Confocal laser endomicroscopy reveals alterations in duodenal permeability in patients with acute pancreatitis

The Multifaceted Role of Confocal Laser Endomicroscopy in Head and Neck Surgery: Oncologic and Functional Insights

(1) Background: Confocal laser endomicroscopy (CLE) has emerged as a transformative tool in head and neck surgery, with applications spanning oncologic insights and functional evaluations. This study delves into CLE's potential in these domains. (2) Methods: We performed CLE in head and neck oncologic surgery, focusing on tumor margin identification and precise resection. We also employed CLE for functional assessment in allergic rhinitis, observing real-time mucosal changes during nasal provocation testing. (3) Results: In oncologic surgery, CLE enabled real-time visualization of tumor margins and cellular patterns, aiding resection decisions. In allergic rhinitis assessment, CLE captured dynamic morphological alterations upon allergen exposure, enhancing understanding of mucosal reactions. (4) Conclusions: The integration of CLE with evolving technologies such as deep learning and AI holds promise for enhanced diagnostic accuracy. This study underscores CLE's expansive potential, highlighting its role in guiding surgical choices and illuminating inflammatory processes in the head and neck.

Intestinal barrier functions in hematologic and oncologic diseases

The intestinal barrier is a complex structure that not only regulates the influx of luminal contents into the systemic circulation but is also involved in immune, microbial, and metabolic homeostasis. Evidence implicating disruption in intestinal barrier functions in the development of many systemic diseases, ranging from non-alcoholic steatohepatitis to autism, or systemic complications of intestinal disorders has increased rapidly in recent years, raising the possibility of the intestinal barrier as a potential target for therapeutic intervention to alter the course and mitigate the complications associated with these diseases. In addition to the disease process being associated with a breach in the intestinal barrier functions, patients with hematologic and oncologic diseases are particularly at high risks for the development of increased intestinal permeability, due to the frequent use of broad-spectrum antibiotics and chemoradiation. They also face a distinct challenge of being intermittently severely neutropenic due to treatment of the underlying conditions. In this review, we will discuss how hematologic and oncologic diseases are associated with disruption in the intestinal barrier and highlight the complications associated with an increase in the intestinal permeability. We will explore methods to modulate the complication. To provide a background for our discussion, we will first examine the structure and appraise the methods of evaluation of the intestinal barrier.

The Role of Intestinal Permeability in Gastrointestinal Disorders and Current Methods of Evaluation

An increased intestinal permeability has been described in various gastrointestinal and non-gastrointestinal disorders. Nevertheless, the concept and definition of intestinal permeability is relatively broad and includes not only an altered paracellular route, regulated by tight junction proteins, but also the transcellular route involving membrane transporters and channels, and endocytic mechanisms. Paracellular intestinal permeability can be assessed in vivo by using different molecules (e.g., sugars, polyethylene glycols, ⁵¹Cr-EDTA) and ex vivo in Ussing chambers combining electrophysiology and probes of different molecular sizes. The latter is still the gold standard technique for assessing the epithelial barrier function, whereas in vivo techniques, including putative blood biomarkers such as intestinal fatty acid-binding protein and zonulin, are broadly used despite limitations. In the second part of the review, the current evidence of the role of impaired barrier function in the pathophysiology of selected gastrointestinal and liver diseases is discussed. Celiac disease is one of the conditions with the best evidence for impaired barrier function playing a crucial role with zonulin as its proposed regulator. Increased permeability is clearly present in inflammatory bowel disease, but the question of whether this is a primary event or a consequence of inflammation remains unsolved. The gut-liver axis with a crucial role in impaired intestinal barrier function is increasingly recognized in chronic alcoholic and metabolic liver disease. Finally, the current evidence does not support an important role for increased permeability in bile acid diarrhea.