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Henning Zeidler

Publications and source records attributed to Henning Zeidler.

34 records · Page 2Linked to original sources

Cost-effectiveness of TNF-alpha-blocking agents in the treatment of rheumatoid arthritis.

The current literature covering cost-effectiveness and cost-utility analyses of biological treatments in patients with rheumatoid arthritis (RA) are reviewed in order to discuss options and limitations for future application of these highly priced drugs in routine clinical practice. The cost-effectiveness and cost-utility ratios of the studies analysed are converted into the corresponding Euros of the publication year. Etanercept treatment achieved a cost-effectiveness ratio of 44,300 Euros (2002)/ACR 20 (20% response according to American College of Rheumatology criteria) and 43,100 Euros (2002)/ACR 70WR (ACR 70 weighted response) compared with sulfasalazine and methotrexate, respectively, in methotrexate-naive RA. In methotrexate-resistant RA, the combination of etanercept and methotrexate is compared to a combination therapy of methotrexate, sulfasalazine and hydroxychloroquine revealing costs of 46,100 Euros (2000)/ACR 20, and 37,700 Euros/ACR 70WR. The cost-utility ratios for infliximab treatment range from 16,000 Euros to almost 166,000/QALY (quality adjusted life-year) gained, the studies investigating etanercept treatment show a ratio of approximately 25,000 Euros and 120,000/QALY gained. No substantial differences of cost-utilities of infliximab and etanercept were found. The administration of these drugs as third-line therapy is regarded cost-effective compared to other well-accepted therapies with comparable cost-utility ratios of < 50,000 Euros/QALY gained. Still, data on economic outcomes of RA trials are sparse and further cost-effectiveness and cost-utility evaluations are needed.

Adalimumab↗

Improvement of Erdheim-Chester disease in two patients by sequential treatment with vinblastine and mycophenolate mofetil.

Erdheim-Chester disease (ECD) is a rare non-Langerhans' form of histiocytosis with a plethora of different clinical manifestations owing to multiple organ involvement. We report two patients who presented initially with different clinical symptoms. The presenting complaint of the first patient was bone pain, predominantly in the legs, whereas in the other patient the initial symptoms were related to obstruction of both ureters, as in idiopathic retroperitoneal fibrosis. Ultimately, ECD was diagnosed in both patients by the occurrence of both pathognomonic manifestations, the histologic presence of non-Langerhans' histiocytes in bone biopsies, and osteosclerotic lesions of the long bones. Because the extraosseous manifestations progressed and a single application of corticosteroids was ineffective, sequential treatment with vinblastine and mycophenolate mofetil, together with prednisolone, was started. At follow-up respectively 15 and 16 months after the start of treatment a beneficial effect was noted in both patients. These cases illustrate the clinical spectrum of ECD, detail the pathognomonic manifestations of this rare disease, emphasize the need to consider ECD as an uncommon but important differential diagnosis in patients with arthralgias or systemic fibrosis, and give the first evidence for a new treatment option.

Antineoplastic Agents, Phytogenic↗

Cytokine profile in serum and synovial fluid of arthritis patients with Chlamydia trachomatis infection.

Chlamydia trachomatis (Ct)-induced arthritis (CtIA) is characterized by persistent Ct infection, which stimulates secretion of cytokines in vitro. We therefore investigated whether CtIA patients have a unique cytokine profile in synovial fluid or serum in vivo. Because underlying Ct infection is overlooked in a high percentage of patients with initially diagnosed undifferentiated oligoarthritis (UOA), we examined whether determination of cytokines might also be of diagnostic relevance for this arthritis form. Matched serum and synovial fluid specimens from 26 patients with CtIA were analyzed and compared to those from 34 patients with UOA in whom Ct infection was excluded and those of nine patients with rheumatoid arthritis (RA). In 15 CtIA patients, Ct DNA from synovial fluid could be amplified by polymerase chain reaction. The following cytokine or cytokine antagonists were measured by enzyme-linked immunosorbent assay: interleukin (IL)-1beta, tumor necrosis factor (TNF)-alpha, IL-6, IL-1 receptor antagonist, and soluble TNF receptor p75. No statistically significant differences in cytokine levels between patients with CtIA or the other arthritis forms were detected. Also, comparison between CtIA patients with (n = 17) and without Chlamydia DNA (n = 9) in synovial fluid revealed no significant differences for these cytokines. Cytokine levels in serum and synovial fluid were not different between CtIA, UOA without Ct infection, and RA patients. The intracellular presence of Ct was not associated with a specific profile of these cytokines in vivo.

Adult↗

Chlamydia trachomatis-infected macrophages induce apoptosis of activated T cells by secretion of tumor necrosis factor-alpha in vitro.

Chlamydia trachomatis-infected macrophages induce T cell apoptosis. This ability might promote intracellular survival of Chlamydia and perpetuate chronic chlamydial infection. The purpose of this study was to examine the molecular mechanisms by which C. trachomatis-infected macrophages induce T cell apoptosis. Monocytes and T cells were isolated from the peripheral blood of healthy donors. Macrophages were infected with C. trachomatis, and autologous T cells were stimulated by mitogen. After 6 days, both populations were cultured together using a two-chamber transwell membrane system to differentiate between mechanisms involving either cell-to-cell contact or secretion of apoptotic factors. Apoptotic T cells were identified by propidium iodide through-flow cytometry, and tumor necrosis factor-alpha (TNF-alpha) concentrations were measured by enzyme-linked immunosorbent assay. Antagonists of TNF-alpha, the Fas (CD95) molecule, TNF-related apoptosis-inducing ligand (TRAIL), and catalase were added to differentiate between the pathways of apoptosis. C. trachomatis-infected macrophages significantly induced T cell apoptosis by cell-to-cell contact (mean +/- standard deviation, 30+/-4%; P<0.001) and by humoral mechanisms (mean +/- standard deviation, 22+/-3%, P<0.001). Humoral apoptosis was mediated by secretion of TNF-alpha from infected macrophages. Inhibition of secretory TNF-alpha by the monoclonal anti-TNF-alpha antibody adalimumab (D2E7) blocked T cell death in vitro. In contrast, T cell apoptosis mediated by cell-to-cell contact was not inhibited by the different anti-apoptotic reagents. In summary, TNF-alpha derived from infected macrophages is an important apoptosis factor for T cell apoptosis induced by C. trachomatis-infected cells.

Adalimumab↗

Diagnostic management of patients with SAPHO syndrome: use of MR imaging to guide bone biopsy at CT for microbiological and histological work-up.

Propionibacterium acnes (P. acnes) is suspected to be involved in the pathophysiology of SAPHO syndrome, since it has been isolated repeatedly through open surgical bone biopsy. This study demonstrates the role of MRI in identifying inflamed bone areas in patients with SAPHO syndrome and the role of CT-guided bone biopsies in obtaining samples from these areas for microbiological and histopathological investigations, thus obviating open surgery. Fourteen consecutive patients with SAPHO syndrome were investigated by MRI to identify acute inflammatory changes in hyperostotic periarticular bone. The CT-guided biopsies for microbiological investigations were taken from the areas identified. Patients positive for P. acnes were started on long-term antibiotic therapy according to antibiotic susceptibility. On MRI the inflammatory changes appeared as hyperintense areas on fat-saturated T2 fast-spin-echo (FSE) images and showed signal increase on fat-saturated T1 SE images after Gd-DTPA. With MR localization CT-guided bone biopsies yielded P. acnes in 8 patients. No bacteria could be isolated from the remaining 6 patients. Acute inflammatory bone changes in SAPHO syndrome are well localized by MRI. With MR localization, CT-guided bone biopsies offer a minimally invasive alternative to open surgery in the detection of. P. acnes leading to the institution of a specific antibiotic therapy.

Acquired Hyperostosis Syndrome↗

How does Chlamydia cause arthritis?

Because the bacterial cause of CIA has been identified and proven to persist at the site of inflammation, the understanding of how Chlamydia cause arthritis has made much progress. The site of entry and the route of dissemination have been identified, the molecular state of persistence is increasingly described, some mechanisms of how Chlamydia can persist despite an actively reacting immune system have been identified, and data regarding how persistent Chlamydia induce inflammation have been obtained. What needs to be achieved in the future--in addition to better understanding the molecular basis of persistence--is to reveal how persisting bacteria can be eliminated. If this information is insufficient for a cure of the disease, it must be determined how the inflammation can be treated more specifically and effectively to cure CIA early and prevent the development of chronic forms that develop into spondyloarthritis.

Arthritis, Reactive↗

[The European Regional Cooperative Centers for rheumatic diseases: a nation-wide network of interdisciplinary rheumatic care]].

The organisation of regional co-operative centres for rheumatic diseases was supported by a grant from the German Ministry of Health from 1992 to 1998, which aimed to improve the management of patients with chronic rheumatic diseases. After establishing the centres formal structures the major task was to improve quality of care by co-ordination and co-operation of all the institutions and health care providers involved in the management of rheumatic patients. For all these activities to be continued the regional co-operative centres for rheumatic diseases were integrated in the German Society of Rheumatology as one of its working groups in 1996. The major objective is the quality management of rheumatic care including a uniform patient documentation (the so-called core documentation), a thesaurus of diagnoses and the nation-wide use of a patient passport. Most importantly, guidelines for diagnosis and therapy were developed and especially adapted for use by patients and primary care physicians. Five project working groups (guidelines for diagnosis and therapy, documentation, quality management, paediatric rheumatology, physical medicine and rehabilitation) were established to work on future initiatives. Quality management is further supported and intensified by annual scientific workshops. In addition, the regional co-operative centres for rheumatic diseases are engaged in research and an important partner of the German Competence Network Rheumatic Diseases. Based on the established structures the horizontal and vertical network should be further involved in general medical care and should intensify the interaction with clinical and basic research.

Documentation↗

Microbe-induced T cell apoptosis: subversion of the host defense system?

Cells of multicellular organisms are equipped with a self destruction program called apoptosis to ensure homeostasis of the organism. Contraction of the lymphocyte compartment following recovery from an infection is controlled by this mechanism. But apoptosis of lymphocytes might be an Achilles tendon accessible to microbes to subvert the immune system. Evidence is cumulating that microbes use this mechanism to destroy microbe-specific T cells. We present an overview of microbe-induced T cell apoptosis discussing the consequences for the pathogenesis of microbial infection. The conventional role of lymphocytes during infection is to impose apoptotic threat to infected cells, the subject of this review highlights the opposite, lymphocytes as targets of microbe-induced death.

Animals↗

Chlamydia trachomatis genes whose products are related to energy metabolism are expressed differentially in active vs. persistent infection.

The Chlamydia trachomatis genome encodes glycolysis and pentose phosphate pathway enzymes, two ATP/ADP exchange proteins, and other energy transduction-related components. We asked if and when chlamydial genes specifying products related to energy transduction are expressed during active vs. persistent infection in in vitro models and in synovia from Chlamydia-associated arthritis patients. Hep-2 cells infected with K serovar were harvested from 0-48 h post-infection (active infection). Human monocytes identically infected were harvested at 1, 2, 3, 5 days post-infection (persistent). RNA from each preparation and from synovial samples PCR-positive/-negative for Chlamydia DNA was subjected to RT-PCR targeting (a) chlamydial primary rRNA transcripts and adt1 mRNA, (b) chlamydial mRNA encoding enzymes of the glycolysis (pyk, gap, pgk) and pentose phosphate (gnd, tal) pathways, the TCA cycle (mdhC, fumC), electron transport system (cydA, cydB), and sigma factors (rpoD, rpsD, rpoN). Primary rRNA transcripts and adt1 mRNA were present in each infected preparation and patient sample; controls were negative for chlamydial RNA. In infected Hep-2 cells, all energy transduction-related genes were expressed by approximately 11 h post-infection. In monocytes, pyk, gap, pgk, gnd, tal, cydA mRNA were present in 1-2-day-infected cells but absent at 3 days and after; cydB, mdhC, fumC were expressed through 5 days post-infection. RT-PCR targeting mRNA from sigma factor genes indicated that lack of these gene products cannot explain selective transcriptional down-regulation during persistence. Analyses of RNA from synovial tissues mirrored those from the monocyte system. These data suggest that in the first phase of active chlamydial infection, ADP/ATP exchange provides energy required for metabolism; in active growth, glycolysis supplements host ATP. In persistence host, rather than bacterially produced, ATP is the primary energy source. Metabolic rate in persistent C. trachomatis is lower than in actively growing cells, as judged from assays for relative chlamydial primary rRNA transcript levels in persistent vs. actively growing cells.

Adenosine Triphosphate↗

Prescription and tolerability of meloxicam in day-to-day practice: postmarketing observational cohort study of 13,307 patients in Germany.

The goal of this study was to obtain data for prescription habits, tolerability for patients at high risk, and clinical effectiveness of meloxicam administered at 7.5 mg and 15 mg for various rheumatic diseases under real world prescribing conditions. This was a 3-month large-scale prospective observational cohort study in 4000 medical practices throughout Germany shortly after the introduction of meloxicam. To be eligible, patients had to have a diagnosis of acute or chronic active rheumatic disease for which nonsteroidal antiinflammatory drug (NSAID) therapy was required according to the prescribing information. In this study, 13,307 patients receiving meloxicam prescriptions (7.5 mg in 65% and 15 mg in 33%) were observed. The diagnoses of these patients included osteoarthritis (61%), rheumatoid arthritis (24%), ankylosing spondylitis (1.6%), and other rheumatic conditions (28%). A substantial proportion of high risk patients were enrolled: 12% with a previous history of a perforation, ulceration, and bleeding (PUB), 24% with at least one concomitant cardiovascular disorder, and 26% receiving concomitant antihypertensive medication. Many of the patients (58%) had received NSAIDs before meloxicam, including patients with insufficient prior treatment effectiveness (43%) and those with NSAID-related adverse drug reactions (21%). In 85% and 94% of the patients, respectively, effectiveness and tolerability were rated as good or very good. Quality of life and daily functions improved in 64% to 84% of the patients. Only 0.8% of the patients reported gastrointestinal (GI) adverse drug reactions. Four uncomplicated cases of gastric ulceration, one serious perforated gastric ulcer, and one serious ileus complication were reported after incorrect use or overdosing of meloxicam. Treatment with the selective cyclooxygenase-2 (COX-2) inhibitor meloxicam in doses of 7.5 mg and 15 mg resulted in meaningful treatment responses under real life conditions, despite inclusion of a substantial number of patients with insufficient effectiveness of previous use of non-COX-2 selective NSAIDs. All major GI toxicity (PUB) observed was owing to the fact that prescribing conditions were not respected appropriately. Despite a selection of high risk patients overall, GI, cardiovascular, and renal tolerability was favorable.

Journal Article↗

Ro 15-8081 in osteoarthritis of hip and knee: a double-blind placebo-controlled multicentre dose-ranging study on analgesia.

Ro 15-8081, a substituted cyclohexanol hydrochloride, inhibits the re-uptake of norepinephrine and of serotonin. Its antinociceptive properties have been demonstrated in animals and then confirmed in humans after single-dose administration. The objective was to determine the analgesic efficacy and the safety of Ro 15-8081 in osteoarthritis of the hip and knee (femoro-tibial location) after multiple-dose application. The design for studying dosage employed 5 parallel groups in an international multicenter, double-blind, randomized trial having a duration of 2 weeks. Drugs studied were: 20 mg Ro 15-8081 (divided into 2 doses), 50 mg Ro 15-8081 (divided into 2 doses), 100 mg Ro 15-8081 (divided into 2 doses), placebo twice daily or 20 mg/day piroxicam (piroxicam in the morning and placebo in the evening). Piroxicam was used as a reference drug in order to validate clinical testing. Assessment criteria were pain (100-mm VAS) and function (Lequesne's index). A responder (main assessment criterion) was defined as a patient exhibiting a reduction of at least 30% of pain (VAS) during the study (intention-to-treat analysis). A total of 522 patients were enrolled in the study. A clear beneficial effect of piroxicam was observed when compared with placebo (70% and 48% of responders in piroxicam and placebo groups respectively; P < 0.0001). Multigroup comparison showed a statistically significant difference between Ro 15-8081 groups and the placebo group regarding mean change in pain between D1 and Dend and the rate of VAS responders. Comparison (Dunnett's t or chi 2 tests) between each individual Ro 15-8081 and the placebo group reached statistical significance for the 100 mg Ro 15-8081 group (mean change in pain between D1 and Dend: P = 0.05; percentage of responders: P = 0.0008) but no statistically significant difference for the other dosages of Ro 15-8081. Fifty-three patients withdrew from the study because of adverse events and/or inefficacy, mainly in 50 and 100 mg Ro 15-8081 groups and in a dose-related manner. The adverse events which appeared to be drug related were mainly dryness of the mouth, insomnia, headache, constipation, nausea, dizziness, nervousness, palpitation. This study suggests that 100 mg Ro 15-8081 per day divided into 2 doses has (1) an analgesic effect in hip or knee osteoarthritis and (2) poor acceptability in the conditions of the study regimen application.

Aged↗