Gastrointestinal (GI) manifestations of rheumatoid arthritis (RA) are rare, but can be impactful for patients. Some GI processes are directly related to RA, whereas others may be sequelae of treatment or caused by concomitant autoimmune diseases. This article discusses the role of the GI tract in RA pathogenesis; the presentation, epidemiology, and diagnosis of RA-related GI manifestations; concomitant GI autoimmune diseases that may affect those with RA; and GI side effects of RA treatment. The importance of appropriately considering conditions unrelated to RA in the differential diagnosis when evaluating new GI symptoms in patients with RA is noted.

TrkB, the cognate receptor for brain-derived neurotrophic factor and neurotrophin-4, has been implicated in regulating synapse formation in the central nervous system. Here we asked whether TrkB plays a role in the maturation of the climbing fibre-Purkinje cell (CF-PC) synapse. In rodent cerebellum, Purkinje cells are initially innervated by multiple climbing fibres that are subsequently culled to assume the mature mono-innervated state, and whose contacts translocate from the soma to the dendrites. By employing transgenic mice hypomorphic or null for TrkB expression, our results indicated that perturbation of TrkB in the immature cerebellum resulted in ataxia, that Purkinje cells remained multiply innervated by climbing fibres beyond the normal developmental time frame, and that synaptic transmission at the parallel fibre-Purkinje cell synapse remained functionally unaltered. Mechanistically, we present evidence that attributes the persistence of multiple climbing fibre innervation to an obscured discrimination of relative strengths among competing climbing fibres. Soma-to-dendrite translocation of climbing fibre terminals was unaffected. Thus, TrkB regulates pruning but not translocation of nascent CF-PC synaptic contacts.

Objective.The Psoriatic Arthritis (PsA) Core Domain Set for randomized controlled trials and longitudinal observational studies has recently been updated. The joint counts are central to the measurement of the peripheral arthritis component of the musculoskeletal (MSK) disease activity domain. We report the Outcome Measures in Rheumatology (OMERACT) 2018 meeting’s approaches to seek endorsement of the 66/68 swollen and tender joint count (SJC66/TJC68) for inclusion in the PsA Core Outcome Measurement Set (COS).Methods.Using the OMERACT Filter 2.1 Instrument Selection Process, the SJC66/TJC68 was assessed for (1) domain match, (2) feasibility, (3) numerical sense (construct validity), and (4) discrimination (test retest reliability, longitudinal construct validity, sensitivity in clinical trials, and thresholds of meaning). A protocol was designed to assess the measurement properties of the SJC66/TJC68 joint count. The results were summarized in a Summary of Measurement Properties table developed by OMERACT. OMERACT members discussed and voted on whether the strength of the evidence supported that the SJC66/TJC68 had passed the OMERACT Filter as an outcome measurement instrument for the PsA COS.Results.OMERACT delegates endorsed the use of the SJC66/TJC68 for the measurement of the peripheral arthritis component of the MSK disease activity domain. Among patient research partners, 100% voted for a “green” endorsement, whereas among the group of other stakeholders, 88% voted for a “green” endorsement.Conclusion.The SJC66/TJC68 is the first fully endorsed outcome measurement instrument using the OMERACT Filter 2.1 and the first instrument fully endorsed within the PsA COS.

Hereditary angioedema (HAE) is an autosomal dominant disease characterized by deficiency of C1 inhibitor (C1-INH) that commonly presents with recurrent swelling affecting different parts of the body. Supplementation with C1-INH is successfully used to treat HAE in selected countries, mostly in Europe. Berinert P (CSL Behring, Marburg, Germany), a human plasma-derived C1-INH, was studied in the International Multicenter Prospective Angioedema C1-inhibitor Trial 1 (IMPACT1) that was completed in 2007. It was the first safety and dose-finding study of C1-INH in patients with acute abdominal and facial angioedema. IMPACT2 was the extension of the first trial to study C1-INH efficacy and safety in multiple treatments of acute HAE attacks in various areas of the body. Berinert P has excellent potential to become a first-line therapy for treating patients with acute HAE attacks in the USA and other countries involved in the IMPACT trials. While final data from the IMPACT2 trial are not yet released, this article reviews currently available data from previous reports and abstract presentations.