Abstract: Macrophage activation syndrome (MAS) is a life-threatening complication of systemic juvenile idiopathic arthritis (sJIA) characterised by a vicious cycle of immune amplification that can culminate in overwhelming inflammation and multiorgan failure. The clinical features of MAS overlap with those of active sJIA, complicating early diagnosis and treatment. We evaluated adenosine deaminase 2 (ADA2), a protein of unknown function released principally by monocytes and macrophages, as a novel biomarker of MAS. Methods We established age-based normal ranges of peripheral blood ADA2 activity in 324 healthy children and adults. We compared these ranges with 173 children with inflammatory and immune-mediated diseases, including systemic and non-systemic JIA, Kawasaki disease, paediatric systemic lupus erythematosus and juvenile dermatomyositis. Results ADA2 elevation beyond the upper limit of normal in children was largely restricted to sJIA with concomitant MAS, a finding confirmed in a validation cohort of sJIA patients with inactive disease, active sJIA without MAS or sJIA with MAS. ADA2 activity strongly correlated with MAS biomarkers including ferritin, interleukin (IL)-18 and the interferon (IFN)-γ-inducible chemokine CXCL9 but displayed minimal association with the inflammatory markers C reactive protein and erythrocyte sedimentation rate. Correspondingly, ADA2 paralleled disease activity based on serial measurements in patients with recurrent MAS episodes. IL-18 and IFN-γ elicited ADA2 production by peripheral blood mononuclear cells, and ADA2 was abundant in MAS haemophagocytes. Conclusions These findings collectively identify the utility of plasma ADA2 activity as a biomarker of MAS and lend further support to a pivotal role of macrophage activation in this condition.

Abstract: To compare clinical outcomes in children with hemophagocytic lymphohistiocytosis (HLH) and macrophage activation syndrome (MAS) who were managed before and after implementation of an evidence-based guideline (EBG). Methods A management algorithm for MAS-HLH was developed at our institution based on literature review, expert opinion, and consensus building across multiple pediatric subspecialties. An electronic medical record search retrospectively identified hospitalized patients with MAS-HLH in the pre-EBG (October 15, 2015, to December 4, 2017) and post-EBG (January 1, 2018, to January 21, 2020) time periods. Predetermined outcome metrics were evaluated in the 2 cohorts. Results After the EBG launch, 57 children were identified by house staff as potential patients with MAS-HLH, and rheumatology was consulted for management. Ultimately, 17 patients were diagnosed with MAS-HLH by the treating team. Of these, 59% met HLH 2004 criteria, and 94% met 2016 classification criteria for MAS complicating systemic juvenile idiopathic arthritis. There was a statistically significant reduction in mortality from 50% before implementation of the EBG to 6% in the post-EBG cohort ( P = 0.02). There was a significant improvement in time to 50% reduction in C-reactive protein level in the post-EBG vs pre-EBG cohorts (log-rank P 〈 0.01). There were trends toward faster time to MAS-HLH diagnosis, faster initiation of immunosuppressive therapy, shorter length of hospital stay, and more rapid normalization of MAS-HLH–related biomarkers in the patients post-EBG. Conclusion While the observed improvements may be partially attributed to advances in treatment of MAS-HLH that have accumulated over time, this analysis also suggests that a multidisciplinary treatment pathway for MAS-HLH contributed meaningfully to favorable patient outcomes.

Abstract: Cancers arising from gastrointestinal epithelial cells are common, aggressive, and difficult to treat. Progress in this area resulted from recognizing that the biological behavior of these cancers is highly dependent on bioactive molecules released by neurocrine, paracrine, and autocrine mechanisms within the tumor microenvironment. For many decades after its discovery as a neurotransmitter, acetylcholine was thought to be synthesized and released uniquely from neurons and considered the sole physiological ligand for muscarinic receptor subtypes, which were believed to have similar or redundant actions. In the intervening years, we learned this former dogma is not tenable. (1) Acetylcholine is not produced and released only by neurons. The cellular machinery required to synthesize and release acetylcholine is present in immune, cancer, and other cells, as well as in lower organisms (e.g., bacteria) that inhabit the gut. (2) Acetylcholine is not the sole physiological activator of muscarinic receptors. For example, selected bile acids can modulate muscarinic receptor function. (3) Muscarinic receptor subtypes anticipated to have overlapping functions based on similar G protein coupling and downstream signaling may have unexpectedly diverse actions. Here, we review the relevant research findings supporting these conclusions and discuss how the complexity of muscarinic receptor biology impacts health and disease, focusing on their role in the initiation and progression of gastric, pancreatic, and colon cancers.

Abstract: Minimally invasive surgical techniques are routinely promoted as alternatives to open surgery because of improved outcomes. However, the impact of robotic surgery on certain subsets of the population, such as frail patients, is poorly understood. OBJECTIVE: The purpose of our study was to examine the association between frailty and minimally invasive surgical approaches with colon cancer surgery. DESIGN: This is a retrospective study of prospectively collected outcomes data. Thirty-day surgical outcomes were compared by frailty and surgical approach using doubly robust multivariable logistic regression with propensity score weighting, and testing for interaction effects between frailty and surgical approach. SETTING: Patients undergoing an open, laparoscopic, or robotic colectomy for primary colon cancer, 2012 to 2016, were identified from the American College of Surgeons National Surgical Quality Improvement Program database. PATIENTS: Patients undergoing a colectomy with an operative indication for primary colon cancer were selected. MAIN OUTCOME MEASURES: The primary outcomes measured were 30-day postoperative complications. RESULTS: After propensity score weighting of patients undergoing colectomy, 33.8% (n = 27,649) underwent an open approach versus 34.3% (n = 28,058) underwent laparoscopic surgery versus 31.9% (n = 26,096) underwent robotic surgery. Robotic (OR, 0.53; 95% CI, 0.42–0.69, p 〈 0.001) and laparoscopic (OR, 0.58; 95% CI, 0.52–0.66, p 〈 0.001) surgeries were independently associated with decreased rates of major complications. Frailer patients had increased complication rates (OR, 1.56; 95% CI, 1.07–2.25, p = 0.018). When considering the interaction effects between surgical approach and frailty, frailer patients undergoing robotic surgery were more likely to develop a major complication (combined adjusted OR, 3.15; 95% CI, 1.34–7.45, p = 0.009) compared with patients undergoing open surgery. LIMITATIONS: Use of the modified Frailty Index as an associative proxy for frailty was a limitation of this study. CONCLUSIONS: Although minimally invasive surgical approaches have decreased postoperative complications, this effect may be reversed in frail patients. These findings challenge the belief that robotic surgery provides a favorable alternative to open surgery in frail patients. See Video Abstract at http://links.lww.com/DCR/B163. LOS PACIENTES MÁS FRÁGILES SOMETIDOS A COLECTOMÍA ROBÓTICA POR CÁNCER DE COLON EXPERIMENTAN MAYORES TASAS DE COMPLICACIONES EN COMPARACIÓN CON ABORDAJES LAPAROSCÓPICO O ABIERTO ANTECEDENTES: Las técnicas quirúrgicas mínimamente invasivas estan frecuentement promovidas como alternativas a la cirugía abierta debido a sus mejores resultados. Sin embargo, el impacto de la cirugía robótica en ciertos subgrupos de población, como el caso de los pacientes endebles, es poco conocido. OBJETIVO: El propósito de nuestro estudio fue examinar la asociación entre la fragilidad de los pacientes y el aborgaje quirúrgico mínimamente invasivo para la cirugía de cáncer de colon. DISEÑO: Estudio retrospectivo de datos de resultados recolectados prospectivamente. Los resultados quirúrgicos a 30 días se compararon entre fragilidad y abordaje quirúrgico utilizando la regresión logística multivariable doblemente robusta con ponderación de puntaje de propensión y pruebas de efectos de interacción entre fragilidad y abordaje quirúrgico. LUGAR: Los pacientes identificados en la base de datos del Programa Nacional de Mejora de la Calidad Quirúrgica del Colegio Estadounidense de Cirujanos, que fueron sometidos a una colectomía abierta, laparoscópica o robótica por cáncer de colon primario, de 2012 a 2016. PACIENTES: Todos aquellos pacientes seleccionados con indicación quirúrgica de cáncer primario de colon que fueron sometidos a una colectomía. PRINCIPALES MEDIDAS DE RESULTADO: Las complicaciones postoperatorias a 30 días. RESULTADOS: Luego de ponderar el puntaje de propensión de los pacientes colectomizados, el 33.8% (n = 27,649) fué sometido a laparotomía versus el 34.3% (n = 28,058) operados por laparoscopía versus el 31.9% (n = 26,096) operados con tecnica robótica. Las cirugías robóticas (OR 0.53, IC 95% 0.42–0.69, p 〈 0.001) y laparoscópicas (OR 0.58, IC 95% 0.52–0.66, p 〈 0.001) se asociaron de forma independiente con una disminución de las tasas de complicaciones mayores. Los pacientes más delicados tenían mayores tasas de complicaciones (OR 1.56, IC 95% 1.07–2.25, p = 0.018). Al considerar los efectos de interacción entre el abordaje quirúrgico y la fragilidad, los pacientes más débiles sometidos a cirugía robótica tenían más probabilidades de desarrollar una complicación mayor (OR ajustado combinado 3.15, IC 95% 1.34–7.45, p = 0.009) en comparación con los pacientes sometidos a cirugía abierta. LIMITACIONES: El uso del índice de fragilidad modificado como apoderado asociativo de la fragilidad. CONCLUSIONES: Si bien los abordajes quirúrgicos mínimamente invasivos han disminuido las complicaciones postoperatorias, este efecto puede revertirse en pacientes lábiles. Estos hallazgos desafían la creencia de que la cirugía robótica proporciona una alternativa favorable a la cirugía abierta en pacientes frágiles. Consulte Video Resumen en http://links.lww.com/DCR/B163. (Traducción—Dr. Xavier Delgadillo )

Abstract: Despite structural similarity, the five subtypes comprising the cholinergic muscarinic family of G protein-coupled receptors regulate remarkably diverse biological functions. This mini review focuses on the closely related and commonly co-expressed M 1 R and M 3 R muscarinic acetylcholine receptor subtypes encoded respectively by CHRM1 and CHRM3 . Activated M 1 R and M 3 R signal via G q and downstream initiate phospholipid turnover, changes in cell calcium levels, and activation of protein kinases that alter gene transcription and ultimately cell function. The unexpectedly divergent effects of M 1 R and M 3 R activation, despite similar receptor structure, distribution, and signaling, are puzzling. To explore this conundrum, we focus on the gastrointestinal (GI) tract and liver because abundant data identify opposing effects of M 1 R and M 3 R activation on the progression of gastric, pancreatic, and colon cancer, and liver injury and fibrosis. Whereas M 3 R activation promotes GI neoplasia, M 1 R activation appears protective. In contrast, in murine liver injury models, M 3 R activation promotes and M 1 R activation mitigates liver fibrosis. We analyze these findings critically, consider their therapeutic implications, and review the pharmacology and availability for research and therapeutics of M 1 R and M 3 R-selective agonists and antagonists. We conclude by considering gaps in knowledge and other factors that hinder the application of these drugs and the development of new agents to treat GI and liver diseases.