Ernesto de Meis MD PhD, Biatriz C. Brandão MD, Fernanda C. Capella MD , José A.P. Garcia MD and Simone C. Gregory MD
Thrombosis is a common phenomenon in patients with malignancies. It is believed that thrombosis is multifactorial and that in addition to mechanisms directly associated with cancer and its treatment, it may also be related to the interaction between the immune system and clotting. The present work describes four cancer patients (three adults and one child) whose clinical course was characteristic of catastrophic antiphospholipid syndrome (CAPS) in intensive care units of the National Cancer Institute of Rio de Janeiro. The presence of findings similar to those in CAPS can be attributed to an unbalanced interaction between the immune system and coagulation.
Maria G. Lazzaroni MD, Marco Taglietti MD and Angela Tincani MD
Ignasi Rodríguez-Pintó MD, Alessandra. Soriano MD, Gerard Espinosa MD PhD, Yehuda Shoenfeld MD FRCP and Ricard Cervera MD PhD FRCP
Smadar Gertel MD and Howard Amital MD MHA
The major autoantigens in the inflamed synovium in rheumatoid arthritis (RA) are citrullinated peptides. Citrullinated peptides are employed in diagnostic kits for detection of anti-citrullinated protein antibodies (ACPA), a serological marker with high specificity and sensitivity in the diagnosis of RA, and have been included in the new ACR/EULAR classification criteria for RA. ACPA-positive RA patients suffer from an erosive and more aggressive disease compared to ACPA-negative patients. In view of the mounting indications that ACPA plays a seminal role in the pathogenesis of RA, it might be valuable to pursue a specific treatment aiming ACPA as a target. We found that citrullinated peptides, which contain a unique amino acid, citrulline, alter the protein structure within the connective tissue, leading to tolerance breakdown and triggering the autoimmune response in RA. However, with different doses and routes of administration, citrullinated peptides can promote immune tolerance rather than induction of disease.