Blood gene expression biomarkers of response to anti-TNF drugs in pediatric inflammatory bowel diseases before initiation of treatment

BACKGROUND/AIMS

Changes in gene expression profiles among individuals with inflammatory bowel diseases (IBDs) could potentially influence the responsiveness to anti-TNF treatment. The aim of this study was to identify genes that could serve as predictors of early response to anti-TNF therapies in pediatric IBD patients prior to the initiation of treatment.

METHODS

We conducted a prospective, longitudinal, and multicenter study, enrolling 24 pediatric IBD patients aged less than 18 years who were initiating treatment with either infliximab or adalimumab. RNA-seq from blood samples was analyzed using the DESeq2 library by comparing responders and non-responders to anti-TNF drugs.

RESULTS

Bioinformatic analyses unveiled 102 differentially expressed genes, with 99 genes exhibiting higher expression in responders compared to non-responders prior to the initiation of anti-TNF therapy. Functional enrichment analyses highlighted defense response to Gram-negative bacteria (FDR = 2.3 ×10-7) as the most significant biological processes, and hemoglobin binding (FDR = 0.002), as the most significant molecular function. Gene Set Enrichment Analysis (GSEA) revealed notable enrichment in transcriptional misregulation in cancer (FDR = 0.016). Notably, 13 genes (CEACAM8, CEACAM6, CILP2, COL17A1, OLFM4, INHBA, LCN2, LTF, MMP8, DEFA4, PRTN3, AZU1, and ELANE) were selected for validation, and a consistent trend of increased expression in responders prior to drug administration was observed for most of these genes, with findings for 4 of them being statistically significant (CEACAM8, LCN2, LTF2, and PRTN3).

CONCLUSIONS

We identified 102 differentially expressed genes involved in the response to anti-TNF drugs in children with IBDs and validated CEACAM8, LCN2, LTF2, and PRTN3. Genes participating in defense response to Gram-negative bacterium, serine-type endopeptidase activity, and transcriptional misregulation in cancer are good candidates for anticipating the response to anti-TNF drugs in children with IBDs.

Polymorphisms indicating risk of inflammatory bowel disease or antigenicity to anti-TNF drugs as biomarkers of response in children

Few genetic polymorphisms predict early response to anti-TNF drugs in inflammatory bowel disease (IBD), and even fewer have been identified in the pediatric population. However, it would be of considerable clinical interest to identify and validate genetic biomarkers of long-term response. Therefore, the aim of the study was to analyze the usefulness of biomarkers of response to anti-TNFs in pediatric IBD (pIBD) as long-term biomarkers and to find differences by type of IBD and type of anti-TNF drug. The study population comprised 340 children diagnosed with IBD who were treated with infliximab or adalimumab. Genotyping of 9 selected SNPs for their association with early response and/or immunogenicity to anti-TNFs was performed using real-time PCR. Variants C rs10508884 (CXCL12), A rs2241880 (ATG16L1), and T rs6100556 (PHACTR3) (p value 0.049; p value 0.03; p value 0.031) were associated with worse long-term response to anti-TNFs in pIBD. DNA variants specific to disease type and anti-TNF type were identified in the pediatric population. Genotyping of these genetic variants before initiation of anti-TNFs would enable, if validated in a prospective cohort, the identification of pediatric patients who are long-term responders to this therapy.

Association between HLA DNA Variants and Long-Term Response to Anti-TNF Drugs in a Spanish Pediatric Inflammatory Bowel Disease Cohort

The genetic polymorphisms rs2395185 and rs2097432 in HLA genes have been associated with the response to anti-TNF treatment in inflammatory bowel disease (IBD). The aim was to analyze the association between these variants and the long-term response to anti-TNF drugs in pediatric IBD. We performed an observational, multicenter, ambispective study in which we selected 340 IBD patients under 18 years of age diagnosed with IBD and treated with anti-TNF drugs from a network of Spanish hospitals. Genotypes and failure of anti-TNF drugs were analyzed using Kaplan-Meier curves and Cox logistic regression. The homozygous G allele of rs2395185 and the C allele of rs2097432 were associated with impaired long-term response to anti-TNF drugs in children with IBD after 3 and 9 years of follow-up. Being a carrier of both polymorphisms increased the risk of anti-TNF failure. The SNP rs2395185 but not rs2097432 was associated with response to infliximab in adults with CD treated with infliximab but not in children after 3 or 9 years of follow-up. Conclusions: SNPs rs2395185 and rs2097432 were associated with a long-term response to anti-TNFs in IBD in Spanish children. Differences between adults and children were observed in patients diagnosed with CD and treated with infliximab.

Takayasu's arteritis as an incidental finding in a patient with celiac disease: the importance of positron emission computed tomography

BACKGROUND

Takayasu arteritis is a large-vessel vasculitis which affects large-caliber elastic arteries, primarily the aorta and its main branches. It mainly affects women between 20-30 years, so it is rare in children.

CASE REPORT

We describe the case of a 15-year-old female who was followed up since she was 9 years old due to celiac disease. At the age of 13, anaemia of chronic disorders associated to elevated C-reactive protein and erythrocyte sedimentation were detected. The patient remained asymptomatic. After excluding other diseases, we requested a positron emission computed tomography (PET-CT); lesions compatible with large-vessel vasculitis were detected. Cardiology evaluation showed an aneurysm in the right coronary artery. Angio-CT suggested Takayasu type III arteritis.

CONCLUSIONS

The delay in the diagnosis of Takayasu arteritis in pediatric patients is quite common. In this case, we have found phase II lesions, with no previous phase I symptoms. However, PET-CT allowed the diagnosis of vasculitis, key to the diagnosis of the patient.

Vitamin D Status in Pediatric and Young Adult Cystic Fibrosis Patients. Are the New Recommendations Effective?

Introduction: In recent years, guidelines for vitamin D supplementation have been updated and prophylactic recommended doses have been increased in patients with cystic fibrosis (CF). Objective: To evaluate safety and efficacy of these new recommendations. Results: Two cohorts of pancreatic insufficient CF patients were compared before (cohort 1: 179 patients) and after (cohort 2: 71 patients) American CF Foundation and European CF Society recommendations were published. Cohort 2 patients received higher Vitamin D doses: 1509 (1306–1711 95% CI) vs 1084 (983–1184 95% CI) IU/Day (p < 0.001), had higher 25 OH vitamin D levels: 30.6 (27.9–33.26 95% CI) vs. 27.4 (25.9–28.8 95% CI) ng/mL (p = 0.028), and had a lower prevalence of insufficient vitamin D levels (<30 ng/mL): 48% vs 65% (p = 0.011). Adjusted by confounding factors, patients in cohort 1 had a higher risk of vitamin D insufficiency: OR 2.23 (1.09–4.57 95% CI) (p = 0.028). Conclusion: After the implementation of new guidelines, CF patients received higher doses of vitamin D and a risk of vitamin D insufficiency decreased. Despite this, almost a third of CF patients still do not reach sufficient serum calcidiol levels.

Neonatal cystic fibrosis screening: Analysis and differences in immunoreactive trypsin levels in newborns with a positive screen

INTRODUCTION

Neonatal cystic fibrosis (CF) screening has enabled the disease to be diagnosed early, and is a determining factor in the increase in survival of these patients. Its main disadvantage is its low specificity and elevated number of false positives. The aim of this study is to analyse the differences in immunoreactive trypsin (IRT) between the different groups of newborns (NB) with a positive neonatal screen depending on whether they were healthy, healthy carriers, affected by CF, or CFSPID (Cystic Fibrosis Screen Positive, Inconclusive Diagnosis).

MATERIAL

Retrospective analytical study of the concentrations of IRT in NB with a positive neonatal screen for CF born in a tertiary hospital during an 8-year period.

RESULTS

A total of 790 NB with a positive neonatal screen for CF were analysed. Of these 86.3% were term, 53% girls, and 11.8% were admitted. The mean IRT value was 79.16 ng/mL (range 60-367). Significantly higher concentrations of IRT were found in those affected by CF compared to the other groups (P < .001). There were higher levels in large prematures (P = .007) and admitted patients (P = .002). There were no differences as regards gender or season. There was a direct correlation of 64% (P = .001) between IRT and sweat test in those affected by CF and CFSPID. A cut-off value of IRT for the diagnosis of CF was calculated from the ROC curve (76.2 ng/mL (S = 95.7%, Sp = 64.5%).

CONCLUSIONS

NB with CF have significantly higher levels of IRT than healthy ones, or carriers and CFSPID. Prematurity and hospital admission may also have an influence. A higher IRT value is associated with a higher level in the sweat test.

Pharmacogenetics of trough serum anti-TNF levels in paediatric inflammatory bowel disease

AIMS

Identifying DNA variants associated with trough serum anti-tumour necrosis factor (TNF) levels could predict response to treatment in inflammatory bowel disease (IBD). To date, no specific studies have been performed in children. The aim of this study was to identify genetic variants associated with trough serum anti-TNF levels and whether these variants are differential markers for infliximab and adalimumab.

METHODS

We included 154 children (age < 18 years) from 17 hospitals who had been diagnosed with IBD and actively treated with infliximab or adalimumab. Twenty-one polymorphisms were genotyped using real-time PCR. Trough serum anti-TNF levels were measured using enzyme-linked immunosorbent assay (ELISA). The association between DNA polymorphisms and the therapeutic range or the absolute values of anti-TNF drugs was analysed by Fisher exact test, student's t-test and logistic regression.

RESULTS

The variants rs5030728 (TLR4) and rs11465996 (LY96) were associated with subtherapeutic infliximab levels. rs1816702 (TLR2) was associated with supratherapeutic levels and rs3397 (TNFRSF1B) with subtherapeutic levels of adalimumab (P < .05). In addition, rs1816702 (TLR2) and rs2569190 (CD14) were associated with absolute values of trough serum adalimumab, and rs2569190 (CD14) was associated with absolute values of trough serum adalimumab and infliximab (P < .05).

CONCLUSION

Genotyping of these DNA variants before starting treatment may help to select the best anti-TNF drug in paediatric patients. The SNP rs1816702 is the most promising marker for tailoring the anti-TNF regimen in children with IBD. For the first time, DNA variants are associated with trough serum anti-TNF levels.

Predictors of Response to Exclusive Enteral Nutrition in Newly Diagnosed Crohn´s Disease in Children: PRESENCE Study from SEGHNP

Exclusive enteral nutrition (EEN) has been shown to be more effective than corticosteroids in achieving mucosal healing in children with Crohn´s disease (CD) without the adverse effects of these drugs. The aims of this study were to determine the efficacy of EEN in terms of inducing clinical remission in children newly diagnosed with CD, to describe the predictive factors of response to EEN and the need for treatment with biological agents during the first 12 months of the disease. We conducted an observational retrospective multicentre study that included paediatric patients newly diagnosed with CD between 2014–2016 who underwent EEN. Two hundred and twenty-two patients (140 males) from 35 paediatric centres were included, with a mean age at diagnosis of 11.6 ± 2.5 years. The median EEN duration was 8 weeks (IQR 6.6–8.5), and 184 of the patients (83%) achieved clinical remission (weighted paediatric Crohn’s Disease activity index [wPCDAI] < 12.5). Faecal calprotectin (FC) levels (μg/g) decreased significantly after EEN (830 [IQR 500–1800] to 256 [IQR 120–585] p < 0.0001). Patients with wPCDAI ≤ 57.5, FC < 500 μg/g, CRP >15 mg/L and ileal involvement tended to respond better to EEN. EEN administered for 6–8 weeks is effective for inducing clinical remission. Due to the high response rate in our series, EEN should be used as the first-line therapy in luminal paediatric Crohn’s disease regardless of the location of disease and disease activity.

Analysis of the Spanish national registry for pediatric home enteral nutrition (NEPAD): implementation rates and observed trends during the past 8 years

BACKGROUND/OBJECTIVES

The home enteral nutrition (HEN) provides nutritional support to children with chronic diseases who are nutritionally compromised and allows them to be discharged more quickly from hospitals. In 2003, a web-based registry (Nutrición Enteral Pediátrica Ambulatoria y Domiciliaria, Pediatric Ambulatory and Home Enteral Nutrition -NEPAD-) was created with the objective of gathering information about pediatric HEN practices in Spain.

AIM

The aim of this study was to report the implementation of the NEPAD (Nutrición Enteral Pediátrica Ambulatoria y Domiciliaria, Pediatric Ambulatory and Home Enteral Nutrition) registry of pediatric HEN in Spain and to analyze data evolution trends from 2003 to 2010.

SUBJECTS/METHODS

The data from the Spanish NEPAD registry were analyzed according to the following variables: demographic data, diagnosis, indication for HEN, nutritional support regime and administration route.

RESULTS

Over the study period, 952 patients (1048 episodes) from 20 Spanish hospitals were included in the NEPAD registry. The most frequent indication for HEN was decreased oral intake (64%), and neurological disease was the most prevalent illness. HEN was delivered via a nasogastric tube in 573 episodes (54.7%), by gastrostomy in 375 episodes (35.8%), oral feeding in 77 episodes (7.3%) and by jejunal access in 23 episodes (2.2%). Significant differences in the mode of administration were observed based on the pathology of the child (χ(2), P<0.0001). The cyclic feeding was the most widely used technique for the administration of HEN. Most of the patients used a pump and a polymeric formula. Transition to oral feeding was the primary reason for discontinuation of this type of support.

CONCLUSIONS

Since the NEPAD registry was established in Spain, the number of documented patients has increased more than 25-fold. Many children with chronic illness benefit from HEN, mainly those suffering from neurological diseases.

[Benign paroxysmal vertigo. Our 14 years' experience with this entity]

INTRODUCTION

Benign paroxysmal vertigo (BPV) is characterised by the sudden onset of brief recurring episodes of loss of balance, sometimes accompanied by vegetative symptoms, which tend to disappear spontaneously in a matter of months or years and have no intercritical alterations.

PATIENTS AND METHODS

We analyse the clinical and developmental characteristics of the patients who were listed as possible cases of benign paroxysmal vertigo in the database of the Neuropaediatric Unit of the Hospital Miguel Servet in Zaragoza over a 14 year period. Clinical records were reviewed and cases no longer controlled were contacted by telephone.

RESULTS

18 patients were considered to be cases of BPV, with the typical criteria, and 13 were found to be possible BPV (p-BPV). The atypical data of the p-BPV included late age of onset, prolonged persistence of the episodes and long duration of each episode. Neuroimaging was performed in 8 (44%) of the BPV and 10 (77%) of the p-BPV, and electroencephalogram recordings were carried out in 15 (83%) of the BPV and 11 (85%) of the p-BPV, with normal results in all cases.

CONCLUSIONS

Establishing a diagnosis of BPV with strict criteria can mean that some atypical cases are excluded. As no biological marker is available, the diagnosis is clinical-developmental and sometimes complementary tests need to be conducted in order to rule out other pathological conditions. A broader clinical spectrum, cases in which the episodes last longer and a greater range of ages of onset and complete remission are all possible. A diagnosis of BPV should reassure the patients' families as it is a benign process that tends to disappear spontaneously.

[Severe fulminant form of neonatal citrullinemia. Report of a case]

INTRODUCTION

Citrullinemia is an autosomal recessive disease, which is caused by a deficiency of the argininosuccinate synthetase. The neonatal forms are serious and many times are associated with a high level of mortality.

CASE REPORT

A newborn that came in again on her third day of life due to a apneic episodes which required mechanical ventilation. Previously, she rejected feeding, had poor suction, lethargy and remarkable hypoactivity. During the following hours, she showed serious neurologycal deterioration with multifocal convulsions and coma, passing away 20 hours after admission due to endocraneal hypertension. The metabolic evaluation confirmed very significant hyperammonemia, with important increase of citrullin and glutamin, and arginine in the low limits of normality. She was treated with sodium benzoate and arginine and she also needed exanguinotransfusion. It was not possible to put her on hemodyalisis. The findings of the autopsy confirmed massive cerebral edema and characteristic hystological changes in the liver. The determination of the enzymatical activity in liver tissue showed a partial deficiency, with a residual activity of 25% of the average control.

CONCLUSIONS

This is a case of fulminant neonatal citrullinemia that we considered of interest in order to draw the attention of the clinical on this type of diseases. The prognosis depends on early diagnosis, witch is based on clinical suspicion and analytical determination of ammonia in every newborn with unexplained vomiting, lethargy or other symptoms of encephalopathy.