Faculty Bibliography

The diagnosis and treatment of chronic obstructive pulmonary disease (COPD) has been based largely on a one-size-fits-all approach. Diagnosis of COPD is based on meeting the physiologic criteria of fixed obstruction in forced expiratory flows and treatment focus on symptomatic relief, with limited effect on overall prognosis. However, patients with COPD have distinct features that determine very different evolutions of the disease. In this review we highlight distinct subgroups of COPD characterized by unique pathophysiologic derangements, response to treatment, and disease progression. It is likely that identification of subgroups of COPD will lead to discovery of much needed disease-modifying therapeutic approaches. We argue that a precision approach that integrates multiple dimensions (clinical, physiologic, imaging, and endotyping) is needed to move the field forward in the treatment of this disease.

Objective: To characterize the gut microbiota and host gene interactions in Reactive Arthritis (ReA) and postinfectious SpA. Methods: 32 patients with ReA and 32 controls with preceding Gastrointestinal (GI) and/or Genitourinary (GU) infections that did not develop arthritiswere prospectively recruited in Guatemala, a highly prevalent geographic region for this disease. Clinical variables, HLA status and 16S ribosomal RNA gene sequencing of intestinal microbiota were analysed. Results: Subjects with ReA showed no significant differences from controls in gut bacterial richness, alpha or beta diversity. However there was a higher abundance of Erwinia and Pseudomonas, and increased prevalence of typical enteropathogens associated with ReA. In Fact, at least one enteropathogen was present in 71.9% of ReA subjects vs 46.8% of controls (p<0.05). Subjects with ultrasound evidence of enthesitiswere enriched with Campylobacter,while subjects with Uveitis and radiographic sacroiliitis were enriched with Erwinia and unclassified Ruminococcaceae, respectively. Both were enriched in Dialister (log LDA>2). Host genetics, particularly HLA-A24 were associated with differences in gut microbiota diversity irrespective of disease status. We identified several co-occurring taxa that were also predictive of HLA-A24 status, including Ruminococcaceae-Rikenellaceae-Coriobacteriacea and Prevotellaceaeunclassified Sphingobacteriales-Elusimicrobiaceae. Conclusion: This is the first culture-independent study characterizing the gut microbial community of ReA. Although bacterial factors correlated with disease presence and clinical features of ReA, host genetics also appeared to be a major independent driver of intestinal community composition. Understanding of these gut microbiota host-genetic relationships may further clarify the pathogenesis of ReA and related Spondyloarthritis

Changes in lung microbiota associated with smoking might contribute to the development of acute respiratory distress syndrome in subjects with blunt trauma.

OBJECTIVE: Reactive arthritis (ReA) is an inflammatory disorder occurring several weeks after gastrointestinal or genitourinary infections. HLA-B27 positivity is considered a risk factor, though not necessarily predictive of disease incidence. Among non-genetic factors, the intestinal microbiome may play a role in disease susceptibility. The objective of this study was to characterize the gut microbiota and host gene interactions in ReA and post-infectious spondyloarthritis. METHODS: Adult peripheral spondyloarthritis and control subjects with preceding infections that did not develop arthritis were prospectively recruited from a highly prevalent geographic region. Clinical variables, HLA status, and 16S rRNA gene sequencing of intestinal microbiota were analyzed. RESULTS: ReA subjects showed no significant differences from controls in gut bacterial richness or diversity. However, there was a significantly higher abundance of Erwinia and Pseudomonas, and increased prevalence of typical enteropathogens associated with ReA. Subjects with ultrasound evidence of enthesitis were enriched in Campylobacter, while subjects with uveitis and radiographic sacroiliitis were respectively enriched in Erwinia and unclassified Ruminococcaceae, and both enriched in Dialister. Host genetics, particularly HLA-A24, were associated with differences in gut microbiota diversity irrespective of disease status. We determined several co-occurring taxa that were also predictive of HLA-A24 status. CONCLUSION: This is the first culture-independent study characterizing the gut microbial community of post-infectious arthritis. Although bacterial factors correlated with disease presence and clinical features of ReA, host genetics also appeared to be a major independent driver of intestinal community composition. Understanding of these gut microbiota host-genetic relationships may further clarify the pathogenesis of post-infectious spondyloarthropathies.