NOD2 mutations are associated with the development of intestinal failure in the absence of Crohn's disease

Application of enzyme-linked immunosorbent assay to detect antimicrobial peptides in human intestinal lumen

Intestinal transplantation is the definitive treatment for intestinal failure. However, tissue rejection and graft-versus-host disease are relatively common complications, necessitating aggressive immunosuppression that can itself pose further complications. Tracking intraluminal markers in ileal effluent from standard ileostomies may present a noninvasive and sensitive way to detect developing pathology within the intestinal graft. This would be an improvement compared to current assessments, which are limited by poor sensitivity and specificity, contributing to under or over-immunosuppression, respectively, and by the need for invasive biopsies. Herein, we report an approach to reproducibly analyze ileal fluid obtained through stoma sampling for antimicrobial peptide/protein concentrations, reasoning that these molecules may provide an assessment of intestinal homeostasis and levels of intestinal inflammation over time. Concentrations of lysozyme (LYZ), myeloperoxidase (MPO), calprotectin (S100A8/A9) and β-defensin 2 (DEFB2) were assessed using adaptations of commercially available enzyme-linked immunosorbent assays (ELISAs). The concentration of α-defensin 5 (DEFA5) was assessed using a newly developed sandwich ELISA. Our data support that with proper preparation of ileal effluent specimens, precise and replicable determination of antimicrobial peptide/protein concentrations can be achieved for each of these target molecules via ELISA. This approach may prove to be reliable as a clinically useful assessment of intestinal homeostasis over time for patients with ileostomies.

Analysis of circRNA-miRNA-mRNA Regulatory Network in Peripheral Blood of Radiation Workers

The health of radiation workers has always been our focus. Epidemiological investigation shows that long-term exposure to low-dose ionizing radiation can affect human health, especially cancer and cardiovascular disease, and there are many studies on it. However, up to now, there have been few reports on the research of blood and biological samples from radiation workers. In this study, radiation workers and healthy control groups were strictly screened, and the transcriptome of mRNA and circRNA was sequenced by extracting their peripheral venous blood. At the same time, appropriate data sets were selected in the GEO database for bioinformatics analysis, and circRNA-miRNA-mRNA network was constructed. We identified 9 different circular ribonucleic acids, 3 tiny ribonucleic acids, and 2 central genes (NOD 2 and IRF 7). These differentially expressed genes and non-coding RNA are closely related to ionizing radiation damage, and play an important role as biological markers. In conclusion, this study may provide new insights into the role of the circRNA-miRNA-mRNA regulatory network in the health of radiation workers, and provides a new strategy for the future study of radiation biology.

Ileocolonic Healing After Extended Small Bowel Resection in Mice: NOD2 Deficiency Impairs Anastomotic Healing and Postoperative Outcome

BACKGROUND

Nucleotide-binding oligomerization domain-containing protein 2 (NOD2) mutations are a genetic risk factor for Crohn disease. Ileocecal resection is the most often performed surgery in Crohn disease. We investigated the effect of Nod2 knockout (KO) status on anastomotic healing after extended ileocecal resection (ICR) in mice.

METHODS

Male C57BL6/J wild-type and Nod2 KO mice underwent an 11 cm resection of the terminal ileum including the cecum. An end-to-end jejuno-colostomy was performed. Animals were killed after 5 days investigating bursting pressure, hydroxyproline content, and expression of matrix metabolism genes, key cytokines, and histology of the anastomosis.

RESULTS

Mortality was higher in the Nod2 KO group but not because of local or septic complications. Bursting pressure was significantly reduced in the Nod2 KO mice (32.5 vs 78.0 mmHg, P < 0.0024), whereas hydroxyprolin content was equal. The amount of granulation tissue at the anastomosis was similar but more unstructured in the Nod2 KO mice. Gene expression measured by real-time polymerase chain reaction showed significantly increased expression for Collagen 1alpha and for collagen degradation as measured by matrix metalloproteinase-2, -9, and -13 in the Nod2 KO mice. Gelatinase activity from anastomotic tissue was enhanced by Nod2 status. Gene expression of arginase I, tumor necrosis factor-α, and transforming growth factor-ß but not inducible nitric oxide synthase were also increased at the anastomosis in the Nod2 KO mice compared with the control mice.

CONCLUSIONS

We found that Nod2 deficiency results in significantly reduced bursting pressure after ileocecal resection. This effect is mediated via an increased matrix turnover. Patients with genetic NOD2 variations may be prone to anastomotic failure after bowel resection.

Polymorphism nucleotide oligomerization domain-2 (NOD2) in neonatal with early breastfeeding initiation

OBJECTIVE

This study aimed to determine if NOD2 gene polymorphisms are found in neonatal with early breastfeeding initiation and neonatal without early breastfeeding initiation.

METHOD

This study used a Quasy Experiment type, with Non-equivalent Control Group Design. The sample in this study were 60 pregnant women; gestational age±34 and 36 weeks, normal delivery, and carried out early breastfeeding at the Siti Fatima maternal and child hospital and Public Health Center Bara-baraya. The sample was divided into two groups, i.e., the intervention group as many as 30 neonatal and the control group as many as 30 neonatal. Samples were taken from blood from the umbilical cord as much as three cc for the examination of NOD2 polymorphisms.

RESULTS

The group that was given early breastfeeding initiation intervention had a polymorphism frequency of 1 person (3.33%), while the control group had a polymorphism frequency of 4 people (6.67%).

CONCLUSION

The control group, i.e., infants who did not get early breastfeeding initiation had a higher frequency of NOD2 gene mutations compared to the group that received early breastfeeding initiation.

Protein O-GlcNAcylation alleviates small intestinal injury induced by ischemia-reperfusion and oxygen-glucose deprivation

Protein O-GlcNAcylation is a dynamic post-translational protein modification that regulates fundamental cellular functions in both normal physiology and diseases. The levels of protein O-GlcNAcylation are determined by flux of the hexosamine biosynthetic pathway (HBP), which is a branch of glycolysis, and are directly controlled by a pair of enzymes: O-GlcNAc transferase (OGT) and O-GlcNAcase (OGA). An increase in protein O-GlcNAcylation has been shown to have protective effects on ischemia-related insults in the heart and brain. To determine whether O-GlcNAcylation plays a beneficial role in ischemia-reperfusion (IR)-induced intestinal injury, we used pharmacological manipulation of O-GlcNAc to induce loss- and gain-of-function conditions and evaluated the viability and apoptosis of intestinal epithelioid cells in an in vitro oxygen-glucose deprivation (OGD) model and tissue injury grade in a small intestinal ischemia-reperfusion (SIIR) mouse model. We found that 1) Upregulation of O-GlcNAcylation induced by glucosamine (GlcN, increase in HBP flux) or thiamet G (an OGA inhibitor) enhanced intestinal cell survival in the OGD model. In contrast, downregulation of O-GlcNAcylation induced by DON (due to a reduction in HBP flux) or OMSI-1 (an OGT inhibitor) made the cells more susceptible to hypoxia injury. 2) Reducing the increase in O-GlcNAcylation levels with a combination of either GlcN with DON or thiamet G with OMSI-1 partly canceled its protective effect on OGD-induced cell injury. 3) In the in vivo SIIR mouse model, GlcN augmented intestinal protein O-GlcNAcylation and significantly alleviated intestinal injury by inhibiting cell apoptosis. These results indicate that acute increases in protein O-GlcNAcylation confer protection against intestinal ischemia insults, suggesting that O-GlcNAcylation, as an endogenous stress sensor, could be a universal protective mechanism and could be a potential therapeutic target for intestinal ischemic disease.

Factors Associated With 5- and 10-Year Survival After Intestinal Transplantation in Infants and Children

OBJECTIVES

Intestinal transplantation is an option for permanent intestinal failure with parenteral nutrition intolerance. We sought to determine long-term intestinal graft survival in pediatric patients at our center and to identify factors influencing survival.

METHODS

Retrospective chart review of 86 patients transplanted between 2003 and 2013, targeting potential explanatory variables related to demographics, perioperative factors, and postoperative complications.

RESULTS

Intestinal graft survival was 71% and 65% after 5 and 10 years, respectively. Five-year graft survival was attained in 79% of patients with a history of anatomic intestinal failure compared with 45% with functional intestinal failure (P = 0.0055). Compared with nonsurvival, 5-year graft survival was also associated with reduced incidences of graft-versus-host disease (2% vs 16%, P = 0.0237), post-transplant lymphoproliferative disorder (3% vs 24%, P = 0.0067), and de novo donor-specific antibodies (19% vs 57%, P = 0.0451) plus a lower donor-recipient weight ratio (median 0.727 vs 0.923, P = 0.0316). Factors not associated with 5-year intestinal graft survival included graft rejection of any severity and inclusion of a liver graft. Factors associated with graft survival at 10 years were similar to those at 5 years.

CONCLUSIONS

In our experience, outcomes in pediatric intestinal transplantation have improved substantially for anatomic but not functional intestinal failure. Graft survival depends on avoidance of severe infectious and immunological complications including GVHD, whereas inclusion of a liver graft provides no obvious survival benefit. Reduced success with functional intestinal failure may reflect inherently increased susceptibility to complications in this group.

Teduglutide Promotes Epithelial Tight Junction Pore Function in Murine Short Bowel Syndrome to Alleviate Intestinal Insufficiency

BACKGROUND

In short bowel syndrome, epithelial surface loss results in impaired nutrient absorption and may lead to intestinal insufficiency or intestinal failure. Nucleotide oligomerization domain 2 (Nod2) dysfunction predisposes to the development of intestinal failure after intestinal resection and is associated with intestinal barrier defects. Epithelial barrier function is crucial for intestinal absorption and for intestinal adaptation in the short bowel situation.

AIMS

The aim of the study was to characterize the effects of the GLP-2 analogue Teduglutide in the small intestine in the presence and absence of Nod2 in a mouse model of short bowel syndrome.

METHODS

Mice underwent 40% ICR and were thereafter treated with Teduglutide versus vehicle injections. Survival, body weight, stool water, and sodium content and plasma aldosterone concentrations were determined. Intestinal and kidney tissue was examined with light and fluorescence microscopy, Ussing chamber studies and quantitative PCR in wild type and transgenic mice.

RESULTS

Teduglutide reduced intestinal failure incidence in Nod2 k.o. mice. In wt mice, Teduglutide attenuated intestinal insufficiency as indicated by reduced body weight loss and lower plasma aldosterone concentrations, lower stool water content, and lower stool sodium losses. Teduglutide treatment was associated with enhanced epithelial paracellular pore function and enhanced claudin-10 expression in tight junctions in the villus tips, where it colocalized with sodium-glucose cotransporter 1 (SGLT-1), which mediates Na-coupled glucose transport.

CONCLUSIONS

In the SBS situation, Teduglutide not only maximizes small intestinal mucosal hypertrophy but also partially restores small intestinal epithelial function through an altered distribution of claudin-10, facilitating sodium recirculation for Na-coupled glucose transport and water absorption.

Nod2 deficiency functionally impairs adaptation to short bowel syndrome via alterations of the epithelial barrier function

Nucleotide-binding oligomerization domain-containing protein 2 (NOD2) gene mutations are a risk factor for Crohn's disease and also associated with worse outcome in short bowel syndrome (SBS) patients independent of the underlying disease. The aim of this study was to analyze the effect of Nod2 deficiency on barrier function and stool microbiome after extensive ileocecal resection in mice. Male C57BL6/J wild-type (WT) and Nod2-knockout (KO) mice underwent 40% ileocecal resection. Sham control mice received simple transection of the ileum. Clinical outcome was monitored daily. Barrier function was measured with Ussing chambers using FITC-4-kDa-Dextran flux, transmucosal electrical resistance, and dilution potentials. Immunofluorescence of claudin-2 was studied. Composition of the stool microbiome was assessed by 16S rRNA gene sequencing. Resected Nod2-KO mice had impaired clinical outcome compared with resected WT mice. This was accompanied by increased stool water contents and increased plasma aldosterone. Histomorphological adaptation was independent of Nod2. Barrier function studies revealed impaired sodium to chloride permeability and altered claudin-2 localization in the absence of Nod2. Resection induced decreases of bacterial diversity and a shift of bacteriodetes-to-firmicutes ratios. Ileum and cecum resection-induced increase in proteobacteria was absent in Nod2-deficient mice. Verrucomicrobia were temporarily increased in Nod2-KO mice. Nod2 deficiency functionally impairs adaptation to short bowel syndrome via a lesser increase of epithelial sodium pore permeability, altered epithelial barrier function, and the microbiome.NEW & NOTEWORTHYNOD2 gene mutations are associated with the development of severe short bowel syndrome and intestinal failure. The influence of Nod2 mutations on intestinal adaptation in experimental short bowel syndrome has not been studied yet. Here, we provide data that Nod2 deficiency worsens clinical outcome and functional adaptation under SBS conditions in mice, indicating that NOD2 is required for successful adaptation after ileocecal resection.

Reconstructive Surgery for Intestinal Failure

BACKGROUND

Intestinal failure (IF) in the adult is the result of a wide spectrum of disease. Acute mesenteric ischemia, postoperative short bowel due to a complicative course, and Crohn's disease are major causes of IF. Reconstructive surgery in the context of IF comprises a spectrum of procedures including stoma takedown, reversal of laparostomies, and closure of enteric fistulas.

METHODS

This article is based on a PubMed-based literature search and personal experience in adult patients with IF.

RESULTS

This review summarizes therapeutic options of reconstructive surgery in adult patients focusing on the main reasons of IF such as mesenteric ischemia, complicative previous surgery, and Crohn's disease. Indications and contraindications are discussed as well as the optimal time point of reconstructive surgery.

CONCLUSION

This overview summarizes surgical aspects in a special cohort of patients with a rare disease entity necessitating an interdisciplinary approach.

Villus Growth, Increased Intestinal Epithelial Sodium Selectivity, and Hyperaldosteronism Are Mechanisms of Adaptation in a Murine Model of Short Bowel Syndrome

BACKGROUND

Short bowel syndrome results from extensive small bowel resection and induces adaptation of the remaining intestine. Ileocecal resection (ICR) is the most frequent situation in humans. Villus hypertrophy is one hallmark of mucosal adaptation, but the functional mechanisms of mucosal adaptation are incompletely understood.

AIMS

The aim of the study was to characterize a clinically relevant model of short bowel syndrome but not intestinal failure in mice and to identify outcome predictors and mechanisms of adaptation.

METHODS

Male C57BL6/J mice underwent 40% ICR and were followed for 7 or 14 days. Small bowel transection served as control. All mice underwent autopsy. Survival, body weight, wellness score, stool water content, plasma aldosterone concentrations, and paracellular permeability were recorded.

RESULTS

Unlike controls, resected mice developed significant diarrhea with increased stool water. This was accompanied by sustained weight loss throughout follow-up. Villus length increased but did not correlate positively with adaptation. Plasma aldosterone concentrations correlated inversely with body weight at day 14. After ICR, intestinal epithelial (i.e., tight junctional) sodium permeability was increased.

CONCLUSIONS

40% ICR results in moderate to severe short bowel syndrome. Successful adaptation to the short bowel situation involves villus elongation but does not correlate with the degree of villus elongation alone. In addition, increased intestinal epithelial sodium permeability facilitates sodium-coupled solute transport. Hyperaldosteronism correlates with the severity of weight loss, indicates volume depletion, and counterregulates water loss.

Mutations in the NOD2 gene are associated with a specific phenotype and lower anti-tumor necrosis factor trough levels in Crohn's disease

OBJECTIVE

Nucleotide-binding oligomerization domain-containing protein 2 (NOD2) gene mutations are known to be an important risk factor in the pathogenesis of Crohn's disease (CD). Specific disease phenotypes are associated with the presence of NOD2 gene mutation. One treatment option is to use an anti-tumor necrosis factor (TNF)-α agent. Therapeutic drug monitoring (TDM) is usually performed in cases of a loss of response. Our aim was to explore whether NOD2 gene mutations have an effect on the disease phenotype, vitamin D levels, and on TDM in CD patients.

METHODS

This was a retrospective genotype-phenotype association study on NOD2 gene mutations in 161 patients with CD.

RESULTS

Altogether 55 (34.2%) patients carried at least one mutant allele of NOD2. NOD2 gene mutations were associated with ileocecal disease, ileocecal resection, stricturing and perianal disease, and patients with NOD2 gene mutation had significantly less frequent colonic disease and received an ostomy less frequently. TDM in patients with NOD2 gene mutation showed more frequent anti-TNF trough levels in the subtherapeutic range and lower anti-TNF trough levels than in NOD2 wild-type (WT) patients.

CONCLUSIONS

CD patients with NOD2 gene mutation have a specific clinical phenotype and they may require higher doses of anti-TNF agents to achieve sufficient anti-TNF trough levels. They may therefore benefit from a proactive TDM than a reactive approach. This could be another step in the direction of personalized medicine.

Intestinal Transplant Inflammation: the Third Inflammatory Bowel Disease

Intestinal transplantation is the most immunologically complex of all abdominal organ transplants. Understanding the role both humoral and innate and adaptive cellular immunity play in intestinal transplantation is critical to improving outcomes and increasing indications for patients suffering from intestinal failure. Recent findings highlighting the impact of donor-specific antibodies on intestinal allografts, the role of NOD2 as a key regulator of intestinal immunity, the protective effects of innate lymphoid cells, and the role of Th17 in acute cellular rejection are reviewed here.

The microbiome and its implications in intestinal transplantation

PURPOSE OF REVIEW

This article summarizes the complex interplay between the microbiota and host immune responses, and its impact on intestinal transplantation and allograft rejection.

RECENT FINDINGS

Recent findings highlight the importance of Paneth cells as crucial producers of antimicrobial peptides that control the intestinal host-microbial interface as well as the essential role of NOD2 as a master regulator of antimicrobial host defenses. Moreover, complex interactions between innate and adaptive immune responses have been shown to critically shape host antimicrobial Th17 responses, which may be key for the pathogenesis of inflammatory bowel diseases and intestinal allograft rejection.

SUMMARY

A growing body of evidence indicates that crosstalk between the microbiome and innate and adaptive host immunity determines alloimmune responses and outcomes in intestinal transplantation. Elaboration of this emerging field might lead to novel mechanistic insight into these complex interactions and allow for new therapeutic approaches.

Nutritional strategies to enhance adaptation in intestinal failure

PURPOSE OF REVIEW

This article summarizes the current and potential future nutritional approaches to stimulate adaptation in intestinal failure. Adaptation in this context usually refers to intestinal adaptation but also involves changes in whole body physiology as well as in eating/drinking behavior.

RECENT FINDINGS

Adaptation largely depends on residual functional anatomy. Luminal exposure to complex nutrients is the most important trigger for intestinal adaptation. Enteral fat as well as enteral or parenteral short chain fatty acids have a specific stimulatory effect. Zinc and vitamin A status need to be optimized for adaptation to proceed and be maintained. In the context of maintaining sodium and water homeostasis, flushing the remnant intestine because of uncontrolled thirst/drinking must be avoided. Complications of nutritional care such as malnutrition, intestinal failure-associated liver disease, and recurrent line sepsis also need optimal management.

SUMMARY

Stimulation by luminal nutrients as well as prophylaxis against and treatment of (nutritional) complications are the cornerstones of adaptation to the short bowel situation. Based on ample data from animal studies but only limited evidence in humans specific nutritional stimulators need to be studied more rigorously. As long as such data are missing they can be tried on an individual basis.

Management of Crohn's Disease in the New Era of Gut Rehabilitation and Intestinal Transplantation

Despite recent therapeutic advances, patients with Crohn's disease (CD) continue to experience high recurrence with cumulative structural damage and ultimate loss of nutritional autonomy. With short bowel syndrome, strictures, and enteric fistulae being the underlying pathology, CD is the second common indication for home parenteral nutrition (HPN). With development of intestinal failure, nutritional management including HPN is required as a rescue therapy. Unfortunately, some patients do not escape the HPN-associated complications. Therefore, the concept of gut rehabilitation has evolved as part of the algorithmic management of these patients, with transplantation being the ultimate life-saving therapy. With type 2 intestinal failure, comprehensive rehabilitative measures including nutritional care, pharmacologic manipulation, autologous reconstruction, and bowel lengthening is often successful, particularly in patients with quiescent disease. With type 3 intestinal failure, transplantation is the only life-saving treatment for patients with HPN failure and intractable disease. With CD being the second common indication for transplantation in adults, survival outcome continues to improve because of surgical innovation, novel immunosuppression, and better postoperative care. Despite being a rescue therapy, the procedure has achieved survival rates similar to other solid organs, and comparable to those who continue to receive HPN therapy. With similar technical, immunologic, and infectious complications, survival is similar in the CD and non-CD recipients. Full nutritional autonomy is achievable in most survivors with better quality of life and long-term cost-effectiveness. CD recurrence is rare with no impact on graft function. Further progress is anticipated with new insights into the pathogenesis of CD and mechanisms of transplant tolerance.

Alterations in the mucosa-associated bacterial composition in Crohn's disease: a pilot study

INTRODUCTION

Changes in the intestinal bacterial composition seem to play a major role in the pathogenesis and in the clinical course of inflammatory bowel diseases (IBD), which consist of Crohn's disease (CD), and ulcerative colitis (UC). Mutations in the NOD2 gene are the most important genetic risk factors for the development of CD. In this study, the association between mucosal biopsies and the mucosa-associated bacterial composition from CD and UC patients regarding their genetic risk factors (mutations in the NOD2 gene), their endoscopic activity, and their medical therapy (TNF-α blocking therapy) was examined.

MATERIAL AND METHODS

Seventy biopsies from routine colonoscopies from 33 IBD patients (26 CD and 7 UC) were obtained. Disease activity and clinical characteristics were assessed. Seven different bacterial strains (Bacteroides fragilis, Escherichia coli, Prevotella melaninogenica, Clostridium coccoides, Clostridium difficile, Bifidobacterium bifidum, and Faecalibacterium prausnitzii) were quantified using real-time PCR. NOD2 genotyping from patients with CD was performed.

RESULTS

Five of the 24 patients were positive for at least one mutation in the NOD2 gene. The bacterial composition was different in CD compared to UC, in macroscopic healthy compared to macroscopic inflamed biopsies, in NOD2 mutated compared to NOD2 wildtype patients, and in patients receiving TNF-α blocking therapy compared to patients without this treatment.

CONCLUSION

This study further characterizes the mucosa-associated bacteria in IBD patients. Different clinical situations lead to an altered mucosa-associated bacterial composition. The analyzed bacteria could be promising targets for cost-effective surveillance or therapies in IBD patients.

Chronic mucosal inflammation/inflammatory bowel disease-like inflammation after intestinal transplantation: where are we now?

PURPOSE OF REVIEW

The purpose of this review is to highlight the similarities between inflammatory bowel disease and the state of the intestine allograft after transplantation.

RECENT FINDINGS

The mutant nucleotide-binding oligomerization protein 2 (NOD2) gene, which encodes for an intracellular protein that serves as an innate immune system microbial sensor in macrophages, dendritic cells, and certain intestinal epithelial cells, has been recognized as a risk factor in Crohn's disease. Similarly, recent studies have also highlighted the contribution the NOD2 mutation may have on intestinal failure itself. More specifically, in intestinal transplant recipients with the NOD2 mutation, the discovery of the reduced ability to prevent bacterial clearance, increased enterocyte stress response, and failure of key downstream expression of important cytokines and growth factors have been implicated as major factors in intestinal transplant outcomes, namely graft loss and septic death. Treatment strategies with anti tumor necrosis factor (TNF) α, similar to inflammatory bowel disease, have been employed in intestinal transplantation with promising results.

SUMMARY

In intestinal transplantation, there is evidence that the classical alloimmunity pathways that lead toward graft dysfunction and eventual graft loss may, in fact, be working in concert with a disordered innate immune system to produce a state of chronic inflammation not unlike that seen in inflammatory bowel disease.

Management of intestinal failure in inflammatory bowel disease: small intestinal transplantation or home parenteral nutrition?

Inflammatory bowel disease and Crohn's disease in particular, is a common cause of intestinal failure. Current therapeutic options include home parenteral nutrition and intestinal transplantation. For most patients, home intravenous therapy including parenteral nutrition, with a good probability of long-term survival, is the favoured choice. However, in selected patients, with specific features that may shorten survival or complicate home parenteral nutrition, intestinal transplantation presents a viable alternative. We present survival, complications, quality of life and economic considerations that currently influence individualised decision-making between home parenteral nutrition and intestinal transplantation.

Two patients with intestinal failure requiring home parenteral nutrition, a NOD2 mutation and tuberculous lymphadenitis

Background

Mutations in the NOD2 gene are a significant risk factor to acquire intestinal failure requiring home parenteral nutrition. Tuberculous lymphadenitis is the main manifestation of extrapulmonary tuberculosis. Defects in the innate immunity, including NOD2 mutations, may increase the risk for acquiring infections caused by M. tuberculosis. An association of intestinal failure, mutations in the NOD2 gene and tuberculous lymphadenitis has not been described before.

Case presentation

We report of two patients with intestinal failure secondary to mesenteric ischemia. Both patients presented with fever and weight loss while receiving long term home parenteral nutrition. Both of them were found to have mutations in the NOD2 gene. Catheter related infections were ruled out. FDG-PET-CT scans initially obtained in search for another infectious focus that would explain the symptoms unexpectedly showed high FDG uptake in mediastinal lymph nodes. Direct or indirect evidence proved or was highly suggestive for tuberculous lymphadenitis. Intravenous tuberculostatic therapy was started and led to a reversal of symptoms and to resolution of the lesions by FDG-PET-CT.

Conclusion

Mutations in the NOD2 gene may put patients both at an increased risk for acquiring M. tuberculosis infections as well as at an increased risk of intestinal failure after extensive intestinal resection. Thus we suggest to specifically include reactivated and opportunistic infections in the differential diagnosis of suspected catheter related infection in patients with intestinal failure who carry mutations in their NOD2 gene.