Identification of Autoantigens in Pediatric Gastric Juices.

Purpose: This study aimed to investigate the presence of autoantigens in the gastric juices of children. Methods: Gastric juice and serum samples were obtained from 53 children <15 years of age who underwent gastric endoscopy. Among these, 8, 22, and 23 participants were in the age groups 0-5, 6-10, and 11-15 years, respectively. These samples were analyzed using two-dimensional electrophoresis (2-DE), immunoblot analysis, and matrix-assisted laser desorption ionization-time of-flight mass spectrometry. Furthermore, we reviewed the histopathological findings and urease test results and compared them with the results of 2-DE and immunoblot analysis. Results: There were no statistically significant differences in urease test positivity, grades of chronic gastritis, active gastritis, or Helicobacter pylori infiltration of the antrum and body among the three age groups. Three distinct patterns of gastric juice were observed on 2-DE. Pattern I was the most common, and pattern III was not observed below the age of 5 years. Histopathological findings were significantly different among active gastritis (p=0.037) and H. pylori infiltration (p=0.060) in the gastric body. The immunoblots showed large spots at an approximate pH of 3-4 and molecular weights of 31-45 kDa. These distinct, large positive spots were identified as gastric lipase and pepsin A and C. Conclusion: Three enzymes, which are normally secreted under acidic conditions were identified as autoantigens. Further investigation of the pathophysiology and function of autoantigens in the stomach is required.

Antigenic Determinant of Helicobacter pylori FlaA for Developing Serological Diagnostic Methods in Children.

The early diagnosis of Helicobacter pylori infection is important for gastric cancer prevention and treatment. Although endoscopic biopsy is widely used for H. pylori diagnosis, an accurate biopsy cannot be performed until a lesion becomes clear, especially in pediatric patients. Therefore, it is necessary to develop convenient and accurate methods for early diagnosis. FlaA, an essential factor for H. pylori survival, shows high antigenicity and can be used as a diagnostic marker. We attempted to identify effective antigens containing epitopes of high diagnostic value in FlaA. Full-sized FlaA was divided into several fragments and cloned, and its antigenicity was investigated using Western blotting. The FlaA fragment of 1345-1395 bp had strong immunogenicity. ELISA was performed with serum samples from children by using the 1345-1395 bp recombinant antigen fragment. IgG reactivity showed 90.0% sensitivity and 90.5% specificity, and IgM reactivity showed 100% sensitivity and specificity. The FlaA fragment of 1345-1395 bp discovered in the present study has antigenicity and is of high value as a candidate antigen for serological diagnosis. The FlaA 1345-1395 bp epitope can be used as a diagnostic marker for H. pylori infection, thereby controlling various gastric diseases such as gastric cancer and peptic ulcers caused by H. pylori.

Difference in macrophage migration inhibitory factor between preterm and term newborns and associating clinical factors: Preliminary study.

This study aimed to investigate the macrophage migration inhibitory factor (MIF) and associated clinical factors in neonates. Clinical information and blood samples were obtained from 77 neonates. Clinical details were reviewed from medical records, and MIF was measured by enzyme-linked immunosorbent assay using blood samples acquired within a week after birth. Statistical analyses were performed between plasma MIF concentration and clinical factors. Among the 77 newborn infants, 25 were born at <34 weeks of gestation (preterm), 25 at 34 to 37 weeks (late preterm), and 27 at term gestation. The mean MIF was 9849.5 ± 7187.8 pg/mL in preterm, 5718.7 ± 4596.4 in late preterm, and 5361.1 ± 3895.7 in term infants (P = .016). Among 25 preterm infants born at <34 weeks of gestation, MIF was significantly higher in infants with necrotizing enterocolitis (NEC, 19,478.6 ± 8162.4 pg/mL, n = 5) than that in infants without NEC (feeding intolerance 7173.7 ± 4203.0 pg/mL, n = 12 and others 7844.9 ± 5311.2 pg/mL, n = 8, P = .020). Elevated plasma MIF levels in the transitional period were significantly associated with preterm birth before 34 weeks of gestation and the development of NEC.

Increased Risk of Severe Gastric Symptoms by Virulence Factors vacAs1c, alpA, babA2, and hopZ in Helicobacter pylori Infection.

Two virulence factors of Helicobacter pylori, cagA and vacA, have been known to play a role in the development of severe gastric symptoms. However, they are not always associated with peptic ulcer or gastric cancer. To predict the disease outcome more accurately, it is necessary to understand the risk of severe symptoms linked to other virulence factors. Several other virulence factors of H. pylori have also been reported to be associated with disease outcomes, although there are many controversial descriptions. H. pylori isolates from Koreans may be useful in evaluating the relevance of other virulence factors to clinical symptoms of gastric diseases because the majority of Koreans are infected by toxigenic strains of H. pylori bearing cagA and vacA. In this study, a total of 116 H. pylori strains from Korean patients with chronic gastritis, peptic ulcers, and gastric cancers were genotyped. The presence of virulence factors vacAs1c, alpA, babA2, hopZ, and the extremely strong vacuolating toxin was found to contribute significantly to the development of severe gastric symptoms. The genotype combination vacAs1c/alpA/babA2 was the most predictable determinant for the development of severe symptoms, and the presence of babA2 was found to be the most critical factor. This study provides important information on the virulence factors that contribute to the development of severe gastric symptoms and will assist in predicting clinical disease outcomes due to H. pylori infection.

Changing prevalence of Helicobacter pylori infection in children and adolescents.

Helicobacter pylori infection has declined over recent decades. However, its prevalence remains high, and nearly 50% of the global population has been infected. In Korea, seroprevalence has steadily decreased in adults, but the status of H. pylori infection in children is unknown. The current status or trend of H. pylori infection in children is important because it can help estimate H. pylori-related diseases including gastric cancer in later life. In this review, the authors discuss the change in H. pylori infection rate among children and adolescents based on literature reviews and our research.

A Case of Congenital Common Bile Duct Web Treated with Balloon Dilation under Endoscopic Retrograde Cholangiopancreatography in a Young Child.

Web in common bile duct (CBD web) is very rare. It is usually asymptomatic and detected incidentally during surgery for other causes in adults. It can be congenital or acquired, however congenital CBD web is extremely rare. Currently, despite its invasiveness and complications, endoscopic retrograde cholangiopancreatography (ERCP) is considered as a useful diagnostic and therapeutic modality in children with hepatobiliary pancreatic diseases as in adults. Herein we report a case of congenital CBD web presenting with acute pancreatitis and choledocholithiasis in a 4-year-old girl which was diagnosed and treated using balloon dilation under ERCP. After balloon dilation of the web, a common pancreatobiliary channel was observed. To the best of our knowledge, a case of congenital CBD web with pancreatobiliary junctional abnormality treated using ERCP in a child has not been reported to date.

Risk Factors and Effects of Severe Late-Onset Hyponatremia on Long-Term Growth of Prematurely Born Infants.

PURPOSE: Sodium is an essential nutritional electrolyte that affects growth. A low serum sodium concentration in healthy premature infants beyond 2 weeks of life is called late-onset hyponatremia (LOH). Here, we investigated the association between LOH severity and growth outcomes in premature infants. METHODS: Medical records of premature infants born at ≤32 weeks of gestation were reviewed. LOH was defined as a serum sodium level <135 mEq/L regardless of sodium replacement after 14 days of life. Cases were divided into two groups, <130 mEq/L (severe) and ≥130 mEq/L (mild). Characteristics and growth parameters were compared between the two groups. RESULTS: A total of 102 premature infants with LOH were included. Gestational age ([GA] 27.7 vs. 29.5 weeks, p<0.001) and birth weight (1.04 vs. 1.34 kg, p<0.001) were significantly lower in the severe group. GA was a risk factor of severe LOH (odds ratio [OR], 1.328, p=0.022), and severe LOH affected the development of bronchopulmonary dysplasia (OR, 2.950, p=0.039) and led to a poor developmental outcome (OR, 9.339, p=0.049). Growth parameters at birth were lower in the severe group, and a lower GA and sepsis negatively affected changes in growth for 3 years after adjustment for time. However, severe LOH was not related to growth changes in premature infants. CONCLUSION: Severe LOH influenced the development of bronchopulmonary dysplasia and developmental outcomes. However, LOH severity did not affect the growth of premature infants beyond the neonatal period.

Dynamic Changes of Fecal Calprotectin and Related Clinical Factors in Neonates.

Objective: Fecal calprotectin (FC) has been widely used for a clinical marker of intestinal inflammation in children and adults. However, the clinical usefulness has not been determined in neonates. The purpose of this study was to investigate the change of FC and associated clinical factors in neonates. Methods and Materials: In total, 146 neonates among 472 admissions to our NICU between 2018 and 2019 were included, and 242 stool samples were collected. FC was measured in the first, second, and third-fourth week after birth, respectively, using commercial ELISA. The clinical characteristics were reviewed from medical records. Statistical analyses were performed to analyze associated factors regarding on changes of fecal calprotectin. Results: A wide range from 5.5 to 6,000 mg/kg of FC was observed in neonates. FCs during neonatal period were not correlated with the gestational age at birth or birth weight. The meconial calprotectin was higher than FCs after 2 weeks of age (n = 134, 418.06 vs. 243.12 in the second week and 259.58 in the third week after birth). Meconial calprotectin was associated with birth weight and meconium stained amniotic fluid. FC during the neonatal period decreased with postnatal week (-464.93 ± 158.02 at third-fourth week after birth compared with the 1st week, P = 0.004) and breast milk (-337.27 ± 150.51 compared with formula milk, P = 0.026). Conclusion: Fecal calprotectin tended to decrease with postnatal week during the neonatal period, and breast milk could affect more decrease of FC.

Changes in Seroprevalence of Helicobacter pylori Infection over 20 Years in Jinju, Korea, from Newborns to the Elderly.

BACKGROUND: The objective of this study was to examine changes in the prevalence of cytotoxic-associated gene A (CagA) positive Helicobacter pylori infection in Jinju, Korea, over the last 20 years. METHODS: Three cross-sectional analyses were conducted concurrently. A total of 1,305 serum samples were collected from 1994-1995, 2004-2005, and 2014-2015, respectively. The presence of immunoglobulin (Ig) G, IgA, and IgM antibodies against H. pylori CagA protein was examined by western blotting. RESULTS: Overall, seropositivity for anti-CagA IgG antibody was significantly decreased from 63.2% to 42.5% over the last 20 years (P < 0.001). Anti-CagA IgG seropositivities in children and young adults aged 10-29 years decreased from 1994 (60.0%-85.0%) to 2015 (12.5%-28.9%). The age when plateau of increasing IgG seropositivity was reached in each study period shifted from the 15-19 year-old group in 1994-1995 (85.0%) to the 40-49 year-old group in 2014-2015 (82.5%). Overall seropositive rates of anti-CagA IgA and IgM antibodies did not change significantly either over the last 20 years. CONCLUSION: H. pylori infection rate in children and young adults declined over 20 years in Jinju, probably due to improved sanitation, housing, or economy.

Severe Gastrointestinal Hemorrhage in a Child after Taking an Improper Oral Rehydration Solution.

Oral rehydration solution (ORS) is safe and effective for the prevention and treatment of dehydration in children. It has been commercially available as a small packaging unit that needs to be taken with a specified amount of water. Intake of incorrectly formulated ORS results in side effects, such as electrolyte imbalance and upper gastrointestinal (GI) disturbance. We experienced a case of severe GI hemorrhage from gastric and duodenal ulcers in a previously healthy child following intake of incorrectly formulated ORS. GI hemorrhage in children is often life threatening and reaching a diagnosis may be challenging. Commercially manufactured packets of powdered oral rehydration salts have been widely used and GI hemorrhage associated with an improperly diluted ORS has been rarely reported. Caution and education for proper preparation of ORS are imperative.

Report: central diabetes insipidus and schwannoma in a male with X-linked congenital adrenal hypoplasia.

BACKGROUND: DAX1 mutations are related to the X-linked form of adrenal hypoplasia congenita (AHC) in infancy and to hypogonadotropic hypogonadism (HH) in puberty. We report a male patient affected by X-linked AHC who presented with central diabetes insipidus and schwannoma in adulthood, which has not been described in association with AHC. CASE PRESENTATION: A 36-day-old male infant who presented with severe dehydration was admitted to the intensive care unit. His laboratory findings showed hyponatremia, hyperkalemia, hypoglycemia, and metabolic acidosis. After hormonal evaluation, he was diagnosed with adrenal insufficiency, and he recovered after treatment with hydrocortisone and a mineralocorticoid. He continued to take hydrocortisone and the mineralocorticoid after discharge. At the age of 17, he did not show any signs of puberty. On the basis of a GnRH test, a diagnosis of HH was made. At the age of 24, he was hospitalized with thirst, polydipsia and polyuria. He underwent a water deprivation test for polydipsia and was diagnosed with central diabetes insipidus. By quantitative polymerase chain reaction analysis, we identified a hemizygous frameshift mutation in DAX1 (c.543delA). CONCLUSIONS: We suggest that DAX1 mutations affect a wider variety of endocrine organs than previously known, including the posterior pituitary gland.

Changes in the Treatment Strategies for Helicobacter pylori Infection in Children and Adolescents in Korea.

The policies developed for the treatment of Helicobacter pylori infection in adults may not be the most suitable ones to treat children and adolescents. Methods used to treat children and adolescents in Europe and North America may not be appropriate for treating children and adolescents in Korea due to differences in epidemiological characteristics of H. pylori between regions. Moreover, the agreed standard guidelines for the treatment of H. pylori infection in children and adolescents in Korea have not been established yet. In this study, the optimal treatment strategy for H. pylori infection control in children and adolescents in Korea is discussed based on these guidelines, and recent progress on the use and misuse of antimicrobial agents is elaborated. Non-invasive as well as invasive diagnostic test and treatment strategy for H. pylori infection are not recommendable in children aged less than ten years or children with body weight under 35 kg, except in cases of clinically suspected or endoscopically identified peptic ulcers. The uncertainty, whether enough antimicrobial concentrations to eradicate H. pylori can be maintained when administered according to body weight-based dosing, and the costs and adverse effects outweighing the anticipated benefits of treatment make it difficult to decide to eradicate H. pylori in a positive non-invasive diagnostic test in this age group. However, adolescents over ten years of age or with a bodyweight of more than 35 kg can be managed aggressively as adults, because they can tolerate the adult doses of anti-H. pylori therapy. In adolescents, the prevention of future peptic ulcers and gastric cancers is expected after the eradication of H. pylori. Bismuth-based quadruple therapy (bismuth-proton pump inhibitor-amoxicillin/tetracycline-metronidazole) with maximal tolerable doses and optimal dose intervals of 14 days is recommended, because in Korea, the antibiotic susceptibility test for H. pylori is not performed at the initial diagnostic evaluation. If the first-line treatment fails, concomitant therapy plus bismuth can be attempted for 14 days as an empirical rescue therapy. Finally, the salvage therapy, if needed, must be administered after the H. pylori antibiotic susceptibility test.

Monocyte Chemoattractant Protein (MCP)-1 in Rotavirus-Associated White Matter Injury in Newborns.

Recent reports have suggested an association between rotavirus infection and a distinctive pattern of white matter injury (WMI) in neonates with seizures; however, the connection between the two is not fully understood. To evaluate the underlying mechanism, we profiled and compared eight cytokines (IL [interleukin]-1ß, IL-6, IL-8, IL-10, IFN-γ [interferon-γ ], MCP-1 [monocyte chemoattractant protein-1], MIP-1ß [macrophage inflammatory protein-1ß], and TNF-α [tumor necrosis factor-α]) in the cerebrospinal fluid (CSF) of 33 neonates with seizures who had no other well-known causes of seizures and 13 control patients (rotavirus-induced gastroenteritis but without seizures). Among the 33 neonates with seizures, 9 showed WMI and all were infected with rotavirus (R + W + ). Among the 24 patients without WMI, 11 were infected with rotavirus (R + W - ) and 13 were not (R - W - ).Only MCP-1 and MIP-1ß were different between the groups. MCP-1 was increased in R+ W+ compared with R + W- (p < 0.01), R - W- (p < 0.01), and control (p = 0.03) patients. MIP-1ß was decreased in R + W+ compared with R - W- (p < 0.01) and control (p < 0.01), but not R + W- (p = 0.23) patients. MCP-1 and MIP-1ß are C-C chemokines that recruit immune cells to the site of inflammation. Our pilot study suggests MCP-1-mediated monocyte recruitment may be linked with this complication caused by rotavirus.

Neonatal seizures and white matter injury: Role of rotavirus infection and probiotics.

BACKGROUND: Recent reports associate rotavirus infection with neonatal seizures of distinctive white matter injury (WMI) pattern, but evidence is lacking. We examined this association prospectively and analyzed factors related to occurrence of seizures and WMI pattern in neonates with rotavirus infection. METHODS: We prospectively included 228 neonates (≥34 gestational weeks) who were admitted to a regional neonatal intensive care unit between February 2015 and April 2016 and underwent rotavirus antigen testing using stool samples. Patients with neonatal seizures of other etiologies were excluded. RESULTS: Seventy-eight (34.2%) neonates were rotavirus-positive. Otherwise-unexplained seizures were more frequently observed among rotavirus-positive than among rotavirus-negative neonates (20.5% vs. 4.0%, p < 0.001). Rotavirus infection increased the risk of seizures (odds ratio [OR], 6.19; p < 0.001), even after adjustment for confounders (OR, 4.46; p = 0.007). After stratification according to probiotic administration immediately after birth, rotavirus infection remained a significant risk factor only in patients without probiotic medication (OR, 4.83; p = 0.01 vs. OR, 2.44; p = 0.49). The WMI pattern was observed in 9 of 22 neonates with seizures, and this subgroup was characterized by rotavirus infection (100% vs. 53.8%, p = 0.004) and seizure onset on days 4-6 of life (66.7% vs. 15.0%; p = 0.02). G9P[8] was the most common genotype in this subgroup but was also commonly detected in neonates without seizures. CONCLUSION: Rotavirus infection is an independent risk factor for neonatal seizures, and associated with the WMI. Immediate administration of probiotics after birth may reduce rotavirus-associated neonatal seizures.

Diagnosis of Helicobacter pylori Infection in Children and Adolescents in Korea.

Helicobacter pylori plays an important role in the pathogenesis of chronic gastritis, peptic ulcer disease, gastric cancer, and gastric mucosa-associated lymphoid tissue lymphoma. In Korea, the guidelines for the diagnosis and treatment of H. pylori infection in adults were revised in 2013. The European Helicobacter and Microbiota Study Group and Consensus panel released the fifth edition of the Maastricht Consensus Report for the management of H. pylori infection in 2015, and the European Society of Paediatric Gastroenterology, Hepatology and Nutrition and the North American Society of Paediatric Gastroenterology, Hepatology and Nutrition released the updated joint guidelines for children and adolescents in 2016. Considering these recommendations and recent progress in our research and that of other research teams, this study aimed to discuss the diagnostic strategies for H. pylori infection in children and adolescents.

A Pilot Study Evaluating Cerebral Vasculitis in Kawasaki's Disease.

Cerebral vasculitis is thought to be a possible underlying mechanism of severe neurological complications of Kawasaki's disease (KD), such as cerebral infarct or aneurysm rupture. To evaluate the intracranial inflammatory response in patients with acute-stage KD, we measured the levels of cytokines (interleukin [IL]-6 and tumor necrosis factor [TNF]-α) and pentraxin-3 (PTX3) in the cerebrospinal fluid of patients with KD (n = 7) and compared the levels to those of the age- and sex-matched febrile control patients (bacterial meningitis [n = 5], enteroviral meningitis [n = 10], nonspecific viral illness without central nervous system involvement [n = 10]). PTX3 and TNF-α were rarely detected and only in trace concentration in KD, and the levels of IL-6 were not different from those of nonspecific viral illnesses. These mediators are not established biomarkers for cerebral vasculitis but might reflect vascular inflammation in various diseases including KD. Therefore, intracranial inflammation including vasculitis seems to be insignificant in our patients with KD. However, our results might be attributed to the fact that these patients lacked any clinical signs of cerebral or coronary vessel involvement. None of them underwent brain imaging. To clarify this issue, further studies involving patients with neurologic symptoms and proven involvement of cerebral vessels are needed.

Mild encephalopathy with a reversible splenial lesion in a girl with acute pyelonephritis.

We report the case of a 12-year-old girl who had mild encephalopathy with a reversible splenial lesion (MERS) associated with acutepyelonephritis caused by Escherichia coli. The patient was admitted with a high fever, and she was diagnosed with acute pyelonephritis based on pyuria and the results of urine culture, which detected cefotaxime-sensitive E. coli. Although intravenous cefotaxime and tobramycin were administered, her fever persisted and her C-reactive protein level increased to 307 mg/L. On day 3 of admission, she demonstrated abnormal neuropsychiatric symptoms, such as delirium, ataxia, and word salad. Magnetic resonance imaging (MRI) of the brain performed on day 4 showed marked hyperintensities in the bilateral corpus callosum and deep white matter on diffusion-weighted images, with corresponding diffusion restriction on apparent diffusion coefficient mapping. No abnormalities or pathogens were detected in the cerebrospinal fluid; however, lipopolysaccharides (LPS, endotoxin) were detected in plasma (41.6 pg/mL), associated with acute neurological deterioration. Her clinical condition gradually improved, and no neurological abnormalities were observed on day 6. Follow-up brain MRI performed 2 weeks later showed near-disappearance of the previously noted hyperintense lesions. In this patient, we first proved endotoxemia in a setting of MERS. The release of LPS following antibiotic administration might be related to the development of MERS in this patient. The possibility of MERS should be considered in patients who present with acute pyelonephritis and demonstrate delirious behavior.

Characterizing antigenic determinants in Helicobacter pylori CagA capable of detecting serum antibodies in children.

Helicobacter pylori can persistently colonize the mucosa of the human stomach, resulting in gastric disorders. Endoscopic biopsy for rapid urease test and histopathologic examination are considered as the most accurate diagnostic methods for H. pylori infection. Serological methods are recommended for children because of invasiveness of the diagnosis mentioned above. Here, the cytotoxin-associated gene A protein (Cag A), as an immunodominant antigen, was subdivided to determine which regions harbor antigenicity for humans. CagA was divided into 17 overlapping fragments of ∼400 bp, which were used for the analysis of antigenic determinants. The partial proteins were subjected to immunoblot analysis using pooled serum samples from children with gastric symptoms. A partial recombinant CagA protein containing epitope regions (683-749 amino acids), which were identified in this study, was produced and used for the detection of anti-CagA antibodies and further investigated its serodiagnostic value for determination of H. pylori infection in children. The serum IgG reactivities from children with gastric symptoms were significantly three times more than that of serum samples from children with non-gastric symptoms (P < 0.005). Moreover, the serum IgG reactivities from children showing strong urease activity of gastric biopsies were significantly higher than those with moderate and weak urease activities (P < 0.05). Hence, the partial CagA is a candidate antigen for diagnosis of H. pylori infection.

Helicobacter pylori Antigens Inducing Early Immune Response in Infants.

To identify the Helicobacter pylori antigens operating during early infection in sera from infected infants using proteomics and immunoblot analysis. Two-dimensional (2D) large and small gel electrophoresis was performed using H. pylori strain 51. We performed 2D immunoglobulin G (IgG), immunoglobulin A (IgA), and immunoglobulin M (IgM) antibody immunoblotting using small gels on sera collected at the Gyeongsang National University Hospital from 4-11-month-old infants confirmed with H. pylori infection by pre-embedding immunoelectron microscopy. Immunoblot spots appearing to represent early infection markers in infant sera were compared to those of the large 2D gel for H. pylori strain 51. Corresponding spots were analyzed by matrix-assisted laser desorption/ionization time of flight-mass spectrometry (MALDI-TOF-MS). The peptide fingerprints obtained were searched in the National Center for Biotechnology Information (NCBI) database. Eight infant patients were confirmed with H. pylori infection based on urease tests, histopathologic examinations, and pre-embedding immunoelectron microscopy. One infant showed a 2D IgM immunoblot pattern that seemed to represent early infection. Immunoblot spots were compared with those from whole-cell extracts of H. pylori strain 51 and 18 spots were excised, digested in gel, and analyzed by MALDI-TOF-MS. Of the 10 peptide fingerprints obtained, the H. pylori proteins flagellin A (FlaA), urease ß subunit (UreB), pyruvate ferredoxin oxidoreductase (POR), and translation elongation factor Ts (EF-Ts) were identified and appeared to be active during the early infection periods. These results might aid identification of serological markers for the serodiagnosis of early H. pylori infection in infants.