Reactive arthritis in patients attending an urban sexually transmitted diseases clinic

Systematic Literature Review and Quantitative Analysis of Health Problems Associated with Sexually Transmitted Neisseria gonorrhoeae Infection

Objective

Neisseria gonorrhoeae (Ng) is the second most common sexually transmitted bacterial infection (STI), leading to serious health problems in men, women and newborns. While early antibiotic treatment is effective, infections are increasingly antibiotic-resistant. No systematic reviews present health problems associated with Ng infections or their likelihood of occurrence. The objective, therefore, was to conduct a systematic literature review to address these gaps.

Methods

A systematic literature review was conducted of all studies with an English abstract published since 1950 (Pubmed)/1966 (Embase). The search included patients with a history of/current sexually transmitted Ng infection. Expected outcomes were defined from published reviews of gonorrhoea health problems. Observational studies with a control group were included. A decision tree determined the best quality studies for each outcome, prioritising generalisable populations, laboratory-confirmed diagnosis, clearly defined outcomes, no STI co-infections, adjusted analyses and risk estimates. Where feasible, a meta-analysis was performed; otherwise, the best quality study estimates were identified.

Findings

In total, 46 studies were included, and 22 health problems were identified. Of these problems, Ng infection was statistically significantly associated with preterm premature ruptures of membranes, preterm birth, low birth weight, stillbirth, infant death, neonatal ophthalmia, schizophrenia in offspring, pelvic inflammatory disease and subsequent tubal infertility, human immunodeficiency virus and prostate cancer/problems. High-quality evidence was generally lacking, with high heterogeneity across studies, and limited or inconclusive data on other health problems.

Conclusion

Ng infection is associated with severe health problems in women, men and newborns. More high-quality comparative studies are needed to address the limitations in current knowledge.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40121-021-00481-z.

Reactive arthritis in the right hip following COVID-19 infection: a case report

BACKGROUND

SARS-COV-2 usually presents with respiratory symptoms but can have various other manifestations and sequelae. One of the rare complications of COVID-19 infection is Reactive Arthritis. While this complication is more likely to occur following sexually transmitted or gastrointestinal infections, other infections such as COVID-19 can lead to reactive arthritis as well.

CASE PRESENTATION

Herein, we report a 58 year old woman hospitalized following COVID-19 infection and was discharged after a week. She consequently presented to the clinic ten days after her discharge, complaining of walking difficulties and radiating pain in her right hip. After ultrasound and MRI, she was diagnosed with reactive arthritis inflammation in the hip's neck. Other known microorganisms responsible for reactive arthritis were ruled out before attributing it to the earlier COVID-19 infection. Clinical symptoms were resolved after being treated using a combination of indomethacin and depot methyl-prednisolone for 14 days.

CONCLUSION

Latest evidence shows that COVID-19 can lead to autoimmune reactions, including reactive arthritis. Further attention should be paid to symptoms occurring after an episode of infection with COVID-19 to expand our understanding of the disease and the symptoms with which it can manifest.

Mediation of Interleukin-23 and Tumor Necrosis Factor-Driven Reactive Arthritis by Chlamydia-Infected Macrophages in SKG Mice

OBJECTIVE

ZAP-70^W163C BALB/c (SKG) mice develop reactive arthritis (ReA) following infection with Chlamydia muridarum. Since intracellular pathogens enhance their replicative fitness in stressed host cells, we examined how myeloid cells infected with C muridarum drive arthritis.

METHODS

SKG, Il17a-deficient SKG, and BALB/c female mice were infected with C muridarum or C muridarum luciferase in the genitals. C muridarum dissemination was assessed by in vivo imaging or genomic DNA amplification. Macrophages were depleted using clodronate liposomes. Anti-tumor necrosis factor (anti-TNF) and anti-interleukin-23p19 (anti-IL-23p19) were administered after infection or arthritis onset. Gene expression of Hspa5, Tgtp1, Il23a, Il17a, Il12b, and Tnf was compared in SKG mice and BALB/c mice.

RESULTS

One week following infection with C muridarum, macrophages and neutrophils were observed to have infiltrated the uteri of mice and were also shown to have carried C muridarum DNA to the spleen. C muridarum load was higher in SKG mice than in BALB/c mice. Macrophage depletion was shown to reduce C muridarum load and prevent development of arthritis. Compared with BALB/c mice, expression of Il23a and Il17a was increased in the uterine and splenic neutrophils of SKG mice. The presence of anti-IL-23p19 during infection or Il17a deficiency suppressed arthritis. Tnf was overexpressed in the joints of SKG mice within 1 week postinfection, and persisted beyond the first week. TNF inhibition during infection or at arthritis onset suppressed the development of arthritis. Levels of endoplasmic reticulum stress were constitutively increased in the joints of SKG mice but were induced, in conjunction with immunity-related GTPase, by C muridarum infection in the uterus.

CONCLUSION

C muridarum load is higher in SKG mice than in BALB/c mice. Whereas proinflammatory IL-23 produced by neutrophils contributes to the initiation of C muridarum-mediated ReA, macrophage depletion reduces C muridarum dissemination to other tissues, tissue burden, and the development of arthritis. TNF inhibition was also shown to suppress arthritis development. Our data suggest that enhanced bacterial dissemination in macrophages of SKG mice drives the TNF production needed for persistent arthritis.

Reactive arthritis after COVID-19 infection

Reactive arthritis (ReA) is typically preceded by sexually transmitted disease or gastrointestinal infection. An association has also been reported with bacterial and viral respiratory infections. Herein, we report the first case of ReA after the he severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. This male patient is in his 50s who was admitted with COVID-19 pneumonia. On the second day of admission, SARS-CoV-2 PCR was positive from nasopharyngeal swab specimen. Despite starting standard dose of favipiravir, his respiratory condition deteriorated during hospitalisation. On the fourth hospital day, he developed acute respiratory distress syndrome and was intubated. On day 11, he was successfully extubated, subsequently completing a 14-day course of favipiravir. On day 21, 1 day after starting physical therapy, he developed acute bilateral arthritis in his ankles, with mild enthesitis in his right Achilles tendon, without rash, conjunctivitis, or preceding diarrhoea or urethritis. Arthrocentesis of his left ankle revealed mild inflammatory fluid without monosodium urate or calcium pyrophosphate crystals. Culture of synovial fluid was negative. Plain X-rays of his ankles and feet showed no erosive changes or enthesophytes. Tests for syphilis, HIV, anti-streptolysin O (ASO), Mycoplasma, Chlamydia pneumoniae, antinuclear antibody, rheumatoid factor, anticyclic citrullinated peptide antibody and Human Leukocyte Antigen-B27 (HLA-B27) were negative. Gonococcal and Chlamydia trachomatis urine PCR were also negative. He was diagnosed with ReA. Nonsteroidal Anti-Inflammatory Drug (NSAID)s and intra-articular corticosteroid injection resulted in moderate improvement.

Chlamydia-Induced Reactive Arthritis: Disappearing Entity or Lack of Research?

PURPOSE OF REVIEW

Recent studies regarding the frequency of Chlamydia-induced reactive arthritis (ReA) are reviewed, with a focus on the question of whether the entity is in fact disappearing or whether it is simply being underdiagnosed/underreported. Epidemiological reports indicate diversity in the frequency of Chlamydia-associated ReA in various parts of the world, with evidence of declining incidence in some regions.

RECENT FINDINGS

The hypothesis that early effective treatment with antibiotics prevents the manifestation of Chlamydia-associated ReA requires further investigation. For clinicians, it is important to remember that ReA secondary to Lymphogranuloma venereum (LGV) serovars L1-L3 of C. trachomatis is probably underestimated due to a limited awareness of this condition, the re-emergence in Western countries of LGV overall, and the present increasingly rare classical inguinal presentation.

Spondyloarthritis, Acute Anterior Uveitis, and Fungi: Updating the Catterall-King Hypothesis

Spondyloarthritis is a common type of arthritis which affects mostly adults. It consists of idiopathic chronic inflammation of the spine, joints, eyes, skin, gut, and prostate. Inflammation is often asymptomatic, especially in the gut and prostate. The HLA-B*27 allele group, which presents intracellular peptides to CD8+ T cells, is by far the strongest risk factor for spondyloarthritis. The precise mechanisms and antigens remain unknown. In 1959, Catterall and King advanced a novel hypothesis explaining the etiology of spondyloarthritis: an as-yet-unrecognized sexually acquired microbe would be causing all spondyloarthritis types, including acute anterior uveitis. Recent studies suggest an unrecognized sexually acquired fungal infection may be involved in prostate cancer and perhaps multiple sclerosis. This warrants reanalyzing the Catterall-King hypothesis based on the current literature. In the last decade, many links between spondyloarthritis and fungal infections have been found. Antibodies against the fungal cell wall component mannan are elevated in spondyloarthritis. Functional polymorphisms in genes regulating the innate immune response against fungi have been associated with spondyloarthritis (CARD9 and IL23R). Psoriasis and inflammatory bowel disease, two common comorbidities of spondyloarthritis, are both strongly associated with fungi. Evidence reviewed here lends credence to the Catterall-King hypothesis and implicates a common fungal etiology in prostate cancer, benign prostatic hyperplasia, multiple sclerosis, psoriasis, inflammatory bowel disease, and spondyloarthritis. However, the evidence available at this time is insufficient to definitely confirm this hypothesis. Future studies investigating the microbiome in relation to these conditions should screen specimens for fungi in addition to bacteria. Future clinical studies of spondyloarthritis should consider antifungals which are effective in psoriasis and multiple sclerosis, such as dimethyl fumarate and nystatin.

Recent advances and future directions in understanding and treating Chlamydia-induced reactive arthritis

INTRODUCTION

Reactive arthritis (ReA) is an inflammatory disease that can follow gastrointestinal or genitourinary infections. The primary etiologic agent for post-venereal ReA is the bacterium Chlamydia trachomatis; its relative, C pneumoniae, has also been implicated in disease induction although to a lesser degree. Studies have indicated that the arthritis is elicited by chlamydiae infecting synovial tissue in an unusual biologic state designated persistence. We review clinical aspects, host-pathogen interactions, and treatments for the disease. Areas covered: We briefly discuss both the historic and,more extensively, the current medical literature describing ReA, and we provide a discussion of the biology of the chlamydiae as it relates to elicitation of the disease. A summary of clinical aspects of Chlamydia-induced ReA is included to give context for approaches to treatment of the arthritis. Expert commentary: Basic research into the biology and host-pathogen interactions characteristic of C trachomatis has provided a wealth of information that underlies our current understanding of the pathogenic processes occurring in the ReA synovium. Importantly, a promising approach to cure of the disease is at hand. However, both basic and clinical research into Chlamydia-induced ReA has lagged over the last 5 years, including required studies relating to cure of the disease.

The incidence of sexually acquired reactive arthritis: a systematic literature review

Reactive arthritis (ReA) is an inflammatory spondyloarthritis occurring after infection at a distant site. Chlamydia trachomatis is proposed to be the most common cause of ReA, yet the incidence of sexually acquired ReA (SARA) has not been well established. We therefore carried out a systematic literature review to collate and critically evaluate the published evidence regarding the incidence of SARA. MEDLINE and EMBASE databases were searched using free-text and MeSH terms relating to infection and ReA. The title and abstract of articles returned were screened independently by two reviewers and potentially relevant articles assessed in full. Data was extracted from relevant articles and a risk of bias assessment carried out using a validated tool. Heterogeneity of study methodology and results precluded meta-analysis. The search yielded a total of 11,680 articles, and a further 17 were identified from review articles. After screening, 55 papers were assessed in full, from which 3 met the relevant inclusion criteria for the review. The studies reported an incidence of SARA of 3.0-8.1 % and were found to be of low to moderate quality. More studies are required to address the lack of data regarding the incidence of SARA. Specific and sensitive classification criteria must be developed in order for consistent classification and valid conclusions to be drawn. In clinical practice, it is recommended clinicians discuss the possibility of ReA developing at the time of STI diagnosis and to encourage patients to return if they experience any relevant symptoms.

Sexually acquired reactive arthritis

Sexually acquired reactive arthritis (SARA) may present acutely to general physicians. It is important to consider the condition and to identify key features in the history and examination so that appropriate investigations are taken and optimum treatment is given. Involvement of relevant specialists in the management is essential and where sexually transmitted infections are identified, partner notification is required.

Reactive arthritis at the Sydney Sexual Health Centre 1992-2012: declining despite increasing chlamydia diagnoses

Reactive arthritis is an under-studied complication of genital Chlamydia trachomatis infection (chlamydia). We assessed trends and risk factors for reactive arthritis in a large urban sexual health clinic. Using a case-control design, data on reactive arthritis cases and controls at the Sydney Sexual Health Centre over the period 1992-2012 were extracted and multivariate analyses were performed. Trend analyses were performed on reactive arthritis diagnoses. Over the 1992-2012 study period, 85 reactive arthritis cases were diagnosed at Sydney Sexual Health Centre. The rate of reactive arthritis diagnoses decreased over time (23 in 1992-1996 to one in 2007-2011 and none in 2012), while chlamydia diagnoses increased (770 in 1992-1996 to 2257 in 2007-2011). In multivariate analysis, factors independently associated with a reactive arthritis diagnosis were: being male (adjusted odds ratio [aOR] 3.27; 95% confidence interval [CI] 1.04-10.32; p = 0.043) or born overseas (aOR 2.69; 95% CI 1.27-5.70; p = 0.010), while a past sexually transmitted infection other than chlamydia or non-gonococcal urethritis was protective (aOR 0.21; 95% CI 0.10-0.45; p < 0.001). Reactive arthritis was not associated with current or recent chlamydia infection (p = 0.184) but was marginally associated with past non-gonococcal urethritis (p = 0.080). This study found a decline in reactive arthritis diagnoses despite an increase in chlamydia diagnoses.

High Chlamydia Burden Promotes Tumor Necrosis Factor-Dependent Reactive Arthritis in SKG Mice

OBJECTIVE

Chlamydia trachomatis is a sexually transmitted obligate intracellular pathogen that causes inflammatory reactive arthritis, spondylitis, psoriasiform dermatitis, and conjunctivitis in some individuals after genital infection. The immunologic basis for this inflammatory response in susceptible hosts is poorly understood. As ZAP-70(W163C) -mutant BALB/c (SKG) mice are susceptible to spondylo-arthritis after systemic exposure to microbial β-glucan, we undertook the present study to compare responses to infection with Chlamydia muridarum in SKG mice and BALB/c mice.

METHODS

After genital or respiratory infection with C muridarum, conjunctivitis and arthritis were assessed clinically, and eye, skin, and joint specimens were analyzed histologically. Chlamydial major outer membrane protein antigen-specific responses were assessed in splenocytes. Treg cells were depleted from FoxP3-DTR BALB/c or SKG mice, and chlamydial DNA was quantified by polymerase chain reaction.

RESULTS

Five weeks after vaginal infection with live C muridarum, arthritis, spondylitis, and psoriasiform dermatitis developed in female SKG mice, but not in BALB/c mice. Inflammatory bowel disease did not occur in mice of either strain. The severity of inflammatory disease was correlated with C muridarum inoculum size and vaginal burden postinoculation. Treatment with combination antibiotics starting 1 day postinoculation prevented disease. Chlamydial antigen was present in macrophages and spread from the infection site to lymphoid organs and peripheral tissue. In response to chlamydial antigen, production of interferon-γ and interleukin-17 was impaired in T cells from SKG mice but tumor necrosis factor (TNF) responses were exaggerated, compared to findings in T cells from BALB/c mice. Unlike previous observations in arthritis triggered by β-glucan, no autoantibodies developed. Accelerated disease triggered by depletion of Treg cells was TNF dependent.

CONCLUSION

In the susceptible SKG strain, Chlamydia-induced reactive arthritis develops as a result of deficient intracellular pathogen control, with antigen-specific TNF production upon dissemination of antigen, and TNF-dependent inflammatory disease.

Role of genetics in infection-associated arthritis

Genetic discoveries in arthritis and their associated biological pathways spanning the innate and adaptive immune system demonstrate the strong association between susceptibility to arthritis and control of exogenous organisms. The canonical theory of the aetiology of immune-mediated arthritis and other immune-mediated diseases is that the introduction of exogenous antigenic stimuli to a genetically susceptible host sets up the environment for an abnormal immune response manifesting as disease. A disruption in host-microbe homeostasis driven by disease-associated genetic variants could ultimately provide the source of exogenous antigen triggering disease development. We discuss genetic variants impacting the innate and adaptive arms of the immune system and their relationship to microbial control and arthritic disease. We go on to consider the evidence for a relationship between HLA-B27, infection and arthritis, and then emerging evidence for an interaction between microbiota and rheumatoid arthritis.

Immunopathogenesis of reactive arthritis: Role of the cytokines

Reactive arthritis (ReA), also known as sterile postinfectious arthritis, belongs to the group of related arthropathies known as spondyloarthritis (SpA). ReA can arise 1-4 wk after a gastrointestinal or genitourinary infection, but once arthritis develops, the microorganism is not found in the joint. The classical microbes associated with ReA development include Gram-negative aerobic or microaerophilic bacteria containing LPS in their outer membrane. The immunopathogenic mechanisms involved in ReA development are still unknown. A hypothesis suggested that the bacteria probably persist outside the joint, at sites such as gut mucosa or lymph nodes, and bacterial antigens might then be transported to the joints. On the other hand, an altered immune response and the unbalanced production of cytokines have been reported in subjects with ReA. Currently, there is increased evidence to suggest that both mechanisms would operate in the immunopathogenesis of ReA. In this review we highlight recent advances on the role of cytokines in the ReA. Particularly, we discuss the roles of some pro- and anti-inflammatory cytokines involved in the immunopathogenesis of ReA.

Attack Rate of Chlamydia-induced Reactive Arthritis and Effect of the CCR5-Delta-32 Mutation: A Prospective Analysis

Objective.

Factors that predispose patients to Chlamydia-induced reactive arthritis (CiReA) are poorly defined. Data indirectly suggest chemokine receptor-5 (CCR5)-delta-32 mutation might play a role in CiReA. We investigated the attack rate of CiReA and we hypothesized that the CCR5-delta-32 allele may modulate disease susceptibility.

Methods.

Patients who tested positive for Chlamydia trachomatis after either (1) symptoms of an acute venereal disease or (2) sexual contact with an individual known to be positive for the same organism were followed in a prospective fashion. All patients were contacted at Week 6 after their acute infection and queried for symptoms of CiReA. Patients who had new-onset symptoms suggestive of CiReA were followed at Weeks 12, 26, and 52. All subjects were tested for CCR5-delta-32 mutation.

Results.

A total of 365 study participants were enrolled, with average age 24.4 years, 201 men (55%) and 164 women (45%). We followed up with 149 patients (41%) at Week 6. Twelve of 149 participants (8.1%) had symptoms suggestive of CiReA at Week 6. None of these 12 patients was positive for the CCR5-delta-32 mutation. Of the 12 patients that had symptoms at Week 6, we were able to follow up with 7 through Week 52. All 7 had complete resolution of their symptoms by Week 26. Overall, 25/365 (6.8%) subjects were positive for the CCR5-delta-32 mutation.

Conclusion.

The attack rate of CiReA in our study was higher than previously reported, but the CCR5-delta-32 mutation does not seem to play a role in CiReA disease susceptibility.

The molecular basis for disease phenotype in chronic Chlamydia-induced arthritis

Genital Chlamydia trachomatis infections can elicit an inflammatory arthritis in some individuals, and recent surprising studies have demonstrated that only ocular (trachoma) strains, not genital strains, of the organism are present in the synovial tissues of patients with the disease. This observation suggests an explanation for the small proportion of genitally-infected patients who develop Chlamydia-induced arthritis. Other recent studies have begun to identify the specific chlamydial gene products that elicit the synovial inflammatory response during both active and quiescent disease, although much more study will be required to complete the understanding of that complex process of host-pathogen interaction. Several newly developed experimental methods and approaches for study of the process will enable identification of new therapeutic targets, and possibly strategies for prevention of the disease altogether.

Treating reactive arthritis: insights for the clinician

THERE ARE TWO MAIN FORMS OF REACTIVE ARTHRITIS (REA): postvenereal and postdysentery. Chlamydia trachomatis (Ct) is the major causative organism of the postvenereal type; Salmonella, Shigella, Campylobacter, and Yersinia are the major triggers for the postenteric type. All of these causative organisms have been shown to traffic to the synovium in affected individuals. However, one important difference is that the chlamydial organisms have been shown to be viable, whereas, in general, the postenteric organisms are not. Although estimates vary widely, it is felt that 30-50% of all cases of ReA become chronic and the remainder resolve spontaneously within weeks to months. These important differences need to be considered when reviewing the available therapeutic outcomes data. There is a relative paucity of prospective clinical trial data assessing various treatment strategies. A large breadth of clinical experience demonstrates that nonsteroidal anti-inflammatory drugs (NSAIDs) and corticosteroids are efficacious, but there have only been two rather small trials assessing NSAIDs and none with corticosteroids. Disease modifying drugs are sometimes utilized in more severe or chronic cases, but only sulfasalazine (SSZ) has been studied. Anti-tumor necrosis factor (TNF) therapy has proved remarkably efficacious with other types of spondyloarthritides, but there is very little data to support their use in ReA; theoretical concerns also exist with this drug class in ReA, specifically. Finally, antibiotics have been studied in several trials. A thorough analysis of these trials reveals equivocal results with a possible particular benefit in postchlamydial ReA. These data are reviewed with an emphasis on postchlamydial and postenteric ReA.

Chlamydia-induced ReA: immune imbalances and persistent pathogens

Reactive arthritis (ReA), an inflammatory arthritic condition that is commonly associated with Chlamydia infections, represents a significant health burden, yet is poorly understood. The enigma of this disease is reflected in its problematic name and in its ill-defined pathogenesis. The existence of persistent pathogens in the arthritic joint is acknowledged, but their relevance remains elusive. Progress is being made in understanding the underlying mechanisms of ReA, whereby an imbalance between type 1 and type 2 immune responses seems to be critical in determining susceptibility to disease. Such an imbalance occurs prior to the initiation of an adaptive immune response, suggesting that innate cellular and molecular mechanisms in ReA should be prioritized as fruitful areas for investigation.

Reactive arthritis

Reactive arthritis (ReA) can be defined as the development of sterile inflammatory arthritis as a sequel to remote infection, often in the gastrointestinal or urogenital tract. Although no generally agreed-upon diagnostic criteria exist, the diagnosis is mainly clinical, and based on acute oligoarticular arthritis of larger joints developing within 2-4 weeks of the preceding infection. According to population-based studies, the annual incidence of ReA is 0.6-27/100,000. In addition to the typical clinical picture, the diagnosis of ReA relies on the diagnosis of the triggering infection. Human leucocyte antigen (HLA)-B27 should not be used as a diagnostic tool for a diagnosis of acute ReA. In the case of established ReA, prolonged treatment of Chlamydia-induced ReA may be of benefit, not only in the case of acute ReA but also in those with chronic ReA or spondylarthropathy with evidence of persisting chlamydia antigens in the body. In other forms of ReA, there is no confirmed evidence in favour of antibiotic therapy to shorten the duration of acute arthritis. The outcome and prognosis of ReA are best known for enteric ReA, whereas studies dealing with the long-term outcome of ReA attributable to Chlamydia trachomatis are lacking.

Bacterial agents in spondyloarthritis: a destiny from diversity?

The spondyloarthritides (SpAs) are a group of diseases that share clinical, radiographic and laboratory features; these arthritides also display a tendency for family aggregation. Given the intimate relationship that these types of arthritis share, it suggests that the SpAs might share a common aetiology. Of all the SpAs, the role of bacteria is most clearly defined in reactive arthritis. Tremendous recent insights into the pathophysiology of reactive arthritis have been made, demonstrating that the causative bacteria play a much more complex role than previously thought. The bacteria that are proven to cause reactive arthritis, one of the five types of SpA, will be reviewed and their role in the pathophysiology of reactive arthritis will be examined. The speculative data suggesting links between various other bacteria and the other types of SpAs will be critically analysed. Although these data are not definitive, when viewed using the paradigm that the SpAs might actually represent a common end point from several diverse starting points, they are provocative, suggesting that bacteria might, indeed, be aetiological for the entire group of SpAs.

Experimental modeling of viral diseases of the locomotor system

Dissemination of infectious inflammation was studied in experimental influenza and acute and chronic herpesvirus infections. The possibility of articular involvement into the infectious process was evaluated. Pathomorphological signs of changes in the articular tissue confirmed the effects of these viruses on the locomotor pathology. Results of virus infection simulation in experimental animals suggest this model for studies of the pathogenesis of diseases of viral etiology (including those with articular involvement) in humans.

Reactive arthritis: clinical aspects and medical management

Reactive arthritis (ReA) is an inflammatory arthritis that arises after certain gastrointestinal or genitourinary infections, representing a classic interplay between host and environment. It belongs to the group of arthritidies known as the spondyloarthropathies. The classic syndrome is a triad of symptoms, including the urethra, conjunctiva, and synovium; however, the majority of patients do not present with this triad. Diagnostic criteria for ReA exist, but data suggest new criteria are needed. Epidemiologic and prospective studies have been difficult to perform because of over-reliance on the complete classic triad of symptoms and the different terms and eponyms used. Studies assessing various treatment strategies are ongoing.

Chlamydiae as etiologic agents in chronic undifferentiated spondylarthritis

OBJECTIVE

The majority of patients with Chlamydia-induced reactive arthritis do not present with the classic triad of arthritis, conjunctivitis/iritis, and urethritis. Moreover, acute chlamydial infections are often asymptomatic. The aim of the present study was to assess the prevalence of synovial Chlamydia trachomatis and Chlamydia pneumoniae infections in patients with chronic undifferentiated spondylarthritis (uSpA).

METHODS

Study patients met the European Spondylarthropathy Study Group criteria for SpA, without evidence of ankylosing spondylitis, psoriasis, inflammatory bowel disease, or preceding dysentery. Symptoms were present for >or=6 months. Each patient underwent a synovial biopsy; tissue and concomitantly obtained peripheral blood mononuclear cells (PBMCs) were analyzed by polymerase chain reaction (PCR) for C trachomatis and C pneumoniae DNA. Other data collected on the day of the biopsy included standard demographic information and medical history, including any known history of C trachomatis or C pneumoniae. Physical examination (including joint count, evaluation for dactylitis and/or enthesitis, and skin examination) and HLA-B27 typing were performed. Synovial tissue (ST) samples from 167 patients with osteoarthritis (OA) were used as controls.

RESULTS

Twenty-six patients met the entry criteria and underwent synovial biopsy (25 knee, 1 wrist). Sixteen of them (62%) were positive for C trachomatis and/or C pneumoniae DNA (10 for C trachomatis, 4 for C pneumoniae, and 2 for both). PCR analysis of ST revealed the presence of Chlamydia significantly more frequently in patients with uSpA than in OA controls (P<0.0001). No specific clinical characteristics differentiated Chlamydia-positive from Chlamydia-negative patients. PBMCs from 4 of the 26 uSpA patients (15%) were positive for Chlamydia, and Chlamydia was found in ST from 2 of these 4 patients. No significant correlation between PCR positivity and HLA-B27 positivity was found.

CONCLUSION

The frequency of Chlamydia-positive ST samples, as determined by PCR, was found to be significantly higher in patients with uSpA than in patients with OA. Our results suggest that in many patients with uSpA, chlamydial infection, which is often occult, may be the cause.

Reactive arthritis: a review

This review article summarizes the available literature on adolescent reactive arthritis. A review of the pathophysiology, diagnosis, and treatment guidelines will be helpful to better diagnose and treat reactive arthritis.

Reactive arthritis: defined etiologies, emerging pathophysiology, and unresolved treatment

ReA is unique in that it is one of the few disease states of which there is a known trigger. This insight into disease initiation has led to great advances in the pathophysiology. Despite this detailed knowledge, the proper treatment remains elusive. In the years to come it is possible that the specific treatment will be dictated by the triggering microbe.

HLA-B27-associated reactive arthritis: pathogenetic and clinical considerations

Current evidence supports the concept that reactive arthritis (ReA) is an immune-mediated synovitis resulting from slow bacterial infections and showing intra-articular persistence of viable, non-culturable bacteria and/or immunogenetic bacterial antigens synthesized by metabolically active bacteria residing in the joint and/or elsewhere in the body. The mechanisms that lead to the development of ReA are complex and basically involve an interaction between an arthritogenic agent and a predisposed host. The way in which a host accommodates to invasive facultative intracellular bacteria is the key to the development of ReA. The details of the molecular pathways that explain the articular and extra-articular manifestations of the disease are still under investigation. Several studies have been done to gain a better understanding of the pathogenesis of ReA; these constitute the basis for a more rational therapeutic approach to this disease.

From farm to table to brain: foodborne pathogen infection and the potential role of the neuro-immune-endocrine system in neurotoxic sequelae

The American diet is among the safest in the world; however, diseases transmitted by foodborne pathogens (FBPs) still pose a public health hazard. FBPs are the second most frequent cause of all infectious illnesses in the United States. Numerous anecdotal and clinical reports have demonstrated that central nervous system inflammation, infection, and adverse neurological effects occur as complications of foodborne gastroenteritis. Only a few well-controlled clinical or experimental studies, however, have investigated the neuropathogenesis. The full nature and extent of neurological involvement in foodborne illness is therefore unclear. To our knowledge, this review and commentary is the first effort to comprehensively discuss the issue of FBP induced neurotoxicity. We suggest that much of this information supports the role of a theoretical model, the neuro-immune-endocrine system, in organizing and helping to explain the complex pathogenesis of FBP neurotoxicity.

Randomised, blinded, placebo controlled trial of doxycycline for chronic seronegative arthritis

OBJECTIVE

To determine whether long term doxycycline improves symptoms in patients with chronic seronegative or reactive arthritis.

METHODS

A randomised, triple blind, controlled clinical trial of three months' treatment with doxycycline or placebo of patients with chronic reactive or seronegative arthritis was conducted. The primary study end points were three month pain and functional status measured by a self administered Arthritis Impact Measurement Scales version 2 (AIMS2) quality of life questionnaire. Secondary end points were pain and functional status at 6-12 months, three month rheumatologist assessed joint count, pain, and arthritis activity, and treatment efficacy in those with previous exposure to chlamydia.

RESULTS

Of 60 patients randomly allocated to receive doxycycline or placebo, results from 37 were evaluable at three months. Groups were well balanced for major prognostic variables. Doxycycline had no detectable effect at three months on pain change scores (mean difference 1.5, 95% CI -1.2 to 4.2, p=0.25) or composite functional change scores (mean difference 0.8, 95% CI -5.6 to 7.1, p=0.81). Furthermore, there were no differences in secondary study end points, and no apparent treatment effect in patients with previous chlamydia infection.

CONCLUSION

Three months' treatment with doxycycline did not improve pain or functional status in patients with chronic reactive or seronegative arthritis.

Male sex predominance in Chlamydia trachomatis sexually acquired reactive arthritis: are women more protected by anti-chlamydia antibodies?

OBJECTIVE

To determine whether the humoral anti-chlamydia antibody response might be related to the ineffective bacterial elimination seen in patients with Chlamydia trachomatis reactive arthritis, particularly in men, who have a higher prevalence of the disease than women.

METHODS

The number and specificity of the antibody responses to 27 different C trachomatis antigens were determined by western blots in serum samples from patients with C trachomatis urogenital infection, with and without reactive arthritis, with a special regard to the sex of the patients.

RESULTS

Patients with reactive arthritis had antibodies to significantly fewer chlamydia antigens than those with urethritis only. Antibodies from men recognised significantly fewer antigens than antibodies from women. The IgA class antibodies were slightly more relevant than those of the IgG class for differentiation of patients with reactive arthritis from those with uncomplicated genitourinary infection.

CONCLUSIONS

In patients with acute C trachomatis infection the development of reactive arthritis may be related, particularly in men, to a deficient humoral response, to antigens which perhaps play a part in the clearance of the bacteria. Men who cannot generate antibodies to a large number of antigens may be less able to contain the local infection, allowing a wide systemic dissemination of the organisms to the joints.

Frequency of triggering bacteria in patients with reactive arthritis and undifferentiated oligoarthritis and the relative importance of the tests used for diagnosis

OBJECTIVE

Reactive arthritis (ReA) triggered by Chlamydia trachomatis or enteric bacteria such as yersinia, salmonella, Campylobacter jejuni, or shigella is an important differential diagnosis in patients presenting with the clinical picture of an undifferentiated oligoarthritis (UOA). This study was undertaken to evaluate the best diagnostic approach.

PATIENTS AND METHODS

52 patients with ReA, defined by arthritis and a symptomatic preceding infection of the gut or the urogenital tract, and 74 patients with possible ReA, defined by oligoarthritis without a preceding symptomatic infection and after exclusion of other diagnoses (UOA), were studied. The following diagnostic tests were applied for the identification of the triggering bacterium: for yersinia induced ReA-stool culture, enzyme immunoassay (EIA), and Widal's agglutination test for detection of antibodies to yersinia; for salmonella or campylobacter induced ReA-stool culture, EIA for the detection of antibodies to salmonella and Campylobacter jejuni; for infections with shigella-stool culture; for infections with Chlamydia trachomatis-culture of the urogenital tract, microimmunofluorescence and immunoperoxidase assay for the detection of antibodies to Chlamydia trachomatis.

RESULTS

A causative pathogen was identified in 29/52 (56%) of all patients with ReA. In 17 (52%) of the patients with enteric ReA one of the enteric bacteria was identified: salmonella in 11/33 (33%) and yersinia in 6/33 (18%). Chlamydia trachomatis was the causative pathogen in 12/19 (63%) of the patients with urogenic ReA. In patients with the clinical picture of UOA a specific triggering bacterium was also identified in 35/74 (47%) patients: yersinia in 14/74 (19%), salmonella in 9/74 (12%), and Chlamydia trachomatis in 12/74 (16%).

CONCLUSIONS

Chlamydia trachomatis, yersinia, and salmonella can be identified as the causative pathogen in about 50% of patients with probable or possible ReA if the appropriate tests are used.

Screening for chlamydial infection

OBJECTIVES

To examine data on the effectiveness of screening for chlamydial infection by a physician or other health care professional. Specifically, we examine the evidence that early treatment of chlamydial infection improves health outcomes, as well as evidence of the effectiveness of screening strategies in nonpregnant women, pregnant women, and men, and the accuracy of tests used for screening. This review updates the literature since the last recommendation of the U.S. Preventive Services Task Force published in 1996.

SEARCH STRATEGY

We searched the topic of chlamydia in the MEDLINE, HealthSTAR, and Cochrane Library databases from January 1994 to July 2000, supplemented by reference lists of relevant articles and from experts in the field. Articles published prior to 1994 and research abstracts were cited if particularly important to the key questions or to the interpretation of included articles.

SELECTION CRITERIA

A single reader reviewed all English abstracts. Articles were selected for full review if they were about Chlamydia trachomatis genitourinary infections in nonpregnant women, pregnant women, or men and were relevant to key questions in the analytic framework. Investigators read the full-text version of the retrieved articles and applied additional eligibility criteria. For all topics, we excluded articles if they did not provide sufficient information to determine the methods for selecting subjects and for analyzing data.

DATA COLLECTION AND ANALYSIS

We systematically reviewed three types of studies about screening in nonpregnant women that relate to three key questions: (1) studies about the effectiveness of screening programs in reducing prevalence rates of infection, (2) studies about risk factors for chlamydial infection in women, and (3) studies about chlamydial screening tests in women. Our search found too few studies on pregnant women to systematically review, although pertinent studies are described. We systematically reviewed two types of studies about screening in men: (1) studies about prevalence rates and risk factors for chlamydial infection in men and (2) studies about chlamydial screening tests in men.

MAIN RESULTS

Nonpregnant women. The results of a randomized controlled trial conducted in a large health maintenance organization indicate that screening women selected by a set of risk factors reduces the incidence of pelvic inflammatory disease (PID) over a 1-year period. Changes in population prevalence rates have not been well documented because few studies have employed a representative population sample. Age continues to be the best predictor of chlamydial infection in women, with most studies evaluating cut-offs at age younger than 25 years. Other risk factors may be useful predictors, but these are likely to be population specific. To determine the accuracy of screening tests for women, we retrieved and critically reviewed 34 articles on test performance. Results indicate that endocervical swab specimens and first-void urine specimens have similar performance when using DNA amplification tests and have better sensitivity than endocervical culture. Recurrent chlamydial infections in women have been associated with increased risks for PID and ectopic pregnancies. Pregnant women. The Second Task Force recommendations for screening pregnant women were based on two major studies demonstrating improved pregnancy outcomes following treatment of chlamydial infection. We identified no recent studies on this topic in our literature search. Very few studies describe risk factors for chlamydial infection in pregnant women. Nonculture testing techniques appear to perform well in pregnant women, although studies are limited. Men. No studies described the effectiveness of screening or early treatment for men in reducing transmission to women or in preventing acute infections or complications in men. Studies of prevalence rates and risk factors for chlamydial infection in men are limited. Age lower than 25 years is the strongest known risk factor cited so far. Results of urethral swab specimens compared to first-void urine specimens were similar for DNA amplification tests. DNA amplification techniques are more sensitive than culture.

CONCLUSIONS

Screening women for Chlamydia trachomatis reduces the incidence of PID, and it is associated with reductions in prevalence of infection in uncontrolled studies. No studies were found to determine whether screening asymptomatic men would reduce transmission or prevent acute infections or complications. Age is the strongest risk factor for men and women. A variety of tests can detect chlamydial infection with acceptable sensitivity and specificity, including new DNA amplification tests that use either endocervical swabs in women, urethral swabs in men, or first-void urine specimens from men and women.

IL10.G microsatellites mark promoter haplotypes associated with protection against the development of reactive arthritis in Finnish patients

OBJECTIVE

To investigate the association of microsatellites and single-nucleotide promoter polymorphisms (SNPs) in the gene for the cytokine interleukin-10 (IL-10) with susceptibility to and outcome of reactive arthritis (ReA).

METHODS

From genomic DNA, IL-10 microsatellites G and R and IL-10 promoter polymorphisms at positions -1087 and -524 were typed by polymerase chain reaction, automated fragment length analysis, and restriction fragment digestion in 85 Finnish patients with ReA and 62 HLA-B27-positive Finnish controls. ReA patients had been followed up for 20 years. Genotypes and haplotypes of IL-10 were correlated with distinct features of the disease course, such as triggering agent, chronic arthritis, development of ankylosing spondylitis, and other chronic features.

RESULTS

There was a significant decrease in the promoter alleles G12 (allele frequency 0.206 versus 0.033; corrected P < 0.001, odds ratio 0.14) and G10 (0.183 versus 0.092; P < 0.05, odds ratio 0.44) in the ReA group compared with the HLA-B27-positive controls. Chronic arthritis developed significantly more frequently in the B27-positive subjects than in the B27-negative subjects (P < 0.05) as well as in patients with [corrected] the IL10.G8 allele. No associations were observed for either SNP or for the IL10.R microsatellite polymorphism.

CONCLUSION

IL10.G12 and G10 microsatellite alleles show a strong protective effect against the development of ReA in Finnish subjects. Since these polymorphic markers themselves do not have direct functional implications, they most likely mark promoter haplotypes with distinct functional properties, suggesting that differential production of IL-10 is an important susceptibility factor for the development of ReA.

The spectrum of skin, mucosa and other extra-articular manifestations

The seronegative spondyloarthropathies appear to be the genetically predisposed host's clinical expression to acute, subacute or chronic reaction to the invasion by environmental microorganisms. In the ensuing days or weeks, depending on the infectious load, clinical manifestations may occur ranging from constitutional complaints such as fever, to a variety of symptoms and/or signs related to the portal of entry-intestinal, genitourinary or respiratory. Within weeks or months, the initial or other target organs, such as the mucocutaneous, ocular and cardiovascular systems, may develop an acute reaction of greater or lesser specificity regarding the triggering agent (oral ulcers, circinate balanitis, erythema nodosum, acute anterior uveitis, pericarditis, heart blocks). Lastly, many years later, a minority of patients, probably those with a large genetic component, exhibit a spectrum of clinical manifestations related to those organs, with a chronic or recurrent course. Acute clinical manifestations--reactive arthritis--are prominent in the initial phase of the clinical spectrum, while chronic manifestations--ankylosing spondylitis--are seen at the other end of the spectrum.

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.