C-reactive protein, ESR, and klebsiella in ankylosing spondylitis

IgA-coated E. coli enriched in Crohn's disease spondyloarthritis promote TH17-dependent inflammation

Peripheral spondyloarthritis (SpA) is a common extraintestinal manifestation in patients with active inflammatory bowel disease (IBD) characterized by inflammatory enthesitis, dactylitis, or synovitis of nonaxial joints. However, a mechanistic understanding of the link between intestinal inflammation and SpA has yet to emerge. We evaluated and functionally characterized the fecal microbiome of IBD patients with or without peripheral SpA. Coupling the sorting of immunoglobulin A (IgA)-coated microbiota with 16S ribosomal RNA-based analysis (IgA-seq) revealed a selective enrichment in IgA-coated Escherichia coli in patients with Crohn's disease-associated SpA (CD-SpA) compared to CD alone. E. coli isolates from CD-SpA-derived IgA-coated bacteria were similar in genotype and phenotype to an adherent-invasive E. coli (AIEC) pathotype. In comparison to non-AIEC E. coli, colonization of germ-free mice with CD-SpA E. coli isolates induced T helper 17 cell (TH17) mucosal immunity, which required the virulence-associated metabolic enzyme propanediol dehydratase (pduC). Modeling the increase in mucosal and systemic TH17 immunity we observed in CD-SpA patients, colonization of interleukin-10-deficient or K/BxN mice with CD-SpA-derived E. coli lead to more severe colitis or inflammatory arthritis, respectively. Collectively, these data reveal the power of IgA-seq to identify immunoreactive resident pathosymbionts that link mucosal and systemic TH17-dependent inflammation and offer microbial and immunophenotype stratification of CD-SpA that may guide medical and biologic therapy.

Investigation of Cardiac Complications and their Incidence in Patients with Ankylosing Spondylitis

INTRODUCTION

Ankylosing Spondylitis (AS) is a chronic inflammatory disease with unknown etiology which involves the sacroiliac and axial joints, but can also cause peripheral conflicts. It also comprises non-joint symptoms such as acute anterior uveitis, cardiac conduction defects, upper lobe pulmonary fibrosis, neurological involvement and renal amyloidosis.

MATERIAL AND METHODS

This study was a cross-sectional descriptive and analytical survey. In this study, 50 patients with AS were examined according to the New York Criteria in Army 501 Hospital in Tehran. Physical examinations, laboratory testing and HLA-B27, as well as X-ray of the spine and sacroiliac joint were taken from all subjects and involvement grading was identified. The control group consisted of 40 healthy people with no evidence of disease. The people resembled the study group in terms of age, sex, smoking, presence of high blood pressure, history of ischemic heart disease and also diabetes.

RESULTS

The mean age of patients in control and study group was 33.97 and 33.65 years, respectively. 37 (92.5%) patients in the control group and 46 in study group (92%) were male. The mean duration of cardiac involvement in patients was 8.6 years with SD=6.26. In AS group, 48 (96%) patients suffered from back pain, 43 from enteritis, 100% from Ankylosing Spondylitis, one from unilateral involvement, 22(44%) from peripheral arthritis and 27 (54%) from HLA-B27.

CONCLUSION

In total, Average heart involvement in the control group and AS group was 13.25 with SD=7.64 and 16.2 with SA=8.54, respectively, indicating no significant difference. In sum, based on the results obtained in this study, some types of heart involvements, such as mitral valve regurgitation and Mitral Valve Prolapse in AS patients are more prevalent than in the normal population.

Ankylosing spondylitis is linked to Klebsiella--the evidence

Ankylosing spondylitis (AS) is a chronic inflammatory spinal and large-joint arthritic and potentially disabling condition, mainly affecting males of young age groups. Extensive literature based on the results of various genetic, microbiological, molecular and immunological studies carried out by independent research groups suggests that Klebsiella pneumoniae is the main microbial agent being implicated as a triggering and/or perpetuating factor in the etiopathogenesis of AS. Novel diagnostic markers and criteria based on the association with high anti-Klebsiella antibodies could be used in the detection of AS patients during early stages of the disease, and together with the current treatments might help in implementing the use of new therapeutic anti-microbial measures in the management of AS. Prospective longitudinal studies with the use of anti-microbial measures in patients with AS are required to establish the therapeutic benefit of this microbe-disease association.

Spondyloarthropathies in childhood

The concept of spondyloarthropathies in childhood is emerging. It should now be more easily recognized since more specific diagnostic criteria are available for young patients. It probably accounts for about 20% of the whole group of chronic arthritides seen in paediatric rheumatology clinics. Juvenile ankylosing spondylitis stricto sensu is very rare in childhood. Most children who present with peripheral arthritis at onset meet the diagnostic criteria of undifferentiated spondylo-arthropathies such as those of the SEA syndrome, or those of the ESSG or Amor criteria. At follow-up, quite a large proportion of children may develop axial involvement. Psoriatic arthritis differs from the other spondyloarthropathies with a different sex ratio, and an earlier onset. The role of immunogenetic, environmental and ethnic factors are important for a better understanding of these diseases.

Bovine spongiform encephalopathy: is it an autoimmune disease due to bacteria showing molecular mimicry with brain antigens?

Bovine spongiform encephalopathy (BSE) could be an autoimmune disease produced following exposure of cattle to feedstuffs containing bacteria showing molecular mimicry between bacterial components and bovine tissue. Analysis of molecular sequence databases (Genbank and SwissProt) shows that three bacteria (Acinetobacter calcoaceticus,Ruminococcus albus, and Agrobacter tumefaciens) share sequences with the encephalitogenic peptide of bovine myelin, while three molecules in Escherichia coli show molecular mimicry with host-encoded prion protein. Immune responses against these bacteria at both T and B cell levels may cause neurological tissue injury resembling BSE. The role of these bacteria in BSE, if any, merits further investigation.

Ig A antibodies to klebsiella in ankylosing spondylitis

In this study anti-klebsiella Ig A values were compared in 40 patients with definite diagnosis of ankylosing spondylitis and a control group of 40 healthy subjects. Anti-Klebsiella Ig A antibody values were significantly higher in patients with ankylosing spondylitis as compared to the control group (p < 0.001). Correlation between these antibodies and erythrocyte sedimentation rate, CRP, serum Ig A, HLA B 27, age, sex and disease duration was searched, but no correlation was found. In our opinion, these results support the suggestion that inflammatory response in ankylosing spondylitis is triggered by Klebsiella but is insufficient to prove the causal relationship between ankylosing spondylitis and Klebsiella.

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

The majority of ankylosing spondylitis (AS) patients not only possess HLA-B27, but during active phases of the disease have elevated levels of total serum IgA, suggesting that a microbe from the bowel flora is acting across the gut mucosa. Biochemical studies have revealed that Klebsiella bacteria, not only possess 2 molecules carrying sequences resembling HLA-B27 but increased quantities of such microbes are found in fecal samples obtained from AS patients and such patients have Crohn's like lesions in the ileo-caecal regions of the gut. Furthermore AS patients from 10 different countries have been found to have elevated levels of specific antibodies against Klebsiella bacteria. It has been suggested that these Klebsiella microbes, found in the bowel flora, might be the trigger factors in this disease and therefore reduction in the size of the bowel flora could be of benefit in the treatment of AS patients. Microbes from the bowel flora depend on dietary starch for their growth and therefore a reduction in starch intake might be beneficial in AS patients. A "low starch diet" involving a reduced intake of "bread, potatoes, cakes and pasta" has been devised and tested in healthy control subjects and AS patients. The "low starch diet" leads to a reduction of total serum IgA in both healthy controls as well as patients, and furthermore to a decrease in inflammation and symptoms in the AS patients. The role of a "low starch diet" in the management of AS requires further evaluation.

Serum IgA anti-Klebsiella antibodies in ankylosing spondylitis patients from Catalonia

IgA antibodies against Klebsiella pneumoniae were measured by immunofluorescence in 84 Catalan patients with ankylosing spondylitis (AS), 41 patients with non-inflammatory arthropathies (NIA) and 22 patients with rheumatoid arthritis (RA). Patients with AS showed higher levels of anti-klebsiella IgA antibodies (IgA-Kp) than NIA and RA patients (4.7 +/- 1.6 U vs 3.7 +/- 1.5 U and 3.1 +/- 1.4 U respectively, p = 0.001). In AS patients a significant correlation between IgA-Kp and levels of C-reactive protein was observed. Although no clear correlation was found between IgA anti-klebsiella and total serum IgA levels, a significant correlation between IgA anti-klebsiella and serum levels of secretory IgA was detected (r: 0.43, p = 0.003). In conclusion, some patients with AS disclosed raised levels of Klebsiella antibodies in sera and this is related to an increase of secretory IgA level. Analysis about the relationship between response to klebsiella and the presence of gut inflammation in AS patients could be of interest.

Comparison of bone scan, computed tomography, and magnetic resonance imaging in the diagnosis of active sacroiliitis

Quantitative bone scan (QBS), computed tomography (CT), and magnetic resonance imaging (MRI) have each been used to confirm the diagnosis of active sacroiliitis (SI) in patients with low back pain (LBP). The authors prospectively evaluated 19 patients referred for symptoms of possible inflammatory LBP (group I), 26 seronegative spondyloarthropathy (SNSP) patients with LBP (group II, inflammatory or mechanical), and 5 SNSP patients without LBP (group III) to determine which radiological scan alone or in combination with other serological tests (Westergren erythrocyte sedimentation rate, C-reactive protein, HLA-B27, immunoglobulin A) was most useful in confirming a clinical diagnosis of active inflammatory SI. All patients were followed up for a minimum of 1 year to confirm the clinical diagnosis and evaluate response to therapy. Eight of 19 group I patients had active SI clinically or on plain radiographs on follow-up evaluation. Of these patients, 5 had abnormal QBS (71%), 3 had abnormal CT scans (38%), and 8 had abnormal MRI scans (100%, type I lesions). These type I MRI lesions were indicative of active inflammation manifested as subcortical bone marrow edema. The remaining 11 group I patients had negative scans for SI. Ten of 26 group II patients with LBP had SI diagnosed clinically and confirmed with positive QBS (60%), CT (100%), and MRI (100%, type I lesions). The remaining 16 group II patients had mechanical LBP without active SI clinically and had negative QBS (88%), CT (19%), and MRI (100%, normal or type II lesions). These type II MRI lesions represented old postinflammatory lesions with either fibrosis or fat replacement. All 5 group III patients had negative scans for active SI. Three patients (2 group I and group II) with inflammatory SI treated with sulfasalazine showed marked improvement on serial MRI scans. Westergren erythrocyte sedimentation rate, C-reactive protein, immunoglobulin A, and CT scan alone or in combination with other tests were not reliable predictors of active SI. Positive QBS and HLA-B27 tests were the best combination of screening tests with 82% predictability of inflammatory SI in whites, and QBS alone had an 80% predictability in black patients. However, MRI, which had 100% predictability, was the best single test for confirming active inflammatory SI.

The value of acute phase protein measurements in clinical practice

There is clearly a role for the measurement of acute phase proteins and other indices of the acute phase reaction but it is equally clear that no one laboratory test is suitable for use in all clinical situations. The choice of acute phase protein measurement depends on the diagnostic sensitivity and specificity of the measurement in the particular clinical situation. The choice of measurement must also include a decision on time of sampling and whether single or serial sampling would be more appropriate. In most situations where acute phase measurement is useful CRP is the assay of choice with alpha 1-antichymotrypsin also being useful in inflammatory bowel disease and other situations where a wider time window is required. The ESR or plasma viscosity can be useful to screen for disease. Cytokine and enzyme-inhibitor complex measurements may be important assays in the future.

IgA antibody response to klebsiella in ankylosing spondylitis measured by immunoblotting

IgA antibodies to Klebsiella pneumoniae var oxytoca and Proteus mirabilis were measured in 66 patients with ankylosing spondylitis (AS) and 31 with rheumatoid arthritis (RA) and in 51 healthy control subjects, using an immunoblotting technique. The number of antigenic bands to klebsiella on nitrocellulose membrane was higher in 28 patients with active AS than in 38 patients with inactive AS, 31 patients with RA, and 51 healthy control subjects; comparatively smaller increases were found against proteus. In two patients with AS the synovial fluid and the corresponding serum sample showed an identical antibody pattern. Increases in IgA antibodies to klebsiella in patients with AS confirm previous studies using other techniques.

HLA and disease

Many human diseases are associated with HLA class I, class II and class III antigens. It appears that the class III antigen disease associations can be explained by a direct defect operating at the level of either the class III gene or its gene product. The mechanism underlying class I and class II antigen disease associations is at present unknown. In this review we have considered thirty diseases which have been ranked according to their relative risk as defined by the frequency of a given HLA antigen in patient and control populations. The chronic inflammatory disorder, ankylosing spondylitis and its association with HLA B27 has been used as a model to study the HLA linked diseases. We have suggested that the disease may be caused by the Gram-negative microorganism Klebsiella which has antigenic similarity to HLA B27. It is proposed that some antibodies made against Klebsiella bind to HLA B27, thereby acting as autoantibodies leading to the pathological sequelae of chronic inflammatory arthritis. This is the crosstolerance hypothesis or molecular mimicry model and it has been compared to the receptor model. It is further suggested that the crosstolerance hypothesis can be utilised as a general theory to explain the association of other diseases with the class I and class II antigens, and offer a possible explanation for the polymorphism of HLA.

Immune complexes in ankylosing spondylitis

Immune complexes have been reported in ankylosing spondylitis (AS) and may implicate infectious agents. Serum samples from 49 patients with AS were assayed for immune complexes by polyethylene glycol precipitation, followed by radial immunodiffusion and pepsinogen binding immunoassay. Both methods showed increases in IgA containing immune complexes, which correlated with serum IgA and with IgA rheumatoid factor concentrations, but did not show increases in other immune complex components. Increased immune complexes were associated with peripheral joint synovitis, but showed no correlation with other clinical or laboratory indices of disease activity. Immune complexes from nine AS serum samples and one AS synovial fluid were electrophoretically separated then probed with anti-Klebsiella pneumoniae, but AS specific antigens were not identified. This study did not suggest a major role for immune complexes in AS without peripheral disease, nor provide serological evidence for the involvement of klebsiella antigens.

C-reactive protein: a critical review

We have reviewed the literature to determine the value of C-reactive protein (CRP) measurements in the diagnosis and management of a wide range of conditions. CRP levels are of value in 6 clinical situations: (a) monitoring the response to antibiotic treatment in patients with known bacterial infections, (b) in obstetric patients with premature rupture of membranes, a rise in CRP can give early warning of intrauterine infections, (c) differentiation between active disease and infections in patients with systemic lupus and ulcerative colitis where the level of response to active disease has been previously established, (d) as a measure of disease activity and response to disease-modifying drugs in rheumatoid arthritis, (e) early detection of complications in postoperative patients, (f) in differentiating between infection and graft-versus-host-disease in bone marrow transplant patients. CRP levels have been used in an attempt to differentiate between bacterial and viral infections in various clinical situations, however the published literature does not support this role.

Sulphasalazine in ankylosing spondylitis. A radiological, clinical and laboratory assessment

In a 12-month double-blind placebo-controlled trial, the effect of sulphasalazine was studied in 40 patients with ankylosing spondylitis. The treatment group showed significant improvement in pain, stiffness, sleep disturbance (p less than 0.05), finger/floor distance, erythrocyte sedimentation rate, C-reactive protein, orosomucoid and IgA levels (p less than 0.01). There was improvement in sleep disturbance (p less than 0.05), finger/floor distance and erythrocyte sedimentation rate (p less than 0.01) in the placebo group. Sulphasalazine did not retard radiological progression as measured either by plain X-ray or computerised tomographic scans. Multiple analysis of variance did not show a significant difference in disease activity indicators between the 2 groups.

Differences in HLA-B27 positive and negative patients with ankylosing spondylitis: study of clinical disease activity and concentrations of serum IgA, C reactive protein, and haptoglobin

To find out whether disease activity and B27 status were associated with serum concentrations of IgA, C reactive protein (CRP), and haptoglobin in ankylosing spondylitis (AS) multivariate analysis of variance was used to study 101 patients with AS whose disease was clinically classified as active or inactive, and who were HLA-B27 typed. It was found that B27 and disease activity do interact significantly to affect the serum concentrations of IgA, CRP, and haptoglobin. When the 77 B27+ patients were examined, however, it was found that disease activity was significantly associated with serum concentrations IgA. In contrast, in the 24 B27- patients concentrations of serum IgA were significantly associated with disease activity, but not. These results emphasise the known difference between B27+ and B27- AS and suggest different pathogenic mechanisms in the two forms of AS.

Serum levels of secretory IgA in ankylosing spondylitis

An ELISA test was performed in order to measure the serum levels of secretory IgA (sIgA) in 51 patients with ankylosing spondylitis (AS) and 30 healthy controls. Raised values of sIgA were found in AS patients compared to controls. Patients with active disease, defined by clinical criteria, showed a significant elevation of serum sIgA compared to healthy controls (p = 0.03) or to patients with inactive disease (p = 0.02). A positive correlation between total serum IgA and sIgA was found (p = 0.001). Our findings further support the role of the mucosal stimulation in the pathogenesis of AS.

The use of enzyme immunoassay (EIA) and radiobinding assay to investigate the cross-reactivity of Klebsiella antigens and HLA B27 in ankylosing spondylitis patients and healthy controls

The binding of rabbit anti-Klebsiella antibodies to tissue-typed lymphocytes obtained from 30 ankylosing spondylitis (AS) patients and 54 healthy subjects has been measured by an enzyme immunoassay method. HLA B27 positive lymphocytes obtained from either AS patients (t = 3.60; p less than 0.001) or healthy subjects (t = 3.77; p less than 0.001) were found to bind Klebsiella antibodies to a significantly greater extent than non-B27 lymphocytes obtained from healthy controls. Absorption studies demonstrated that HLA B27 positive lymphocytes absorbed out significantly more anti-Klebsiella antibodies than HLA B27-negative lymphocytes (t = 6.76; p less than 0.005). These results are compatible with cross-reactivity or molecular mimicry between HLA B27 and epitopes on some Gram-negative bacteria such as Klebsiella.

The relationship between Klebsiella infection and ankylosing spondylitis

Ankylosing spondylitis (AS) is probably produced by repeated episodes of Klebsiella-reactive arthritis, usually in HLA-B27-positive individuals. This concept is based on immunological, microbiological and serological considerations. Immunological studies based on anti-B27 tissue typing sera and anti-B27 monoclonal antibodies indicate that HLA-B27 cross-reacts with antigens found in Klebsiella, Salmonella, Shigella and Yersinia micro-organisms. Salmonella, Shigella and Yersinia gut infections are associated with a reactive arthritis that occurs predominantly in HLA-B27-positive individuals. However, microbiological studies indicate that only Klebsiella, but not Salmonella, Shigella or Yersinia, can be isolated in faecal cultures obtained from AS patients. Furthermore, serological studies involving a number of different techniques demonstrate that only antibodies against Klebsiella, but not against Salmonella, Shigella or Yersinia, can be identified in active AS patients. The evidence is sufficiently extensive to warrant long-term studies involving Klebsiella reduction in the bowel flora of AS patients, in an attempt to reduce the severity and modify the development of the disease. It would appear that Klebsiella-reactive arthritis is the precursor stage occurring in the early and active phases of AS. Only future studies can determine whether this disease will remain a taxonomic curiosity or provide guidelines for therapeutic sequelae which will be of benefit to AS patients.

Raised titres of anti-klebsiella IgA in ankylosing spondylitis, rheumatoid arthritis, and inflammatory bowel disease

Serum titres of IgA are raised in ankylosing spondylitis and increased titres of antibodies to klebsiella have also been reported. The humoral response was investigated in ankylosing spondylitis and other inflammatory disorders. IgA antibodies to klebsiella pneumoniae K43 were measured in patients with ankylosing spondylitis, Crohn's disease, ulcerative colitis, and rheumatoid arthritis and in controls. Significantly raised median titres of anti-klebsiella IgA, measured as optical density at 405 nm with an enzyme linked immunosorbent assay (ELISA), were seen among the patients with ankylosing spondylitis (0.7), Crohn's disease (0.8), rheumatoid arthritis (0.6), and ulcerative colitis (0.8) compared with controls (0.4). Activity of disease in ankylosing spondylitis and titres of anti-klebsiella IgA were not correlated. In contrast, titres of anti-klebsiella IgM were significantly lower in patients with ankylosing spondylitis and ulcerative colitis. The increase in the titres of anti-klebsiella IgA may be due to increased permeability of the gut to bacterial antigens, leading to an increased IgA response in the gut mucosa and permitting the release of IgA into the circulation. As the increased antibody titres were seen in Crohn's disease and rheumatoid arthritis as well as in ankylosing spondylitis the response may be nonspecific, occurring because of possible underlying inflammatory bowel disease in these conditions.

Correlation of immunoglobulin and C reactive protein levels in ankylosing spondylitis and rheumatoid arthritis

Serum C reactive protein (CRP), IgG, and IgA levels were measured in 22 patients with ankylosing spondylitis (AS) and in 20 patients with rheumatoid arthritis (RA) to study the regulation of these proteins in inflammatory disease states. In both RA and AS the mean CRP, IgG, and IgA levels were raised above normal values. Although IgA and CRP levels showed a significant positive correlation in RA (r = 0.53, p = 0.02), there was no correlation between these values in AS (r = 0.24, p = 0.29). The difference in correlation coefficients between the AS and RA groups was significant at a p = 0.05 level. In RA the raised IgA levels may be another manifestation of the acute phase response, as shown by the good correlation between IgA and CRP in that disease. In AS, however, the IgA levels, although raised, do not correlate with CRP levels, suggesting that the mechanism of increase of IgA in the two diseases is different. Gut mediated immune stimulation has been proposed as a cause of raised IgA levels in AS.

C-reactive protein in the assessment of disease activity in juvenile rheumatoid arthritis and juvenile spondyloarthritis

Disease activity in 31 children with JRA and 12 with JSA was investigated clinically and by serial measurements of serum CRP and ESR over a one-year period. Prior mean duration of disease was 4.3 years. There was a significant correlation of CRP with ESR and both parameters correlated significantly with clinical disease activity. CRP concentrations and ESR in active disease were significantly higher than in moderately active and inactive disease, though neither parameter showed any significant difference between moderately active and inactive disease. Clinical scoring was more sensitive in detection of moderate disease activity than were CRP and ESR. However, in systemic JRA without articular involvement, laboratory parameters were more useful for assessing disease activity.

Absence of IgA nephropathy in patients with ankylosing spondylitis

In 40 patients with ankylosing spondylitis (AS) no evidence for IgA nephropathy was obtained. This conclusion was based on the absence of hematuria and on the inability to find an increased incidence of IgA-containing immunoglobulin deposits in skin biopsies. Increased Clq binding assay was only found in those AS patients with anterior uveitis. In 26% of the skin biopsies perivascular mononuclear cell infiltrates were observed, and immunoglobulin deposits were seen in 65%. These facts suggest that the immunologic system is involved in the pathogenesis of this disease.

IgA serum levels and disease activity in ankylosing spondylitis: a prospective study

We investigated the possible association between serum IgA, IgM, and IgG and disease activity in a longitudinal study of 48 weeks' duration in 38 male patients with active ankylosing spondylitis receiving regular treatment with either phenylbutazone or diflunisal. Throughout the study serum IgA levels correlated most frequently with chest expansion and lumbar flexion index, and patients with extensive radiological changes also had the highest serum IgA levels. Likewise, changes in IgA, but not in IgM and IgG, correlated with changes in a composite index of disease activity (IDA). Changes in erythrocyte sedimentation rate (ESR) showed a similar correlation with changes in IDA, whereas changes in serum IgA and ESR showed no consistent correlation, suggesting that both parameters reflect different aspects of disease. Serum IgA, ESR, and IDA values all decreased during regular drug treatment, suggesting a disease modifying effect of the non-steroidal anti-inflammatory drugs (NSAIDs) studied. Regular measurement of serum IgA may be useful in the assessment of disease activity of ankylosing spondylitis.

Spondyloarthritis, uveitis, HLA-B27 and Klebsiella

The association between HLA-B27 and ankylosing spondylitis could be explained by a "crosstolerance hypothesis". Experimental studies demonstrate immunological crossreactivity between HLA-B27 and antigens found in Gram-negative bacteria, such as Klebsiella. Clinical studies show that an increased frequency of patients with ankylosing spondylitis and uveitis have Klebsiella in their fecal cultures. Furthermore, antibodies to Klebsiella can be detected in such patients during active phases of the disease. It is suggested that anti-bacterial antibodies bind to cross-reacting self-antigens, activate the complement cascade and produce inflammation which eventually leads to the development of such chronic diseases as ankylosing spondylitis and uveitis.

Attempt to modify klebsiella carriage in ankylosing spondylitic patients by diet: correlation of klebsiella carriage with disease activity

Patients with ankylosing spondylitis were asked to follow a 'klebsiella exclusion diet' for 5 months of a 10-month study. The same percentage of faecal samples were positive for klebsiella whether the patients were on or off the experimental diet. The diet also failed to influence variability of klebsiella serotypes. We found no correlation between acquisition of klebsiella and deterioration of disease symptoms, as recorded by the patients. Furthermore, carriage of klebsiella did not correlate with any of the following parameters of disease activity measured in the outpatient clinic: morning stiffness, pain measured on a visual analogue scale, analgesic consumption, ESR, total serum IgA. We found no evidence, therefore, that faecal klebsiella is involved in disease exacerbations of ankylosing spondylitis.

A solid-phase enzyme immunoassay for C-reactive protein: clinical value and the effect of rheumatoid factor

Measurement of serum C-reactive protein (CRP) concentration is useful in monitoring the progress of chronic inflammatory diseases. Rheumatoid factor, by its interaction with the Fc portion of IgG, has the potential to interfere with solid-phase immunoassays for CRP and other serum proteins. To determine the effect of RF on a solid-phase enzyme immunoassay for CRP we compared assays employing whole antisera or F(ab')2 fragments. In 92 sera with RF latex titres ranging from 1/80 to 1/81,920, no correlation was found between RF concentrations and CRP measurements. CRP concentrations measured by use of whole antisera (mean +/- standard error of the mean, 59.7 +/- 5.7 mg/l, n = 92) were lower than those measured with F(ab')2 fragments (62.5 +/- 5 mg/l), indicating that exaggeration of CRP measurements did not occur in RF containing sera under the conditions of the assay. Our results show that in the CRP-ELISA, interference from RF was precluded by the high serum dilutions employed. At lower serum dilutions RF binding was detected. Consequently, in solid-phase enzyme immunoassays at lower serum dilutions the presence of RF may lead to false positive results and exaggerated measurements.

HLA-B27 and the immune response to enterobacterial antigens in ankylosing spondylitis

Total serum immunoglobulins and class specific serum antibodies to Klebsiella pneumoniae, Salmonella typhimurium, Yersinia enterocolitica and Pseudomonas aeruginosa were measured in 107 patients with ankylosing spondylitis (AS) and 110 healthy tissue typed controls by enzyme linked immunosorbent assay (ELISA). The specificity of this technique was confirmed by the use of specific bacterial murine antisera and by cross-absorption of human sera by specific bacteria. Total serum IgA in AS patients correlated with both erythrocyte sedimentation rate (ESR) (P less than 0.001) and C-reactive protein (P less than 0.05) and was significantly elevated compared to healthy individuals (P less than 0.001). A significant elevation of IgA antibodies to K. pneumoniae was detected in the serum of AS patients with active disease when compared to healthy controls (P less than 0.01). These studies support the involvement of an enterobacterial micro-organism in the pathogenesis of AS and further relate to the role of HLA-B27 in this disease.

C-reactive protein and serological indices of disease activity in systemic lupus erythematosus

The concentration of C-reactive protein (CRP) in sera from 70 patients with systemic lupus erythematosus (SLE) showed no correlation with commonly accepted laboratory indices of disease activity. Most patients had detectable serum CRP, but in some patients CRP was not found despite repeated testing. This absence of a CRP response did not appear to be related to medication. In some patients high levels of CRP were seen in the absence of infection. Measurement of serum CRP in SLE is unlikely to be useful in the laboratory diagnosis of disease activity.

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

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

Acute-phase proteins and serum immunoglobulins in ankylosing spondylitis

The erythrocyte sedimentation rate (ESR) and the serum acute-phase proteins (APP), C-reactive protein (CRP), fibrinogen, 9th component of complement (C9), and alpha, antitrypsin were measured on 231 occasions in 80 patients with ankylosing spondylitis and compared with those in 30 controls. APP levels did not correlate with clinical assessment of disease activity. However, there were significant correlations between CRP, C9, and fibrinogen (p = less than 0.01), suggesting that these APP may be more reliable indicators of disease activity. The mean values of the APP in those patients with a peripheral arthritis were significantly higher than in those with pelvospondylitis alone for ESR (p less than 0.01), CRP (p less than 0.01), and fibrinogen (p less than 0.05). The only significant difference between those patients with an iritis and those with only pelvospondylitis was an elevated CRP in the iritis group (p less than 0.01). This suggests that a peripheral arthritis is the most important cause of an elevated ESR or APP in ankylosing spondylitis. Serum immunoglobulins were also measured and they showed a significant elevation of IgA in all 3 patients groups, there being no difference between each group. Serum IgG was raised only in those patients with an iritis or peripheral arthritis, the IgM levels being within the normal range for all patient groups.

Hepatic function in ankylosing spondylitis

Values for alkaline phosphatase and gamma glutamyl transpeptidase (GGTP) and the prevalence of their elevation was significantly higher in 35 patients with ankylosing spondylitis (AS) than in 35 age and sex matched controls. The abnormal enzyme levels appeared to reflect a non-specific reaction to inflammation and could thus aid in assessment of disease status.

IgA antibodies to Klebsiella pneumoniae in ankylosing spondylitis

Serum IgA antibodies to Klebsiella pneumoniae were measured in 65 patients with ankylosing spondylitis (AS) during different phases of disease activity and compared with the antibody level in 21 psoriatic arthritis (PsA) patients, 43 rheumatoid arthritis (RA) patients and 57 healthy controls. The mean IgA antibody to Klebsiella in AS patients with an erythrocyte sedimentation rate (ESR) greater than or equal to 15 mm/h was significantly higher than the antibody level in patients with an ESR less than 15 mm/h (p less than 0.02) and tended to increase with rising ESR. There was a significant difference in anti-Klebsiella antibody levels between AS patients with an elevated ESR and antibody levels in PsA patients (p less than 0.001), RA patients (p less than 0.001) and healthy controls (p less than 0.005). There was no difference between healthy controls and patients with PsA, RA or AS patients with a low ESR. The IgA anti-Klebsiella antibody was specifically absorbed out from sera with inactivated klebsiella pneumoniae organisms. Antibody levels to Candida albicans and Escherichia coli did not differ in patients vis-à-vis control subjects. The mean serum anti-Klebsiella IgA level was found to be higher in patients who were either clinically active or had positive faeval cultures, when compared with patients with inactive disease and negative cultures, but these differences were not statistically significant, although when both parameters were examined together a significant additive effect was detected (p less than 0.001). It is concluded that patient with AS exhibit a specific elevation of serum IgA antibody to Klebsiella antigen.

Acute phase proteins with special reference to C-reactive protein and related proteins (pentaxins) and serum amyloid A protein

The acute phase response among plasma proteins is a normal response to tissue injury and is therefore a fundamental aspect of many diverse disease processes. It probably usually has a beneficial net function in limiting damage and promoting repair but in some circumstances it may have pathological consequences. Sustained high levels of acute phase proteins and especially SAA are associated with the development of amyloidosis in some individuals. Increased concentrations of CRP may, by activating the complement system, contribute to inflammation and enhance tissue damage. Failure of the normal or appropriate CRP response may also possibly have deleterious effects. SAA is a polymorphic protein which is normally present only in trace amounts but which, during the acute phase response, becomes one of the major apolipoproteins associated with high-density lipoprotein particles. The function of apoSAA is not known but it must have considerable physiological significance apart from its role as the putative precursor of amyloid A protein fibrils. CRP and SAP have been very stably conserved throughout vertebrate evolution and homologous proteins are apparently present even in vertebrates. This strongly suggests that they have important functions although these have not yet been precisely delineated. The main role of CRP may be to provide for enhanced clearance of inappropriate materials from the plasma whether these are of extrinsic origin, such as microorganisms and their products, or the autologous products of cell damage and death. The interaction between aggregated CRP and plasma low-density lipoprotein may play a significant part in the normal function of CRP and may also have a role in lipoprotein metabolism, clearance, and deposition. SAP is a normal tissue protein as well as being a plasma protein. Aggregated SAP selectively binds fibronectin and this may represent an aspect of the normal function of SAP. The deposition of SAP in amyloid is evidently not a normal function but it is not known whether this deposition is involved in the pathogenesis of amyloid or whether it is merely an epiphenomenon. In any case immunohistochemical staining for SAP is useful in the diagnosis of amyloid, in investigation of glomerulonephritis, and in studying disorders of elastic tissue. Regardless of its physiological or pathophysiological functions, the assay of serum CRP is a valuable aid to clinical management in a number of different situations and in different diseases provided results are interpreted in the light of full clinical information.(ABSTRACT TRUNCATED AT 400 WORDS)

C-reactive protein in juvenile chronic arthritis: an indicator of disease activity and possibly amyloidosis

C-reactive protein (CRP) was found to be particularly high early in the course of those cases of juvenile chronic arthritis (JCA) with a systemic onset, the mean level being 12 mg/dl (120 mg/l). It was also raised in cases with a polyarticular onset, mean level 6 mg/dl, while in cases with a pauciarticular onset it was associated with only a modest increase up to 1.5 mg/dl (15 mg/l). At the onset of disease there was a good correlation with the erythrocyte sedimentation rate (ESR). Regression of systemic disease was associated with a steady fall in C-reactive protein, but those patients who developed amyloidosis within 5 years from onset had persistently high values until cytotoxic therapy was introduced. Patients who developed amyloidosis later tended to have high CRP levels in the months or even years before diagnosis. In a few patients with polyarthritis the CRP appeared to reflect severe disease more closely than their relatively low ESR.

Secretory IgA: immune defence pattern in ankylosing spondylitis and klebsiella

Saliva secretory IgA (sIgA), secretory component (SC); serum immunoglobulins (IgG, IgA, IgM), complement (C3, C4), C-reactive protein (CRP), and erythrocyte sedimentation rate (ESR) were performed in 32 patients with ankylosing spondylitis and 29 normal controls. They were investigated for carriage in the faeces of Klebsiella spp. on 3 occasions over the previous months. Throat swabs and urine were cultured at the same time as immunological estimations were done. 24-hour urine sIgA specimens were studied in 13 patients and 12 normal controls. Significantly raised mean values of saliva sIgA and serum IgG, IgA, C3, and C4 were found in patients with raised values of serum ESR and CRP levels when correlated with controls. Raised values of sIgA in saliva, which is an important factor of the local immune defence mechanism of mucosal surfaces, suggests the presence of an antigenic stimulus from the gastrointestinal system in ankylosing spondylitis during activity of disease.

A comparison of serum biochemistry in ankylosing spondylitis, seronegative and seropositive rheumatoid arthritis

The serum biochemistry of 31 patients with ankylosing spondylitis (AS) was compared with that of 80 patients with rheumatoid arthritis (RA) (ARA criteria), 30 of whom were negative for circulating rheumatoid factor and 50 of whom were 'seropositive'. All patients were selected because of moderate to severe disease activity. All 3 groups had distinctive biochemical profiles. Total serum sulphydryl and haemoglobin were particularly good discriminators between AS and RA, IgG, IgA, and acute-phase reactants complemented the sheep cell agglutination test in discriminating between seropositive RA and seronegative RA. In active AS a normal erythrocyte sedimentation rate was often seen in the presence of abnormal C-reactive protein (CRP) and plasma viscosity.

C-reactive protein fifty years on

The discovery of C-reactive protein (CRP) half a century ago led to the description of the acute-phase reaction which is a fundamental response of the body to injury. Recent work on the structure and function of CRP has revealed the existence of a unique plasma protein family, including CRP and serum amyloid P component (SAP). These proteins have been conserved throughout vertebrate evolution. CRP binds specifically to a wide range of substances derived both from damaged autologous cells and from microorganisms. Complexed CRP can activate the complement system and, by virtue of its dramatically increased production in response to tissue injury, it probably acts primarily as a protective mechanism. However, in some circumstances CRP may also initiate or exacerbate inflammatory lesions. Clinical measurement of serum CRP is valuable as a screening test for organic disease and as a sensitive object index of disease activity and response to therapy in some inflammatory, infective, and ischaemic conditions. SAP closely resembles CRP in structure but not an acute-phase reactant in man. An apparently identical protein, amyloid P component (AP), is always found in amyloid deposits. AP is also found in normal tissues, as an integral constituent of vascular basement membranes and is located on the peripheral microfibrillar mantle of elastic fibres throughout the body.

Association of inflammation with raised serum IgA in ankylosing spondylitis

Serum immunoglobulins were measured in 122 patients with ankylosing spondylitis (AS) during various phases of disease activity and compared to those in 58 healthy subjects. The mean serum IgA was 38% higher in patients (306.9 mg/dl) than in controls (222.7 mg/dl) (P < 0.005), but there was no significant difference in IgG and IgM levels. Increased IgA was associated with laboratory parameters of active inflammatory disease. The mean IgA in patients having an erythrocyte sedimentation rate (ESR) equal to or greater than 15 mm/h was 369 mg/dl, 65% higher than in controls (P < 0.001), whereas there was no significant difference between controls and patients with an ESR of less than 15 mm/h. The mean IgA in patients having a C-reactive protein (CRP) level equal to greater than 15 micrograms/ml (15 mg/l) was 387.8 mg/dl, 74% higher than in controls (P < 0.001), and again there was no significant difference between controls and patients with CRP levels less than 15 micrograms/ml. (SI conversion: g/l = mg/dl x 0.01). It is suggested that selective increase of serum IgA occurs predominantly during phases of active inflammatory disease in AS, and this finding is compatible with the concept of a microbial triggering agent acting across an IgA secreting organ such as the gut.

Increased incidence of faecal Klebsiella pneumoniae in patients with HLA B7 CREG antigen and men with rheumatoid arthritis

In a study of the carriage of faecal Klebsiella pneumoniae in 106 patients with rheumatoid arthritis the incidence of carriage was higher in men (28%) than women (14%) (p < 0.001) and klebsiellae were isolated on two or more occasions from a higher proportion of men than women (p < 0.002). The incidence of carriage was increased among patients with rheumatoid arthritis who had B7 cross-reacting (B7 CREG) antigens (32% v 13%--p < 0.001). Carriage of klebsiellae was not associated with clinical disease activity, raised erythrocyte sedimentation rate, drug treatment, or the presence of HLA Dw4 or DRw4 or both. Thus the carriage and prevalence of faecal Klebsiella pneumoniae appear to be partly determined by the sex and HLA state of the host.