conjunctivitis, proliferation of the eyelid) was observed in two of the species studied, gliders and bandicoots, whereas little clinical disease was observed in the other animals studied. These findings provide further evidence that novel Chlamydiales infections occur in a wide range of hosts and that, in some of these, the chlamydial infections may contribute to clinical disease.

[Diagnostic significance of synovial biopsy in patients with Reiter's syndrome]

INTRODUCTION

Arthritis in Reiter's syndrome (RS) is a reactive synovitis associated with a localized infection of the urogenital or gastrointestinal tract with a genetic predisposition. The pathogenetic mechanisms for synovitis in RS are still unknown. Our aim was to examine some of the pathogenetic mechanisms in Reiter's syndrome looking for morphologic changes, immunoprotein deposits and microorganism antigens in synovial biopsies and to determine whether synovial biopsy is useful in diagnosis of RS.

MATERIAL AND METHODS

Thirty patients with urogenital form of RS were examined within a four-year period. Table 1 illustrates laboratory findings in our patients. We performed synovial biopsies looking for histopathological changes, deposits of immunoproteins and microorganism antigens. Analysis of synovial biopsy specimens was performed using light and immunofluorescence microscopy and fluorescein-labelled monoclonal antibodies to Chlamydia trachomatis.

RESULTS

Histopathological examination of synovial membrane revealed marked proliferation of the synovial lining cells (SLC) with less or more abundant papillary projections, hypertrophic and edematous tissue with marked vascularisation in 28 (93.3%) cases. Fibrinoid necrosis foci were seen on the surface of synovial tissue. Chronic inflammatory cells (CIC) were diffusely distributed. Edema of the vessel walls, swollen endothelial cells, fibrinoid necrosis in vessel walls as well as multilaminated basement membranes were observed. All histopathologic changes are presented in Table 2. Immunofluorescent techniques in 12 out of 30 (40%) synovial membranes showed immunoglobulin deposits: IgG and IgA deposits were found in vessel walls in 7 cases each and IgM in 10 biopsy specimens. C3 was present perivascularly or within the vessel wall in 4 (13.3%) cases. Sections treated using fluorescein-conjugated antibody revealed Chlamydia in the synovial tissue in 2 patients.

CONCLUSION

Biopsy specimens with previously described changes in patients with suspected Reiter's syndrome can be useful to confirm the diagnosis. According to our experience, multiple biopsies of abnormal synovia are recommended in these patients.

Infection of human fibroblast-like synovial cells with Chlamydia trachomatis results in persistent infection and interleukin-6 production

Recent studies have shown that the urogenital pathogen Chlamydia trachomatis to be a major bacterium triggering reactive arthritis (ReA), and is able to induce interleukin-6 (IL-6) production in human fibroblast-like synovial cells (FSC) in vitro. In the present study, we examined the correlation between IL-6 production and multiplication of chlamydia in FSC. All FSC from five patients secreted highly increased quantities of IL-6 in a dose-dependent and time-dependent fashion. Heat and UV inactivated chlamydia failed to enhance production of IL-6. When azithromycin was added to infected cultures of FSC at 0 or 48 h after infection, the level of IL-6 production was very low. Transmission electron microscopy of such infected cultures revealed many abnormal forms of chlamydia within the inclusions in FSC. From one step-growth curve experiments, it was suggested that C. trachomatis hardly multiplied in FSC. In contrast, in C. trachomatis infected HeLa 229 cells, chlamydia multiplied as usual, but little IL-6 production were found. These observations indicated that live chlamydia and the persistence of chlamydia may be essential for stimulating the synthesis of IL-6 in FSC.

Differential expression of genes encoding membrane proteins between acute and continuous Chlamydia pneumoniae infections

Chlamydia pneumoniae is associated with several chronic human diseases, including chronic obstructive pulmonary disease and atherosclerotic cardiovascular disease. During chronic disease, organisms are believed to exist in a persistent phase that is not well understood at the genetic level. Long-term in vitro continuous infections are spontaneously persistent and are less susceptible than in vitro acute infections to treatment with antibiotics, and are therefore particularly relevant as an in vitro model of in vivo chronic disease. Real-time reverse transcriptase-PCR (r-t RT-PCR) was used to quantitate transcript copy numbers of 13 genes in continuous and acute infections with C. pneumoniae. The set of genes studied encodes proteins with known or predicted functions in the cell membrane, the inclusion membrane, cell division, metabolism, and immunopathology. Significant upregulation was seen for five genes (CPn0483, nlpD, ompA, pmp1 and porB) in continuous cultures. The genes omcB, pmp1, and porB, all of which encode membrane proteins, shared similar patterns of expression over both acute and continuous profiles. These results show that Chlamydia in the long-term continuous model of persistence have a unique transcription profile, adding to our knowledge of regulation of this important stage of chlamydial growth.

Isolation of Chlamydia trachomatis or Ureaplasma urealyticum from the synovial fluid of patients with Reiter's syndrome

BACKGROUND

The aim of this study was to contribute to the insight of the role of the infectious agent in ethiopathogenesis of the Reiter's syndrome development, which could directly influence the choice of treatment of these patients.

METHODS

Eighteen patients with urogenital form of the Reiter's syndrome and 16 controls (6 with rheumatoid arthritis and 10 with pigmented villonodular synovitis) were included in the study. In all patients standard laboratory analyses of the blood, urine and stool were made; antibody titer to Chlamydia trachomatis and Ureaplasma urealyticum was determined in synovial fluid and serum; isolation of Chlamydia trachomatis and Ureaplasma urealyticum in urethral, cervical and conjunctival swabs, as well as in prostatic and synovial fluid, was also made. HLA typing was done, too. Chlamydia was isolated in the McCoy cell culture treated with cycloheximide, while Ureaplasma was identified according to its biochemical properties grown on cell-free liquid medium.

RESULTS

Chlamydia trachomatis was isolated from the synovial fluid of 4 patients with Reiter's syndrome (22.2%), while Ureaplasma urealyticum was isolated in 7 of them (38.9%). These microorganisms were not found in any synovial fluid of the control group patients.

CONCLUSION

Presence of these bacteria in the inflamed joint might be an important factor in etiopathogenesis of this disease, and it supports the hypothesis that arthritis in Reiter's syndrome is probably of the infectious origin.

Reactive arthritis or chronic infectious arthritis?

Microbes reach the synovial cavity either directly during bacteraemia or by transport within lymphoid cells or monocytes. This may stimulate the immune system excessively, triggering arthritis. Some forms of ReA correspond to slow infectious arthritis due to the persistence of microbes and some to an infection triggered arthritis linked to an extra-articular site of infection.

The basis of the synovial fluid analysis

Synovial fluid fills the spaces in the joint cavities. Many diseases can affect the joints and frequently only a direct examination of the tissue or synovial fluid will yield the correct diagnosis. The article presents the basis of the synovial fluid analysis and a relevant decision-making scheme. The reliability and applicability of synovial fluid tests are commented upon. The synovial fluid analysis undoubtedly plays an important role in the management of patients with joint diseases. Due to a lack of interlaboratory comparisons, and therefore expert opinions on the interpretation of results, this knowledge and the acquisition of relevant experience should be encouraged to enable evaluation of the clinical applicability of recent discoveries in synovial fluid pathology.

Substance P and mast cells: preliminary histologic analysis of the human temporomandibular joint

PURPOSE

Neuropeptide-containing nerves can serve as a mechanism for nervous system regulation of host defense responses. Because bacteria associated with reactive arthritis have been identified in the temporomandibular joint (TMJ), this study investigates whether the presence of substance P (SP) neuropeptide-containing nerves and mast cells can be identified in the TMJ.

MATERIAL AND METHODS

Posterior bilaminar tissue removed during TMJ surgery from 9 women was evaluated for the presence of neuropeptide-containing nerves by staining with a monoclonal antibody to SP. Staining of the TMJ tissue sections with 0.5% toluidine blue was performed to identify the presence of mast cells.

RESULTS

SP-containing nerves and mast cells were identified within the posterior bilaminar tissue associated with the vasculature.

CONCLUSIONS

The presence of neuropeptide nerves and mast cells within the TMJ has been shown. Mast cell degranulation products and SP release can contribute to TMJ inflammation.

Immune response to chlamydial 60-kilodalton heat shock protein in tears from Nepali trachoma patients

Although the host immune response to the 60-kDa chlamydial heat shock protein (hsp60) has been implicated in trachoma pathogenesis, no studies have examined mucosal immune responses to hsp60 in populations for which chlamydia is endemic. Tears and sera from Nepali villagers were reacted against hsp60 fusion proteins, whole hsp60, and the major outer membrane protein (MOMP). Tears from villagers without disease were anti-hsp60 immunoglobulin G (IgG) reactive in 6 (38%) of 16 villagers compared with 36 (90%) of 40 with follicular trachoma (TF) (P < 0.001); 47 (89%) of 53 with inflammatory trachoma (TI) (P < 0.001); and 31 (84%) of 37 with conjunctival scarring (TS) (P = 0.002). By multivariate analysis, odds ratios for tear hsp60 IgG immunoreactivity in villagers with TF, TI, and TS were 49.2 (confidence interval [CI], 2.7 to 898), 22.6 (CI, 3 to 170), and 13.6 (CI, 1.4 to 133), respectively. There were no significant differences for tear IgA or secretory IgA (sIgA) reactivity to hsp60 or for tear sIgA and IgG reactivity to MOMP. Serum anti-hsp60 IgG immunoreactivity was associated with TI only. These data suggest that anti-hsp60 IgG immunoreactivity represents largely locally derived antibodies, which may promote disease pathology. In contrast, nonspecific high rates of anti-hsp60 sIgA antibodies suggest chronic or repeat stimulation from an endemic source of organisms.

The anti-idiotypic antibody to chlamydial glycolipid exoantigen (GLXA) protects mice against genital infection with a human biovar of Chlamydia trachomatis

Despite more than three decades of anti-chlamydial vaccine research and improved vaccine strategies with new technologies, no vaccine candidate has protected against heterologous challenge, nor at more than one site of infection. The majority of experimental anti-chlamydial vaccines to date have targeted the chlamydial major outer membrane protein (MOMP). Many MOMP-directed vaccine candidates have been highly immunogenic, but have failed to protect against infectious challenge. We have extended our previous studies of a different anti-chlamydial vaccine, a monoclonal anti-idiotypic antibody (anti-Id; mAb2) which is a molecular mimic of the chlamydial glycolipid exoantigen (GLXA). The present studies demonstrate that the mAb2 vaccine is protective in a murine genital infection model utilizing a human urogenital strain. After either mucosal (oral or intranasal) or systemic (subcutaneous) immunization with the poly (lactide) encapsulated-mAb2 to GLXA, C3H/HeJ mice were significantly protected against topical vaginal challenge with Chlamydia trachomatis (K serovar; UW-31). Reduced vaginal shedding of organism and genital tract inflammation were associated with GLXA-specific and/or anti-EB neutralizing serum antibody. Our results demonstrate that the anti-Id (mAb2) vaccine is protective against an additional human biovar of C. trachomatis in C3H/HeJ mice, which are allogeneic to the source of mAb2 (BALB/c).

Indirect evidence of intra-articular immunoglobulin G synthesis in patients with Chlamydia trachomatis reactive arthritis

OBJECTIVES

To investigate whether B-cell stimulation occurs in joints of Chlamydia trachomatis reactive arthritis patients by comparing the immunoglobulin G (IgG) anti-C. trachomatis antibody responses in serum and synovial fluid (SF).

METHODS

The number and spectrum of C. trachomatis antigens recognized by paired serum and SF samples from 16 patients with C. trachomatis reactive arthritis and 20 patients with other inflammatory arthropathies independent of this bacteria, were studied by immunoblotting. The responses to five different Chlamydia antigens were also determined in enzyme-linked immunosorbent assays.

RESULTS

In C. trachomatis reactive arthritis patients, a higher number of C. trachomatis antigens was recognized by SF (17.6+/-5.1) than by serum (11.1+/-6.3) IgG and a higher intensity of SF IgG binding to the outer membrane protein 2 (OMP2) was observed.

CONCLUSIONS

These results suggest an intra-articular IgG production and a possible role of some Chlamydia antigens like OMP2 in the pathogenesis of C. trachomatis reactive arthritis.

Sexually-acquired reactive arthritis

Reactive arthritis is the most frequent cause of acute peripheral arthritis in young men. The aetiopathogenesis of reactive arthritis is reviewed, together with the varied clinical features. Finally the treatment and prognosis of this challenging condition are discussed.

Chlamydia trachomatis nucleic acids can be found in the synovium of some asymptomatic subjects

OBJECTIVE

The recent identification of antigens or nucleic acids of infectious agents in the joints of patients with reactive arthritis has raised questions about whether chlamydial or other infectious agent nucleic acids are also present in normal joints. We had the opportunity to study synovium from 30 asymptomatic volunteer subjects by use of polymerase chain reaction (PCR) for attempted identification of Chlamydia and other infectious agents.

METHODS

All subjects had blind needle synovial biopsies with the Parker-Pearson needle. DNA was extracted and PCR performed using primers for Chlamydia trachomatis, Chlamydia pneumoniae, Borrelia burgdorferi, and pan bacterial 16S ribosomal RNA (rRNA).

RESULTS

Two subjects were identified with nucleic acid for the 16S rRNA gene of C trachomatis. All other PCR reactions were negative except for the pan bacterial 16S rRNA in the C trachomatis-positive subjects. Both subjects, although symptom free, had some evidence of synovial reaction.

CONCLUSION

C trachomatis appears to occasionally be disseminated to joints without producing overt disease.

Identification of Chlamydia trachomatis in the human temporomandibular joint

PURPOSE

Reactive arthritis (ReA) as a consequence of triggering Chlamydia trachomatis infections has been extensively studied to better understand inflammatory arthritis. This study investigated whether the presence of C trachomatis can be shown in the TMJ of patients with internal derangement.

PATIENTS AND METHODS

Posterior bilaminar tissue removed from 31 patients (29 F, 2 M) during TMJ articular disc repositioning and posterior ligament repair was tested for the presence of C trachomatis. Cryosections were stained using a monoclonal antibody that identifies all chlamydial serovars. Highly specific polymerase chain reaction (PCR) assays independently targeting two genes of C trachomatis also were performed; these assays also identify all serovars of this organism.

RESULTS

TMJ tissue from 6 of 30 patients (20%) showed the presence of C trachomatis in the posterior bilaminar tissue on immunostaining. PCR screening identified 12 of 31 patients (39%) as having C trachomatis DNA in tissue, including four of six positive by immunostaining. All chlamydia-positive patients were female, with an average age of 36.7 years (15 to 48 years).

CONCLUSIONS

The presence of C trachomatis in the human TMJ has not been previously shown. The presence of this organism may serve as the pathogenetic mechanism for TMJ dysfunction, as demonstrated in other joints. Nonapparent chlamydial infection in females may also explain the marked prevalence of TMJ symptoms in women.

Whipple's arthritis: direct detection of Tropheryma whippelii in synovial fluid and tissue

We describe 2 patients presenting with polyarthritis in whom the synovial fluid (1 patient) or synovial tissue (1 patient) was positive for Tropheryma whippelii, the Whipple's disease-associated bacillus, when examined by polymerase chain reaction (PCR) and DNA sequencing. Histopathologic findings were consistent with articular Whipple's disease in the synovial fluid of 1 patient and the synovial tissue of the other. In both patients, bowel mucosal specimens were negative for Whipple's disease features by histologic and PCR methods. One patient was positive for T whippelii in the peripheral blood. Control synovial fluid specimens from 40 patients with other arthritides, including Lyme arthritis, were negative. Sequencing of a 284-basepair region of the 16S ribosomal RNA gene confirmed that the sequence is closely related to the known T whippelii sequence. Both patients responded to treatment with antibiotics.

Therapeutic aspects of spondyloarthropathies -- a review

In the pathogenesis of spondyloarthropathies, infection and gut inflammation are the most important external triggering factors. Early antimicrobial therapy to treat urethritis caused by Chlamydia trachomatis is effective in preventing a recurrent reactive arthritis. When the arthritis appear, a short term conventional antimicrobial therapy is unable to modify its course. In acute chlamydia arthritis, patients benefit from a prolonged (3-month) treatment with tetracycline, while such a treatment has not proved to be effective in enteroarthritis or in chronic forms of reactive arthritis. The role of sulfasalazine in the treatment of patients with spondyloarthropathies is controversial. It might modify the disease course during acute and chronic reactive arthritis, and is working for patients with ankylosing spondylitis, especially patients with peripheral arthritis. Data showing an effect of sulfasalazine in the prevention of chronic spondyloarthropathy or in modification of the long-term prognosis of ankylosing spondylitis are, however, lacking.

In situ hybridisation and direct fluorescence antibodies for the detection of Chlamydia trachomatis in synovial tissue from patients with reactive arthritis

BACKGROUND

Chlamydia trachomatis is associated with Reiter's syndrome and reactive arthritis but the form in which the organism survives in synovial cells is unclear.

AIM

To compare in situ hybridisation with direct fluorescence in the detection of inapparent chlamydial infection in synovial tissue.

METHODS

Synovial tissue from four patients with reactive arthritis patients was examined using biotin labelled probes for chlamydial DNA and fluorescein isothiocyanate (FITC) labelled monoclonal antibodies against the major outer membrane protein.

RESULTS

In two of the four patients, evidence of chlamydial infections was detected by in situ hybridisation in parallel sections but not with FITC labelled monoclonal antibodies.

CONCLUSIONS

Detection of chlamydial DNA by in situ DNA hybridisation may be a better way to identify chlamydial infection in synovial tissue than phenotype targeting with FITC conjugated antibodies, which is used as a standard procedure for screening clinical specimens for chlamydia.

Pathogenesis of human leukocyte antigen B27-positive arthritis. Information from clinical materials

In the spondyloarthropathies human leukocyte antigen (HLA) B27 confers a strong genetic predisposition to the development and to the chronicity of disease after extra-articular infection with certain gram-negative bacteria. The close relationships between infection, HLA-B27, other genetic factors, and the host immune system, however, still are unexplained. HLA-B27-positive arthritis continues to be an area of intensive investigation in basic and clinical research. New animal models with HLA-B27 transgenic mice and rats, as well as recent developments in understanding the processes involved in signal transduction, cytokine production, and human T-lymphocyte activation, contribute to the development of new pathogenic models of the spondyloarthropathies. This article summarizes the current concepts of the cause and pathogenesis of the spondyloarthropathies resulting from studies of clinical materials. The host-microbial interplay in human disease, namely in bacteria-induced reactive arthritis, may eludicate principle disease mechanisms in acute disease and in the development of chronic autoimmune arthritis or ankylosing spondylitis.

Bacterial antigens in reactive arthritis and spondarthritis. Rational use of laboratory testing in diagnosis and follow-up

An aetiological diagnosis of reactive arthritis is based on the demonstration of recent or ongoing infection with the causative bacterium. This may be done by serological demonstration of antibacterial antibodies, demonstration of the causative microorganism at an extra-articular site or by identification of bacterial nucleic acids or antigens in joint material from patients with aseptic arthritis. The finding of elevated titres of bacteria-specific IgG- and IgA-class antibodies may indicate recent or persistent infection, but has some limitations due to the prevalence of such antibodies among apparently healthy individuals and the persistence of such antibodies after the infection. While Chlamydia can be demonstrated in urogenital specimens in at least one-third of patients with Chlamydia-induced arthritis, the triggering microorganisms are usually no longer detectable in post-dysenteric reactive arthritides. Assays involving molecular amplifications have been successfully used to demonstrate bacterial nucleic acids in joint specimens from patients with reactive arthritis. In addition, bacterial antigens have been detected by immunofluorescence tests. Even though examination of synovial fluid and synovial membrane specimens for bacterial DNA by the polymerase chain reaction is increasingly used to diagnose reactive arthritis, such assays have not been standardized and are not generally available. While some problems remain, these techniques will facilitate the exact diagnosis of reactive arthritides in the near future.

Reiter's syndrome. Diagnosis and clinical features

After a short review of the history of Reiter's diseases, new definitions of what is now called reactive arthritis are proposed. The best definition is based on a multiple-entry set of criteria validated by other members of the spondyloarthropathy group. This definition needs no reference to origin hypothesis and no exclusion criteria. The epidemiology of Reiter's syndrome is also discussed, and the problems due to previously imprecise definitions are emphasized. Clinical features are described and divided into four syndromes: peripheral arthritis, enthesopathic, pelvic and axial, and extramusculoskeletal syndromes; seven predictive factors of long-term evolution are proposed. Differential diagnosis is discussed within and without the spondyloarthropathy group.

The spondylarthropathies: classification and diagnosis. Do we need new terminologies?

The present classification of a number of arthropathies linked to the B27 antigen under the term spondylarthropathy emphasises the frequent familial aggregation and clustering during follow-up of these diseases. This article is an attempt to review the progress elicited by the introduction of classification criteria for spondylarthropathy and the limitations of the concept. In particular, we address the continued need for better understanding of aetiology and pathogenesis. This makes it likely that we will need new classifications in the future and that this will evolve along with improvements in disease understanding. Working classifications that include the infectious triggers and features of the host response might be useful to guide new approaches.

The pathogenesis of HLA-B27 arthritis: role of HLA-B27 in bacterial defense

The way in which a host accommodates invasive facultative intracellular bacteria must be the key to the development of reactive arthritis. Investigators have analyzed the bacterial events at several levels: invasion into host cells, intracellular survival, translocation from the sites of infection to the joints, residence in the joints, and evasion of host defense. Because HLA-B27 is present in higher incidence in patients with reactive arthritis and is an essential gene in the related ankylosing spondylitis, the role of HLA-B27 in host defense is also assumed to be important in the development of reactive arthritis. This review summarizes the various studies in this field.