Helicobacter pylori Eradication Rate Using Stool Antigen Test in Vietnamese Children: A Prospective Multicenter Study.

Objectives: This study assessed the diagnostic value of a monoclonal immunoassay stool antigen test (HpSA) for Helicobacter pylori (H. pylori) infection and the eradication outcomes. Methods: Children undergoing digestive endoscopy at 2 Children's Hospitals in Ho Chi Minh City were recruited. Treatment was offered to H. pylori-infected children. Stool samples were collected on the same day as the endoscopy procedure and after 6 weeks post-treatment for HpSA. Diagnostic value and optimal cutoff of HpSA were assessed using biopsy-based tests as the gold standard. Eradication was defined as a negative HpSA post-treatment. Ethical approval was obtained, and informed consent was signed by the participants. Results: In total, 394 patients participated in the study. The most common symptoms were epigastric pain (74.6%) and vomiting (37.3%). H. pylori status was positive in 78% of patients (306/394), doubtful in 10.1%, and negative in 12.2%. HpSA was positive in 73.2% (142/194). Excluding doubtful infections, the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of HpSA were 87.4%, 95.2%, 99.2%, 51.3%, and 88.4%, respectively. The optimal cutoff value of 0.148 provided similar accuracy to the recommended cutoff. The eradication rate was 56.1% in per-protocol analysis and 27.9% in intention-to-treat analysis. Treatment success was higher in boys, but lower among malnourished children and those infected with cagA+ strains. Conclusions: The HpSA is reliable for identifying H. pylori infection in epidemiological studies and assessing eradication outcomes. The low eradication rate highlights the need for an appropriate intervention strategy in Vietnamese children.

Antibiotic resistance and heteroresistance in Helicobacter pylori isolates from symptomatic Vietnamese children: A prospective multicenter study.

BACKGROUND: Antibiotic resistance of Helicobacter pylori (H. pylori) is increasing worldwide, with geographical variations, impacting the treatment outcomes. This study assessed the antibiotic resistance patterns of H. pylori in Vietnamese children. MATERIALS AND METHODS: Symptomatic children undergoing gastroduodenoscopy at two tertiary Children's Hospitals in Ho Chi Minh City were recruited. Antral and corpus biopsies were obtained and cultured separately. Susceptibility to amoxicillin (AMO), clarithromycin (CLA), metronidazole (MET), levofloxacin (LEV), and tetracycline (TET) was determined using E-test. Polymerase chain reaction was performed on another antral biopsy to detect the urease gene, cytotoxin-associated gene A (cagA), vacuolating cytotoxin A (vacA) genotypes, and 23S rRNA mutations conferring CLA resistance. RESULTS: Among 123 enrolled children, a high primary resistance rate was found for CLA (68.5%, 61/89), followed by LEV (55.1%), MET (31.5%), AMO (25.8%), and TET (1.1%). Secondary resistance rates were 82.1% (7/28), 71.4%, 53.6%, and 3.6% for CLA, LEV, MET, and TET, respectively. Multidrug resistance was frequent (67.7%), with common patterns including CLA + LEV (20.3%) and CLA + MTZ + LEV (15.2%). Heteroresistance was detected in eight children (6.5%). The A2143G mutation was detected in 97.5% (119/122) of children. 86.1% of children had positive cagA strains and 27.9% had multiple vacA genotypes. No factor was significantly associated with antibiotic resistance. CONCLUSIONS: The alarming rate of antibiotic resistance for H. pylori, especially for CLA, with emerging multi- and hetero-resistant strains, pose a major treatment challenge that precludes CLA use as empirical therapy. Biopsies from both antrum and corpus can improve H. pylori culture, allowing tailored treatment based on antimicrobial susceptibility.

Helicobacter pylori Infection and Peptic Ulcer Disease in Symptomatic Children in Southern Vietnam: A Prospective Multicenter Study.

BACKGROUND: Helicobacter pylori (H. pylori) remains a major cause of gastroduodenal diseases. We aimed to evaluate the burden of this infection, particularly peptic ulcer disease in Vietnamese children. METHODS: We enrolled consecutive children referred for esophagogastroduodenoscopy at two tertiary children's hospitals in Ho Chi Minh City, from October 2019 to May 2021. Children treated with proton pump inhibitors during the last two weeks or antibiotics for four weeks, and those having a previous or interventional endoscopy were excluded. H. pylori infection was diagnosed with either a positive culture or positive histopathology combined with a rapid urease test, or with a polymerase chain reaction of the urease gene. The study was approved by the Ethics Committee and written informed consent/assent was obtained. RESULTS: Among 336 enrolled children aged 4-16 (mean: 9.1 ± 2.4 years; 55.4% girls), H. pylori infection was positive in 80%. Peptic ulcers were detected in 65 (19%), increasing with age, and 25% with anemia. cagA+ strains were detected at a higher rate in children with ulcers. CONCLUSIONS: Prevalence of H. pylori and peptic ulcers is high among symptomatic Vietnamese children. It is crucial to have a program for early detection of H. pylori to reduce ulcer risk and gastric cancer later.

Factors Associated With Helicobacter Pylori Infection Among School-Aged Children From a High Prevalence Area in Vietnam.

Objectives: The study aimed to identify prevalence of H. pylori infection and associated risk factors among pupils of Ho Chi Minh city (HCMC). Methods: A total of 1,476 pupils aged 6-15 years were enrolled in this cross-sectional study using multiple-stage sampling method. Infection status was assessed using stool antigen-test. A questionnaire was used to obtain socio-demographic, behavioral, and environmental factors. Logistic regression was performed to assess possible factors related to the infection. Results: Of the 1,409 children included in the analysis, 49.2% were male and 95.8% were of Kinh ethnicity. About 43.5% of parents completed college or university. The overall prevalence of H. pylori was 87.7%. Infrequency of handwashing with soap after toilet, the use of only water to clean after toilet, crowded living areas, larger family size, and younger age were independently contributing to an increased prevalence of H. pylori. Conclusion: H. pylori infection is highly prevalent in HCMC, and is associated with poor hygienic practices, crowded living areas, larger family size, and younger age. These findings highlight the importance of fecal-oral route and the attribution of crowded living conditions to the spreading of H. pylori in HCMC. Therefore, preventive programs should be set up with a focus on education of hygiene practices, and oriented to those living in crowded conditions.

High Prevalence of Helicobacter pylori Infection Among School-Aged Children in Ho Chi Minh City, VietNam.

Objectives: There is no study on Helicobacter pylori (H. pylori) infection in pupils of Ho Chi Minh city (HCMC), the most overcrowded city in Vietnam. Therefore, the aim of this study was to estimate the prevalence of H. pylori and its geographical spread among school-aged children. Methods: A school-based cross-sectional study was conducted among 1854 pupils across 24 districts of HCMC in 2019. Multiple-stage sampling method was used to enroll pupils. We built a four-points index for geographical division based on population density and employees density to evaluate the link between H. pylori and crowded level. Stool samples were analyzed by monoclonal enzyme-immunoassay stool antigen-test to assess the infection status. Logistic regression was performed to assess possible factors related to H. pylori infection. Results: The overall prevalence of H. pylori was 87.7%. There was a linear increasing trend in the infection rate (p < 0.001) across the 4-points index of HCMC and this trend maintained within both age and gender subgroups (p = 0.02). Conclusion: Prevalence of H. pylori was high and it increased with population density or employees density. Therefore, it is crucial to plan and implement the reduction of H. pylori infection programs by targeting the highly concentrated population areas of HCMC.

Collagen XI Alpha 1 (COL11A1) Expression in the Tumor Microenvironment Drives Neuroblastoma Dissemination.

BACKGROUND: Neuroblastoma (NB) is among the most common cancers in children. A highly aggressive form of cancer, NB relies on cells in the microenvironment for dissemination particularly cancer associated fibroblast (CAFs). CAFs synthesise the extracellular matrix to create a scaffold for tumor growth thus enabling the carcinogenesis of NB, Collagen, an abundant scaffold protein produced by CAFs, has been implicated in the creation of an optimal tumor microenvironment, however, the expression profile of collagen within NB is not yet known. METHODS: We characterised collagen expression within the tumor-stroma boundary by microarray and confirmed by qRT-PCR and immunohistochemistry. RESULTS: The collagen marker, COL11A1, was also upregulated in NB CD45+ cells and SMA+ CAFs. Furthermore, SMA+ CAFs led to neuroblastoma cell invasion in an in vitro co-culture system which was subsequently attenuated by gene silencing COL11A1. Immunohistochemical staining of clinical tumor samples revealed that high COL11A1 expression in the stroma adjacent to tumour site, significantly associated with advanced cancer stages, age ≥18 months, undifferentiated tumor status, relapse and poor overall survival. CONCLUSION: Collectively, these results suggest that a COL11A1 signature in the NB microenvironment could represent a novel target for therapeutic intervention.

ARID1A-SIN3A drives retinoic acid-induced neuroblastoma differentiation by transcriptional repression of TERT.

Aggressive, high-risk neuroblastoma (NB) exhibits an immature differentiation state, profound epigenetic dysregulation and high telomerase activity. It has been suggested that aggressive NB may be treatable by inducing differentiation whereas therapeutic targeting of telomerase is under investigation for multiple cancer types. While epigenetic regulation of the telomerase reverse transcriptase (TERT) promoter has been described in high-risk NB, the exact molecular mechanisms are still not completely understood. Here we used quantitative real-time polymerase chain reaction (PCR), chromatin immunoprecipitation qPCR, quantitative telomeric repeat amplification protocol, and immunoblot techniques to investigate epigenetic regulation of TERT in wild-type and genetically modified NB cell lines. We demonstrated that TERT expression is reduced during 13-cis retinoic acid-induced NB differentiation and that this inversely correlated with increased expression of AT-rich interaction domain 1A (ARID1A), a subunit of the SWItch/sucrose nonfermentable chromatin remodeling complex. We showed that ARID1A directly caused suppression of TERT and was reliant on DNA binding and co-occupancy of the TERT promoter by the SIN3 transcription regulator family member A (SIN3A) repressor complex allowing NB differentiation to proceed. Finally, using data from NB patient cohorts, we reported a significant correlation between low ARID1A expression, elevated expression of TERT, and poorly differentiated, high-risk NB. These results provide insights into a key epigenetic pathway responsible for modulating TERT-driven NB progression, which could represent a target for therapeutic intervention.

Long-Term Outcomes and Quality of Life in Patients after Soave Pull-Through Operation for Hirschsprung's Disease: An Observational Retrospective Study.

INTRODUCTION: Patients after pull-through operation for Hirschsprung's disease (HD) are at high risk of defecation disorders. This study aimed at investigating their long-term outcomes and quality of life (QoL) in comparison with controls. PATIENTS AND METHODS: Patients older than 5 years operated on for HD were interviewed to complete detailed questionnaires on bowel function. Patients without neurologic impairment were enrolled in a QoL survey to compare with controls matched for sex and age and selected randomly from the general population using sampling set in a ratio of four controls to one case of HD. RESULTS: In total, 53 operated patients were enrolled. Mean age of the patients was 16 ± 8 years, with 68% boys. Rectosigmoid aganglionosis was the most seen form of HD in 38 (72%) cases. Open Soave was performed in 40 (75.5%) cases, and minimally invasive surgery Soave (MIS Soave) in 13 (24.5%) cases. At investigation, prevalence of fecal incontinence and constipation were 22.6 and 13.2%, respectively. Regarding QoL survey, 45 patients and 180 controls were enrolled, excluding 8 patients with neurologic impairment. Thirty-seven (82.2%) patients were classified as having a good QoL (score ≥ 9 points); whereas six had a fair QoL (5-8 points) and two had a poor QoL (< 5 points). QoL score in the cases and the controls were 10.2 ± 2.5 and 11.9 ± 0.4 points, respectively. Long aganglionosis form of HD was significantly associated with a low QoL (score < 8 points), adjusted odds ratio = 9, 95% confidence interval [1.3; 64.1] (p < 0.05). In subscales analyses, the prevalence of each dimension including fecal continence, school absenteeism, unhappiness or anxiety, food restriction, and peer rejection was significantly higher in operated patients than in controls (p <0.001). CONCLUSION: Although the QoL of patients operated on for HD in general was with good outcomes, fecal incontinence and constipation still are problematic issues and challenges in a high percentage of patients. Therefore, a long-term and multidisciplinary follow-up is essentially required for these patients.

Rectal suction biopsy with calretinin immunohistochemistry in patients suspected with residual aganglionosis after operation for Hirschsprung disease.

INTRODUCTION: This study investigates the use of rectal suction biopsy (RSB) with calretinin immunohistochemical staining (CIS) in patients suspected of having abnormally innervated bowel after pull through operation for Hirschsprung disease (HD). METHOD: This study was conducted in Children's Hospital 2, Ho Chi Minh City from January 2015 through June 2016. Patients suspected with abnormally innervated bowel after pull through operation for HD were submitted for a RSB with CIS. Following histological results, the patients underwent an appropriate treatment (redo pull through operation or non-operative medical management) and followed up at least 6 months to evaluate their outcomes. RESULTS: Ten patients were enrolled in our study. The median age was 5.6 (range 1.4-20) years. The diagnosis of normally innervated bowel was made in five patients by showing positive reactivity of CIS on RSB, whereas five others were diagnosed with abnormally innervated bowel. Final diagnosis of the five latter patients was confirmed by analyses of the resected bowel after a redo pull through operation (including 4 cases with residual aganglionosis and one case with transition zone bowel). CONCLUSIONS: RSB with CIS is a reliable and simple method for diagnosis of abnormally innervated bowel after pull through operation for HD. LEVEL OF EVIDENCE: III TYPE OF STUDY: Study of diagnostic test (evaluate the effectiveness of a diagnostic test or outcome assessment).

Diagnostic value of rectal suction biopsies using calretinin immunohistochemical staining in Hirschsprung's disease.

BACKGROUND: The study investigates the diagnostic value of calretinin immunohistochemical staining (CIS) on rectal suction biopsies (RSB) in Hirschsprung's disease (HD). METHODS: A prospective study was conducted at Children's Hospital 2 in Ho Chi Minh City, Vietnam, from January through December 2015. Patients suspected of HD during this period underwent RSB and were followed in order to assess the accuracy of the diagnostic test with CIS compared with conventional histology (H&E). RESULTS: A total of 188 children with RSB were investigated. Median age was 7.1 (range 0.2-159) months with 65.4% boys. HD was confirmed in 80 (42.6%) children. There were 1 false positive and no false-negative cases. The sensitivity and specificity were 100% (80/80) and 99.1% (107/108) for CIS and 100% and 85.2% for H&E, respectively. Cohen's kappa coefficient was 0.9891 with a diagnostic accuracy of 99.5% for CIS, compared with 0.8303 and 91.5% for H&E, respectively. There were no serious complications related to the RSB. CONCLUSION: RSB with CIS is a useful diagnostic method for HD, with easy interpretation and no need for cryostat. CIS has a high diagnostic accuracy and should be considered as the primary method for the diagnosis of HD by RSB. LEVEL OF EVIDENCE: Diagnostic Studies - Level I.

Current status and actual need for pediatric liver transplantation in Southern Vietnam.

Liver transplantation (LT) has considerably improved the outcome of patients with end-stage liver disease, especially in children. The first pediatric LT in Vietnam was performed in 2004. To assess the current need for pediatric LT in Southern Vietnam, a total of 280 patients with chronic liver disease followed at Children's Hospital 2 (Ho Chi Minh City), the only pediatric LT center in this region, were evaluated from January 2009 to June 2014. Sixty-seven patients satisfied criteria for LT but only one transplant surgery occurred since 2009. Parental consent for LT was obtained only in 28.4% of patients. The main reasons for the small number of LTs were financial costs, far distance from home, lifelong follow-up and treatment, and shortage of organ donors. We conclude that the current need for pediatric LT in Southern Vietnam is high. Efforts should be made to develop the liver transplant program in this developing country.

The immunological monitoring of kidney and liver transplants in adult and pediatric recipients.

Over the last half century, kidney and liver transplantation have been recognized as the treatment of choice for adult and children with end-stage renal or liver failure. Infants present a relative naïve immune system, but they are capable of mounting both cellular and humoral immune responses to the foreign antigens presented by the allograft. Immune monitoring is a way of measuring functional and molecular correlates of immune reactivity which may provide clinically useful information for identifying patients who have an increase risk of acute rejection prior to clinical symptoms or develop transplant tolerance. However, although numerous assays have been shown to predict rejection, to date no assays have been demonstrated to detect or predict transplantation tolerance. This is a summary of the published literature on promising antigen-specific and non-antigen-specific assays used for immunological monitoring in solid organ transplantation. This work also attempts to review their applicability to pediatric transplantation, specifically, pediatric kidney and liver recipients.

Pre- and post-transplant monitoring of granzyme B enzyme-linked immunosorbent spot assay in pediatric liver recipients.

UNLABELLED: This study aims to investigate potential role of granzyme B enzyme-linked immunosorbent spot (GrB ELISPOT) for immunological monitoring in pediatric liver transplantation. PATIENTS AND METHODS: Peripheral blood mononuclear cells from 28 pediatric recipients were serially tested for GrB-producing donor-reactive cells at day 0 pre-transplantation (baseline) and days 7, 14, and 28 post-transplantation. RESULTS: At baseline, no difference of GrB value was found in acute rejection (14/28) compared to normal graft function patients (day 0: 4(3.9) spots versus 5(2.9) spots, respectively: p=0.65). At day 7 post-transplantation, acute rejection patients showed frequencies of GrB ELISPOT higher than those with normal graft function, but the differences observed were not statistically significant (day 7: 15(4.9) spots versus 10(4.0) spots, respectively: p=0.55). GrB increased significantly at day 7 from baseline in the rejection group (15(4.9) spots versus 4(3.9), respectively p=0.04), whereas corresponding changes were not significant in the group without rejection (10(4.0) versus 5(2.9), respectively: p=0.15). CONCLUSION: GrB ELISPOT pre-transplantation could not predict the occurrence of early post-transplant acute rejection; similarly frequencies at days 7, 14 and 28 could not be correlated with acute rejection in pediatric liver recipients. However, a kinetic study of GrB ELISPOT could be helpful to predict or confirm early rejection in the small group of liver allograft recipients analyzed in this study.

Immunological monitoring after organ transplantation: potential role of soluble CD30 blood level measurement.

Analysing the relevance of soluble CD30 (sCD30) in the bloodstream before and after transplantation may be important for the monitoring of transplant recipients. In this study, 27 patients (15 pediatric liver and 12 adult kidney graft recipients) were investigated. In the liver graft group, the patients who developed acute rejection during the first month (n=9) had a slightly higher sCD30 value on pre-transplantation baseline (day 0) and post-transplantation day 7, when compared to patients with normal graft function (n=6) (day 0: 102(1.6) U/ml versus 118(1.5) U/ml, p=0.52) and (day 7: 69(1.5) U/ml versus 83(1.6) U/ml, p=0.47). Increased serum sCD30 was shown to correlate with increased interleukin-10 circulating levels between day 0 and day 7 (r=0.53; p=0.04), whereas, no correlation could be evidenced between interferon-gamma (IFN-gamma) and sCD30 (r=0.02; p=0.47). Similarly, in the kidney transplantation group, no significant difference was found in sCD30 levels at day 0 in both groups with graft rejection or normal graft function (n=6) (85(1.3) U/ml versus 77(1.6) U/ml, p=0.66), but sCD30 decreased significantly at day 7 post-transplantation from baseline value in the rejection group (n=6) (77(1.6) versus 35(1.4); p=0.02). We conclude that increased serum sCD30 was correlated with increased IL-10 (interleukin-10) circulating levels, but not with IFN-gamma levels in the post-transplantation period. Neither pre-transplantation sCD30 nor sCD30 at day 7 post-transplantation could be correlated with acute rejection in liver graft recipient. The monitoring of sCD30 might constitute a tool to assess the risk of acute rejection in renal transplant but did not appear as a valuable mean for early immunological monitoring in the small group of liver allograft recipients patients analysed in this study.

Monitoring tolerance after human liver transplantation.

The validation of reliable, non-invasive immunological assays evaluating anti-donor responsiveness in allograft recipients would provide a clinically relevant tool for the early detection of ongoing rejection process as well as for the identification of operational tolerance in the long term. A sequential approach towards immunological monitoring of allografts is proposed in this review: (i) investigations exploring the initial donor-recipient alloresponses, including the analysis of the cytokine network; (ii) investigations regarding graft acceptance and operational tolerance in long-term transplant patients, consisting in the analysis of regulatory T cells and of circulating precursors of dendritic cells, in the measurement of T cell alloreactivity as well as in the study of T cell receptor repertoires. Beside the conventional in vivo and in vitro immunological techniques, the potential applications of molecular imaging in transplantation also deserve further exploration, with particular respect to allograft immune monitoring. Enforced collaboration between transplant clinicians and immunologists will be required to develop the translational research protocols required for the development of immunological monitoring, within an international multicentric network.

Early immunological monitoring after pediatric liver transplantation: cytokine immune deviation and graft acceptance in 40 recipients.

Cytokine deviation may be a factor contributing to graft acceptance. We analyze, in the context of liver transplantation, circulating cytokine levels and their mRNA precursors in liver biopsy samples to study a putative correlation with early immunologic outcome. Forty primary pediatric liver recipients were submitted to a prospective immune monitoring protocol, including 8 of 40 patients with an early, biopsy-proven acute rejection episode. The 32 patients with graft acceptance showed markedly increased interleukin (IL)-10 blood levels at 2 hours after reperfusion on days 1 and 4 after transplantation as compared with baseline, whereas patients with graft rejection only exhibited increased IL-10 levels at 2 hours. A good correlation was observed between IL-10 peripheral levels and levels ascertained by IL-10 reverse transcriptase-polymerase chain reaction at 2 hours and on day 7. Patients with graft acceptance also showed a decrease in interferon gamma (IFN-gamma) at 1 and 2 hours after reperfusion on days 1, 4, 7, 14, and 28 after transplantation. One patient with graft tolerance who had subsequent immunosuppression withdrawal after posttransplantation lymphoproliferative disease showed a similar intraoperative IL-10 pattern, whereas posttransplantation tumor necrosis factor alpha and IFN-gamma levels greatly decreased. The occurrence of cytokine immune deviation may therefore be related to early graft acceptance in children who receive liver transplants.

The immunological monitoring of alloreactive responses in liver transplant recipients: a review.

The aim of this work is to review the current knowledge in the field of immunological monitoring of allogenic responsiveness in clinical liver transplantation. When compared to other solid-organ transplants, liver allografts are considered as immunologically privileged, and, accordingly, constitute a favorable setting to develop experimental as well as clinical strategies for minimization of immunosuppression and even induction of operational tolerance. The validation of simple, reliable, noninvasive assays exploring antidonor alloreactivity will constitute a crucial step toward implementing such approaches in the clinic. In contrast to research in rodents claiming the development of donor-specific tolerance in case of graft survivals of over 100 days without immunosuppression, it is impractical to confirm tolerance induction in this way in humans. Promising candidate assays include the detection of post-transplant immune deviation, of circulating precursors of dendritic cells subtypes, and of regulatory T cells. A conceptual framework for the development of tolerance assays in clinical liver transplantation is also proposed.