In the diagnosis of giant cell arteritis (GCA) with aortic involvement, ¹⁸F-FDG PET has been demonstrated to be a powerful tool. No other imaging method is able to directly detect acute inflammation within the aortic wall. However, because GCA is a rare PET indication, the assessment of GCA with ¹⁸F-FDG PET remains difficult and highly dependent on the experience of the investigator. This study aimed to semiquantify the relationship between aortic and liver uptake and to introduce a receiver operating characteristic (ROC)–based cutoff ratio to allow investigator- and experience-independent GCA diagnosis with optimal sensitivity and specificity. Ratios of aortic wall uptake versus liver uptake were calculated in a group of GCA patients and a control group. These data were assessed in an ROC analysis, and finally, a cutoff-ratio–optimizing strategy was applied. Methods: Twenty-three patients with initially suspected GCA (18 positive for GCA criteria, 5 negative) and 36 matched controls were included. The control subjects underwent PET for oncologic diagnostics. None had intrathoracic or hepatic disease or therapy-related tracer accumulation. Additionally, physiologic liver metabolism was ensured by the presence of normal liver enzymes. After defining regions of interest over the thoracic aorta and the liver, we calculated maximal standardized uptake value ratios. Sensitivities and specificities for cutoff ratios from 0.1 to 2.5 were estimated and were ultimately used to assess an optimal cutoff ratio for separating GCA patients from controls. To further investigate the usefulness of the resulting cutoff ratio, we tested it in a second control group with changed hepatic metabolism and elevated liver enzymes. Results: ROC analysis revealed optimal selectivity for a cutoff ratio of 1.0. This ratio led to a sensitivity of 88.9%, a specificity of 95.1%, and an accuracy of 94.4%. When this aorta-to-liver ratio was applied to the control group with pathologic liver metabolism, the resulting specificity was 95.6%. Conclusion: The ¹⁸F-FDG PET region-of-interest analysis with aorta-to-liver maximal standardized uptake value ratios is a reliable, investigator-independent indicator of GCA not affected by minor inflammation-associated changes in hepatic metabolism. Our results for a cutoff ratio of 1.0 prove that ¹⁸F-FDG PET is a method of high sensitivity and specificity for GCA-related large-vessel inflammation.

Objectives: To investigate infiltrated cells in the synovial fluid (SF) of inflamed joints of patients with rheumatoid arthritis (RA), with special reference to polymorphonuclear neutrophils (PMN) and their interaction with T cells. Methods: Expression on PMN of activation associated receptors CD14, CD64, CD83, and major histocompatibility complex (MHC) class II was examined in the SF of 15 patients with RA, as were the infiltrated T cells. SF cytokines were determined by enzyme linked immunosorbent assay (ELISA). To mimic the in vivo situation, co-culture experiments were carried out using PMN and T cells of healthy donors. Results: The SF contained activated T lymphocytes and abundant PMN. SF PMN expression of CD14 and CD64 was enhanced compared with peripheral blood. Of special interest was the observation that only the SF PMN expressed MHC class II antigens and CD83. Exposure to SF, which contained considerable amounts of cytokines (for example, interferon γ (IFNγ), tumour necrosis factor α, and interleukin 2), induced a similar receptor pattern on blood derived PMN of healthy donors. Furthermore, PMN acquired MHC class II and CD83 within 24 to 48 hours, when co-cultured with autologous T cells or T cell lines. This effect was also achieved by T cell supernatants, was dependent on protein synthesis, and could be inhibited by antibodies against IFNγ. Conclusions: SF PMN from patients with RA undergo major alterations, including transdifferentiation to cells with dendritic-like characteristics, probably induced by T cell derived cytokines. Because MHC class II positive PMN are known to activate T cells, the mutual activation of PMN and T cells might contribute to the perpetuation of the local inflammatory process, and eventually to the destructive process in RA.

Background: Joint involvement occurs in most patients with systemic lupus erythematosus (SLE), and severe lupus arthritis is often refractory to conventional treatments. Anakinra is used in the treatment of rheumatoid arthritis, but its therapeutic potential has not been proved in patients with SLE. Objective: To determine the safety/tolerability and efficacy of anakinra in patients with SLE with leading joint involvement. Methods: In patients with SLE with active polyarthritis and no other uncontrolled systemic/organ manifestations, 100 mg/day anakinra was self administered subcutaneously for 3 months. Disease activity was assessed by VAS, number of swollen/tender joints, ECLAM score, and serological and immunological measures. Results: Four patients with SLE were studied; anakinra was safe in all four patients and no drug related serious adverse events occurred. A subjective benefit was seen in all patients and a trend towards better activity measures after 4 weeks. After an initial response, one patient left the study because of an arthritic flare after 6 weeks. Conclusion: In this study anakinra was apparently safe and well tolerated and led to clinical and serological improvement. Anakinra might be an interesting alternative in individual patients with lupus arthritis not responding to conventional treatments.

Zusammenfassung: Hintergrund: Muskuloskelettale Symptome und Erkrankungen sind in der Bevölkerung sehr weit verbreitet und verursachen hohe Kosten in Gesundheitswesen und Volkswirtschaft. Ziel der Arbeit: Die Häufigkeit muskuloskelettaler Symptome und Erkrankungen aus den Bereichen Rückenschmerzen, Osteoporose, Arthrose und Arthritis wurde auf Basis von Daten der bevölkerungsbasierten NAKO Gesundheitsstudie beschrieben. Material und Methoden: Die Daten wurden in der ersten Hälfte der NAKO-Basiserhebung von März 2014 bis März 2017 bei Erwachsenen im Alter von 20–75 Jahren erhoben. In die Analysen gingen Daten von 101.779 Interviewteilnehmenden sowie von 9370 Teilnehmenden aus zwei klinischen Untersuchungen ein. Mittels der klinischen Handuntersuchung wurden tastbar geschwollene Gelenke sowie auf Druck schmerzhafte Gelenke identifiziert. Die Winkelstuhluntersuchung lieferte Daten zu Ruheschmerzen am Knie- und Hüftgelenk. Häufigkeiten wurden auf die deutsche Standardbevölkerung 2011 gewichtet. Ergebnisse: In den Selbstberichten der Teilnehmenden im Interview wurden am häufigsten jemals diagnostizierte andauernde Rückenschmerzen (22,5 %) und Arthrosen (20,6 %) angegeben, seltener Osteoporose (2,9 %) und rheumatoide Arthritis (1,9 %). In der Handuntersuchung wurden bei 6,0 % Schmerzen an mindestens einem Fingergelenk festgestellt. Laut Winkelstuhluntersuchung waren 8,2 % von einem Ruheschmerz in mindestens einem Knie betroffen sowie 5,1 % an der Hüfte. Frauen berichteten insgesamt häufiger muskuloskelettale Erkrankungen und Symptome als Männer, der Anteil Betroffener nahm mit dem Alter deutlich zu. Diskussion: Die Ergebnisse belegen die große Verbreitung vieler muskuloskelettaler Erkrankungen. Die berichtete Beschwerdelast ist mit Ergebnissen aus früheren bevölkerungsbezogenen Erhebungen vergleichbar.