Multi-scale Features Fusion for the Detection of Tiny Bleeding in Wireless Capsule Endoscopy Images

Wireless capsule endoscopy is a modern non-invasive Internet of Medical Imaging Things that has been increasingly used in gastrointestinal tract examination. With about one gigabyte image data generated for a patient in each examination, automatic lesion detection is highly desirable to improve the efficiency of the diagnosis process and mitigate human errors. Despite many approaches for lesion detection have been proposed, they mainly focus on large lesions and are not directly applicable to tiny lesions due to the limitations of feature representation. As bleeding lesions are a common symptom in most serious gastrointestinal diseases, detecting tiny bleeding lesions is extremely important for early diagnosis of those diseases, which is highly relevant to the survival, treatment, and expenses of patients. In this article, a method is proposed to extract and fuse multi-scale deep features for detecting and locating both large and tiny lesions. A feature extracting network is first used as our backbone network to extract the basic features from wireless capsule endoscopy images, and then at each layer multiple regions could be identified as potential lesions. As a result, the features maps of those potential lesions are obtained at each level and fused in a top-down manner to the fully connected layer for producing final detection results. Our proposed method has been evaluated on a clinical dataset that contains 20,000 wireless capsule endoscopy images with clinical annotation. Experimental results demonstrate that our method can achieve 98.9% prediction accuracy and 93.5% score, which has a significant performance improvement of up to 31.69% and 22.12% in terms of recall rate and score, respectively, when compared to the state-of-the-art approaches for both large and tiny bleeding lesions. Moreover, our model also has the highest AP and the best medical diagnosis performance compared to state-of-the-art multi-scale models.

Problems faced by patients and health service utilization experiences of gastrointestinal patients during lockdown due to COVID-19 pandemic

Objectives: The COVID-19 pandemic undermined the health service delivery and utilization of essential health care services globally. The current study therefore aimed to explore the health-seeking behaviors and challenges faced by patients for the management of gastrointestinal diseases. Methods: A cross-sectional study was conducted at the outpatient department of Gastroenterology, Liaquat National Hospital, Karachi from March 2020 to July 2020 during the COVID-19 lockdown phase to explore patient experiences. Data was collected using a survey questionnaire. All patients of either gender were included after informed consent. Statistical analysis of the data was conducted using SPSS 21.0. Results: A total of 184 patients were included who visited the hospital to seek medical services during the COVID-19 lockdown phase. The mean age of the population was 42.7 years (±16.13). Of these, n=94 (51.1%) were males All patients had gastrointestinal issues with different comorbid conditions. One forty-seven n=147 (79.9%) presented with active complaints whereas, n=37 (20.1%) patients visited the hospital for their follow-up checkup. Out of 184 patients, n=33 (17.9%) patients reported of having fear of visiting hospital due to COVID-19 outbreak. A statistically significant difference p<0.001 was noted between the history of comorbidities and patient delaying a visit to the healthcare due to the fear of COVID-19. Additionally, 61 (73.5%) patients with co-morbidity faced difficulty in finding public transport (p=0.01). Nevertheless, n=171 (93.0%) patients expressed satisfaction with the services provided by the hospital during the lockdown phase. Conclusion: Patients with gastrointestinal conditions were largely affected by lockdown largely due to fear of contacting COVID-19 disease and inaccessibility to the public transportation. Widely available telemedicine service might overcome these shortcomings and ensure continuity of quality care. doi: https://doi.org/10.12669/pjms.38.3.4799 How to cite this:Kalwar HA, Kamani L. Problems faced by patients and health service utilization experiences of gastrointestinal patients during lockdown due to COVID-19 pandemic. Pak J Med Sci. 2022;38(3):---------. doi: https://doi.org/10.12669/pjms.38.3.4799 This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Sex differences in pain-related behaviors and clinical progression of disease in mouse models of visceral pain

Previous studies have reported sex differences in irritable bowel syndrome (IBS) and inflammatory bowel disease (IBD) patients, including differences in visceral pain perception. Despite this, sex differences in behavioral manifestations of visceral pain and underlying pathology of the gastrointestinal tract have been largely understudied in preclinical research. In this study, we evaluated potential sex differences in spontaneous visceral nociceptive responses, referred abdominal hypersensitivity, disease progression and bowel pathology in mouse models of acute and persistent colon inflammation. Our experiments show that females exhibit more visceral nociceptive responses and referred abdominal hypersensitivity than males in the context of acute but not persistent colon inflammation. We further demonstrate that, following acute and persistent colon inflammation, visceral pain-related behavioral responses in females and males are distinct, with increases in licking of the abdomen only observed in females and increases in abdominal contractions only seen in males. During persistent colon inflammation, males exhibit worse disease progression than females, which is manifested as worse physical appearance and higher weight loss. However, no measurable sex differences were observed in persistent inflammation-induced bowel pathology, stool consistency or fecal blood. Overall, our findings demonstrate that visceral pain-related behaviors and disease progression in the context of acute and persistent colon inflammation are sex-dependent, highlighting the importance of considering sex as a biological variable in future mechanistic studies of visceral pain as well as in the development of diagnostics and therapeutic options for chronic gastrointestinal diseases.

Results of the non-interventional observational program: Influence of Novel COroNavirus on the condition of patients with liver and gastrointestinal Tract diseases and the effect of Ursodeoxycholic acid drugs and Rebamipide on the course of COVID-19 infection (CONTUR)

Intriduction. The course and outcome of COVID-19 infection in patients with liver and gastrointestinal tract diseases remain poorly understood. The article presents a multicenter non-interventional observational program conducted by the Russian Society for the Study of the Liver.Aim. To study the relationship between COVID-19 and injuries of gastrointestinal tract and liver, to assess the effect of therapy with UDCA and Rebamipide on the course and outcome of COVID-19 infection. Materials and methods. 460 patients were enrolled in the study, of which 46% were patients with gastrointestinal and liver diseases. Some patients received Rebamipide and UDCA at a dose of 15 mg/kg body weight, followed by assessment of the clinical and laboratory parameters.Results. In the study group, more severe lung injury and the course of infection were observed. The investigators detected three phenotypes of gastrointestinal tract injury: dyspeptic, diarrheal and painful. The latter was more common in patients with gastrointestinal diseases. Liver injury occurred in 87% of patients with COVID-19 (of which 44% had a history of liver disease). Increased ALT and AST were more often recorded in patients with obesity and diabetes mellitus and correlated with the severity of the infection. An inverse relationship was found between the albumin level and death and transfer to mechanical ventilation. At least 5-day Rebamipide therapy leads to reduction of diarrhea and abdominal pain (p < 0.00001 and p = 0.002), decrease in the levels of systemic inflammatory markers (CRP and ferritin, p<0.00001). The use of UDCA leads to a decrease of the systemic inflammation markers: ferritin and is associated with a significant decrease/normalization of ALT levels (p < 0.00001).Conclusions. In patients with diseases of the gastrointestinal tract and liver, COVID-19 develops in a more severe form and symptoms of gastrointestinal tract injury may prevail in the clinical picture. The severity of liver injury correlates with the severity of COVID-19 and a poor prognosis. Rebamipide reduces diarrhea and abdominal pain. UDCA prevents or reduces liver injury in COVID-19 infection. Both drugs reduce the level of systemic inflammation markers.

Vonoprozan: potentially new first-line treatment for delayed upper gastrointestinal bleeds following endoscopic procedures? A letter to the editor

Endoscopy nowadays is widely used as a diagnostic and therapeutic tool for various gastrointestinal diseases due to it being less invasive and safer. However, amongst some adverse events is delayed bleeding. The definition of delayed bleeding requires endoscopic hemostasis and/or blood transfusion after at least two days of treatment. (1) Oesophageal cancer is comparatively more common in Pakistan, being 7th most common malignancy in men and 6th most common in women in Karachi. (2) Oesophageal endoscopic submucosal dissection (E-ESD) employed in the treatment of the above- mentioned cancer has an incidence of delayed bleeding of about 1.3-6.7%. (1) The prevalence of gastric cancer across Pakistan was about 2-18% (3), for which endoscopic submucosal dissection is often used has an incidence of delayed bleeding of 4.7-15.6%. (1) Endoscopic therapy for gastroesophageal varices can also result in delayed bleeding, the incidence of which easily reaches up to 10%. (1) In a retrospective cohort study of 124,422 patients conducted in Japan, it was found that vonoprazan was more effective in reducing the risk of delayed bleeding compared to omeprazole. (OR= 0.75) (1) Vonoprazan works by competitively inhibiting the potassium-acid channel resulting in strong and sustained acid inhibition. (4) It was also found to have a superior effect in the eradication of H Pylori and an equal effect in acid-related disorders. (5) In the retrospective study mentioned above, it is also worth noting that the efficacy of vonoprazan was variable with respect to procedures and was most prominent with gastroduodenal endoscopic submucosal dissection (OR=0.70). (1) Other procedures did not elicit any significant difference. In addition, standard/high dose vonoprazan proved to be most efficacious in reducing the risk of delayed bleeding compared with standard/high-dose PPI and low-dose vonoprazan. It was also observed that patients taking anti-thrombotic medications at a higher risk of delayed bleeding also benefited from high-dose vonoprazan. (OR=0.74) (1) The findings above compel the conclusion that high dose vonoprazan should be ideal for reducing the risk of delayed bleeding in patients who have undergone gastroduodenal endoscopic submucosal dissection and/or are on anti-thrombotics. Though high-dose vonoprazan does look promising, it is imperative that more randomized controlled trials on more diverse populations be conducted to further explore its efficacy and safety as the drug might be a potential first line of therapy.

Bacterial Gut Microbiota and Infections During Early Childhood

Gut microbiota composition during the first years of life is variable, dynamic and influenced by both prenatal and postnatal factors, such as maternal antibiotics administered during labor, delivery mode, maternal diet, breastfeeding, and/or antibiotic consumption during infancy. Furthermore, the microbiota displays bidirectional interactions with infectious agents, either through direct microbiota-microorganism interactions or indirectly through various stimuli of the host immune system. Here we review these interactions during childhood until 5 years of life, focusing on bacterial microbiota, the most common gastrointestinal and respiratory infections and two well characterized gastrointestinal diseases related to dysbiosis (necrotizing enterocolitis and Clostridioides difficile infection). To date, most peer-reviewed studies on the bacterial microbiota in childhood have been cross-sectional and have reported patterns of gut dysbiosis during infections as compared to healthy controls; prospective studies suggest that most children progressively return to a “healthy microbiota status” following infection. Animal models and/or studies focusing on specific preventive and therapeutic interventions, such as probiotic administration and fecal transplantation, support the role of the bacterial gut microbiota in modulating both enteric and respiratory infections. A more in depth understanding of the mechanisms involved in the establishment and maintenance of the early bacterial microbiota, focusing on specific components of the microbiota-immunity-infectious agent axis is necessary in order to better define potential preventive or therapeutic tools against significant infections in children.

Expression of OLFM4 and Lysozyme During Necrotizing Enterocolitis and Volvulus in Newborns: a Comparative Observational Research Study

Background: In neonatal patients with necrotizing enterocolitis (NEC) and volvulus the inflammatory response is mediated by a plurality of different proteins. The proteins olfactomedin 4 (OLFM4) and lysozyme (LYZ) are part of the intestinal mucosal defense and especially OLFM4 has rarely been evaluated in neonatal gastrointestinal diseases. The aim of this study was to compare the expression levels of OLFM4 and lysozyme during NEC and volvulus in neonates. Methods: Intestinal tissues of patients with NEC and patients with volvulus were examined using immunohistochemical staining of OLFM4 and lysozyme of formalin-fixed and paraffin-embedded sections of resected tissue. Staining-positive tissues were semi-quantitatively scored from 0 (no staining), 1 (weak staining), 2 (moderate staining) to 3 (highly intense staining) by two individual investigators.Results: Both applied antibodies against OLFM4 showed different staining patterns with higher staining intensity of the antibody OLFM4 (D1E4M). OLFM4 (median score of the antibody OLFM4 (D1E4M): 3.0) and lysozyme (median score: 3.0) are highly expressed in intestinal and immune cells during NEC. The expression of OLFM4 and lysozyme in tissue with intestinal volvulus was also observable (median score of the antibody OLFM4 (D1E4M): 1.25) and median score of the antibody against LYZ: 2.0), but lower levels could be seen in comparison to tissue with NEC (p=0.033 and p=0.037, respectively).Conclusions: Both proteins, OLFM4 and lysozyme, may play a role in the pathogenesis of NEC and volvulus in neonatal patients, but the exact mechanisms of OLFM4 and lysozyme function and their role in immunological responses have not yet been resolved. These observations add new insights as basis for further large-scale population research.

Phages in the Gut Ecosystem

Phages, short for bacteriophages, are viruses that specifically infect bacteria and are the most abundant biological entities on earth found in every explored environment, from the deep sea to the Sahara Desert. Phages are abundant within the human biome and are gaining increasing recognition as potential modulators of the gut ecosystem. For example, they have been connected to gastrointestinal diseases and the treatment efficacy of Fecal Microbiota Transplant. The ability of phages to modulate the human gut microbiome has been attributed to the predation of bacteria or the promotion of bacterial survival by the transfer of genes that enhance bacterial fitness upon infection. In addition, phages have been shown to interact with the human immune system with variable outcomes. Despite the increasing evidence supporting the importance of phages in the gut ecosystem, the extent of their influence on the shape of the gut ecosystem is yet to be fully understood. Here, we discuss evidence for phage modulation of the gut microbiome, postulating that phages are pivotal contributors to the gut ecosystem dynamics. We therefore propose novel research questions to further elucidate the role(s) that they have within the human ecosystem and its impact on our health and well-being.