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H Sörensen

Publications and source records attributed to H Sörensen.

At least 19 recordsLinked to original sources

Outcome of patients with active ankylosing spondylitis after two years of therapy with etanercept: clinical and magnetic resonance imaging data.

OBJECTIVE: To examine the long-term outcome of patients with active ankylosing spondylitis (AS) clinically and by magnetic resonance imaging (MRI) after continuous treatment with the tumor necrosis factor (TNF) receptor fusion protein etanercept over 2 years. METHODS: Overall, 26 patients with active AS were treated with etanercept 25 mg twice daily subcutaneously, twice weekly with no concomitant disease-modifying antirheumatic drugs (DMARDs) or steroids. The clinical response was assessed by standardized parameters. Inflammatory spinal lesions were quantified by the ASspiMRI-a rating gadolinium-enhanced (T1-weighted gadolinium diethylenetriaminepentaacetic acid) and STIR MRI sequences. The primary outcome was a Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) improvement > or =50% after 2 years of etanercept therapy compared with the baseline value of the study. RESULTS: Overall, 21 (70%) of 30 patients completed year 2. In the intent-to-treat analysis, 54% of the patients showed a 50% improvement according to the BASDAI and a 40% improvement according to the Assessment in Ankylosing Spondylitis (ASAS) criteria. In the completer analysis, 9 (43%) of 21 patients were in partial remission according to ASAS criteria. Mean +/- SD BASDAI scores, which were elevated at baseline (6.3 +/- 1.6), remained low: 2.7 +/- 2.4 after 2 years compared with 2.6 +/- 2.2 at week 54. In accordance, all other clinical parameters showed sustained improvement during year 2. The majority of patients had no disease activity flares. MRI evaluation showed a 75% improvement of active spinal lesions, but minor spinal inflammation was still present in 64% of the patients after 2 years. There were 2 serious adverse events leading to discontinuation of etanercept. CONCLUSION: The clinical efficacy and safety of etanercept in patients with active AS without simultaneous administration of DMARDs or steroids over 2 years of continuous treatment is confirmed. Spinal inflammation as depicted by MRI decreased significantly, but a few patients still had some spinal inflammation even after long-term anti-TNF therapy.

Adult↗

New onset or exacerbation of psoriatic skin lesions in patients with definite rheumatoid arthritis receiving tumour necrosis factor alpha antagonists.

BACKGROUND: Blockage of tumour necrosis factor alpha (TNFalpha) is highly effective in rheumatic diseases, especially in rheumatoid arthritis (RA), ankylosing spondylitis, and psoriatic arthritis. Furthermore, TNFalpha antagonists have also been shown to significantly reduce psoriatic skin lesions. CASE REPORTS: A series of nine patients with RA who were treated with different types of TNFalpha antagonists and who unexpectedly developed either a new onset or an exacerbation of psoriatic skin lesions are reported.

Adalimumab↗

Persistent clinical response to the anti-TNF-alpha antibody infliximab in patients with ankylosing spondylitis over 3 years.

OBJECTIVE: Infliximab, a monoclonal antibody against tumour necrosis factor alpha (TNF-alpha), is approved in Europe for the treatment of patients with active ankylosing spondylitis (AS) who have responded inadequately to conventional therapy. This report provides analyses from a 3-yr extension study, as a follow-up to both the 1- and 2-yr open label extensions of the original 3-month randomized controlled trial of infliximab in patients with AS. METHODS: Of the 49 patients with AS who completed the second year of the study, 46 continued treatment with infliximab 5 mg/kg every 6 weeks up to week 156. The Bath AS Disease Activity Index (BASDAI), the Bath AS Functional Index, the Bath AS Metrology Index, patient's and physician's global assessments, quality of life (Short Form-36), C-reactive protein (CRP) and erythrocyte sedimentation rate were assessed throughout the study period. RESULTS: The improvement of signs and symptoms observed in the majority of the patients during the first and second year was sustained throughout the third year of the study. Forty-three patients (62% of the 69 patients enrolled at baseline and 93% of the patients who started the third year) completed week 156. In the intention-to-treat analysis, an ASAS '5 out of 6' and ASAS 40% response was seen by 46% and 50% of the patients, respectively. The scores for other efficacy assessments were similar to the values observed at weeks 54 and 102. Median CRP levels remained low (1.5 mg/l at week 156). There were no relevant side-effects and no discontinuation because of drug-related adverse events during the third year of the study. CONCLUSIONS: Patients with AS receiving infliximab for 3 yr showed a durable clinical response without loss of efficacy. Long-term infliximab treatment was well tolerated by patients in this study.

Adult↗

Long-term efficacy and safety of etanercept after readministration in patients with active ankylosing spondylitis.

OBJECTIVES: Treatment of ankylosing spondylitis (AS) with the tumour necrosis factor alpha (TNF-alpha) receptor fusion protein etanercept has shown efficacy in patients with active disease in randomized controlled trials (RCTs) for limited periods. The objective of the study was to assess the long-term efficacy and safety of etanercept over 1 yr, including discontinuation and readministration. METHODS: In this 54-week open observational study, 26 AS patients received 25 mg etanercept subcutaneously twice weekly after several months of discontinuation following a 6-month RCT with the same agent. All patients who developed high disease activity after cessation of etanercept, defined as a Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) > or = 4 and pain > or = 4 on a numerical rating scale, entered the study. Standard assessment tools, such as the Bath Ankylosing Spondylitis functional index (BASFI), were used. An intention-to-treat (ITT) and a completer analysis were performed. The results were compared with the baseline values of the open study. RESULTS: Out of the initial 30 patients, 26 (87%) were eligible for the open extension study after a mean of about 27 weeks. At week 54, 23/26 patients (88%) were still on treatment with etanercept. The ITT analysis showed that 58% (95% confidence interval 39-74%) of the patients achieved a 50% improvement of BASDAI at week 54. According to the Assessments in Ankylosing Spondylitis working group criteria, 8/26 patients (31%) were in partial remission at week 54. Function, metrology and quality of life improved significantly. Only one patient had a serious adverse event that resulted in discontinuation. CONCLUSIONS: This study shows that treatment with etanercept is efficacious and safe after readministration over 1 yr in patients with active AS not taking DMARDs or steroids.

Adult↗

Two year maintenance of efficacy and safety of infliximab in the treatment of ankylosing spondylitis.

OBJECTIVE: To obtain results of the second year extension of an original 3 month randomised, placebo controlled trial (and the 1 year extension study) assessing the use of infliximab, a monoclonal antibody to tumour necrosis factor alpha, for the treatment of patients with ankylosing spondylitis (AS). METHODS: Of the 54 patients with AS who completed the first year of the study, 52 continued to receive infliximab 5 mg/kg every 6 weeks up to week 102. The primary end point was the proportion of patients achieving at least 50% improvement from baseline in the Bath AS Disease Activity Index (BASDAI) at week 102. Other assessments included patient and physician global assessments, quality of life as assessed by Short Form-36, Bath AS Functional Index, Bath AS Metrology Index, and C reactive protein (CRP). RESULTS: Improvement in signs and symptoms of AS seen during the first year of the study was sustained during the second year. Forty nine patients (71% of 69 enrolled patients and 49/52 (94%) patients who started year 2) completed the study up to week 102. Thirty (58%) patients achieved at least 50% improvement from baseline in the BASDAI score at week 102. Scores for other efficacy assessments were similar at weeks 54 and 102. Median CRP levels remained low at weeks 54 and 102 (3.9 and 4.3 mg/l, respectively). Side effects during the second year of the study were similar to those of the first year of treatment with infliximab. CONCLUSIONS: Patients with AS treated for 2 years with infliximab 5 mg/kg exhibited a good and durable clinical response.

Adult↗

The efficacy and safety of leflunomide in patients with active rheumatoid arthritis: a five-year followup study.

OBJECTIVE: To investigate the efficacy and safety of leflunomide beyond 2 years in a multinational, open-label extension of 2 phase III double-blind studies. METHODS: Patients with rheumatoid arthritis (RA) who received leflunomide (100 mg/day for 3 days, 10 mg/day or 20 mg/day thereafter) in the 2 phase III studies and who completed 2 years of treatment were offered inclusion in the open-label extension phase and were maintained on the same dosage of leflunomide. The American College of Rheumatology revised criteria for 20% improvement (ACR20), ACR50, and ACR70 response rates, the Stanford Health Assessment Questionnaire (HAQ) scores, and C-reactive protein (CRP) levels were assessed. Safety measures included monitoring of adverse events and laboratory values. RESULTS: A total of 214 patients (mean age 57 years) were treated with leflunomide for >2 years; 74.8% of the patients were female. The mean disease duration was 4.1 years (range 0.1-26.6 years), and in 44% of patients, RA was first diagnosed within 2 years of entry into the phase III studies. The mean duration of leflunomide treatment was 4.6 years (range 2.8-5.8 years), and 32% of patients had received no previous treatment with disease-modifying antirheumatic drugs. ACR20, ACR50, and ACR70 response rates and HAQ scores at 1 year were maintained through year 4 or until the end point. No new types of adverse events were observed, and liver function was normal at baseline and at the end point in the majority of patients. CONCLUSION: The improvements in both functional ability and physician-based efficacy measures seen with leflunomide after 1 year were maintained for up to 5 years (maximum treatment duration 5.8 years), demonstrating that the early efficacy of leflunomide in patients with RA is sustained long-term, and that the long-term safety profile of leflunomide is no different from that observed in phase III trials.

Anti-Inflammatory Agents, Non-Steroidal↗

Six-month results of a double-blind, placebo-controlled trial of etanercept treatment in patients with active ankylosing spondylitis.

OBJECTIVE: There is increasing evidence that tumor necrosis factor alpha (TNFalpha) is centrally involved in the pathogenesis of ankylosing spondylitis (AS) and other spondylarthritides. This study was designed to investigate the efficacy of anti-TNFalpha therapy with etanercept, a 75-kd receptor fusion protein, in active AS. METHODS: This multicenter trial had 2 phases: an initial placebo-controlled period of 6 weeks' duration and an observational phase lasting 24 weeks. Thirty patients with active AS were included. They were randomized into 2 groups, which received either etanercept (25 mg twice weekly) (n = 14) or placebo (n = 16) for 6 weeks. Then both groups were treated with etanercept. Nonsteroidal antiinflammatory drug (NSAID) treatment could be continued, but disease-modifying antirheumatic drugs (DMARDs) and steroids had to be withdrawn prior to the study. All patients received etanercept for a total of 12 weeks and were followed up for at least 24 weeks. The Bath AS Disease Activity Index (BASDAI), Bath AS Functional Index, Bath AS Metrology Index, pain level on a numeric rating scale, quality of life by the Short Form 36, and C-reactive protein (CRP) level were assessed. The primary outcome parameter was a >or=50% improvement in the BASDAI. RESULTS: Treatment with etanercept resulted in at least a 50% regression of disease activity in 57% of these patients at week 6, versus 6% of the placebo-treated patients (P = 0.004). After the placebo-treated patients switched to etanercept, 56% improved. The mean +/- SD BASDAI improved from 6.5 +/- 1.2 at baseline to 3.5 +/- 1.9 at week 6 in the etanercept group, with no improvement in the placebo group (P = 0.003 between groups). Similarly, pain, function, mobility, and quality of life improved with etanercept but not with placebo at week 6 (P < 0.05). Mean CRP levels decreased significantly with etanercept but not with placebo (P = 0.001). There was ongoing improvement in all parameters in both groups until week 12 and week 18, respectively (i.e., throughout the period of etanercept treatment). Disease relapses occurred a mean +/- SD of 6.2 +/- 3.0 weeks after cessation of etanercept. No severe adverse events, including major infections, were observed during the trial. CONCLUSION: This study shows that on a short-term basis (3 months), treatment with etanercept is clearly efficacious in patients with active AS who are receiving NSAID therapy but not DMARDs or steroids. After cessation of therapy, almost all patients experienced a relapse within a few weeks. Thus, it seems probable that etanercept must be administered continuously in most AS patients to achieve permanent inhibition of the inflammatory process.

Adult↗

Long-term efficacy and safety of infliximab in the treatment of ankylosing spondylitis: an open, observational, extension study of a three-month, randomized, placebo-controlled trial.

OBJECTIVE: Treatment of ankylosing spondylitis (AS) with infliximab, an anti-tumor necrosis factor alpha monoclonal antibody, was shown to be efficacious in patients with active disease during a 3-month treatment period. The purpose of this study was to evaluate the efficacy and safety of infliximab treatment of AS for a 1-year period. METHODS: This study was an open, observational, extension study of a 3-month, randomized, placebo-controlled trial. All patients who had tolerated infliximab (infliximab/infliximab group) or placebo (placebo/infliximab 12-week crossover group) therapy for 3 months entered the open extension trial (n = 65). Infliximab was administered at a dosage of 5 mg/kg every 6 weeks after the induction phase (weeks 0, 2, and 6). The primary end point was a 50% improvement in the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI). RESULTS: At week 54, a total of 54 of the 69 patients (78%) continued to take infliximab. The intent-to-treat primary efficacy analysis at week 54 showed that 47% of patients in the infliximab/infliximab group (95% confidence interval 31-63) and 51% of the patients in the placebo/infliximab group (95% confidence interval 36-67) achieved 50% improvement in BASDAI scores. In the analysis of those who completed the study, the mean BASDAI scores improved between weeks 0 and 54 in both treatment groups: from 6.6 to 2.4 in the infliximab/infliximab group and from 6.3 to 2.6 in the placebo/infliximab group. The dosage of nonsteroidal antiinflammatory drugs was reduced in approximately 70% of the patients. There were significant improvements in measures of functioning, metrologic parameters, and quality of life. Between weeks 12 and 54, a total of 4 patients had serious adverse events that were possibly related to infliximab and resulted in their discontinuing the study. CONCLUSION: Infliximab therapy in AS patients resulted in a rapid and significant improvement in BASDAI scores (>50% improvement) and a durable response for 1 year. The safety profile of infliximab in AS was comparable to that observed in the postmarketing experience for the approved indications.

Acute-Phase Proteins↗

Treatment of active ankylosing spondylitis with infliximab: a randomised controlled multicentre trial.

UNLABELLED: BACKGROUND Treatment options for patients with ankylosing spondylitis are few. We aimed to assess the effectiveness of infliximab, an antibody to tumour necrosis factor (TNF)-alpha, in treatment of such patients. METHODS: In this 12-week placebo-controlled multicentre study, we randomly assigned 35 patients with active ankylosing spondylitis to intravenous infliximab (5 mg/kg) and 35 to placebo at weeks 0, 2, and 6. One patient in the infliximab group was withdrawn from the study. Our primary outcome was regression of disease activity of at least 50%. To assess response, we used validated clinical criteria from the ankylosing spondylitis assessment working group, including disease activity (BASDAI), functional indices (BASFI), metrology (BASMI), and quality of life (short form 36). Analyses were done by intention to treat. FINDINGS: 18 (53%) of 34 patients on infliximab had a regression of disease activity at week 12 of at least 50% compared with three (9%) of 35 on placebo (difference 44% [95% CI 23-61], p<0.0001). Function and quality of life also improved significantly on infliximab but not on placebo (p<0.0001 and p<0.0001, respectively). Treatment with infliximab was generally well tolerated, but three patients had to stop treatment because of systemic tuberculosis, allergic granulomatosis of the lung, or mild leucopenia. INTERPRETATION: Our results show that treatment with infliximab is effective in patients with active ankylosing spondylitis. Since there are some potentially serious adverse effects, we recommend that this treatment mainly be used in co-operation with rheumatological centres.

Adult↗

Atopic disorders in ankylosing spondylitis and rheumatoid arthritis.

BACKGROUND: The prevalence of atopic disorders in ankylosing spondylitis (AS) is unknown. AS and rheumatoid arthritis (RA) exhibit divergent T helper (Th) cell cytokine patterns. OBJECTIVE: To test the hypothesis that Th2 polarised atopic disorders may be decreased in Th1 polarised RA but increased in AS, which is characterised by an impaired Th1 cytokine pattern, by assessing the prevalence of atopic disorders in AS and RA. METHODS: 2008 subjects (380 patients with AS, 728 patients with RA, 900 controls) from Berlin, Germany, were considered in this cross sectional study. A questionnaire incorporating questions from the European Community Respiratory Health Service (ECRHS) and the International Study of Asthma and Allergies in Childhood (ISAAC) protocol was mailed to all subjects. Disease severity was assessed by the modified Health Assessment Questionnaire (mHAQ). RESULTS: 1271 (63.3%) people responded to the questionnaire. The prevalence of any atopic disorder was 24.6% (61/248) in patients with AS, 20.7% (111/536) in controls, and 13.1% (64/487) in patients with RA (p=0.0009 for AS v RA; p=0.001 for controls v RA). Hay fever was reported by 40/248 (16.1%) patients with AS, 82/536 (15.3%) controls, and 42/487 (8.6%) patients with RA (p=0.002 for AS v RA; p=0.001 for controls v RA). Atopic dermatitis was reported by 19/248 (7.7%) patients with AS, 26/536 (4.9%) controls, and 14/487 (2.9%) patients with RA (p=0.003 for AS v RA), and asthma by 18/248 (7.3%) patients with AS, 35/536 (6.5%) controls, and 21/487 (4.3%) patients with RA. The differences were related neither to age nor to drugs. Disease severity was less in atopic patients with RA who had the atopic disorder before the onset of RA (median mHAQ 0.75) than in patients in whom RA preceded the atopic disorder (median mHAQ 1.75; p=0.027). CONCLUSIONS: Atopic disorders are decreased in RA but only slightly and non-significantly increased in AS. This may imply that atopy confers some protection from RA but only little if any susceptibility to AS. It may further indicate that the cytokine deviation towards an impaired Th1 pattern in AS is less strong than the cytokine deviation towards Th1 in RA, a finding which may affect future therapeutic approaches.

Adult↗

The direct thrombin inhibitor melagatran and its oral prodrug H 376/95: intestinal absorption properties, biochemical and pharmacodynamic effects.

UNLABELLED: Suboptimal gastrointestinal absorption is a problem for many direct thrombin inhibitors. The studies presented herein describe the new oral direct thrombin inhibitor H 376/95, a prodrug with two protecting residues added to the direct thrombin inhibitor melagatran. Absorption properties in vitro: H 376/95 is uncharged at intestinal pH while melagatran is charged. H 376/95 is 170 times more lipophilic (octanol water partition coefficient) than melagatran. As a result, the permeability coefficient across cultured epithelial Caco-2 cells is 80 times higher for H 376/95 than for melagtran. Pharmacokinetic studies in healthy volunteers: H 376/95 is converted to melagatran in man. Oral bioavailability, measured as melagatran in plasma, is about 20% after oral administration of H 376/95, which is 2.7-5.5 times higher than after oral administration of melagatran. The variability in the area under the drug plasma concentration vs. time curve (AUC) is much smaller with oral H 376/95 (coefficient of variation 20%) than with oral melagatran (coefficient of variation 38%). Pharmacodynamic properties: H 376/95 is inactive towards human alpha-thrombin compared with melagatran [inhibition constant (K(i)) ratio, 185 times], a potential advantage for patients with silent gastrointestinal bleeding. In an experimental thrombosis model in the rat, oral H 376/95 was more effective than the subcutaneous low molecular weight heparin dalteparin in preventing thrombosis. CONCLUSION: By the use of the prodrug principle, H 376/95 endows the direct thrombin inhibitor melagatran with pharmacokinetic properties required for oral administration without compromising the promising pharmacodynamic properties of melagatran.

Administration, Oral↗

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.

Adolescent↗

No benefit of long-term ciprofloxacin treatment in patients with reactive arthritis and undifferentiated oligoarthritis: a three-month, multicenter, double-blind, randomized, placebo-controlled study.

OBJECTIVE: To investigate the effect of long-term antibiotic treatment in patients with reactive arthritis (ReA) and undifferentiated oligoarthritis. METHODS: One hundred twenty-six patients were treated with ciprofloxacin (500 mg twice a day) or placebo for 3 months, in a double-blind, randomized study. Of these patients, 104 (48 treated with ciprofloxacin and 56 treated with placebo) were valid for clinical evaluation: 55 were diagnosed as having ReA with a preceding symptomatic urogenic or enteric infection and 49 as having undifferentiated oligoarthritis. These 2 groups were randomized separately. The triggering bacterium was sought by serology and/or culture. The percentage of patients in remission after 3 months of treatment was chosen as the primary efficacy parameter. RESULTS: A triggering bacterium could be identified in 52 patients (50%): Chlamydia trachomatis in 13, Yersinia in 14, and Salmonella in 25. No patient was positive for Campylobacter jejuni or for Shigella. No difference in outcome was found between treatment with ciprofloxacin or placebo in the whole group or in subgroups of patients with ReA or undifferentiated oligoarthritis. No difference was seen in patients with a disease duration <3 months. Ciprofloxacin was not effective in Yersinia- or Salmonella-induced arthritis but seemed to be better than placebo in Chlamydia-induced arthritis. This difference was not significant, however, which might be due to the small sample size. CONCLUSION: Long-term treatment of ReA with ciprofloxacin is not effective; however, it might be useful in the subgroup of patients who have Chlamydia-induced arthritis. This has to be proven in a bigger study focusing on patients with Chlamydia-induced arthritis.

Adult↗

[Radiosynoviorthesis in the treatment plan of chronic inflammatory joint diseases].

UNLABELLED: The effectiveness of radiosynovirothesis in the local treatment of chronically inflammatory joint diseases, especially rheumatoid arthritis, was evaluated. SUBJECTS AND METHODS: Follow-up examinations of 415 joints in 115 patients up to 4.5 years after intraarticular application of beta-emitting yttrium-90, rhenium-186, and erbium-169 were evaluated. The examination protocol included estimation of joint circumference, range of active joint moving capability, fist-bending power, and radiological assessment of joint destruction. Subjective assessment of pain, swelling, and joint function by the patients was evaluated by means of a score with three levels. RESULTS: The mean range of active joint moving capability increased in all joint subgroups, compared with the initial examination, with exception of ankle joints examined more than 30 months after therapy. The mean joint circumference decreased in all joint subgroups. Good to excellent results were achieved in up to 66% of joints, satisfying results in up to 21%, and no improvement or further deterioration was noted in 13% according to subjective assessment by patients themselves. Treatment proved most effective in joints with poor or no alteration in X-ray examinations. CONCLUSIONS: In the local treatment of chronically inflammatory joint diseases--especially beyond systemic drug therapy and local corticoid therapy--, radiosynoviorthesis is a low-invasive method, which may provide long-term relief of pain and swelling as well as improvement of joint function.

Adult↗

Differential surface expression of HLA-DRB1 and HLA-DRB4 among peripheral blood cells of DR4 positive individuals.

Increasing interest in the functional consequences of differential expression of MHC class II molecules prompted us to examine the surface expression of HLA class II molecules on fresh peripheral blood mononuclear cells. Differential regulation of DR4 and DRB4 was shown for peripheral blood monocytes. In addition, DR4 expression is upregulated on B cells of patients suffering from chronic inflammation and is reduced under prednisolone-treatment. The expression levels of total DR molecules on a given cell type are almost identical comparing different haplotypes among non-RA controls, suggesting that the alpha-chain determines the level of surface expression. The present findings fit the hypothesis that the differential expression of HLA class II molecules is involved in regulation of the immune response and may thus contribute to determining susceptibility to immunological diseases.

Arthritis, Rheumatoid↗

Bacteria-specific lymphocyte proliferation in peripheral blood in reactive arthritis and related diseases.

The cellular immune response seems to be important for the pathogenesis of reactive arthritis (ReA) and a bacteria-specific lymphocyte proliferation (LP) is often found in synovial fluid (SF) of ReA patients. However, the role of the bacteria-specific LP in peripheral blood (PB) is less well defined. In this study, we investigated 215 paired samples of SF and PB from patients with ReA (n = 65), undifferentiated oligoarthritis (n = 133) and undifferentiated spondylarthropathy (n = 17) to analyse the LP in PB and SF in relation to time. In 24 out of 87 patients (27.6%) with a bacteria-specific LP in synovial fluid, a positive LP to the same bacterium was also found in PB. While a positive LP in SF was found most frequently in the first week of the arthritis, a positive LP in PB was detected in 45% of patients when investigated between weeks 2 and 4 after the onset of arthritis, but was rarely found very early and late in the course of the arthritis. The time point seems to be crucial for the investigation of an LP in PB in patients with ReA.

Adolescent↗