Faecal Microbiome Transplantation as a Solution to Chronic Enteropathies in Dogs: A Case Study of Beneficial Microbial Evolution

Chronic enteropathies (CE) are gastrointestinal diseases that afflict about one in five dogs in Europe. Conventional therapeutic approaches include dietary intervention, pharmacological treatment and probiotic supplements. The patient response can be highly variable and the interventions are often not resolutive. Moreover, the therapeutic strategy is usually planned (and gradually corrected) based on the patient's response to empirical treatment, with few indirect gut health indicators useful to drive clinicians' decisions. The ever-diminishing cost of high-throughput sequencing (HTS) allows clinicians to directly follow and characterise the evolution of the whole gut microbial community in order to highlight possible weaknesses. In this framework, faecal microbiome transplantation (FMT) is emerging as a feasible solution to CE, based on the implant of a balanced, eubiotic microbial community from a healthy donor to a dysbiotic patient. In this study, we report the promising results of FMT carried out in a 9-year-old dog suffering from CE for the last 3 years. The patient underwent a two-cycle oral treatment of FMT and the microbiota evolution was monitored by 16S rRNA gene sequencing both prior to FMT and after the two administrations. We evaluated the variation of microbial composition by calculating three different alpha diversity indices and compared the patient and donor data to a healthy control population of 94 dogs. After FMT, the patient's microbiome and clinical parameters gradually shifted to values similar to those observed in healthy dogs. Symptoms disappeared during a follow-up period of six months after the second FMT. We believe that this study opens the door for potential applications of FMT in clinical veterinary practice and highlights the need to improve our knowledge on this relevant topic.

Modeling Enteropathy or Diarrhea with the Top Bacterial and Protozoal Pathogens: Differential Determinants of Outcomes

Developing effective therapeutics or preventive interventions for important health threats is greatly enhanced whenever accessible models can enable the assessment of clinically important outcomes. While no non-human model is ever perfect, inexpensive in vivo small animal models in such as mice are often of great help in assessing the relevant efficacy of potential interventions. In addition to acute diarrhea, the long-term growth and developmental effects of enteric infections, with or without overt diarrhea, are increasingly recognized. To address these diverse effects, inexpensive animal models are proving to be very helpful. Herein, we review the major clinical concerns with enteric parasitic and bacterial infections that are extremely common worldwide, especially in vulnerable young children living in impoverished areas, and the recently published murine models of these infections and their outcomes. We find that common dietary deficiencies seen in children in developing areas have striking effects on diarrhea and enteropathy outcomes in mice. However, these effects differ with different pathogens. Specifically, the effects of protein or zinc deficiency differ considerably with different major protozoal and bacterial pathogens, suggesting different pathogenetic pathways and intervention effects. The pathogens reviewed are the seven top parasitic and bacterial pathogens seen in children, namely, Cryptosporidium, Giardia, Campylobacter, Shigella, enterotoxigenic Escherichia coli (ETEC), enteroaggregative E. coli (EAEC), and enteropathogenic E. coli (EPEC).

Heterobilharzia americana infection in dogs: A retrospective study of 60 cases (2010-2019)

BACKGROUND

The trematode Heterobilharzia americana (HA) causes granulomatous gastrointestinal and hepatic disease in dogs. Before 2008, diagnosis relied on saline fecal sedimentation or histopathology, and earlier reports primarily described dogs with advanced disease or cases diagnosed incidentally at necropsy. The advent of a fecal PCR test has facilitated the diagnosis of HA and provided insights into manifestations and response to treatment.

OBJECTIVES

Describe the clinical findings, response to treatment, and outcome for dogs infected with HA.

ANIMALS

Sixty dogs diagnosed with HA between 2010 and 2019.

METHODS

Retrospective study. Medical records were searched for dogs diagnosed with HA by fecal PCR testing, identification of ova in feces, or histopathology.

RESULTS

Mean age was 7.5 (±4.1) years and weight was 23.2 (±10.18) kg. Clinical signs included diarrhea (55.8%), vomiting (46.2%), and weight loss with or without anorexia (15.4%). Laboratory abnormalities included hyperglobulinemia (42.6%) and increased liver enzyme activities (30%). More than 40% of dogs had an eosinophil count >500/μL. Hypercalcemia attributable to HA was identified in only 4 dogs. Pinpoint hyperechoic foci were noted in intestines, liver, or mesenteric lymph nodes during transabdominal ultrasonography in 64.4% of dogs. Survival data was available for 34 dogs, of which 73.5% (25) were alive 6 months after diagnosis.

CONCLUSIONS AND CLINICAL IMPORTANCE

Hyperglobulinemia, high eosinophil count, and ultrasonographic evidence of visceral mineralization were suggestive of infection. Hypercalcemia was uncommon. Combination treatment with praziquantel and fenbendazole was variably effective, and 17.6% of treated dogs with known outcome died as a result of HA infection.

Intestinal Fatty Acid Binding Protein Levels in Pediatric Celiac Patients in Transition From Active Disease to Clinical and Serological Remission

Celiac disease (CD) is increasingly diagnosed without endoscopy. As such, the need for accurate serological markers to aid in the diagnosis and follow-up of CD has increased. Intestinal fatty acid binding protein (I-FABP) is a cytosolic protein present in enterocytes, whose blood levels reflect mucosal damage in a reliable and quantifiable way. The aim of this study was to compare I-FABP levels in newly diagnosed patients with CD and to examine changes in levels following 6 months of gluten-free diet (GFD).

Methods

A prospective observational case control study of pediatric patients diagnosed with CD, with measurements of tissue transglutaminase IgA (TTG-IgA) and I-FABP levels at diagnosis and after 6 months of gluten free diet were compared to a control group of nonceliac patients.

Results

This study included 35 patients and 32 controls. The CD group had higher I-FABP levels at diagnosis compared with the control group (median 641.7 pg/mL versus 334 pg/mL; P < 0.05). I-FABP levels significantly differed between patients presenting with TTG-IgA level 3-10 times the upper limit of normal (ULN) compared with those presenting with values >10 times ULN (median 432.2 pg/mL versus 796.2 pg/mL; P < 0.05). Patients with CD had a significant decrease in median I-FABP levels after 6 months of GFD (median 268.2 pg/mL), paralleling a decrease in TTG-IgA and GFD adherence.

Conclusions

I-FABP levels are increased in patients with CD at diagnosis compared with controls and decrease significantly while patients adhere to GFD.

Characteristics of the intestinal microbiome in ankylosing spondylitis

The importance of intestinal microbiota in the development of various systemic diseases has been highlighted over time. Ankylosing spondylitis (AS) is a systemic disease with a complex pathogenesis involving a particular genetic marker and distinctive environmental triggers such as a specific gut dysbiosis. We conducted a prospective case-control study which included 60 subjects from Iasi Rehabilitation Hospital: 28 AS cases and 32 healthy controls. Intestinal microbiota analysis was performed by real-time polymerase chain reaction (qPCR) in stool samples. We performed the quantitative analysis of gut microbiome, focusing both on anti-inflammatory (Bifidobacterium, Lactobacillus, Faecalibacterium prausnitzii) and pro-inflammatory (Bacteroides, Escherichia coli) species. Overall, intestinal bacterial diversity in the AS group was decreased compared to that noted in the control. A significantly decreased level of Clostridium leptum was observed, associated with an increased level of Escherichia coli. We showed correlations between laboratory tests (liver and kidney functional tests, inflammatory syndrome), the presence of HLA-B27, smoker status, the forms of AS with peripheral arthritis vs. pure axial forms and bacterial structures. No significant correlations were shown for disease activity scores, radiological stage of sacroiliitis or for body mass index. Our findings support that the intestinal microbiome in AS patients has a special signature characterized by an inflammatory status. Numerous environmental, genetical, clinical and paraclinical factors can lead to changes in gut bacterial diversity in these cases.

A delayed diagnosis of atypical immune dysregulation, polyendocrinopathy, enteropathy, X-linked (IPEX) syndrome: A case report

INTRODUCTION

Immune dysregulation, polyendocrinopathy, enteropathy, and X-linked (IPEX) syndrome is a rare monogenic autoimmune disease, which is caused by mutations in the forkhead box protein 3 gene, can affect various systems. The typical clinical manifestations of IPEX are enteropathy, type 1 diabetes mellitus, and skin diseases. However, some atypical phenotypes can easily be misdiagnosed clinically.

PATIENT CONCERNS

A 9-year-and-7-month old patient suffered from recurrent wheezing, hematochezia, and eczematous dermatitis at the age of six months, but did not have any manifestations of autoimmune endocrinopathy. The patient was treated with glucocorticoids for more than six years, and he developed bronchiectasis.

DIAGNOSIS

Whole exome sequencing revealed a hemizygous pathogenic mutation c.1010G>A, p. (Arg337Gln) in Forkhead box protein 3 gene (NM_014009.3).

INTERVENTIONS

The patient was treated with oral mycophenolate mofetil combined with inhaled budesonide formoterol for six months after diagnosis.

OUTCOMES

The respiratory symptoms of the patient seemed to be controlled but eczematous dermatitis progressed, which led the patient to give up the treatment.

CONCLUSION

Early diagnosis and treatment of IPEX are crucial. Lung injury may be a major problem in the later stages of atypical IPEX, and mycophenolate mofetil seems to control the respiratory symptoms, but could induce significant skin side effects.

Coagulation status, fibrinolysis, and platelet dynamics in dogs with chronic inflammatory enteropathy

Background

Coagulation status is poorly understood in dogs with chronic inflammatory enteropathy (CIE). Fibrinolytic activity and platelet dynamics have not been evaluated in CIE dogs.

Objectives

To assess coagulation status and fibrinolysis in normoalbuminemic CIE dogs (CIE‐N) and CIE dogs with protein‐losing enteropathy (CIE‐PLE) compared to healthy controls (HC). To evaluate thromboelastography (TEG) variable differences between groups and for correlations with clinicopathologic data. To report platelet dynamics in CIE dogs.

Animals

Twenty‐five client‐owned dogs with CIE (n = 16 CIE‐N; n = 9 CIE‐PLE); 14 HC beagle dogs.

Methods

All dogs had tissue factor + tissue plasminogen activator TEG. Nine of 25 CIE dogs had whole blood impedance platelet aggregometry. The TEG variables and coagulation data were compared between all CIE vs HC dogs, CIE‐N dogs vs HC, and CIE‐PLE dogs vs HC. Clinicopathologic and coagulation data were available for CIE dogs and assessed for correlation to TEG variables.

Results

Dogs with CIE had higher maximum amplitude (MA; P < .001), longer clot lysis times (CLTs; P < .001), lower % lysis after 30 minutes (LY30; P < .001), and % lysis after 60 minutes (LY60; P < .001) compared to HC, suggesting hypercoagulability and hypofibrinolysis. When separated out, both CIE‐N and CIE‐PLE dogs had higher MA, longer CLT, and lower LY30 and LY60 compared to HC. Serum albumin and 25‐hydroxyvitamin D (25[OH]D) concentrations, and plasma antithrombin and fibrinogen concentrations moderately correlated with MA.

Conclusions and Clinical Importance

Normoalbuminemic and hypoalbuminemic CIE dogs were considered hypercoagulable based on TEG compared to HC. Some CIE dogs displayed hypofibrinolytic phenotypes on TEG.

Primary hypoparathyroidism in a patient with common variable immunodeficiency associated enteropathy

Background. Common variable immunodeficiency (CVID) is a rare disease characterized by humoral immunodeficiency, often causing sinopulmonary and gastrointestinal infections, and may cause enteropathy in some patients, which leads to severe malnutrition and electrolyte deficiencies. Although many autoimmune diseases are seen with increased frequency in CVID patients, primary hypoparathyroidism is extremely rare.Case presentation. A 50-year-old man with CVID presented with diarrhea. The patient had complaints for 2 years and was cachectic. He had severe electrolyte and vitamin deficiencies that did not respond to oral treatment. The diarrhea causes such as celiac, inflammatory bowel diseases, and gastrointestinal infections were excluded and the endoscopy showed enteropathic changes in the duodenum and colon. Concomitant hypoparathyroidism was also detected in the patient with hypocalcemia despite adequate replacement.Conclusion. Parenteral therapy should be considered in the management of CVID enteropathy cases that do not respond to oral replacement. Although very rare, hypoparathyroidism should be considered in the differential diagnosis of CVID patients with treatment-resistant hypocalcemia.

Serum haptoglobin concentrations in feline inflammatory bowel disease and small-cell alimentary lymphoma: a potential biomarker for feline chronic enteropathies

OBJECTIVES

The aim of this study was to evaluate serum haptoglobin as a biomarker to differentiate between small-cell alimentary lymphoma and inflammatory bowel disease in cats.

METHODS

Client-owned domestic cats with and without chronic gastrointestinal signs were enrolled in the study. Serum was collected from each patient and serum haptoglobin levels were measured using ELISA. In cats with gastrointestinal signs, histopathologic evaluation of endoscopic biopsies harvested from the intestinal tract was used to separate them into inflammatory bowel disease and small-cell lymphoma cohorts. Serum haptoglobin levels were statistically analyzed and compared among the three groups: healthy cats; cats with inflammatory bowel disease; and cats with small-cell alimentary lymphoma.

RESULTS

Sixty-two cats were enrolled in the study, including 20 clinically normal cats, 14 cats with small-cell alimentary lymphoma and 28 cats with inflammatory bowel disease. The mean ± SD serum haptoglobin was 73.2 ± 39.1 mg/dl in normal cats, 115.3 ± 72.8 mg/dl in cats with inflammatory bowel disease and 133.1 ± 86.1 mg/dl in cats with small-cell alimentary lymphoma. Cats with inflammatory bowel disease and lymphoma had significantly higher serum haptoglobin than controls, with P values of 0.0382 and 0.0138, respectively. There was no statistical difference between the inflammatory bowel disease and lymphoma cohorts (P = 0.4235). For every one unit increase in serum haptoglobin, the odds of gastrointestinal inflammatory disease (inflammatory bowel disease or small-cell alimentary lymphoma) increased by 1.41% (P = 0.0165).

CONCLUSIONS AND RELEVANCE

Serum haptoglobin is a useful biomarker for distinguishing between normal cats and those with gastrointestinal inflammatory disease, but it could not significantly differentiate between inflammatory bowel disease and lymphoma. Additional studies may be beneficial in determining the prognostic significance of serum haptoglobin as it may relate to the severity of gastrointestinal inflammation.

Congenital Diarrhea and Cholestatic Liver Disease: Phenotypic Spectrum Associated with MYO5B Mutations

Myosin Vb (MYO5B) is a motor protein that facilitates protein trafficking and recycling in polarized cells by RAB11- and RAB8-dependent mechanisms. Biallelic MYO5B mutations are identified in the majority of patients with microvillus inclusion disease (MVID). MVID is an intractable diarrhea of infantile onset with characteristic histopathologic findings that requires life-long parenteral nutrition or intestinal transplantation. A large number of such patients eventually develop cholestatic liver disease. Bi-allelic MYO5B mutations are also identified in a subset of patients with predominant early-onset cholestatic liver disease. We present here the compilation of 114 patients with disease-causing MYO5B genotypes, including 44 novel patients as well as 35 novel MYO5B mutations, and an analysis of MYO5B mutations with regard to functional consequences. Our data support the concept that (1) a complete lack of MYO5B protein or early MYO5B truncation causes predominant intestinal disease (MYO5B-MVID), (2) the expression of full-length mutant MYO5B proteins with residual function causes predominant cholestatic liver disease (MYO5B-PFIC), and (3) the expression of mutant MYO5B proteins without residual function causes both intestinal and hepatic disease (MYO5B-MIXED). Genotype-phenotype data are deposited in the existing open MYO5B database in order to improve disease diagnosis, prognosis, and genetic counseling.

The Prevalence of Enteropathy Symptoms from the Lower Gastrointestinal Tract and the Evaluation of Anorectal Function in Diabetes Mellitus Patients

Complications affecting the gastrointestinal tract often occur in the course of diabetes mellitus (DM). The aim of this study was to evaluate enteropathy symptoms and anorectal function using high-resolution anorectal manometry (HRAM). Fifty DM patients and 20 non-DM controls were enrolled into the study. Clinical data and laboratory tests were collected, physical examination and HRAM were performed. Symptoms in the lower gastrointestinal tract were reported by 72% of patients. DM patients with a long disease duration reported anal region discomfort (p = 0.028) and a sensation of incomplete evacuation (p = 0.036) more often than patients with shorter diabetes duration. Overall, DM patients had a lower maximal squeeze pressure (MSP) (p = 0.001) and a higher mean threshold of minimal rectal sensation (p < 0.01) than control subjects. They presented with enhanced features of dyssynergic defection than the control group. MSP and maximal resting pressure (MRP) were significantly lower in the group of long-term diabetes (p = 0.024; p = 0.026 respectively) than in patients with a short-term diabetes. The same observation was noted for patients with enteropathy symptoms that control for MSP (p < 0.01; p < 0.01; p = 0.03) and MRP (p < 0.001; p = 0.0036; p = 0.0046), respectively, for incontinence, constipation, and diarrhea. Symptoms in the lower gastrointestinal tract are often reported by DM patients. All DM patients have impaired function of the external anal sphincter and present enhanced features of dyssynergic defecation and also impaired visceral sensation. Patients with long-standing DM and patients with enteropathy symptoms have severely impaired function of both anal sphincters.

Portal hypertensive vasculopathy - An entity worth remembering with non-neoplastic gastrointestinal lesions

Portal hypertensive vasculopathy (PHV) represents an increase in the pressure in the portal circulation. This increased pressure leads to changes in the mucosa that can be appreciated endoscopically as well as histopathologically. Lesions can be observed in the entire gastrointestinal tract (GIT) including stomach, duodenum, jejunum and colon. The histological changes are appreciated mainly in the mucosal and submucosal blood vessels. A knowledge of these lesions as well as the changes helps in separating them from other close differentials with specific treatment to be instituted. The pathogenesis of the hemodynamic changes is not well-understood. The underlying factor is increased portal pressure. Studies indicate, that besides increased portal pressure other factors in combination led to the observed changes. Portal hypertensive gastropathy (PHG) is seen in the gastric body and fundus, while varices are noted in the cardia and fundus. Changes may be seen in the small intestine and throughout the colon with anorectal varices. Histopathological changes include dilated, congested and ectatic capillaries and edema in the lamina propria besides a large spectrum of other histopathological changes. Mucosal capillaries with thick irregular wall show absence of red blood cells in the lumen. Thickening of the vessel wall serves as a better marker than the vascular diameter when portal hypertension (PHT) is considered. Long standing cases may show fibrosis in lamina propria. At times, these changes may lead to occult gastrointestinal bleeding. Important differentials need to be ruled out in all the cases as the treatment and the outcome of all differs. Endoscopically or histopathologically if the mucosal changes are observed they should not be overlooked and a detailed work-up must be carried out.

Faecal calprotectin and gut microbiota do not predict enteropathy in very preterm infants

Aim

Very preterm birth is associated with a high risk of enteropathies. Diagnosis is challenging, especially in mild forms, leading to unnecessary periods of cessation of enteral feeding. This study aimed at establishing a prognosis score of enteropathy combining clinical parameters and faecal calprotectin concentration.

Methods

This prospective multicentric study included preterm neonates born at a gestational age of 33 weeks or less. Stools were collected weekly until hospital discharge, and daily in case of digestive events for calprotectin measurement (ELISA and immunochromatography) and microbiota analyses (16S rRNA gene sequencing).

Results

Among the 121 neonates included, 21 experienced at least one episode of enteropathy, mainly mild forms. By ELISA testing, median faecal calprotectin was 88 (8‐798) µg/g faeces. No statistically significant association was found between the outset of enteropathy and maternal and neonatal characteristics, and calprotectin levels. The agreement between ELISA and immunochromatography assay was moderate (intra‐class correlation coefficient 0.58, 95%CI [0.47‐0.66]). Comparison of species diversity and relative bacterial abundance profiles between infants with or without enteropathy revealed no specific alterations associated with enteropathy.

Conclusion

The study failed to propose a prognostic score of enteropathy, probably due the large inter‐ and intra‐individual variability of faecal calprotectin in very preterm neonates.

Leishmaniasis and Autoimmunity in Patient with LPS-Responsive Beige-Like Anchor Protein (LRBA) Deficiency

BACKGROUND/OBJECTIVE

LPS-responsive beige-like anchor protein (LRBA) deficiency is a combined immunodeficiency and immune dysregulation. The authors present a case report of LPSresponsive beige-like anchor protein (LRBA) deficiency with the history of autoimmunity, enteropathy and visceral leishmaniasis. Sirolimus therapy was started for autoimmunity and enteropathy but was discontinued due to recurrent leishmaniasis. Therefore, a common side-effect of many immunosuppressive drugs in patients with LRBA deficiency is increased susceptibility to infections.

METHODS

Whole exome sequencing was performed to detect the underlying genetic mutation and Leishmania DNA was detected by the PCR technique in this patient.

RESULTS

Whole exome sequencing of the patient reported a homozygous frameshift deletion mutation in the LRBA gene (NM_006726: exon29: c.4638delC, p. S1546fs). Leishmania DNA PCR was positive in this case.

CONCLUSION

Parasite infections manifestations report in LRBA deficiency. Leishmania infections in patients with chronic diarrhea and autoimmunity should be considered for immunodeficiency.

The role of histopathology in the diagnosis and management of coeliac disease and other malabsorptive conditions

Most absorption of nutrients takes place in the proximal small intestine, and the most common disorders leading to malabsorption are associated with a morphological abnormality in the duodenal mucosa that is appreciable in histological sections of biopsy specimens. Coeliac disease is the most well-known example, causing intraepithelial lymphocytosis, inflammation and villous atrophy in the duodenum. Remarkably similar inflammatory changes can be induced by other processes, including medications, e.g. angiotensin II receptor blockers and immune checkpoint inhibitors, immune dysregulation disorders, e.g. common variable immunodeficiency and autoimmune enteropathy, infections, collagenous sprue, and tropical sprue. However, there are often subtle histological differences from coeliac disease in the type of inflammatory infiltrate, the presence of crypt apoptosis, and the extent and type of inflammation beyond the duodenum. The clinical setting and serological investigation usually allow diagnostic separation, but some cases remain challenging. Histopathology is also important in assessing the response to treatment, such as the change in villous architecture caused by a gluten-free diet, or the response to cessation of a potentially causative medication. This review examines the practical role that histopathology of duodenal biopsy specimens plays in the assessment and management of inflammatory malabsorptive processes of the proximal small intestine, with a particular emphasis on coeliac disease.

Enteropathogenic Escherichia coli Infection Induces Diarrhea, Intestinal Damage, Metabolic Alterations, and Increased Intestinal Permeability in a Murine Model

Enteropathogenic E. coli (EPEC) are recognized as one of the leading bacterial causes of infantile diarrhea worldwide. Weaned C57BL/6 mice pretreated with antibiotics were challenged orally with wild-type EPEC or escN mutant (lacking type 3 secretion system) to determine colonization, inflammatory responses and clinical outcomes during infection. Antibiotic disruption of intestinal microbiota enabled efficient colonization by wild-type EPEC resulting in growth impairment and diarrhea. Increase in inflammatory biomarkers, chemokines, cellular recruitment and pro-inflammatory cytokines were observed in intestinal tissues. Metabolomic changes were also observed in EPEC infected mice with changes in tricarboxylic acid (TCA) cycle intermediates, increased creatine excretion and shifts in gut microbial metabolite levels. In addition, by 7 days after infection, although weights were recovering, EPEC-infected mice had increased intestinal permeability and decreased colonic claudin-1 levels. The escN mutant colonized the mice with no weight loss or increased inflammatory biomarkers, showing the importance of the T3SS in EPEC virulence in this model. In conclusion, a murine infection model treated with antibiotics has been developed to mimic clinical outcomes seen in children with EPEC infection and to examine potential roles of selected virulence traits. This model can help in further understanding mechanisms involved in the pathogenesis of EPEC infections and potential outcomes and thus assist in the development of potential preventive or therapeutic interventions.

Diagnostic Approach to the Patients with Suspected Primary Immunodeficiency

BACKGROUND AND OBJECTIVE

Primary immunodeficiency diseases (PIDs) are a group of more than 350 disorders affecting distinct components of the innate and adaptive immune systems. In this review, the classic and advanced stepwise approach towards the diagnosis of PIDs are simplified and explained in detail.

RESULTS

Susceptibility to recurrent infections is the main hallmark of almost all PIDs. However, noninfectious complications attributable to immune dysregulation presenting with lymphoproliferative and/or autoimmune disorders are not uncommon. Moreover, PIDs could be associated with misleading presentations including allergic manifestations, enteropathies, and malignancies.

CONCLUSION

Timely diagnosis is the most essential element in improving outcome and reducing the morbidity and mortality in PIDs. This wouldn't be possible unless the physicians keep the diagnosis of PID in mind and be sufficiently aware of the approach to these patients.

Evaluation of Expression of LRBA and CTLA-4 Proteins in Common Variable Immunodeficiency Patients

Common variable immunodeficiency (CVID) is a primary immunodeficiency disease with a heterogeneous genetic background. Lipopolysaccharide-responsive beige-like anchor (LRBA), as well as cytotoxic T-lymphocyte-associated protein 4 (CTLA-4), have important regulatory roles in the immune responses. Here, we have investigated the expression of LRBA and CTLA-4 proteins in CVID patients with at least one presentation of early-onset occurrence, autoimmunity, or enteropathy. In this study, 20 newly diagnosed CVID patients without infection only phenotype, and ten healthy individuals were enrolled. The expressions of LRBA and CTLA-4 proteins were assessed by western blotting and flow cytometry, respectively. The patients were divided into two groups of autoimmunity-positive (11 cases) and autoimmunity-negative (9 patients). LRBA and CTLA-4 expressions were significantly lower in autoimmune-positive patients than in healthy individuals (P = .03 and P = .03, respectively). Autoimmune-negative patients had lower expression of LRBA and CTLA-4 than the control group, although it was not significant. There was a positive correlation between the expressions of LRBA and CTLA-4 in both groups of patients (P < .05). Furthermore, the highest frequency of LRBA (85.7%) and CTLA-4 (71.4%) defects was detected in those with concomitant presence of autoimmunity, enteropathy, and early-onset occurrence. Concurrent presence of autoimmunity, enteropathy, and early-onset occurrence in CVID patients could be indicative of a lack of expression in LRBA and CTLA-4 proteins. This could be helpful in early diagnosis and initiation of appropriate treatment in these patients prior to genetic confirmation.

Ultrasonographic findings of gastrointestinal histoplasmosis in dogs

Histoplasmosis, a mycotic infection caused by Histoplasma spp, can infect the gastrointestinal tract of dogs. Clinical signs of gastrointestinal histoplasmosis can include diarrhea, profound weight loss, anorexia, and vomiting. Rectal scrape for cytology can provide a quick diagnosis, but if negative abdominal ultrasound is often pursued. Ultrasonographic abnormalities in dogs with gastrointestinal histoplasmosis have rarely been reported. This retrospective, single-center case series aimed to describe the ultrasonographic features of gastrointestinal histoplasmosis in dogs. Nineteen cases with a diagnosis of gastrointestinal histoplasmosis confirmed with gastrointestinal cytology or histopathology (N = 15) or gastrointestinal lymph node cytology (N = 4) that had undergone an abdominal ultrasound examination from 2005 to 2020 were included. Ultrasound images were reviewed by an American College of Veterinary Radiology (ACVR)-certified veterinary radiologist and diagnostic imaging resident. Eighteen cases had sonographic abnormalities within the gastrointestinal tract. The colon was the most affected organ. Colonic thickening and abnormal wall layering were the most frequent findings (N = 16 dogs); thickening ranged from 0.36 to 1.2 cm. Diffuse, multifocal, and focal thickening patterns were seen. Sixteen patients had abnormal wall layering of the colon (complete loss of layering or altered with partial loss of layering). Other frequent findings included lymphadenopathy, small intestinal thickening with abnormal wall layering and peritoneal effusion. Based on the authors' review of the literature, this is the first description of ultrasonographic findings of gastrointestinal histoplasmosis in a group of dogs. Although abnormal gastrointestinal wall layering seen sonographically is most frequently associated with neoplasia, this is not pathognomonic. Gastrointestinal histoplasmosis should be considered as a differential diagnosis due to the similarities and overlap of ultrasonographic features.

The Protective Effect of 5-Aminosalicylic Acid Against Non-Steroidal Anti-Inflammatory Drug-Induced Injury Through Free Radical Scavenging in Small Intestinal Epithelial Cells

Background and objectives: Non-steroidal anti-inflammatory drugs (NSAIDs) have been among the major causes of small intestinal injury in clinical practice. As such, the current study investigated the protective effect of 5-aminosalicylic acid (5-ASA) against an NSAID-induced small intestinal injury. Materials and Methods: IEC-6 cells were treated with various concentrations of indomethacin with or without 5-ASA in a serum-free medium, after which an 3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Dromide (MTT) assay, a cell apoptosis assay, a caspase-3 activity assay, a reactive oxygen species (ROS) content and Superoxide dismutase 2 (SOD2) activity measurement, a Western blotting for occludin and zonula occludens-1 (ZO-1) and a wound healing assay were conducted. Results: 5-ASA ameliorated indomethacin-induced cell apoptosis and an increase in the intracellular ROS content while augmenting the indomethacin-induced suppression of SOD2 activity in IEC-6 cells. Moreover, 5-ASA reversed the indomethacin-induced attenuation of occludin and ZO-1 expression and promoted faster wound healing effects in IEC-6 cells following an indomethacin-induced injury. Conclusions: Our results suggested that 5-ASA protects small intestinal cells against an NSAID-induced small intestinal injury by scavenging free radicals. Therefore, 5-ASA could be a potential treatment for an NSAID-induced small intestinal injury.

Monogenic Inflammatory Bowel Disease: It's Never Too Late to Make a Diagnosis

Background: More than 50 different monogenic disorders have been identified as directly causing inflammatory bowel diseases, typically manifesting in the first years of life. We present the clinical course and immunological work-up of an adult patient who presented in adolescent years with an atypical gastrointestinal phenotype and was diagnosed more than two decades later with a monogenic disorder with important therapeutic implications.

Methods: Whole exome sequencing was performed in a 37-years-old patient with a history of diarrhea since adolescence. Sanger sequencing was used to validate the suspected variant. Mass cytometry (CyTOF) and flow cytometry were conducted on peripheral blood mononuclear cells for deep immunophenotyping. Next-generation sequencing of the TCRB and IgH was performed for global immune repertoire analysis of circulating lymphocytes.

Results: We identified a novel deleterious c.1455C>A (p.Y485X) mutation in LRBA. CyTOF studies demonstrated significant changes in immune landscape in the LRBA-deficient patient, including an increase in myeloid derived suppressor cells and double-negative T cells, decreased B cells, low ratio of naïve:memory T cells, and reduced capacity of T cells to secrete various cytokines following stimulation, including tumor necrosis factor alpha (TNF-α) and interferon gamma (IFN-γ). In addition, this patient exhibited low frequency of regulatory T cells, with a reduction in their CTLA4 expression and interleukin (IL)-10 secretion. Finally, we show marked oligoclonal expansion of specific B- and T-cell clones in the peripheral blood of the LRBA-deficient patient.

Conclusions: LRBA deficiency is characterized by marked immunological changes in innate and adaptive immune cells. This case highlights the importance of advanced genetic studies in patients with a unique phenotype, regardless of their age at presentation.

Intervention and Mechanisms of Alanyl-glutamine for Inflammation, Nutrition, and Enteropathy: A Randomized Controlled Trial

OBJECTIVE

Determine the minimum dosage of alanyl-glutamine (Ala-Gln) required to improve gut integrity and growth in children at risk of environmental enteropathy (EE).

METHODS

This was a double-blinded randomized placebo-controlled dose-response trial. We enrolled 140 children residing in a low-income community in Fortaleza, Brazil. Participants were 2 to 60 months old and had weight-for-age (WAZ), height-for-age (HAZ), or weight-for-height (WHZ) z-scores less than -1. We randomized children to 10 days of nutritional supplementation: Ala-Gln at 3 g/day, Ala-Gln at 6 g/day, Ala-Gln at 12 g/day, or an isonitrogenous dose of glycine (Gly) placebo at 12.5 g/day. Our primary outcome was urinary lactulose-mannitol excretion testing. Secondary outcomes were anthropometry, fecal markers of inflammation, urine metabolic profiles, and malabsorption (spot fecal energy).

RESULTS

Of 140 children, 103 completed 120 days of follow-up (24% dropout). In the group receiving the highest dose of Ala-Gln, we detected a modest improvement in urinary lactulose excretion from 0.19% on day 1 to 0.17% on day 10 (P = 0.05). We observed significant but transient improvements in WHZ at day 10 in 2 Ala-Gln groups, and in WHZ and WAZ in all Ala-Gln groups at day 30. We detected no effects on fecal inflammatory markers, diarrheal morbidity, or urine metabolic profiles; but did observe modest reductions in fecal energy and fecal lactoferrin in participants receiving Ala-Gln.

CONCLUSIONS

Intermediate dose Ala-Gln promotes short-term improvement in gut integrity and ponderal growth in children at risk of EE. Lower doses produced improvements in ponderal growth in the absence of enhanced gut integrity.

Efficacy of intramuscular hydroxocobalamin supplementation in cats with cobalamin deficiency and gastrointestinal disease

Background

In humans, absorption and tissue retention rates of intramuscularly administered hydroxocobalamin (OH‐Cbl) are superior compared to cyanocobalamin (CN‐Cbl). Supplementation with OH‐Cbl has not been described in cats.

Objectives

To evaluate effects of parenteral OH‐Cbl supplementation on clinical signs, serum Cbl and methylmalonic acid (MMA) concentrations in hypocobalaminemic cats with gastrointestinal disease.

Animals

Twenty‐three client‐owned cats.

Methods

Prospective study. Serum Cbl and MMA concentrations were determined at enrollment (t0), immediately before the 4th OH‐Cbl IM injection (300 μg, given q2 weeks) (t1), and 4 weeks after the 4th injection (t2). Severity of clinical signs (activity, appetite, vomiting, diarrhea, body weight) was graded at each time point and expressed as clinical disease activity score.

Results

Median clinical disease activity score decreased significantly from t0 (6; range, 2‐10) to t1 (1; range, 0‐6) and t2 (1; range, 0‐9). Median serum Cbl concentration increased significantly from 111 pmol/L (range, 111‐218; reference range, 225‐1451 pmol/L) at t0 to 1612 pmol/L (range, 526‐14 756) (P < .001) at t1, and decreased again significantly to 712 pmol/L (range, 205‐4265) (P < .01) at t2. Median baseline serum MMA concentration at t0 (802 nmol/L; range, 238‐151 000; reference range, 120‐420 nmol/L) decreased significantly (P < .001) to 199 nmol/L (range, 29‐478) at t1, and was 205 nmol/L (range, 88‐734) at t2. Serum MMA concentrations normalized in 22/23 cats at t1, and were not significantly higher at t2 compared to t1.

Conclusions and Clinical Importance

The herein described OH‐Cbl injection scheme appears efficacious for normalization of cellular Cbl deficiency in cats with gastrointestinal disease.

Gut Microbiota Features Associated With Campylobacter Burden and Postnatal Linear Growth Deficits in a Peruvian Birth Cohort

BACKGROUND

Campylobacter infection is associated with impaired growth of children, even in the absence of symptoms. To examine the underlying mechanisms, we evaluated associations between Campylobacter infection, linear growth, and fecal microbial community features in a prospective birth cohort of 271 children with a high burden of diarrhea and stunting in the Amazonian lowlands of Peru.

METHODS

Campylobacter was identified using a broadly reactive, genus-specific enzyme-linked immunosorbent assay. 16S rRNA-based analyses were used to identify bacterial taxa in fecal samples at ages 6, 12, 18, and 24 months (N = 928). Associations between infection, growth, and gut microbial community composition were investigated using multiple linear regression adjusting for within-child correlations, age, and breastfeeding. Indicator species analyses identified taxa specifically associated with Campylobacter burden.

RESULTS

Ninety-three percent (251) of children had Campylobacter present in asymptomatic fecal samples during the follow-up period. A 10% increase in the proportion of stools infected was associated with mean reductions of 0.02 length-for-age z scores (LAZ) at 3, 6, and 9 months thereafter (P < .01). We identified 13 bacterial taxa indicative of cumulative Campylobacter burden and 14 taxa significantly associated with high or low burden of enteroaggregative Escherichia coli, norovirus, or Giardia.

CONCLUSIONS

Campylobacter infection is common in this cohort and associated with changes in microbial community composition. These results support the notion that disruptions to the fecal microbiota may help explain the observed effects of asymptomatic infections on growth in early life.