Emerging Insights on the Interaction Between Anticancer and Immunosuppressant Drugs and Intestinal Microbiota in Pediatric Patients

Diseases affecting the immune system, such as inflammatory bowel disease (IBD), juvenile idiopathic arthritis (JIA), and acute lymphoblastic leukemia (ALL), are pathological conditions affecting the pediatric population and are often associated with alterations in the intestinal microbiota, such as a decrease in bacterial diversity. Growing evidence suggests that gut microbiota can interfere with chemotherapeutic and immunosuppressant drugs, used in the treatment of these diseases, reducing or facilitating drug efficacy. In particular, the effect of intestinal microflora through translocation, immunomodulation, metabolism, enzymatic degradation, and reduction of bacterial diversity seems to be one of the reasons of interindividual variability in the therapeutic response. Although the extent of the role of intestinal microflora in chemotherapy and immunosuppression remains still unresolved, current evidence on bacterial compositional shifts will be taken in consideration together with clinical response to drugs for a better and personalized therapy. This review is focused on the effect of the intestinal microbiota on the efficacy of pharmacological therapy of agents used to treat IBD, JIA, and ALL

Enteral bleeding in a former preterm girl with short bowel syndrome: Do not miss the diagnosis

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Impact of the first COVID-19 lockdown on the relationship with parents and peers in a cohort of adolescents with somatic symptom disorder

To investigate the coping strategies of a group of adolescents with somatic symptom disorder compared to non-somatic symptom disorder peers during the COVID-19 related lockdown.This cross-sectional study is the second part of a previously published study showing an improved trend in depression and anxiety in a group of patients with somatic symptom disorder compared to non-somatic symptom disorder peers. An anonymous semi-structured survey was distributed to two groups of Italian adolescents to measure the impact of quarantine on their daily life and coping strategies.We recruited 115 adolescents, 58 (50.4%) mean age 15.3, with a recent diagnosis of somatic symptom disorder and 57 (49.6%) mean age 15.8, control peers.The aim of this study was to detect differences in coping strategies and relationships with parents and peers, during the lockdown period in a group of adolescents with somatic symptom disorder and low disease burden when compared with a non-somatic symptom disorder group.The relationship with parents significantly worsened in 4 (6.9%) of adolescents with somatic symptom disorder compared to 12 (21.1%) adolescents in the non-somatic symptom disorder group (p = 0.048). The relationship with peers significantly improved in 13 (22.4%) of adolescents with symptom disorder versus 3 (5.3%) of peers of the non- somatic symptom disorder group (p = 0.013).Adolescents with somatic symptom disorder with a low burden of physical symptoms experienced less deterioration in their relationships with parents and peers than the non-somatic symptom disorder group

Azathioprine Biotransformation in Young Patients with Inflammatory Bowel Disease: Contribution of Glutathione-S Transferase M1 and A1 Variants

The contribution of candidate genetic variants involved in azathioprine biotransformation on azathioprine efficacy and pharmacokinetics in 111 young patients with inflammatory bowel disease was evaluated. Azathioprine doses, metabolites thioguanine-nucleotides (TGN) and methylmercaptopurine-nucleotides (MMPN) and clinical effects were assessed after at least 3 months of therapy. Clinical efficacy was defined as disease activity score below 10. Candidate genetic variants (TPMT rs1142345, rs1800460, rs1800462, GSTA1 rs3957357, GSTM1, and GSTT1 deletion) were determined by polymerase chain reaction (PCR) assays and pyrosequencing. Statistical analysis was performed using linear mixed effects models for the association between the candidate variants and the pharmacological variables (azathioprine doses and metabolites). Azathioprine metabolites were measured in 257 samples (median 2 per patient, inter-quartile range IQR 1-3). Clinical efficacy at the first evaluation available resulted better in ulcerative colitis than in Crohn's disease patients (88.0% versus 52.5% responders, p = 0.0003, linear mixed effect model, LME). TGN concentration and the ratio TGN/dose at the first evaluation were significantly higher in responder. TPMT rs1142345 variant (4.8% of patients) was associated with increased TGN (LME p = 0.0042), TGN/dose ratio (LME p < 0.0001), decreased azathioprine dose (LME p = 0.0087), and MMPN (LME p = 0.0011). GSTM1 deletion (58.1% of patients) was associated with a 18.5% decrease in TGN/dose ratio and 30% decrease in clinical efficacy. GSTA1 variant (12.8% of patients) showed a trend (p = 0.049, LME) for an association with decreased clinical efficacy; however, no significant effect on azathioprine pharmacokinetics could be detected. In conclusion, GSTs variants are associated with azathioprine efficacy and pharmacokinetics

Long non-coding RNA gas5 and intestinal mmp2 and mmp9 expression: A translational study in pediatric patients with IBD

Background: The long non-coding RNA (lncRNA) growth arrest–specific transcript 5 (GAS5) seems to be involved in the regulation of mediators of tissue injury, in particular matrix metalloproteinases (MMPs), implicated in the pathogenesis of inflammatory bowel disease (IBD). We investigated the role of GAS5 in regulating MMP2 and MMP9 expression in pediatric patients with IBD and in vitro. Methods: In total, 25 IBD patients were enrolled: For each patient paired inflamed and non-inflamed biopsies were collected. RNA was extracted and GAS5, MMP2, and MMP9 were quantified by TaqMan assay. The expression of GAS5 and MMPs was also determined in the human monocytic THP1 cells differentiated into macrophages and stimulated with lipopolysaccharide (LPS). The function of GAS5 was assessed by overexpressing the lncRNA and evaluating the MMPs levels. Results: Real-time PCR results demonstrated a downregulation of GAS5 and an upregulation of both MMPs in inflamed tissues. In vitro data confirmed the trend observed in patients for the three genes: The stimulation with LPS promoted a downregulation of GAS5 while an increase of MMPs was observed. Overexpression experiments showed that higher levels of GAS5 lead to a decrease of both enzymes. Conclusion: These results provide new information about the role of GAS5 in IBD: The lncRNA could mediate tissue damage by modulating the expression of MMPs

Therapeutic drug monitoring in pediatric IBD: Current application and future perspectives

BACKGROUND:as the paradigm for IBD management is evolving from symptom control to the more ambitious goal of complete deep remission, the concept of personalized medicine, as a mean to deliver individualized treatment with the best effectiveness and safety profile, is becoming paramount. Therapeutic drug monitoring (TDM) is an essential part of personalized medicine and its role in the management of IBD patients is rapidly expanding. OBJECTIVE:to review the current knowledge that poses the rationale for the use of TDM, and the present and future role of TDM-based approaches in the management of pediatric IBD. METHOD:literature review. RESULTS:the concept of TDM has been introduced in the field of IBD along with thiopurines, over a decade ago, and evolved around anti-TNF therapies. TDM-based strategies proved to be costeffective in the management of patients with loss of response to biologics and, more recently, proactive TDM to optimize drug exposure has been shown to reduce treatment failure and drug adverse events. The role of TDM with new biologics and the usefulness of software-systems support tools to guide drug dosing are now under investigation. CONCLUSION:Therapeutic drug monitoring has the potential to maximize the cost-benefit profile of therapies and is becoming an essential part of IBD management

Stop considering atopic dermatitis as an allergic disease.

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Case Report: Refractory Autoimmune Gastritis Responsive to Abatacept in LRBA Deficiency

Primary immunodeficiency (PID) with immune dysregulation may present with early onset gastrointestinal autoimmune disorders. When gastrointestinal autoimmunity is associated with multiple extraintestinal immune system dysfunction the diagnosis of PID is straightforward. However, with the advent of next generation sequencing technologies, genetic defects in PID genes have been increasingly recognized even when a single or no extraintestinal signs of immune dysregulation are present. A genetic diagnosis is especially important considering the expanding armamentarium of therapies designed to inhibit specific molecular pathways. We describe a boy with early-onset severe, refractory autoimmune gastritis and biallelic mutations in the LRBA gene causing a premature STOP-codon who was successfully treated with CTLA4-Ig, abatacept, with long term clinical and endoscopic remission. The case underscores the importance to consider a monogenetic defect in early onset autoimmune disorders, since the availability of targeted treatments may significantly improve patient prognosis

Role of tristetraprolin phosphorylation in paediatric patients with inflammatory bowel disease

BACKGROUND Intestinal inflammation and epithelial injury are the leading actors of inflammatory bowel disease (IBD), causing an excessive pro-inflammatory cytokines expression. Tristetraprolin (TTP), an mRNA binding protein, plays a role in regulating the inflammatory factors, recognizing specific sequences on the 3\u2019 untranslated region of cytokine mRNAs. TTP activity depends on its phosphorylation state: the unphosphorylated TTP degrades pro-inflammatory cytokine mRNAs; on the contrary, the phosphorylated TTP fails to destabilize mRNAs furthering their expression. The phospho-TTP forms a complex with the chaperone protein 14-3-3. This binding could be one of the factors that promote intestinal inflammation as a cause of disease progression. AIM To assess if TTP phosphorylation has a role in paediatric IBD. METHODS The study was carried out on a cohort of paediatric IBD patients. For each patient enrolled, a specimen of inflamed and non-inflamed colonic mucosa was collected. Furthermore, the experiments were conducted on macrophages differentiated from blood samples of the same patients. Macrophages from healthy donors\u2019 blood were used as controls. Co-immunoprecipitation assay and immunoblotting analyses were performed to observe the formation of the phospho-TTP/14-3-3 complex. In the same samples TNF-\u3b1 expression was also evaluated as major factor of the pro-inflammatory activity. RESULTS In this work we studied indirectly the phosphorylation of TTP through the binding with the chaperone protein 14-3-3. In inflamed and non-inflamed colon mucosa of IBD paediatric patients immunoblot assay demonstrated a higher expression of the TTP in inflamed samples respect to the non-inflamed; the co-immunoprecipitated 14-3-3 protein showed the same trend of expression. In the TNF-\u3b1 gene expression analysis higher levels of the cytokine in inflamed tissues compared to controls were evident. The same experiments were conducted on macrophages from IBD paediatric patients and healthy controls. The immunoblot results demonstrated a high expression of both TTP and co-immunoprecipitated 14-4-3 protein in IBD-derived macrophages in comparison to healthy donors. TNF-\u3b1 protein levels from macrophages lysates showed the same trend of expression in favour of IBD paediatric patients compared to healthy controls. CONCLUSION In this work, for the first time, we describe a relation between phospho-TTP/14-3-3 complex and IBD. Indeed, a higher expression of TTP/14-3-3 was recorded in IBD samples in comparison to controls

Thromboembolism in pediatric inflammatory bowel disease: Systematic review

BACKGROUND: Several studies suggest an increased risk of venous and arterial thromboembolism (TE) in adults with inflammatory bowel disease (IBD) compared to the general population. We performed a systematic review of studies on incidence and characteristic of TE in children with IBD. METHODS: We searched Medline, LILACS, EMBASE, POPLINE, CINHAL, and reference lists of identified articles, without language restrictions, in August 2010. RESULTS: Population studies suggest that there is an increased risk of TE in children with IBD compared to controls. TE occurred in children with IBD in all age ranges, mostly (82.8%) during active disease, and more frequently in children with ulcerative colitis (odds ratio [OR] 3.7, 95% confidence interval [CI] 1.8-7.6). At least one specific risk factor for TE was recognized in 50% of cases; two risk factors were present in 24%. Out of 92 published cases of TE in children with IBD, 54.3% occurred in cerebral site, 26% in the limbs, 13% in the abdominal vessels, and the remaining in the retina and lungs. After a first episode of TE, an early recurrence was observed in 11.4% of children, a late recurrence in 10%. A number of different therapeutic schemes were used. Overall mortality was 5.7% and was mostly associated with cerebral TE. CONCLUSIONS: Population studies are needed to clarify the risk of TE in children with IBD, the relative weight of other risk factors, the characteristics of the events, and to define guidelines of therapy and prophylaxis