Diagnosis and classification of intestinal diseases with urine by surface-enhanced Raman spectroscopy

Intestinal Disease (ID) is often characterized by clinical symptoms such as malabsorption, intestinal dysfunction, and injury. If treatment is not timely, it will increase the risk of cancer. Early diagnosis of ID is the key to cure it. There are certain limitations of the conventional diagnostic methods, such as low sensitivity and specificity. Therefore, development of a highly sensitive, non-invasive diagnostic method for ID is extremely important. Urine samples are easier to collect and more sensitive to changes in biomolecules than other pathological diagnostic samples such as tissue and blood. In this paper, a diagnostic method of ID with urine by surface-enhanced Raman spectroscopy (SERS) is proposed. A classification model between ID patients and healthy controls (HC) and a classification model between different pathological types of ID (i.e., benign intestinal disease (BID) and colorectal cancer (CRC)) are established. Here, 830 urine samples, including 100 HC, 443 BID, and 287 CRC, were investigated by SERS. The ID/HC classification model was developed by analyzing the SERS spectra of 150 ID and 100 HC, while BID/CRC classification model was built with 300 BID and 150 CRC patients by principal component analysis (PCA)-support vector machines (SVM). The two established models were internally verified by leave-one-out-cross-validation (LOOCV). Finally, the BID/CRC classification model was further evaluated by 143 BID and 137 CRC patients as an external test set. It shows that the accuracy of the classification model validated by the LOOCV for ID/HC and BID/CRC is 86.4% and 85.56%, respectively. And the accuracy of the BID/CRC classification model with external test set is 82.14%. It shows that high accuracy can be achieved with these two established classification models. It indicates that ID patients in the general population can be identified and BID and CRC patients can be further classified with measuring urine by SERS. It shows that the proposed diagnostic method and established classification models provide valuable information for clinicians to early diagnose ID patients and analyze different stages of ID.

SLC26 Anion Transporters

Solute carrier family 26 (SLC26) is a family of functionally diverse anion transporters found in all kingdoms of life. Anions transported by SLC26 proteins include chloride, bicarbonate, and sulfate, but also small organic dicarboxylates such as fumarate and oxalate. The human genome encodes ten functional homologs, several of which are causally associated with severe human diseases, highlighting their physiological importance. Here, we review novel insights into the structure and function of SLC26 proteins and summarize the physiological relevance of human members.

Nanotechnology for research and treatment of the intestine

The establishment of intestinal in vitro models is crucial for elucidating intestinal cell-microbe intrinsic connections and interaction mechanisms to advance normalized intestinal diagnosis and precision therapy. This review discusses the application of nanomaterials in mucosal therapy and mechanism research in combination with the study of nanoscaffold in vitro models of the gut. By reviewing the original properties of nanomaterials synthesized by different physicochemical principles and modifying the original properties, the contribution of nanomaterials to solving the problems of short survival period, low cell differentiation rate, and poor reduction ability in traditional intestinal models is explored. According to nanomaterials’ different diagnostic mediators and therapeutic targets, the current diagnostic principles in inflammatory bowel disease, intestinal cancer, and other diseases are summarized inductively. In addition, the mechanism of action of nanomedicines in repairing mucosa, inhibiting inflammation, and alleviating the disease process is also discussed. Through such systematic elaboration, it offers a basis for nanomaterials to help advance in vitro research on the intestine and provide precision treatments in the clinic.

Detection and pathological role of intestinal protozoa in children

INTRODUCTION

Intestinal parasites are considered a growing public health problem, being protozoa the main cause of intestinal disease. The objective of our study is to compare the detection of intestinal protozoa by microscopy versus real-time PCR, as well as to determine the most prevalent protozoa in our environment in the paediatric population.

METHOD

An observational longitudinal study was carried out, both by microscopy and real time-PCR in stool samples from children (0-15 years) received from April 2019 to March 2021.Children were classified in two groups according if they had or not had clinical parasitosis. Microscopic examination was performed in all samples using the Ritchie concentration technique with the commercial Mini PARASEP system (Movaco-Grifols®). The presence of Cryptosporidium sp. was evaluated with the modified Ziehl-Neelsen acid-fast stain. The real-time PCR was performed to all samples using the Allplex ™ gastrointestinal parasite panel 4 (Seegene®).

RESULTS

During the study period, 500 samples were received, being positive 31 (6.2%) by microscopy and 256 (51.2%) by PCR. By microscopy, Blastocystis hominis was the most frequently observed (4.8%), followed by Giardia lamblia (1.6%), Dientamoeba fragilis (0.2%) and Cryptosporidium species (0.2%). Regarding the identification by PCR, D. fragilis (35.2%) was mainly identified, followed by B. hominis (28.1%), G. lamblia (7%) and Cryptosporidium sp. (0.8%) without finding clear differences in aetiology according to age. In the case of B. hominis and D. fragilis, there were not differences in the detection of these protozoa between the control group and children with clinical parasitosis (p = 0.11).

CONCLUSIONS

Real-time PCR increases the detection of intestinal protozoa, being underdiagnosed by microscopy, especially D. fragilis, in which PCR is considered the most appropriate method for its detection.

[Establishment of mini-guts organoid and research on intestinal disease from the new perspective]

Intestinal organoids, also named "mini-guts", reconstitute sophisticated three-dimensional architecture recapitulating diversified intestinal epithelial cell types and physiology, which is driven by the proliferative and self-assembling characteristics of crypt stem cells. The initiation of organoids study relies on the identification of Lgr5+ crypt stem cells from different intestinal segments and the key role of EGF, Wnt, BMP/TGF-β, Notch signal pathways within the microenvironment during the cultivation process. Besides constituting polarized crypt-villus structures, these "mini-guts" exhibit various effective functions of intestinal epithelium. Since 2009 when the culture system of small intestinal organoids was established by Sato et al, intestinal organoids excel conventional intestinal models depending on genetical mutation in multiple aspects and thus have become the hotspot among the research on intestinal diseases. Combined with genomics, material science and engineering, "mini-guts" have been widely applied to the research on intestinal development, intestinal transport physiology, epithelial barrier, pathogen-host interaction and the study on cystic fibrosis, infectious diarrhea, ulcerative colitis, Crohn's disease, intestinal cancer, etc. In this review, we summarize the new insights introduced by organoid into the research on intestinal diseases, and related research advances and applications.

Noninvasive early diagnosis of intestinal diseases based on artificial intelligence in genomics and microbiome

The maturing development in artificial intelligence (AI) and genomics has propelled the advances in intestinal diseases including intestinal cancer, inflammatory bowel disease (IBD), and irritable bowel syndrome (IBS). On the other hand, colorectal cancer is the second most deadly and the third most common type of cancer in the world according to GLOBOCAN 2020 data. The mechanisms behind IBD and IBS are still speculative. The conventional methods to identify colorectal cancer, IBD, and IBS are based on endoscopy or colonoscopy to identify lesions. However, it is invasive, demanding, and time-consuming for early-stage intestinal diseases. To address those problems, new strategies based on blood and/or human microbiome in gut, colon, or even feces were developed; those methods took advantage of high-throughput sequencing and machine learning approaches. In this review, we summarize the recent research and methods to diagnose intestinal diseases with machine learning technologies based on cell-free DNA and microbiome data generated by amplicon sequencing or whole-genome sequencing. Those methods play an important role in not only intestinal disease diagnosis but also therapy development in the near future.

Simultaneous quantification of enterotoxins tilimycin and tilivalline in biological matrices using HPLC high resolution ESMS2 based on isotopically 15N-labeled internal standards

Non-ribosomal peptides are one class of bacterial metabolites formed by gut microbiota. Intestinal resident Klebsiella oxytoca produces two pyrrolobenzodiazepines, tilivalline and tilimycin, via the same nonribosomal biosynthesis platform. These molecules cause human disease by genotoxic and tubulin inhibitory activities resulting in apoptosis of the intestinal epithelium, loss of barrier integrity and ultimately colitis. Here we report a fast, reliable, HPLC-HR-ESMS² method for quantifying simultaneously the bacterial enterotoxins tilimycin and tilivalline in complex biological matrices. We synthesized and applied stable isotopically labeled internal standards for precise quantification of the metabolites. Sample preparation was optimized using clinical and laboratory specimens including serum, colonic fluid and stool. The developed method overcame the disadvantage of low selectivity by applying high resolution mass spectrometry in MS² mode. High sensitivity and low interference from matrices were achieved and validated. We show that the approach is suitable for detection and quantification of the enterotoxic metabolites produced in vivo, in infected human or animal hosts, and in bacterial culture in vitro.

Integrated Phenotypic-Genotypic Analysis of Candidate Probiotic Weissella Cibaria Strains Isolated from Dairy Cows in Kuwait

Probiotics represent a possible strategy for controlling intestinal infections in livestock. Members of the Weissella genus are increasingly being studied for health-related applications in animals and humans. Here we investigated the functional properties of two Weissella cibaria strains isolated from cows reared in Kuwait breeding facilities by combining phenotypic with genomic analyses. W. cibaria SP7 and SP19 exhibited good growth in vitro under acidic conditions and in the presence of bile salts compared to the reference probiotic Lacticaseibacillus (formerly Lactobacillus) rhamnosus GG. Both strains were able to adhere to Caco-2 and HT-29 cell lines, as well as to mucin. The cell-free supernatants of the two isolates exhibited inhibitory activity towards Escherichia coli ATCC 25,922 and Salmonella enterica UC3605, which was ultimately due to the low pH of supernatants. W. cibaria SP19 showed a co-aggregation ability similar to that of L. rhamnosus GG when incubated with S. enterica. Whole genome sequencing and analysis revealed that both strains harbored several genes involved in carbohydrate metabolism and general stress responses, indicating bacterial adaptation to the gastrointestinal environment. We also detected genes involved in the adhesion to host epithelial cells or extracellular matrix. No evidence of acquired antibiotic resistance or hemolytic activity was found in either strain. These findings shed light on the potential of W. cibaria for probiotic use in livestock and on the mechanisms underlying host-microbe interaction in the gut. W. cibaria` strain SP19 exhibited the best combination of in vitro probiotic properties and genetic markers, and is a promising candidate for further investigation.

Increasing of SIgA serum levels may reflect subclinical intestinal involvement in non-radiographic axial and peripheral spondyloarthritis

OBJECTIVE

The evidence shows that previous infection with enteric pathogens is a requirement to develop pSpA. Based on our previous results, variances on regulation of SIgA might influence SpA activity; thus, the aim of this study was to correlate the levels of SIgA, IgA against some enteric bacteria, and IL-17, IL-21, and IL-6 with clinical features in a group of SpA patients.

METHODS

Twenty-six pSpA, 20 nr-axSpA, 60 healthy volunteers (HV), and 34 patients with inflammatory bowel diseases (IBD) were included. All subjects were assessed to measure SIgA, total and specific IgA for enteric bacteria, and IL-17, IL-21, and IL-6 levels and clinical variables. For SpA patients, the diagnosis was verified 5 years after first evaluation to assess the risk of developing r-axSpA.

RESULTS

SIgA levels were significantly higher in SpA patients than in HV and IBD (p < 0.0001 and p = 0.047, respectively). However, no differences for SIgA neither total IgA were found among the SpA subtypes (p = 0.624). Only IL-6 was higher in SpA than HV (p = 0.013). An inverse correlation was demonstrated for SIgA and BASFI (r: - 0.45; p = 0.003), BASDAI (r: - 0.39; p = 0.0123), ASDAS-CRP (r: - 0.37; p = 0.014), and ASDAS-ESR (r: - 0.45; p = 0.0021). There was no evidence of risk of developing r-axSpA in patients who previously showed high levels of serum antibodies.

CONCLUSION

The results show that pSpA as well as nr-axSpA share a similar SIgA-intestinal involvement independently of a previous infection. This suggests that serum SIgA increases are evidence of subclinical intestinal compromise which could have influence on disease activity but not in this progression. Key Point • The levels of SIgA, IgA against some enteric bacteria, and IL-17, IL-21, and IL-6 are correlated with clinical features in a group of SpA patients.

Soy Isoflavones and Gastrointestinal Health

PURPOSE OF REVIEW

Soy isoflavones are known to have beneficial effects on several aspects of gastrointestinal physiological functions (contractility or motility, secretion, morphology, and barrier function). In this review, we discuss the effects of soy isoflavones on the overall gut function and inflammation and assess how these effects might be implicated in the treatment of several gut-related diseases.

RECENT FINDINGS

Soy isoflavones influence several key aspects of gastrointestinal health: improve basal intestinal secretion, alleviate inflammation, limit intestinal morphological damage, and improve epithelial barrier function in several clinically relevant murine models of gastrointestinal diseases. Dietary supplementation with isoflavones proves to be a key means to improve the overall gut function and health. Future mechanistic studies with isoflavone interventions will help treat clinically related diseases such as cystic fibrosis and inflammatory-related gut problems such as colitis and diabetes.

Underlying mechanisms for intestinal diseases arising from stress

Stress is an instinctive defense mechanism of the body in the competition for survival, but long-term or chronic stress will lead to systemic pathological manifestations. Intestinal diseases are closely related to pathological stress. This paper reviews the pathogenesis of intestinal diseases arising from stress.

A case report of iatrogenic gas gangrene post colonoscopy successfully treated with conservative management- is surgery always necessary?

Background

Colonoscopy is a routine procedure in diagnosis and treatment of colonic disease. While generally regarded as a safe procedure, potentially fatal complications can occur. Gas gangrene is one such complication, with very high mortality. There are few cases of gas gangrene occurring after colonoscopy, making it one of the rarer complications of this procedure. There have been no previously reported cases of a patient surviving such an infection and the optimal treatment strategy is contentious. This report describes a case of intramural gas gangrene of the colon, treated conservatively with antibiotic therapy in which the patient survived with full recovery.

Case presentation

A 71-year-old, previously healthy male presented 6 h post apparently uncomplicated colonoscopic polypectomy with rigors, nausea, vomiting and right upper quadrant pain. At presentation he was febrile at 40.1 °C but hemodynamically stable. Abdominal computed tomography revealed substantial colonic thickening and several focal intramural gas bubbles (pneumatosis intestinalis) surrounding the polypectomy site. Within 24 h post procedure he became hypotensive and was admitted to ICU in frank septic shock requiring inotropes, and with demonstrable septic myocardial depression. Bloods showed multi-organ derangement with leukocytosis, lactic acidosis, haemolytic anaemia and hyperbilirubinemia. A diagnosis of presumed Clostridial gas gangrene was made, and treatment was initiated with benzylpenicillin, clindamycin, metronidazole and vancomycin. After 4 days in ICU he was stepped down, and discharged after a further 10 days with no surgical or endoscopic interventions. At three-month review he reported being back to full health.

Conclusions

This case demonstrates that gas gangrene infection is a possible complication of colonoscopic polypectomy. This is a cause of rapid deterioration in post-colonoscopy patients and has been misdiagnosed as colonic perforation in previously reported cases of retroperitoneal gas gangrene. Such misdiagnosis delays antibiotic therapy, which likely plays a role in the high mortality of this condition. Early diagnosis and initiation of antibiotic therapy with benzylpenicillin and clindamycin as seen in this case is essential for patient survival. While surgery is typically performed, non-operative management of pneumatosis intestinalis, and potentially gas gangrene is becoming more common and was utilized effectively in this patient.

Gastrointestinal Manifestations and Complications of Primary Immunodeficiency Disorders

Gastrointestinal (GI) involvement can be the presenting disease manifestation in patients with primary immunodeficiency disorders (PIDs). Infections and noninfectious diarrhea are frequent manifestations; however, malignancy and inflammatory and autoimmune-related GI diseases are also described. GI symptoms and disease seen in association with PIDs can mimic other diseases but are often resistant to conventional treatments owing to alternate disease mechanisms. Despite the advances in treatments for these conditions, therapy for immunodeficiency-related GI disease is often empiric.

Presentation and outcomes among inflammatory bowel disease patients with concurrent pneumatosis intestinalis: a case series and systematic review

Background/Aims

Inflammatory bowel disease (IBD) involves chronic inflammation of the colon with ulcerative colitis (UC), and the colon and/or small intestine with Crohn’s disease (CD). Pneumatosis intestinalis (PI), characterized by compromise of the intestinal wall with gas-filled cysts, has rarely been reported with IBD. The presentation, best management and outcomes of PI with IBD are poorly defined.

Methods

We conducted a search for PI in all abdominal computed tomography (CT) reports at 2 large tertiary care hospitals from January 1, 2010 to December 31, 2017, cross referenced to ICD codes for IBD. CT and chart review was performed to confirm PI and IBD respectively. A systematic review excluding case reports was performed for PI with IBD for comparison.

Results

Of 5,990 patients with a CT abdomen report mentioning PI, we identified 11 cases of PI with IBD, 4 UC, 6 CD, and 1 indeterminate colitis. PI was limited to the small bowel in 5 patients, the right colon in 5, and small bowel and colonic in 1. All 3 mortalities had CD, small intestinal PI and portal/mesenteric venous gas. The systematic literature search identified 9 articles describing 58 patients with IBD and PI. These cases were mostly included in larger cohorts of PI patients without extractable data on presentation or outcomes in the IBD subpopulation.

Conclusions

Ours appears to be the first reporting of presentations and outcomes, outside of case reports, for those with PI and IBD. The high mortality for those with CD and PI of the small bowel appears to define a group requiring more than supportive medical care.

Enterochromaffin cells and gastrointestinal diseases

Enterochromaffin cells (ECs), known for their special histochemical characteristics, originate from enteroblasts. For their important role in physiological and pathophysiological conditions, ECs in the gut could synthesize and secrete about 95% of 5-hydroxytryptamine (5-HT) in the body, which is an important humoral factor. As a chemosensor, ECs can regulate nutrition absorption and satiety through the sensory neural pathways. In addition, ECs participate in immune regulation. What's more, ECs and 5-HT are closely related to many kinds of gastrointestinal diseases.

Correlation between capillary oxygen saturation and small intestinal wall thickness in the equine colic patient

The surgical evaluation of haemorrhagic infarcted intestine and the decision for or against bowel resection require a lot of experience and are subjective. The aim of this prospective, clinical study was to examine the correlation between oxygen saturation and small intestinal wall (IW) thickness, using two objective methods. In 22 colicky horses, the blood flow, oxygen saturation and relative amount of haemoglobin were measured intraoperatively via laser Doppler and white light spectroscopy (O2C, oxygen to see, LEA Medizintechnik) at six measuring points (MPs) in small and large intestines. Furthermore, the IW thickness was measured ultrasonographically. Nine of 22 horses had an increased small IW thickness greater than 4 mm (Freeman 2002, Scharner and others 2002, le Jeune and Whitcomb 2014) at measuring point 1 (MP1) (strangulated segment), four horses had a thickened bowel wall at measuring point 3 (MP3) (poststenotic) and one at measuring point 2 (MP2). The oxygen saturation was 0 at MP1 in six horses, at MP3 in two horses and at MP2 (prestenotic) in one. Oxygen saturation and small IW thickness were independent of each other at MP1 and MP2. At MP3, the two parameters were negatively correlated. In summary, it is not possible to draw conclusions about oxygen saturation based on IW thickness.

Intestinal anti-inflammatory activity of Ground Cherry (Physalis angulata L.) standardized CO2 phytopharmaceutical preparation

AIM

To investigate the effects of Ground Cherry (Physalis angulata L.) standardized supercritical CO₂ extract in trinitrobenzenesulphonic acid (TNBS) model of rat intestinal inflammation.

METHODS

The animals were divided into groups that received vehicle or P. angulata extract (PACO₂) orally at the doses 25, 50 and 100 mg/kg daily by 5 d before TNBS damage. Protective effects of PACO₂ were assessed by macroscopic analysis, biochemical determinations of the levels of myeloperoxidase (MPO), alkaline phosphatase (ALP), glutathione and cytokines (such as INF-γ, IL-1β, IL-6, IL-10 and TNF-α), gene expression evaluation (including Hsp70, heparanase, NF-κB, mitogen-activated protein kinases (Mapk) 1, 3, 6 and 9, and the mucins genes Muc 1, 2, 3 and 4) and histopathological studies using optical, and electronic (transmission and scanning) microscopy.

RESULTS

PACO₂ extract promoted a significant reduction in MPO and ALP activities, reducing oxidative stress and neutrophil infiltration. These effects were accompanied by significant reduction of colonic levels of IFN-γ and IL-6 and down-regulation of heparanase, Hsp70, Mapk3, Mapk9, Muc1 and Muc2 genes expression when compared with TNBS-control animals. In addition, protective effects were also evidenced by reduced neutrophil infiltration, recovery of cell architecture and replacement of mucin by histopathological and ultrastructural analysis.

CONCLUSION

Physalis angulata supercritical CO₂ extract is an intestinal anti-inflammatory product that modulates oxidative stress, immune response and expression of inflammatory mediators, with potentially utility for treating inflammatory bowel disease.

Roles of amino acids in preventing and treating intestinal diseases: recent studies with pig models

Animal models are needed to study and understand a human complex disease. Because of their similarities in anatomy, structure, physiology, and pathophysiology, the pig has proven its usefulness in studying human gastrointestinal diseases, such as inflammatory bowel disease, ischemia/reperfusion injury, diarrhea, and cancer. To understand the pathogenesis of these diseases, a number of experimental models generated in pigs are available, for example, through surgical manipulation, chemical induction, microbial infection, and genetic engineering. Our interests have been using amino acids as therapeutics in pig and human disease models. Amino acids not only play an important role in protein biosynthesis, but also exert significant physiological effects in regulating immunity, anti-oxidation, redox regulation, energy metabolism, signal transduction, and animal behavior. Recent studies in pigs have shown that specific dietary amino acids can improve intestinal integrity and function under normal and pathological conditions that protect the host from different diseases. In this review, we summarize several pig models in intestinal diseases and how amino acids can be used as therapeutics in treating pig and human diseases.

Advances in understanding relationship between Faecalibacterium prausnitzii and intestinal disease

Recently, the relationship between intestinal dysbacteriosis and intestinal disease has become a hot research topic. As one of the most abundant symbiotic bacteria in the human gut, Faecalibacterium prausnitzii plays an important role in intestinal disease and has received more and more attention. This article reviews the advances in the understanding of the mechanism of action and active ingredients of this bacterium as well as its relationship with intestinal disease.

The mucosal barrier at a glance

Mucosal barriers separate self from non-self and are essential for life. These barriers, which are the first line of defense against external pathogens, are formed by epithelial cells and the substances they secrete. Rather than an absolute barrier, epithelia at mucosal surfaces must allow selective paracellular flux that discriminates between solutes and water while preventing the passage of bacteria and toxins. In vertebrates, tight junctions seal the paracellular space; flux across the tight junction can occur through two distinct routes that differ in selectivity, capacity, molecular composition and regulation. Dysregulation of either pathway can accompany disease. A third, tight-junction-independent route that reflects epithelial damage can also contribute to barrier loss during disease. In this Cell Science at a Glance article and accompanying poster, we present current knowledge on the molecular components and pathways that establish this selectively permeable barrier and the interactions that lead to barrier dysfunction during disease.

Claudin-related intestinal diseases. Semin Cell Dev Biol. 2015;42:30-38. [PMID: 25999319 DOI: 10.1016/j.semcdb.2015.05.006]

With up to 200 m(2) the human intestine is the organ with the largest absorptive surface of the body. It is lined by a single layer of epithelial cells that separates the host from the environment. The intestinal epithelium provides both, selective absorption of nutrients, ions, and water but also a highly effective barrier function which includes the first line of defense against environmental antigens. The paracellular part of this barrier function is provided by tight junction (TJ) proteins, especially the large family of claudins. Changes in abundance or molecular structure of claudins can generally result in three typical effects, (i) decreased absorptive passage, (ii) increased secretory passage of small solutes and water causing leak flux diarrhea and (iii) increased absorptive passage of macromolecules which may induce inflammatory processes. Several intestinal diseases are associated with such changes that can result in intestinal inflammation and symptoms like weight loss, abdominal pain or diarrhea. This review summarizes our current knowledge on barrier dysfunction and claudin dysregulation in several intestinal diseases gastroenterologists are often faced with, like inflammatory bowel disease, microscopic colitis, celiac disease, irritable bowel syndrome, gallstones and infectious diseases like HIV enteropathy, Campylobacter jejuni and Clostridium perfringens infection.

Prospective study of bacteraemia in acute haemorrhagic diarrhoea syndrome in dogs

In dogs with idiopathic acute haemorrhagic diarrhoea syndrome (AHDS), a serious loss of intestinal mucosal barrier integrity occurs. However, the incidence of bacterial translocation in dogs with idiopathic AHDS is not known. Thus, the objectives of this prospective study were to identify the incidence of bacteraemia, to evaluate the frequency of septic events and the influence of bacteraemia on various clinical and laboratory parameters, duration of hospitalisation and survival of dogs with idiopathic AHDS. The study included 87 dogs with idiopathic AHDS. Twenty-one healthy dogs served as control group. To evaluate clinical significance of bacterial translocation, blood culture results were compared between patients and controls. Clinical and laboratory parameters were compared between patients with positive and negative blood cultures. There was no significant difference in either incidence of bacteraemia between patients with idiopathic AHDS (11 per cent) and controls (14 per cent) or in severity of clinical signs, laboratory parameters, duration of hospitalisation or mortality between blood culture-positive and culture-negative dogs with idiopathic AHDS. The results of this study suggest that the incidence of bacteraemia in dogs with idiopathic AHDS is low and not different from that of healthy control dogs. Bacteraemia does not influence the clinical course or survival and thus antibiotic treatment is not indicated to prevent sepsis.

Detection of cytomegalovirus (CMV) by real-time PCR in fecal samples for the non-invasive diagnosis of CMV intestinal disease

BACKGROUND

Cytomegalovirus (CMV) infection of the gastrointestinal tract can cause CMV intestinal disease (CMV-ID), a severe complication in immunocompromised patients. Current gold standard for diagnosing CMV-ID requires the analysis of colon biopsies. Testing of fecal samples by CMV PCR might be a non-invasive diagnostic alternative, but data on this method is scarce.

OBJECTIVES

To evaluate the use of quantitative CMV real-time PCR in fecal samples for diagnosing CMV-ID.

STUDY DESIGN

Fecal samples and lower intestinal tract biopsies from 66 patients were analyzed by quantitative CMV PCR. To evaluate the diagnostic significance of CMV detection by PCR in fecal samples, patients were classified according to the etiology of their intestinal disease (based on results of endoscopy, histopathology and quantitative CMV DNA detection in biopsies) into three groups: "CMV-ID", "non-CMV-ID", and "equivocal".

RESULTS

10/66 fecal samples were tested positive by quantitative CMV PCR, but CMV DNA loads were low (range <1000-11,000copies/ml). CMV detection by PCR in fecal samples was positive in 8/12 patients of the CMV-ID group, resulting in a sensitivity of 67% for diagnosing CMV-ID. With two exceptions, fecal CMV PCR was negative in the non-CMV-ID group (45/47) indicating a good specificity (96%). Moreover, CMV DNA detection in feces was associated with high CMV DNA levels in intestinal biopsies.

CONCLUSIONS

Negative CMV PCR results from fecal samples cannot exclude CMV-ID and thus have to be confirmed by analyzing intestinal biopsies. However, positive fecal PCR results are diagnostically useful and might help to circumvent invasive diagnostic procedures as endoscopy.

Single balloon enteroscopy for diagnosis and treatment of small intestinal diseases

AIM: To evaluate the value of single balloon enteroscopy (SBE) in the diagnosis and treatment of small intestinal diseases.

METHODS: A total of 406 patients (255 males and 151 females) with suspected or confirmed small intestinal diseases underwent 629 SBE examinations (356 via the oral approach and 273 via the anal approach). A total of 292 cases (139 patients) underwent endoscopic therapy.

RESULTS: Of all the 406 cases, 300 were diagnosed with small intestinal diseases, and the diagnostic yield was 73.9% (300/406). The procedure time was 54.18 min ± 11.870 min for the oral approach, and 64.53 min ± 11.821 min for the anal approach. The intubation depth was 236.47 cm ± 90.397 cm for the oral approach, and 184.18 cm ± 65.716 cm for the anal approach. The main lesions were Peutz-Jeghers syndrome (119 cases), small intestinal inflammatory changes (45 cases), small intestinal ulcer (23 cases), Crohn's disease (23 cases), carcinoma of the small intestine (17 cases), small intestinal stromal tumors (15 cases), small bowel polyps (13 cases), and Meckel's diverticulum (10 cases). A total of 139 patients underwent 292 endoscopic therapies, of whom 112 underwent the resection of polyps, 9 underwent endoscopic hemostatic therapy, 16 underwent small intestinal stent implantation, and 2 underwent foreign body removal.

CONCLUSION: SBE has a high diagnostic yield in small intestinal diseases and can be used therapeutically, representing a safe and reliable method for diagnosis and treatment of intestinal diseases.

Role of Toll-like receptors in health and diseases of gastrointestinal tract

The human gastrointestinal (GI) tract is colonized by non-pathogenic commensal microflora and frequently exposed to many pathogenic organisms. For the maintenance of GI homeostasis, the host must discriminate between pathogenic and non-pathogenic organisms and initiate effective and appropriate immune and inflammatory responses. Mammalian toll-like receptors (TLRs) are members of the pattern-recognition receptor (PRR) family that plays a central role in the initiation of innate cellular immune responses and the subsequent adaptive immune responses to microbial pathogens. Recent studies have shown that gastrointestinal epithelial cells express almost all TLR subtypes characterized to date and that the expression and activation of TLRs in the GI tract are tightly and coordinately regulated. This review summarizes the current understanding of the crucial dual roles of TLRs in the development of host innate and adaptive immune responses to GI infections and the maintenance of the immune tolerance to commensal bacteria through down-regulation of surface expression of TLRs in intestinal epithelial cells.