Successful treatment with tofacitinib for anti-melanoma differentiation-associated gene 5 antibody-positive juvenile dermatomyositis: case reports and review of the literature.

Although the clinical efficacy of tofacitinib has been reported in adult patients with anti-melanoma differentiation-associated gene 5 (MDA5) antibody-positive (Ab+) dermatomyositis, data on its use in refractory juvenile dermatomyositis (JDM) are scarce. We describe two female Japanese patients with anti-MDA5 Ab + JDM and rapidly progressive interstitial lung disease who achieved remission by adding tofacitinib to existing immunosuppressive drugs and present a literature review. While both patients received various immunosuppressive or anti-inflammatory treatments for induction therapy, remission could not be achieved. Subsequently, tofacitinib was administered to reduce the Krebs von den Lungen-6 level 5 months after diagnosis in one patient; the other patient received tofacitinib 4 months after diagnosis to reduce ferritin levels and skin manifestations. Subsequently, both patients achieved remission, and prednisolone was withdrawn. Tofacitinib reduced the interferon signature associated with dermatomyositis/JDM disease progression and exerted a therapeutic effect on dermatomyositis/JDM. We found six published cases from five articles of tofacitinib for refractory anti-MDA5 Ab + JDM. Except for one case of herpes simplex meningitis, the other cases, including ours, had improved disease activity without severe adverse events, and steroids and immunosuppressive medicines could be tapered. Tofacitinib could be considered an available therapy for refractory anti-MDA5 Ab + JDM.

Differentiation of Active Ulcerative Colitis vs Noninflammatory Bowel Disease Proctitis by Transperineal Superb Microvascular Imaging.

BACKGROUND: Transabdominal ultrasonography and transperineal ultrasonography (TPUS) appear correspond to colonoscopy (CS) for evaluating ulcerative colitis (UC) activity, but their utility in UC diagnosis remains unclear. This research compared the accuracy of TPUS and CS for assessing rectal activity and differentiating noninflammatory bowel disease proctitis from UC in pediatric cases. METHODS: The study is a blinded, prospective, and controlled trial. Prospectively, values of fecal calprotectin (FCP) and findings of the TPUS and CS were compared between child cases of UC and non-IBD proctitis. Findings of rectal wall thickening (RWT), rectal wall flow (RWF) on power Doppler, and microvascular signal at wall circumference (MSWC) on monochrome superb microvascular imaging assessed using TPUS were compared with the CS. RESULTS: Thirty patients with Mayo endoscopic subscore (MES) 0 to 1 UC, 57 with MES 2 to 3 UC, and 44 with proctitis were registered. Fecal calprotectin, RWF, and MSWC indicated significant differences among the groups (P < .05). Rectal wall thickening showed no significant difference between MES 0-1 and proctitis (P = .76). Rectal wall thickening and MSWC were independent predictors of endoscopic activity of UC, resulting in a sensitivity and specificity of 100% for RWT ≥4.5 mm and positive MSWC. Fecal calprotectin and RWF were independent predictors for differentiating MES 0 to 1 and proctitis, and FCP and RWT were independent predictors for differentiating MES 2 to 3 and proctitis. Sensitivity and specificity were 77.2% and 80.9%, respectively, for FCP >242.5 µg/g and RWF negative; and they were both 100% for RWT >4.1 mm and MSWC positive. CONCLUSIONS: Transperineal ultrasonography with mSMI may enable the evaluation of rectal activity and differentiation of UC from non-IBD proctitis with accuracy comparable to endoscopy.

Transperineal ultrasonography with superb microvascular imaging can differentiate ulcerative colitis from noninflammatory bowel disease proctitis and is therefore useful in distinguishing whether diarrhea and bloody stool during the treatments of ulcerative colitis are due to recurrence or infection.

Attenuated Expression of SLCO2A1 Caused by DNA Methylation in Pediatric Inflammatory Bowel Disease.

BACKGROUND: SLCO2A1 encodes a prostaglandin (PG) transporter, and autosomal recessive pathogenic variants of this gene cause chronic enteropathy associated with SLCO2A1. It is unclear whether a heterozygous pathogenic variant of SLCO2A1 has a role in the pathogenesis of other types of inflammatory bowel disease (IBD). In this study, we investigated the possible involvement of a local epigenetic alteration in SLCO2A1 in patients with a heterozygous pathogenic variant. METHODS: We conducted whole-exome sequencing of samples from 2 sisters with suspected monogenic IBD. In addition, we performed bisulfite sequencing using DNA extracted from their small and large intestine samples to explore epigenetic alterations. RESULTS: A heterozygous splicing site variant, SLCO2A1:c.940 + 1G > A, was detected in both patients. To explore the possible involvement of epigenetic alterations, we analyzed protein and messenger RNA expression of SLCO2A1, and observed attenuated SLCO2A1 expression in the inflamed lesions of these patients compared with that in the control individuals. Furthermore, bisulfite sequencing indicated dense methylation in the promoter region of SLCO2A1 only in the inflamed lesions of both patients. The urinary PG metabolite levels in these patients were comparable to those in patients with chronic enteropathy associated with SLCO2A1 and higher than those in the control individuals. We found considerably higher levels of the metabolites in patient 1, who showed more severe symptoms than patient 2. CONCLUSIONS: Local DNA methylation attenuated SLCO2A1 expression, which may evoke local inflammation of the mucosa by the unincorporated PG. These findings may improve our understanding of the epigenetic mechanisms underlying IBD development.

We observed attenuated expression of SLCO2A1 caused by DNA methylation in inflamed lesions of patients with suspected monogenic inflammatory bowel disease. This finding prompted us to understand the important roles of genetic and epigenetic alterations in the development of inflammatory bowel disease.

Clinical Guidelines for Diagnosis and Management of Juvenile Polyposis Syndrome in Children and Adults-Secondary Publication.

Juvenile polyposis syndrome (JPS) is a rare disease characterized by multiple hamartomatous polyps within the gastrointestinal tract. SMAD4 or BMPR1A is known as a causative gene of JPS. Approximately 75% of newly diagnosed cases have an autosomal-dominantly inherited condition, whereas 25% are sporadic without previous history of polyposis in the family pedigree. Some patients with JPS develop gastrointestinal lesions in childhood and require continuous medical care until adulthood. JPS is classified into three categories according to phenotypic features of polyp distributions, including generalized juvenile polyposis, juvenile polyposis coli, and juvenile polyposis of the stomach. Juvenile polyposis of the stomach is caused by germline pathogenic variants of SMAD4 with a high risk leading to gastric cancer. Pathogenic variants of SMAD4 are also associated with hereditary hemorrhagic telangiectasia-JPS complex, inducing regular cardiovascular survey. Despite growing concerns regarding the managing JPS in Japan, there are no practical guidelines. To address this situation, the guideline committee was organized by the Research Group on Rare and Intractable Diseases granted by the Ministry of Health, Labor and Welfare involving specialists from multiple academic societies. The present clinical guidelines explain the principles in the diagnosis and management of JPS with three clinical questions and corresponding recommendations based on a careful review of the evidence and involve incorporating the concept of the Grading of Recommendations, Assessment, Development, and Evaluation system. Herein, we present the clinical practice guidelines of JPS to promote seamless implementation of accurate diagnosis and appropriate management of pediatric, adolescent, and adult patients with JPS.

Eosinophilic enteritis requiring differentiation from chronic enteropathy associated with SLCO2A1 gene: A case report.

BACKGROUND: Eosinophilic gastrointestinal disease (EGID) is a disorder characterized by infiltration of eosinophils causing mucosal damage and dysfunction of the gastrointestinal tract. The endoscopic findings of eosinophilic enteritis (EoN), an EGID variant, are nonspecific and occasionally difficult to diagnose. In contrast, chronic enteropathy associated with SLCO2A1 (CEAS) is a chronic persistent small intestinal disorder characterized by endoscopic findings such as multiple oblique and circular ulcers. CASE SUMMARY: We report the case of a 10-year-old boy who had suffered abdominal pain and fatigue for the preceding 6 mo. He was referred to our institute for investigation of suspected gastrointestinal bleeding because of severe anemia with hypoproteinemia and positive fecal human hemoglobin. The upper and lower gastrointestinal endoscopic findings were normal; however, double-balloon small bowel endoscopy showed multiple oblique and circular ulcers with discrete margins and mild constriction of the intestinal lumen in the ileum. The findings were highly consistent with CEAS, but urine prostaglandin metabolites were within normal limits, and no previously reported mutations in the SLCO2A1 gene were identified. Histological evaluation demonstrated moderate to severe eosinophilic infiltration localized to the small intestine suggesting a diagnosis of EoN. Clinical remission was maintained with montelukast and a partial elemental diet, but emergent surgery for bowel obstruction due to small intestinal stenosis was performed two years after the initial treatment. CONCLUSION: EoN should be considered in the differential diagnosis of CEAS-like small intestinal ulcerative lesions and normal urinary prostaglandin metabolite levels.

Novel Findings of Early Cardiac Dysfunction in Patients With Childhood-Onset Inflammatory Bowel Disease Using Layer-Specific Strain Analysis.

BACKGROUND: Patients with inflammatory bowel disease (IBD) are at a higher risk of developing cardiovascular diseases than healthy individuals, owing to persistent chronic inflammation and treatment effects. This study aimed to assess left ventricular function in patients with childhood-onset IBD using layer-specific strain analysis and to identify early indicators of cardiac dysfunction in them. METHODS: A total of 47 patients with childhood-onset ulcerative colitis (UC), 20 patients with Crohn's disease (CD), and 75 age- and sex-matched healthy control subjects were included in this study. Conventional echocardiographic measurements of layer-specific (ie, endocardium, midmyocardium, and epicardium) global longitudinal strain and global circumferential strain (GCS) were evaluated in these participants. RESULTS: Layer-specific strain analysis showed that global longitudinal strain was lower in all layers for the UC (P < .001) and CD (P < .001) groups, regardless of the age at onset, but that GCS was only lower in the midmyocardial (P = .032) and epicardial (P = .018) layers in the CD group than in the control group. Although the mean left ventricular wall thickness was not significantly different among the groups, it was significantly correlated with the GCS of the endocardial layer in the CD group (ρ= -0.615; P = .004), suggesting that thickening of the left ventricular wall occurred as a compensatory mechanism to maintain the endocardial strain in the CD group layer. CONCLUSIONS: Children and young adults with childhood-onset IBD displayed decreased midmyocardial deformation. Layer-specific strain could also be useful to identify indicators of cardiac dysfunction in patients with IBD.

Patients with inflammatory bowel disease are at a higher risk of developing cardiovascular disease than healthy individuals. Our study revealed that children and young adults with childhood-onset inflammatory bowel disease already have reduced myocardial deformability.

Accuracy of Transperineal Ultrasonography for Assessing Rectal Lesions in Paediatric Ulcerative Colitis: A Prospective Study.

BACKGROUND AND AIMS: Transabdominal ultrasonography [TAUS] appears comparable to colonoscopy for evaluating ulcerative colitis [UC] activity, but it has low accuracy in rectal evaluation. In this study, the accuracy of transperineal ultrasonography [TPUS] for evaluating rectal activity was compared to that of colonoscopy in paediatric UC cases. METHODS: Faecal calprotectin [FCP] values and TPUS and colonoscopic findings were compared prospectively in paediatric UC cases. Rectal wall thickening [RWT] and rectal wall flow [RWF] on power Doppler evaluated by TPUS were compared with the colonoscopy findings and were also measured on TAUS and assessed for the concordance rate of each finding. RESULTS: Thirty Mayo endoscopic sub-score [MES] 0-1 UC cases and 57 MES 2-3 UC cases were enrolled. FCP, RWT and RWF showed significant differences between the two groups [p < 0.05]. RWT and RWF were independent predictors of UC endoscopic activity, showing sensitivity of 95.8% and specificity of 100% with RWT ≥ 4.5 mm and positive RWF. The concordance rates between TPUS and TAUS findings in MES 2-3 were moderate to fair, whereas those in MES 0-1 were fair to poor. The concordance rates between ultrasonic examiners were good for both TAUS and TPUS. CONCLUSIONS: TPUS may evaluate rectal activity of UC with accuracy comparable to endoscopy. If accurate ultrasonic screening for the total colon can be performed by TPUS and TAUS, repeated evaluation of short-term treatment response may be possible.

An Isolated Intestinal Juvenile Polyp Diagnosed by Abdominal Ultrasonography and Resected by Double-Balloon Endoscopy: A Case Report and Literature Review.

Juvenile polyps, typically localized in the rectum and sigmoid colon, are a common cause of pediatric bloody stool. An isolated small intestinal juvenile polyp is uncommon and generally difficult to diagnose. The first case of an isolated juvenile polyp diagnosed by abdominal ultrasonography before acute abdomen had developed and resected by double-balloon endoscopy is presented along with a review of previous reports including this case. A two-year-old Japanese boy was referred to our institute for further evaluation of anemia persisting from one year of age. Laboratory findings showed mild iron deficiency anemia and elevated fecal human hemoglobin (Hb) and fecal calprotectin values. Upper and lower endoscopic findings showed no abnormalities. Because the abdominal ultrasonography performed one year later demonstrated a 15 mm jejunal polyp, combined with a similar finding on small intestinal capsule endoscopy, this was diagnosed as an isolated lesion. The lesion was resected by cautery with double-balloon endoscopy and diagnosed as a juvenile polyp pathologically. All clinical symptoms disappeared, and all laboratory data improved after treatment, without recurrence for more than one year after the procedure. Abdominal ultrasonographic screening and the fecal calprotectin value led to the diagnosis and non-surgical invasive treatment of an isolated small intestinal juvenile polyp.

Expert consensus on vaccination in patients with inflammatory bowel disease in Japan.

Immunosuppressive therapies can affect the immune response to or safety of vaccination in patients with inflammatory bowel disease (IBD). The appropriateness of vaccination should be assessed prior to the initiation of IBD treatment because patients with IBD frequently undergo continuous treatment with immunosuppressive drugs. This consensus was developed to support the decision-making process regarding appropriate vaccination for pediatric and adult patients with IBD and physicians by providing critical information according to the published literature and expert consensus about vaccine-preventable diseases (VPDs) [excluding cervical cancer and coronavirus disease 2019 (COVID-19)] in Japan. This consensus includes 19 important clinical questions (CQs) on the following 4 topics: VPDs (6 CQs), live attenuated vaccines (2 CQs), inactivated vaccines (6 CQs), and vaccination for pregnancy, childbirth, and breastfeeding (5 CQs). These topics and CQs were selected under unified consensus by the members of a committee on intractable diseases with support by a Health and Labour Sciences Research Grant. Physicians should provide necessary information on VPDs to their patients with IBD and carefully manage these patients' IBD if various risk factors for the development or worsening of VPDs are present. This consensus will facilitate informed and shared decision-making in daily IBD clinical practice.

A Pediatric Case of Inverted Meckel's Diverticulum Presenting with Cyclic Vomiting-like Symptoms: A Case Report and Literature Review.

Asymptomatic Meckel's diverticulum cases are not uncommon, leading to diagnostic difficulties in cases of atypical presentations with only gastrointestinal symptoms other than bloody stool. A nine-year-old boy diagnosed as having cyclic vomiting because of recurrent abdominal pain and vomiting for 6 months was referred to our institute and hospitalized due to worsening symptoms. After admission, abdominal ultrasonography showed the multiple concentric ring sign and a pseudokidney sign at the lower ileum, leading to the diagnosis of ileo-ileal intussusception, but the gastrointestinal symptoms and ultrasonic findings disappeared spontaneously. Transanal, double-balloon, intestinal endoscopy demonstrated a pedunculated polyp-like structure, and surgical resection was performed. An inverted diverticulum was found in the resected intestinal lumen, and ectopic gastric mucosa was identified histologically, leading to the diagnosis of inverted Meckel's diverticulum. In pediatric cases involving periodic attacks of vomiting and abdominal pain, unnecessary emergent surgery could be avoided by cautious imaging evaluation and consideration of ileo-ileal intussusception with advanced lesions of an inverted Meckel's diverticulum as a differential diagnosis, without facilely diagnosing cyclic vomiting. In addition, previous reports of inverted Meckel's diverticulum were reviewed, and the results were compared between adult and pediatric groups in each category.

Intestinal outcome of bone marrow transplantation for monogenic inflammatory bowel disease.

BACKGROUND: Some monogenic inflammatory bowel diseases (IBDs) are known to be refractory to conventional treatments. Although allogeneic hematopoietic stem-cell transplantation (allo-HSCT) has become a curative therapeutic option for certain monogenic IBDs, its effectiveness regarding endoscopic improvements has not been clarified. METHODS: The clinical course and endoscopic findings of patients with monogenic IBDs who were treated with allo-HSCT between December 2017 and November 2018 at the National Center for Child Health and Development, were retrospectively reviewed. The clinical disease activity was assessed using the weighted Pediatric Crohn's Disease Activity Index (wPCDAI) and the endoscopic finding was evaluated using the Simple Endoscopic Score for Crohn's Disease (SES-CD). Clinical remission was defined as a wPCDAI <10 and endoscopic remission was defined as an SES-CD of 2 or less. RESULTS: Four patients with severe monogenic IBDs, including three with X-linked inhibitors of apoptosis protein (XIAP) deficiency and one with interleukin-10 signaling defect, were treated with allo-HSCT with reduced-intensity conditioning. In four patients, the maximum scores of wPCDAI and SES-CD before allo-HSCT ranged from 67.5 to 120 and 20 to 34, respectively. After allo-HSCT, all four patients showed a significant improvement in intestinal inflammation and achieved both clinical and endoscopic remission. Although patients with XIAP deficiency presented with post-transplant hemophagocytic lymphohistiocytosis and a relatively late engraftment, all patients achieved prolonged clinical remission, and IBD medications were successfully discontinued in all patients. CONCLUSION: Allo-HSCT for monogenic IBD resulted in complete clinical resolution with endoscopically confirmed mucosal healing.

Expression of Oncogenic Molecules in Pediatric Ulcerative Colitis.

INTRODUCTION: Long-term disease duration of ulcerative colitis (UC) is known to increase the risk of developing colorectal cancer in adults; however, this association has not been genetically analyzed in children with UC. Herein, we examined the expression of cancer-related genes in the colonic mucosa of pediatric UC patients and their risk of developing colorectal cancer. METHODS: Microarray analysis of cancer-related gene expression was conducted on rectal mucosa biopsy specimens randomly selected from pediatric cases, including 4 active-phase UC cases, 3 remission-phase UC cases, and 3 irritable bowel syndrome control cases. The subject pool was then expanded to 10 active-phase cases, 10 remission-phase cases, and 10 controls, which were analyzed by real-time polymerase chain reaction (PCR) and immunohistochemical staining. RESULTS: The microarray results indicated significantly higher expression levels of cancer-related genes PIM2 and SPI1 in the active group than in the remission and control groups (p < 0.05). Real-time PCR confirmed that PIM2 and SPI1 expression levels were significantly higher, whereas TP53 and APC expression levels were significantly lower, in the active-phase group than in the remission and control groups (p < 0.05). Immunohistochemical staining for PIM2, SPI1, TP53, and APC proteins supported the real-time PCR results. CONCLUSIONS: Expression levels of previously unreported cancer-related genes in adult UC patients were significantly higher in pediatric UC patients than in controls. Inflammation of the gastrointestinal mucosa increased the expression levels of cancer-related genes even in childhood-onset UC cases, suggesting that chronic inflammation from childhood may increase the risk of colorectal cancer development.

Novel pediatric granulomatosis with polyangiitis with a marked bloody pericardial effusion and bloody stool: a case report.

BACKGROUND: Granulomatosis with polyangiitis (GPA) is a syndrome of refractory vasculitis involving the upper respiratory tract, lungs, kidneys, and systemic small and medium-sized arteries that affects all age groups. No pediatric case with a bloody pericardial effusion resulting in cardiac tamponade and co-existing hematochezia has been reported. CASE PRESENTATION: A 14-year-old boy was referred for evaluation of prolonged fever, chest pain, and intermittent hematochezia. Diagnostic imaging showed a prominent pericardial effusion. Immediately after admission, his systolic blood pressure decreased. Emergent pericardiocentesis resulted in aspiration of a massive amount of bloody pericardial fluid. This was diagnosed as cardiac tamponade because his blood pressure recovered immediately after the drainage. The patient had an elevated serine proteinase 3-anti-neutrophil cytoplasmic antibody (PR3-ANCA) level on serological examination. Head MRI showed thickening of nasal and sinusoidal mucosa and a cystic mass in the left sphenoid sinus. After ruling out malignancy based on the cytology of the effusion, chest MRI, and gallium scintigraphy, total colonoscopy showed multiple irregular-shaped aphthae from the right transverse colon to the cecum on the contralateral side of the mesenteric attachments. Biopsy specimens of aphthous lesions confirmed necrotizing granulomatous inflammation. A diagnosis of GPA was made based on these findings, and oral prednisolone (PSL) and azathioprine were started. The hematochezia disappeared rapidly, and no recurrence of pericardial effusion was seen after PSL tapering was completed. The PR3-ANCA level decreased into the normal range immediately after the initial therapy. CONCLUSIONS: Pericarditis is a common cardiac complication of GPA, but there have been no reports of resultant cardiac tamponade. This is the first case of pediatric GPA with cardiac and gastrointestinal complications preceding the common symptoms such as respiratory or renal symptoms. A case of pediatric GPA with hematochezia is also extremely rare. In conclusion, serial measurement of ANCA levels is important in patients with persistent fever and bloody stool, such as in inflammatory bowel disease, to make the diagnosis of a vasculitic syndrome.

Effectiveness of Biological Agents in the Treatment of Pediatric Patients with Crohn's Disease and Anal Fistulae.

INTRODUCTION: Anal fistulae have a significant impact on the quality of life of patients with Crohn's disease (CD). In this cross-sectional study, we aimed to determine whether biological agents were effective in treating anal fistulae in patients with CD. METHODS: Fifty-three patients diagnosed with CD were retrospectively enrolled. Their data regarding symptoms, treatments, and disease progression from January 2007 to December 2016 were reviewed from the medical records. Fifteen (28%) patients with CD were complicated by anal fistulae. RESULTS: The male-to-female ratio was 13:2, and the mean age at onset was 11 years and 6 months. Among the 15 patients, 14 (93%) had anal fistulae as an initial symptom. Almost all patients were treated by providing elemental diet, 5-aminosalicylic acid, and steroids as induction therapy. Biological agents were used in 8 patients (53.3%), and fistula closure was confirmed in all of them. Among the 7 patients not treated with biological agents, 1 (14.3%) had a recurrent anal fistula, while another had incomplete fistula closure. Regarding surgical management, 2 patients were treated using the seton method, and no patients required a colostomy. CONCLUSION: Treatment with biological agents is highly effective concerning the closure of anal fistulae in patients with CD, and reducing pain may improve their quality of life.

Eradication therapy for Helicobacter pylori infection based on the antimicrobial susceptibility test in children: A single-center study over 12 years.

BACKGROUND: Helicobacter pylori (H. pylori) infection causes chronic gastritis, duodenal and to a lesser extent, gastric ulcers, and gastric cancer. Most H. pylori infections are acquired in childhood, and effective treatment of childhood infection is very important. Esophagogastroduodenoscopy (EGD) is useful for endoscopic diagnosis, mucosal tissue biopsy, and culture examination for H. pylori in children and adults. In this paper, we report results of susceptibility tests and eradication rates in H. pylori-positive children who underwent EGD over a 12-year period. MATERIALS AND METHODS: The subjects were H. pylori-positive pediatric patients who had gastrointestinal symptoms and underwent EGD in the Department of Pediatrics, Juntendo University Hospital (January 2007-December 2018). Patients underwent serum IgG antibody tests, fecal antigen tests, or urea breath tests, and subsequently, culture tests by gastric mucosal biopsy during EGD. H. pylori positivity was defined as a positive result on both tests. Patients received triple therapy for 14 days using our regimen, and eradication was assessed at 2, 6, and 12 months after therapy. RESULTS: Forty-five patients were H. pylori-positive, and the overall clarithromycin (CAM) resistance rate was 71.1 % (32/45). The CAM resistance rate for the 2013-2018 period was significantly higher than the 2007-2012 period (52.6% vs. 84.6%, P < 0.05). According to the results of the antimicrobial susceptibility test, we prescribed effective antibiotics, and this resulted in a primary eradication rate of 97.7%. CONCLUSIONS: We suggest that antimicrobial susceptibility testing can significantly improve rates of primary eradication of H. pylori infection.

Nationwide survey of pediatric gastrointestinal endoscopy in Japan.

BACKGROUND AND AIM: The implementation rates of pediatric gastrointestinal endoscopy are increasing with advancements in the devices used and pediatricians' skills. As part of the Japan Pediatric Endoscopy Study Group, we aimed to investigate the rates of pediatric gastrointestinal endoscopy use and the associated adverse events through a nationwide survey. METHODS: A questionnaire was sent to 630 institutions in Japan. The numbers of pediatric gastrointestinal endoscopy cases and adverse events occurring during endoscopy, from April 2011 to March 2016, were investigated. RESULTS: Responses were obtained from 445 facilities. The total number of pediatric gastrointestinal endoscopies was 37 447 and that of endoscopic examinations was 32 219 (86.0%), with esophagogastroduodenoscopy accounting for 18 484 cases; ileal colonoscopy, 11 936; endoscopic retrograde cholangiopancreatography, 389; wireless capsule endoscopy, 897; and balloon-assisted enteroscopy, 513. The number of endoscopic treatments was 5228, followed by balloon dilatation (1703), foreign body removal (989), and polypectomy (822); 201 adverse events (0.54%) occurred, 79 of which presented during endoscopic examination (0.25%). Eight serious perforations were noted in 0.0054% and 0.025% of those undergoing esophagogastroduodenoscopy and colonoscopy, respectively. Overall, 122 adverse events (2.33%) occurred in association with endoscopic treatment. One case of cardiopulmonary arrest occurred because of accidental extubation. However, no deaths occurred. CONCLUSION: Endoscopic examinations had a slightly higher adverse event rate, because of an increase in endoscopic retrograde cholangiopancreatography and small intestine enteroscopy, than that reported in previous studies, but the adverse event rate of endoscopic treatment did not increase.

A novel mutation in the SLCO2A1 gene, encoding a prostaglandin transporter, induces chronic enteropathy.

Chronic enteropathy associated with SLCO2A1 gene (CEAS) is caused by loss-of-function mutations in SLCO2A1, which encodes a prostaglandin (PG) transporter. In this study, we report a sibling case of CEAS with a novel pathogenic variant of the SLCO2A1 gene. Compound heterozygous variants in SLCO2A1 were identified in an 8-year-old boy and 12-year-old girl, and multiple chronic nonspecific ulcers were observed in the patients using capsule endoscopy. The splice site mutation (c.940 + 1G>A) of the paternal allele was previously reported to be pathogenic, whereas the missense variant (c.1688T>C) of the maternal allele was novel and had not yet been reported. The affected residue (p.Leu563Pro) is located in the 11th transmembrane domain (helix 11) of SLCO2A1. Because SLCO2A1 mediates the uptake and clearance of PGs, the urinary PG metabolites were measured by liquid chromatography coupled to tandem mass spectrometry. The urinary tetranor-prostaglandin E metabolite levels in the patients were significantly higher than those in unaffected individuals. We established cell lines with doxycycline-inducible expression of wild type SLCO2A1 (WT-SLCO2A1) and the L563P mutant. Immunofluorescence staining showed that WT-SLCO2A1 and the L563P mutant were dominantly expressed on the plasma membranes of these cells. Cells expressing WT-SLCO2A1 exhibited time- and dose-dependent uptake of PGE2, while the mutant did not show any uptake activity. Residue L563 is very close to the putative substrate-binding site in SLCO2A1, R561 in helix 11. However, in a molecular model of SLCO2A1, the side chain of L563 projected outside of helix 11, indicating that L563 is likely not directly involved in substrate binding. Instead, the substitution of Pro may twist the helix and impair the transporter function. In summary, we identified a novel pathogenic variant of SLCO2A1 that caused loss-of-function and induced CEAS.

A novel segmental absence of intestinal musculature with small intestinal stenosis: a case report.

BACKGROUND: Segmental absence of intestinal musculature (SAIM) is a rare cause of intestinal obstruction and perforation due to partial or complete defects in the intestinal muscularis propria in neonates and is occasionally observed in adulthood. CASE PRESENTATION: The first case of small intestinal stenosis derived from SAIM, which was difficult to differentiate from Crohn's disease (CD), is reported. A 4-year-old girl presented with abdominal pain, anemia, and a positive fecal occult blood test. She was initially diagnosed with CD and started on treatment. Because her gastrointestinal symptoms persisted, her previous pediatricians tried to carry out capsule endoscopy, but it was not possible because the patency capsule was retained. Therefore, she was referred to our institute and re-evaluated. The patency capsule examination was repeated to re-evaluate small intestinal passage, but it stagnated again. Abdominal ultrasonography showed a poorly deformable intestinal tract that narrowed rapidly from the dilated segment and had a thin wall with an irregular laminar structure. In addition, unlike the typical ultrasonic CD findings, the power Doppler signal enhancement at the intestinal wall and "creeping fat sign" were not found. The patient was referred for laparoscopic observation to pediatric surgeons, who confirmed a prominently dilated intestinal tract 40 cm proximal to the ileocecal valve, which was resected. Histopathological findings showed longitudinal muscle hypoplasia of the resected, dilated intestinal tract and fat replacement of the muscle layer. At the stenosis site, the muscle layer was fibrotic and showed incomplete muscle arrangement. Because of these findings, she was diagnosed with SAIM. After the surgical treatment, no gastrointestinal symptoms relapsed, and the fecal occult blood test has remained negative for 2 years. Moreover, 8 months after surgery, double-balloon endoscopy showed no abnormalities, such as a longitudinal ulcer and cobblestone appearance. CONCLUSIONS: In the present case, SAIM involved not only intestinal ileus and perforation, but also small intestinal stenosis. Although no other reports have demonstrated the usefulness of abdominal ultrasonography for the diagnosis of SAIM, the present report suggests that ultrasonography may be useful for differentiating SAIM from CD by close observation of the area around the small intestinal stenosis.

Perforation in pediatric non-complicated appendicitis treated by antibiotics: the real incidence.

PURPOSE: The incidence of perforation during antibiotic therapy (AT) of children triaged as non-complicated acute appendicitis (NC-Ap) was investigated. METHODS: Abdominal ultrasonography (US) and/or computed tomography (CT) scans from cases of perforation identified at appendectomy for failed AT were reassessed blindly by a panel of board-certified specialists for any evidence of pre-AT morbidity suggestive of perforation. RESULTS: Of 521 cases triaged as NC-Ap, symptoms resolved with AT in 452 cases (86.8%). All 69/521 (13.2%) cases with persistent symptoms had urgent appendectomy, and 12/521 (2.3%) were found to have perforated. Blind reassessment of US and/or CT scans from these cases identified seven with evidence of perforation when they were triaged as NC-Ap. Thus, the actual incidence of perforation during AT for NC-Ap was actually 12-7 = 5/521 (0.95%). CONCLUSIONS: Perforation is generally believed to be a complication of AT, but inappropriate triaging of cases for AT can bias results by artificially inflating the number of perforations, in this study, by more than double. We are the first to assess the unbiased incidence of perforation during AT for NC-Ap, by reassessing pre-AT US and/or CT scans. The incidence of perforation during AT is actually negligible.