Search

Introduction: Lower gastrointestinal bleeding (LGIB) frequently leads to emergency department (ED) visits and hospitalizations, encompassing a spectrum of outcomes from spontaneous resolution to intrahospital mortality. Aim: The purpose of this study was to validate a scoring system designed to identify cases of low-risk LGIB, allowing for safe discharge from the ED. Methods: A retrospective analysis of all gastrointestinal bleeding cases presented at three EDs in 2020 was conducted, focusing specifically on patients with LGIB. The SHA 2 PE score incorporates factors such as systolic blood pressure, hemoglobin levels, use of antiplatelet or anticoagulant medications, pulse rate, and episodes of bright blood per rectum. Results: Out of 1112 patients presenting with LGIB to the ED, 55 were hospitalized, 20 required blood transfusions, 15 underwent colonoscopies, one underwent interventional radiology procedures, and two patients died. Employing a SHA 2 PE score with a cutoff value of 1 yielded a specificity of 78.5% (95% CI (confidence interval) [75.8-81.0]), sensitivity of 76.8% (95% CI [63.6-87.0]), positive predictive value (PPV) of 17.0% (95% CI [12.6-22.2]), and negative predictive value (NPV) of 98.3% (95% CI [97.2-99.1]) for predicting the need for hospitalization and intrahospital intervention. When considering return visits to the ED within 7 days with the same presentation, the score demonstrated a specificity of 78.8% (95% CI [76.0-81.3]), sensitivity of 68.6% (95% CI [56.4-79.1]), PPV of 19% (95% CI [14.3-24.4]), and NPV of 97.2% (95% CI [95.8-98.2]). Conclusions: The SHA 2 PE score demonstrates potential in predicting cases of low-risk LGIB, offering a high NPV for hospitalization, the need for intrahospital intervention, and return visits to the ED. However, these findings should be interpreted cautiously given the low prevalence of interventions and limitations in the study's population and design., Competing Interests: The authors declare no conflicts of interest., (Copyright © 2025 Akram I. Ahmad et al. Gastroenterology Research and Practice published by John Wiley & Sons Ltd.)

The inability to discriminate between threat and safety is a hallmark of stress-induced psychiatric disorders, including post-traumatic stress disorder. Dorsolateral bed nucleus of the stria terminalis (BNST dl ) is critically involved in the modulation of fear and anxiety, and has been proposed to regulate discrimination between signaled (cued, predictable) and unsignaled (unpredictable) threats. We recently showed that oxytocin receptors (OTRs) in the BNST dl facilitate acquisition of cued fear measured in a fear-potentiated startle (FPS). In the current study, using in vivo microdialysis in awake male Sprague-Dawley rats, a double immunofluorescence approach with confocal microscopy, as well as retrograde tracing of hypothalamic BNST-projecting OT neurons, we investigated whether fear conditioning activates OT system and modulates OT release. To determine the role of OTR in fear memory formation, we also infused OTR antagonist or OT into the BNST dl before fear conditioning and measured rats' ability to discriminate between cued (signaled) and non-cued (unsignaled) fear using FPS. In contrast to acute stress (exposure to forced swim stress or foot shocks alone), cued fear conditioning increases OT content in BNST dl microdialysates. In addition, fear conditioning induces moderate activation of OT neurons in the paraventricular nucleus of the hypothalamus and robust activation in the supraoptic and accessory nuclei of the hypothalamus. Application of OT into the BNST dl facilitates fear learning toward signaled, predictable threats, whereas blocking OTR attenuates this effect. We conclude that OTR neurotransmission in the BNST dl plays a pivotal role in strengthening fear learning of temporally predictable, signaled threats.