The interactive role of mucosal T lymphocytes in intestinal growth, development and enteropathy

Abstract Over the past 15–20 years, research has progressively focused on the mucosal T cell as the central factor in the initiation of physiological or pathological changes, first in the growth and maturation of the early (postnatal) intestine, and second in adult-type enteropathies resulting from sensitivity to either food or pathogen-derived antigens. T cell-mediated events may be measured, for example, in terms of specific immunopathologic patterns of change and injury, such as type 1 (lymphocyte infiltration), type 2 (crypt hyperplasia) and type 3 (flat-destructive), which can be recognized and quantitated microscopically; by determination of lymphocyte reactivity through secretion of interleukin-2 receptors (IL-2R) into plasma or expression by mucosal lymphocytes; by quantitation of lymphocyte subsets emigrating into inflamed tissues by immunoperoxidase-labelled monoclonal antibodies; or by the determination of T cell receptor polymorphisms. Alterations in intestinal growth, structure and function at weaning are likely to be T cell-mediated as they are analogous to the same type 1/2 lesions that reflect modulation of adult mucosal architecture in food and parasite-induced hypersensitivity reactions. Enteropathies associated with HIV infection and T cell deficiency display a milder degree of villous flattening and impaired crypt hyperplasia than that typical of gluten-sensitivity, suggesting a reversion to lesser degrees of mucosal pathology (type 1/2). Clearly more information will accrue; meanwhile the remarks in this brief survey should provide a firm basis whereby clinician and scientist can meet, and together recognize and further dissect the modulatory effect of T lymphocytes on mucosal structure and function.     

Genetic susceptibility to gluten sensitive enteropathy in Irish setter dogs is not linked to the major histocompatibility complex

Abstract: Gluten sensitive enteropathy (GSE) in Irish setter dogs has been proposed as an animal model for human celiac disease (CD), in which the major histocompatibility complex (MHC) class II alleles HLA DQAl*0501 and DQBl*0201 play an important role. To investigate whether an orthologous MHC class II region is involved in canine GSE, we undertook a linkage study in two large families of gluten sensitive Irish setter dogs. A total of 44 dogs in these pedigrees were genotyped for DQA1, DQB1 and C.2202 alleles, along with 30 unrelated healthy Irish setters. No genetic linkage between the DQ or C.2002 loci and GSE was detected. In contrast to CD, susceptibility to canine GSE does not appear to be determined by variation within the MHC class II gene cluster. Therefore, canine GSE may not be an appropriate model for CD, but nevertheless remains an important disease for advancing knowledge of pathological processes in the intestine.     

Use of HLA marker associations and HLA haplotype linkage to estimate disease risks in families with gluten-sensitive enteropathy

Based on a two-locus, double recessive model, we derive formulas for the risks that relatives of individuals with gluten-sensitive enteropathy (GSE) will also develop the disease. The calculations take advantage of: the linkage between the HLA locus and one of the two proposed GSE loci, and the preferential association of the HLA-DR3 and DR7 alleles with the GSE disease allele that occupies the HLA-linked locus. We use Bayes' rule to quantitate the strength of the association between the GSE disease allele and the HLA marker allele. This method predicts that siblings of the proband have an overall 10% risk for GSE, which is consistent with observed family data. This predicted risk rises to 30% when siblings are HLA-identical to the proband (also consistent with observed data) or when the sibling has the DR3 allele in the HLA haplotypes not shared with the proband. In those populations where DR7 also is associated with GSE, siblings of probands have a 10% predicted risk for GSE when only one HLA haplotype is shared with the proband and DR7 is included in the unshared haplotype. Other DR alleles are associated with much lower disease risks. By separating individuals into high and low risk groups, HLA typing identifies those individuals who would benefit from further diagnostic procedures. This general strategy should be applicable to other multilocus, marker-associated diseases.     

Pediatric intestinal transplantation

Advancements in donor management, organ preservation and operative techniques, as well as immunosuppressive therapies, have provided children with intestinal failure and its complications a chance not only for enteral autonomy but also long-term survival through intestinal transplantation (ITx). First described in the 1960’s, experience has grown in managing these complex patients both pre- and post-transplant. The goals of this review are to provide a brief history of intestinal transplantation and intestinal rehabilitation in pediatric patients, followed by focused discussions of the indications for ITx, induction and maintenance immunosuppression therapies, common post-operative complications, and outcomes/quality of life post-transplant.     

Clinical and Genetic Characteristics of Korean Patients Diagnosed with Chronic Enteropathy Associated with SLCO2A1 Gene: A KASID Multicenter Study

Background/AimsChronic enteropathy associated with SLCO2A1 gene (CEAS), an inherited disease characterized by nonspecific intestinal ulcers, has emerged in the Japanese population via loss-of-function mutations in the SLCO2A1 gene. We aimed to investigate the clinical and genetic characteristics of Korean patients diagnosed with CEAS.MethodsFrom July 2018 to July 2021, we performed Sanger sequencing of the SLCO2A1 gene in 46 patients with chronic intestinal ulcers. CEAS was confirmed based on known SLCO2A1 mutations. We summarized the clinical characteristics of patients with confirmed CEAS.ResultsFourteen out of 46 patients (30.4%) had genetically confirmed CEAS, and two SLCO2A1 variants were detected (splicing site variant c.940+1G>A and nonsense mutation [p.R603X] in SLCO2A1). Twelve patients (85.7%) were females and the median age at diagnosis of CEAS was 44.5 years. All patients presented with abdominal pain, and 13 patients (92.9%) presented with anemia (median hemoglobin, 9.6 g/dL). Ten patients (71.4%) had hypoalbuminemia (median, 2.7 g/dL). The most commonly involved site was the ileum (13/14, 92.9%). Manifestations of primary hypertrophic osteoarthropathy (PHO), such as digital clubbing, pachydermia, and periostosis were observed in five patients (28.6%) and two male patients and one female patient satisfied all major PHO diagnostic criteria.ConclusionsThe clinical and genetic characteristics of Korean patients with confirmed CEAS were similar to those reported in the literature. CEAS should be considered in the differential diagnosis for patients with unexplained chronic nonspecific ulcers of the small intestine.     

Immune Dysregulation,Polyendocrinopathy, Enteropathy,X-linked Syndrome in Two Siblings: Same Mutation But Different Clinical Manifestations at Onset

Immune dysregulation, polyendocrinopathy, enteropathy, X-linked (IPEX) syndrome is an early onset systemic autoimmune genetic disorder caused by mutation of the forkhead box protein 3 (FOXP3) gene. Enteropathy, endocrinopathy and skin manifestations are considered the classic triad of IPEX syndrome. However, patients with IPEX syndrome display a variety of phenotypes including life threatening multi-organ autoimmunity. Here, we present the case of two siblings with IPEX syndrome with the same hemizygous mutation, but with different types of symptomology at onset of the disease.     

小儿肠衰竭治疗策略研究进展

小儿肠衰竭可致肠道消化、吸收、运动或分泌功能不足,不能满足儿童正常生长发育的需求,导致严重的水电解质失衡、营养不良等危及生命的临床后果.营养支持、并发症防治可大大地改善肠衰竭患儿的预后.文章综述了小儿肠衰竭的治疗进展.     

山药对糖尿病肠病患者血糖及胃肠激素的影响

目的探讨山药对糖尿病肠病患者空腹血糖、餐后2h血糖、空腹血清胰岛素、SP、VIP浓度变化的影响。方法将糖尿病肠病患者60人随机分为胰岛素组、胰岛素 山药组,观察两组干预前后空腹血糖、餐后血糖、空腹血清胰岛素的变化。以30名正常人、30名糖尿病肠病发作期患者为对照进行空腹血清SP,VIP浓度的检测。结果膳食摄入山药与胰岛素联合应用明显降低空腹血糖浓度、餐后2h血糖浓度,优于单纯胰岛素控制措施;糖尿病肠病患者血液SP浓度、VIP浓度,接近于正常水平。结论山药可调节糖尿病肠病患者血液SP浓度、VIP浓度,使之趋于正常水平,稳定糖尿病肠病患者血糖和改善肠道功能。     

Does the low FODMAP diet improve symptoms of radiation-induced enteropathy? A pilot study

Rationale: Patients with radiation-induced enteropathy (RE) after cancer treatment show similar symptoms as patients with irritable bowel syndrome (IBS). The low fermentable oligosaccharides, disaccharides, monosaccharides, and polyols (FODMAP) diet (LFD) is a widespread management strategy for IBS. We aimed to investigate if there may be a positive effect of LFD on symptoms and health-related quality of life (HRQOL) in patients with RE.

Methods: In an open non-controlled pilot study, 11 patients (all female) with RE-related IBS symptoms were recruited largely based on own initiative. All followed LFD for four weeks. IBS Severity Scoring System (IBS-SSS) and IBS Symptom Questionnaire (IBS-SQ) were used to assess symptoms. Short Form Nepean Dyspepsia Index (SF-NDI) and 12-item Short Form Health Survey (SF-12) evaluated HRQOL. A three day food record was used to estimate baseline intake of FODMAPs and to reveal dietary changes.

Results: FODMAP intake was successfully reduced, although LFD was found a burdensome intervention. IBS symptoms improved significantly based on mean total score of IBS-SSS and IBS-SQ, which changed from 310.2?±?60.7 to 171.4?±?107.2 (p?=?.001) and 27.4?±?4.1 to 15.7?±?10.1 (p?=?.002). HRQOL improved based on SF-NDI total score (30.5?±?9.4 to 18.3?±?8.2, p?=?.001) and based on mental (p?=?.047) and physical (p?=?.134) score of SF-12. Main additional dietary changes were reduced intake of energy, carbohydrates, and fiber.

Conclusion: Our findings from this small-scaled pilot study indicate that the LFD may alleviate symptoms and improve HRQOL in patients with RE. Further controlled studies with larger sample size should be conducted to verify our results and hopefully enable implementation of LFD as a future part of the management strategy for RE.     

Idiopathic Bile Acid Diarrhoea Reconsidered

Two new cases of a rare entity provisionally coined ‘idiopathic bile acid diarrhoea’ are reported and compared with previous cases. The diarrhoeal syndrome has been identified as a cholegenic enteropathy. In the absence of conventional ileopathy the cause of the bile acid loss is obscure, but it is hypothesized that it may be due to a relative deficiency in ileal absorptive sites for bile acid anions. So far the diagnosis has partly been based on measurements of faecal bile acid losses. It is suggested that a carefully conducted therapeutic trial with cholestyramine may be almost equally helpful.