The use of a low starch diet in the treatment of patients suffering from ankylosing spondylitis

Current insights on the roles of gut microbiota in inflammatory bowel disease-associated extra-intestinal manifestations: pathophysiology and therapeutic targets

Inflammatory bowel disease (IBD) is a chronic, recurrent inflammatory disease of the gastrointestinal tract. In addition to digestive symptoms, patients with IBD may also develop extra-intestinal manifestations (EIMs), the etiology of which remains undefined. The gut microbiota has been reported to exert a critical role in the pathogenesis of IBD, with a similar pattern of gut dysbiosis observed between patients with IBD and those with EIMs. Therefore, it is hypothesized that the gut microbiota is also involved in the pathogenesis of EIMs. The potential mechanisms are presented in this review, including: 1) impaired gut barrier: dysbiosis induces pore formation in the intestinal epithelium, and activates pattern recognition receptors to promote local inflammation; 2) microbial translocation: intestinal pathogens, antigens, and toxins translocate via the impaired gut barrier into extra-intestinal sites; 3) molecular mimicry: certain microbial antigens share similar epitopes with self-antigens, inducing inflammatory responses targeting extra-intestinal tissues; 4) microbiota-related metabolites: dysbiosis results in the dysregulation of microbiota-related metabolites, which could modulate the differentiation of lymphocytes and cytokine production; 5) immunocytes and cytokines: immunocytes are over-activated and pro-inflammatory cytokines are excessively released. Additionally, we summarize microbiota-related therapies, including probiotics, prebiotics, postbiotics, antibiotics, and fecal microbiota transplantation, to promote better clinical management of IBD-associated EIMs.

Patients with radiographic axial spondylarthritis have an impaired dietary intake-a cross-sectional study with matched controls from northern Sweden

BACKGROUND

Radiographic axial spondyloarthritis (r-axSpA) is one of the most common chronic inflammatory rheumatic diseases, affecting about 0.2% of the Swedish population. Adequate nutritional intake is essential for maintaining physiological functions. A poor diet increases the risk of developing conditions such as obesity, osteoporosis, and/or atherosclerosis. Diet quality is also theorized to affect systemic inflammation. Dietary habits in patients with r-axSpA are largely unknown. The aims of this study were to assess dietary nutrient intake in r-axSpA patients and examine whether it differs compared to persons without r-axSpA.

METHODS

r-axSpA patients (modified NY criteria) at the rheumatology clinic in Region Västerbotten, northern Sweden, were invited to take part in the Backbone study which investigates disease severity and comorbidities. In total, 155 patients were included. Nutritional intake was assessed by the semi-quantitative food frequency questionnaire MiniMeal-Q. Controls were collected from the Swedish CArdioPulmonary bioImage Study (n = 30,154), a study that invited participants 50-64 years of age by random selection from the Swedish population register. Out of the 155 r-axSpA patients, 81 were in the same age span. Four controls were identified for each patient, matched on age (± 1 year), sex, and geographic location. Data on dietary intake was available for 319 controls. Statistical comparisons of dietary intake between patients with r-axSpA and controls were done by exact conditional logistic regression analysis, adjusted for country of birth, educational level, single household, weight, smoking status, and energy intake.

RESULTS

Patients had a comparatively significantly higher energy intake from carbohydrates, a lower fiber density, and a lower intake of marine omega-3 fatty acids. Furthermore, intake of vitamins D, E, and K as well as selenium, folate, calcium, magnesium, phosphorus, potassium, vitamin A, and β-carotene (a precursor of vitamin A and marker of vegetable and fruit intake) was significantly lower among patients compared to controls.

CONCLUSIONS

Our results suggest that r-axSpA patients have an impaired dietary intake. Notably, intake was lower in several nutrients theorized to have anti-inflammatory properties (fiber density, marine-omega-3 fatty acids, vitamin D, and selenium). We further propose that nutrition screening might be incorporated into the management of r-axSpA patients.

Role of the microbiome and its metabolites in ankylosing spondylitis

Ankylosing spondylitis (AS), a chronic condition that commonly influences the spine and sacroiliac joints, usually progresses to stiffness and progressive functional limitation. Its fundamental etiology and pathogenesis are likely multifactorial and remain elusive. As environmental factors, gut microbiota performs critical functions in the pathogenesis of AS through various mechanisms, including interacting with genes, enhancing intestinal permeability, activating the gut mucosa immune system, and affecting the intestinal microbiota metabolites. This review provides an overview of recent advances in investigating gut microbiota in AS pathogenesis and discusses potential methods for future therapeutic intervention.

Spondyloarthritis: How far are we from precision medicine?

Spondyloarthritis (SpA) is a family of heterogenous diseases consisting of different phenotypes. The exact disease mechanism remains unclear but evidence shows the complex pathophysiology with interplay between genome, microbiome, and immunome. Biologic DMARDs have markedly improved patients' disease control and quality of life. However, treatment response varies among patients. There is a growing need to identify biomarkers for the diagnosis, prognosis, prevention, and treatment of SpA. Genomic studies have been the research focus in the past two decades and have identified important genes involved in SpA. In recent years, emerging evidence supports the link between gut and joint inflammation in SpA, in which the role of gut microbiome in SpA is of great interest. Herein, potential genetic and gut microbial biomarkers for predicting treatment response are discussed. Novel strategies targeting dysbiosis in SpA are also summarized. These results represent a significant step toward precision medicine for patients with SpA.

Nutrition in Ankylosing Spondyloarthropathies and Related Immune-Mediated Disorders

Recent research on the pathogenesis of spondyloarthritis and related immune-mediated diseases associated with human leukocyte antigen class I molecule B27 (HLA-B27) has led to significant progress in terms of management and prognosis, with multiple treatments being constantly evaluated and implemented. Correlations between the genetic background of spondyloarthritis and inflammatory bowel diseases and the inflammatory processes involving gut microbiota have been established. This knowledge has allowed progress in pharmacological therapy. The role of diet in the pathogenesis and treatment of diseases pertaining to the HLA-B27 spectrum is of great significance, considering possible future applications in individualized medicine. Diet impacts the composition of gut microbiota, representing a substrate for the synthesis of metabolites affecting the mucosal immune system. Certain pro-inflammatory mediators, such as emulsifiers and microparticles, induce a more profound cytokine response, promoting inflammation. Numerous diets, including the low-starch diet, the Mediterranean diet, diets with low contents of fermentable oligosaccharides, disaccharides, monosaccharides and polyols (low-FODMAP diets), gluten-free diets and fasting, have been analysed and correlated with patients’ symptomatology and dietary adherence. The aim of this review is to provide an extensive perspective on the diets available to patients with spondyloarthritis and related immune-mediated disorders.

Successful treatment of ankylosing spondylitis with alternative and complementary medicine withdrawal of adalimumab treatment

BACKGROUND AND PURPOSE

Current treatment strategies for ankylosing spondylitis (AS) include adalimumab and other biological drugs. However, treatment failures and side effects are commonly observed. This report documents the successful use of supplements and dietary changes to treat a patient with AS after cessation of adalimumab therapy.

PATIENT PRESENTATION

A 38-year-old human leukocyte antigen B27 positive female patient with AS showed no improvement when treated with a non-steroidal anti-inflammatory drug. The patient then began adalimumab therapy with some success; however, after nine months, she developed a disseminated and refractory Molluscum contagiosum infection. Adalimumab was withdrawn, and the patient started taking supplements, while adopting an anti-inflammatory diet (dairy-free, gluten-free, and sugar-free). Normalization of inflammatory markers was achieved after two months, and magnetic resonance imaging of the sacroiliac revealed a notable physical improvement.

'All disease begins in the gut'-the role of the intestinal microbiome in ankylosing spondylitis

Ankylosing spondylitis is a chronic, debilitating arthritis with a predilection for the axial skeleton. It has a strong genetic predisposition, but the precise pathogenetic mechanisms involved in its development have not yet been fully elucidated. This has implications both for early diagnosis and for effective management. Recently, alterations in the intestinal microbiome have been implicated in disease pathogenesis. In this review, we summarize studies assessing the intestinal microbiome in AS pathogenesis, in addition to synthesizing the literature exploring the postulated mechanisms by which it exerts it pathogenic potential. Finally, we review studies analysing manipulation of the microbiome as a potential therapeutic avenue in AS management.

Characteristics of the intestinal microbiome in ankylosing spondylitis

The importance of intestinal microbiota in the development of various systemic diseases has been highlighted over time. Ankylosing spondylitis (AS) is a systemic disease with a complex pathogenesis involving a particular genetic marker and distinctive environmental triggers such as a specific gut dysbiosis. We conducted a prospective case-control study which included 60 subjects from Iasi Rehabilitation Hospital: 28 AS cases and 32 healthy controls. Intestinal microbiota analysis was performed by real-time polymerase chain reaction (qPCR) in stool samples. We performed the quantitative analysis of gut microbiome, focusing both on anti-inflammatory (Bifidobacterium, Lactobacillus, Faecalibacterium prausnitzii) and pro-inflammatory (Bacteroides, Escherichia coli) species. Overall, intestinal bacterial diversity in the AS group was decreased compared to that noted in the control. A significantly decreased level of Clostridium leptum was observed, associated with an increased level of Escherichia coli. We showed correlations between laboratory tests (liver and kidney functional tests, inflammatory syndrome), the presence of HLA-B27, smoker status, the forms of AS with peripheral arthritis vs. pure axial forms and bacterial structures. No significant correlations were shown for disease activity scores, radiological stage of sacroiliitis or for body mass index. Our findings support that the intestinal microbiome in AS patients has a special signature characterized by an inflammatory status. Numerous environmental, genetical, clinical and paraclinical factors can lead to changes in gut bacterial diversity in these cases.

Non-celiac gluten sensitivity and chronic refractory low back pain with spondyloarthritis features

OBJECTIVE

To propose the hypothesis that non-celiac gluten sensitivity is associated with chronic low-back pain related to spondyloarthritis, and a gluten free diet has a therapeutic benefit in a subgroup of patients. Gut involvement is a well-known association of spondyloarthritis but limited to a few disorders such as inflammatory bowel disease. Currently the therapeutic implication of this association is pharmacologic treatment for inflammation with immunosupresive drugs for both diseases. Here is a case series of patients with chronic low-back pain, spondyloarthritis related features, and response to gluten free diet despite celiac disease being ruled out.

METHODS

Retrospective case report of 110 patients from a tertiary hospital rheumatology clinic specialized in chronic pain and gluten sensitivity. These are patients with refractory low-back pain and spondyloarthritis features who followed a gluten free diet despite celiac disease being ruled out. Demanding improvement was defined based on the achievement of at least one of the following objectives: asymptomatic status, remission of chronic low-back pain, returning to normal life, returning to work, changing from confinement to bed/wheelchair to being able to walk, returning to self-sufficiency for hygiene and personal care, discontinuation of opioids.

RESULTS

Average age at low-back onset pain was 30. Average disease duration was 15 years. 87 (79%) of the patients experienced improvement. 69 (62%) of the patients achieved demanding improvement. Average duration of gluten-free diet in patients with demanding improvement was 60 months. 56 out of 69 patients with demanding improvement ingested gluten. Of these 56 patients, 54 experienced clinical worsening and were considered as having non-celiac gluten sensitivity. Oral aphthae and having a relative with celiac disease were associated with demanding improvement. Out of 28 patients retrospectively classified as having axial spondyloarthritis, 23 had demanding improvement. Out of 16 patients with uveitis, 13 had demanding improvement. Out of 83 patients with fibromyalgia, 48 had demanding improvement.

CONCLUSION

These observational data support the proposed hypothesis and offer information regarding possible clinical predictors of response to diet.

A cross talk between dysbiosis and gut-associated immune system governs the development of inflammatory arthropathies

BACKGROUND

Emerging evidence suggests that dysbiosis, imbalanced gut microbial community, might be a key player in the development of various diseases, including inflammatory arthropathies, such as rheumatoid arthritis, spondyloarthritis (mainly, ankylosing spondylitis and psoriatic arthritis), and osteoarthritis. Yet, the underlying mechanisms and corresponding interactions remain poorly understood.

METHODS

We conducted a critical and extensive literature review to explore the association between dysbiosis and the development of inflammatory arthropathies. We also reviewed the literature to assess the perspectives that ameliorate inflammatory arthropathies by manipulating the microbiota with probiotics, prebiotics or fecal microbiota transplantation.

RESULTS

Some bacterial species (e.g. Prevotella, Citrobacter rodentium, Collinsella aerofaciens, Segmented filamentous bacteria) participate in the creation of the pro-inflammatory immune status, presumably via epitope mimicry, modification of self-antigens, enhanced cell apoptosis mechanisms, and destruction of tight junction proteins and intestinal barrier integrity, all leading to the development and maintainance of inflammatory arthropathies. Whether dysbiosis is an epiphenomenon or is an active driver of these disorders remains unclear, yet, recent observations clearly suggest that dysbiosis precedes and triggers their development implying a causative relationship between dysbiosis and inflammatory arthropathies. The underlying mechanisms include dysbiosis-mediated changes in the functional activity of the intestinal immune cell subsets, such as innate lymphoid cells, mucosa-associated invariant T cells, invariant natural killer T cells, T-follicular helper and T-regulatory cells. In turn, disturbed functionality of the gut-associated immune system is shown to promote the overgrowth of many bacteria, thus establishing a detrimental vicious circle of actively maintaining arthritis.

CONCLUSIONS

Analysis of the data described in the review supports the notion that a close, dynamic and tightly regulated cross talk between dysbiosis and the gut-associated immune system governs the development of inflammatory arthropathies.

The correlation between intestinal dysbiosis and the development of ankylosing spondylitis

The pathogenesis and development of ankylosing spondylitis (AS) is concealed and complicated. In recent years, alterations in gut microbiota of AS patients have been largely investigated, although the underlying mechanisms remain unclear. This article reviews the recent studies on changes of gut microbiota in AS patients, and discusses the possible correlation between intestinal dysbiosis and AS development from aspects including genetic factor HLA-B27, mucosal immune responses and the depression accompanying AS.

Evaluation in terms of dietary habits of rheumatic process: A clinical study

OBJECTIVE

This study compared the dietary habits of patients with ankylosing spondylitis (AS) and rheumatoid arthritis (RA).

METHODS

The nutritional status of 56 patients, seen at the Rheumatology Outpatient Clinic and diagnosed with RA based on the ACR-2010 criteria, was compared with that of 28 patients diagnosed with AS using the modified New York criteria. Nutritional status was determined using a form that was filled out during face-to-face interviews with all patients. Patient demographics, disease activity, smoking and alcohol use, concomitant diseases, disease duration and nutritional status were determined using a questionnaire.

RESULTS

RA patients consumed butter on 2 days a week, and AS patients on 1 day per month. Yoghurt was consumed by RA patients daily and by AS patients 3 days a week.

CONCLUSIONS

Compared to the diet of AS patients, the diet of RA patients was richer in protein and lipids. The impact of diet on these two diseases remains to be determined in large-scale studies.

Relationship between diet and ankylosing spondylitis: A systematic review

The question of whether diet plays a role in the onset of ankylosing spondylitis (AS) or can affect the course of the disease is an important one for many patients and healthcare providers. The aims of this study were to investigate whether: 1) patients with AS report different diets to those without AS; 2) amongst patients with AS, diet is related to severity; 3) persons with particular diets are less likely to develop AS; 4) specific dietary interventions improve the AS symptoms. The review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Medline, Embase, Cochrane Library, and reference lists of relevant articles were searched. Two authors independently selected eligible studies, assessed the quality of included trials, and extracted the data. Sixteen studies (nine observational and seven interventions) were included in the review. Due to the heterogeneity of the study designs and analyses, the results could not be aggregated. Evidence on a possible relationship between AS and diet is extremely limited and inconclusive due to the majority of included studies being small, single studies with moderate-to-high risk of bias, and insufficient reporting of results.

A Possible Role of Intestinal Microbiota in the Pathogenesis of Ankylosing Spondylitis

Ankylosing spondylitis (AS) is a chronic inflammatory disease primarily affecting the sacroiliac joints and the spine, for which the pathogenesis is thought to be a result of the combination of host genetic factors and environmental triggers. However, the precise factors that determine one’s susceptibility to AS remain to be unraveled. With 100 trillion bacteria residing in the mammalian gut having established a symbiotic relation with their host influencing many aspects of host metabolism, physiology, and immunity, a growing body of evidence suggests that intestinal microbiota may play an important role in AS. Several mechanisms have been suggested to explain the potential role of the microbiome in the etiology of AS, such as alterations of intestinal permeability, stimulation of immune responses, and molecular mimicry. In this review, the existing evidence for the involvement of the microbiome in AS pathogenesis was discussed and the potential of intestinal microbiome-targeting strategies in the prevention and treatment of AS was evaluated.

Gut inflammation and microbiome in spondyloarthritis

Spondyloarthritis (SpA) is chronic inflammatory disease involving joints and the spine. Bowel inflammation is common in SpA, which may be classified as acute or chronic. Chronic gut inflammation is most common in SpA patients with axial involvement as compared to those presenting with peripheral involvement alone. The pathogenesis of gut inflammation in SpA could be explained by two factors-over-activation of immunological cells and altered gut microbiome. This is exemplified by SpA animal models, namely HLA-B27-expressing transgenic animals and SKG mice models. Immunological mechanisms include homing of activated T cells from gut into synovium, excess pro-inflammatory cytokines secretion by immune cells such as IL-23 and genetic variations in immunological genes. The evidence for role of gut microbiome in SpA is gradually emerging. Recently, metagenomic study of gut microbiome by sequencing of microbial nucleic acids has enabled identification of new microbial taxa and their functions in gut of patients with SpA. In SpA, the gut microbiome could emerge as diagnostic and prognostic marker of disease. Modulation of gut microbiome is slated to have therapeutic potential as well.

Raised incidence of ankylosing spondylitis among Inuit populations could be due to high HLA-B27 association and starch consumption

Ankylosing spondylitis (AS) is a chronic inflammatory arthritis mainly affecting the spinal joints. It would appear that the most likely causative agent in the development of AS is an environmental factor in the genetically susceptible, HLA-B27 positive, individuals. Extensive data from several countries support the notion that Klebsiella pneumonia bacteria are the most likely culprit in the causation of AS. These microbes possess antigens which resemble HLA-B27 and spinal collagens. Increased intake of high-starch diet is directly proportional to the gut-associated bacterial load, especially in the large intestine, and among these microbial agents, Klebsiella is considered as one of the main constituting components. Therefore, a low-starch diet intake alongside the currently used medical therapeutic modalities could be beneficial in the management of patients with early AS. It is suggested that a change in the dietary habits from high protein, low-starch marine components to the Westernized high-starch diet among the Inuit peoples of Alaska and Canada could be considered as one of the main contributing factors in the increased prevalence of AS during the last few decades within this genetically unmixed native population.

The role of Klebsiella in Crohn's disease with a potential for the use of antimicrobial measures

There is a general consensus that Crohn's disease (CD) develops as the result of immune-mediated tissue damage triggered by infections with intestinal microbial agents. Based on the results of existing microbiological, molecular, and immunological studies, Klebsiella microbe seems to have a key role in the initiation and perpetuation of the pathological damage involving the gut and joint tissues in patients with CD. Six different gastroenterology centres in the UK have reported elevated levels of antibodies to Klebsiella in CD patients. There is a relationship between high intake of starch-containing diet, enhanced growth of gut microbes, and the production of pullulanases by Klebsiella. It is proposed that eradication of these microbes by the use of antibiotics and low starch diet, in addition to the currently used treatment, could help in alleviating or halting the disease process in CD.

The link between ankylosing spondylitis, Crohn's disease, Klebsiella, and starch consumption

Both ankylosing spondylitis (AS) and Crohn's disease (CD) are chronic and potentially disabling interrelated conditions, which have been included under the group of spondyloarthropathies. The results of a large number of studies support the idea that an enteropathic pathogen, Klebsiella pneumoniae, is the most likely triggering factor involved in the initiation and development of these diseases. Increased starch consumptions by genetically susceptible individuals such as those possessing HLA-B27 allelotypes could trigger the disease in both AS and CD by enhancing the growth and perpetuation of the Klebsiella microbes in the bowel. Exposure to increased levels of these microbes will lead to the production of elevated levels of anti-Klebsiella antibodies as well as autoantibodies against cross-reactive self-antigens with resultant pathological lesions in the bowel and joints. Hence, a decrease of starch-containing products in the daily dietary intake could have a beneficial therapeutic effect on the disease especially when used in conjunction with the currently available medical therapies in the treatment of patients with AS and CD.

B27 disease is a new autoimmune disease that affects millions of people

"B27 disease" is a new autoimmune disease that afflicts millions of people throughout the world. "B27 disease" occurs in individuals who have ankylosing spondylitis (AS) or preankylosing spondylitis and/or uveitis and are also positive for HLA-B27. Molecular mimicry between the bowel microbe Klebsiella and the HLA-B27 molecule, as well as the spinal collagens types I, III, and IV, indicates a pathological mechanism involving autoimmunity. Antibodies to Klebsiella microbes have been reported in AS patients from 18 different countries. Sera from patients with AS show complement-dependent cytopathic activity against sheep red cells coated with HLA-B27 peptide antigens. Diagnosis of B27 disease can lead to early treatment, involving low-starch diet, sulfasalazine, and immunosuppressive and biological agents so as to prevent the irreversible bony changes of established classical AS. The concept of B27 disease provides a new approach to the study and treatment of these disorders and needs to be evaluated in prospective studies by the world rheumatological community.

A possible link between Crohn's disease and ankylosing spondylitis via Klebsiella infections

Crohn's disease (CD) is an immune-mediated gastrointestinal inflammatory disease, which could arise from an interplay between genetic and environmental factors. Klebsiella microbes were suggested to have a vital role in the initiation and perpetuation of the disease through the mechanism of molecular mimicry. This proposition is based on the results of various studies where significantly elevated levels of antibodies against the whole bacteria or preparations from Klebsiella microbes and antibodies to collagen types I, III, IV, and V were detected in patients with CD and patients with ankylosing spondylitis (AS). Molecular similarities were found between Klebsiella nitrogenase and HLA-B27 genetic markers and between Klebsiella pullulanase and collagen fibers types I, III, and IV. Furthermore, significantly positive correlations and cross-reactivity binding activities were observed between anti-Klebsiella and anticollagen antibodies among patients with CD and AS. Early treatment of CD patients with anti-Klebsiella measures is proposed, which may involve the use of antibiotics and low starch diet together with other traditionally used immunomodulatory, immunosuppressive, or biologic agents.

Current evidence for the management of ankylosing spondylitis: a systematic literature review for the ASAS/EULAR management recommendations in ankylosing spondylitis

OBJECTIVE

To assess available management strategies in ankylosing spondylitis (AS) using a systematic approach, as a part of the development of evidence based recommendations for the management of AS.

METHODS

A systematic search of Medline, Embase, CINAHL, PEDro, and the Cochrane Library was performed to identify relevant interventions for the management of AS. Evidence for each intervention was categorised by study type, and outcome data for efficacy, adverse effects, and cost effectiveness were abstracted. The effect size, rate ratio, number needed to treat, and incremental cost effectiveness ratio were calculated for each intervention where possible. Results from randomised controlled trials were pooled where appropriate.

RESULTS

Both pharmacological and non-pharmacological interventions considered to be of interest to clinicians involved in the management of AS were identified. Good evidence (level Ib) exists supporting the use of non-steroidal anti-inflammatory drugs (NSAIDs) and coxibs for symptomatic treatment. Non-pharmacological treatments are also supported for maintaining function in AS. The use of conventional antirheumatoid arthritis drugs is not well supported by high level research evidence. Tumour necrosis factor inhibitors (infliximab and etanercept) have level Ib evidence supporting large treatment effects for spinal pain and function in AS over at least 6 months. Level IV evidence supports surgical interventions in specific patients.

CONCLUSION

This extensive literature review forms the evidence base considered in the development of the new ASAS/EULAR recommendations for the management of AS.

Correlation between the immune responses to collagens type I, III, IV and V and Klebsiella pneumoniae in patients with Crohn's disease and ankylosing spondylitis

BACKGROUND

Increased levels of collagen types I, III and V are found in strictures of patients with Crohn's disease (CD) compared with normal gut tissue. Type IV collagen is present in the basement membranes, basal lamina, retina and cornea. Elevated levels of antibody to Klebsiella pneumoniae are found in both active CD and active ankylosing spondylitis (AS) patients compared with healthy controls.

METHODS

Reactivities for immunoglobulin class-specific antibodies (IgM, IgG and IgA) against collagen types I, III, IV, V and whole K. pneumoniae were measured by ELISA in nine patients with early CD and 10 with late CD from King's College Hospital and 12 late CD patients and 36 HLA-B27-positive AS patients from Middlesex Hospital and was compared with values for 26 healthy controls from the Blood Transfusion Service in London.

RESULTS

Levels of class-specific IgM, IgG and IgA antibodies to collagen types I, III, IV, V and K. pneumoniae were significantly elevated in early and late CD patients compared with healthy controls (P<0.001). Levels of IgM, IgG antibody to the four collagen types and K. pneumoniae were also significantly elevated (P<0.001) in AS patients compared with healthy controls. In addition, the level of IgA antibody to K. pneumoniae was elevated in AS patients (P<0.001). Furthermore, a positive correlation between antibody levels to collagen types I, III, IV and K. pneumoniae was demonstrated in both early and late CD patients and in those with AS, whilst a positive correlation to type V was found in early CD.

CONCLUSION

The role of K. pneumoniae and anti-collagen antibodies in the aetiopathogenesis of CD and AS requires further study.