Genetic landscape of pediatric acute liver failure of indeterminate origin.

BACKGROUND AND AIMS: Pediatric acute liver failure (PALF) is a life-threatening condition. In Europe, the main causes are viral infections (12%-16%) and inherited metabolic diseases (14%-28%). Yet, in up to 50% of cases the underlying etiology remains elusive, challenging clinical management, including liver transplantation. We systematically studied indeterminate PALF cases referred for genetic evaluation by whole-exome sequencing (WES), and analyzed phenotypic and biochemical markers, and the diagnostic yield of WES in this condition. APPROACH AND RESULTS: With this international, multicenter observational study, patients (0-18 y) with indeterminate PALF were analyzed by WES. Data on the clinical and biochemical phenotype were retrieved and systematically analyzed. RESULTS: In total, 260 indeterminate PALF patients from 19 countries were recruited between 2011 and 2022, of whom 59 had recurrent PALF. WES established a genetic diagnosis in 37% of cases (97/260). Diagnostic yield was highest in children with PALF in the first year of life (41%), and in children with recurrent acute liver failure (64%). Thirty-six distinct disease genes were identified. Defects in NBAS (n=20), MPV17 (n=8), and DGUOK (n=7) were the most frequent findings. When categorizing, the most frequent were mitochondrial diseases (45%), disorders of vesicular trafficking (28%), and cytosolic aminoacyl-tRNA synthetase deficiencies (10%). One-third of patients had a fatal outcome. Fifty-six patients received liver transplantation. CONCLUSIONS: This study elucidates a large contribution of genetic causes in PALF of indeterminate origin with an increasing spectrum of disease entities. The high proportion of diagnosed cases and potential treatment implications argue for exome or in future rapid genome sequencing in PALF diagnostics.

Long-Term Outcomes of Patients With Progressive Familial Intrahepatic Cholestasis After Biliary Diversion.

OBJECTIVES: Progressive familial intrahepatic cholestasis is a heterogeneous group of genetic disorders characterized by disrupted bile homeostasis. Patients with this disease typically present with cholestasis and pruritus early in life and often progress to end-stage liver disease. The clinical symptoms that patients with progressive familial intrahepatic cholestasis encounter are usually refractory to medical treatment. Although the effects of biliary diversion surgery on native liver survival are not exactly known, this procedure may provide a positive impact on pruritus and laboratory parameters in these patients. MATERIALS AND METHODS: We retrospectively evaluated the clinical and laboratory characteristics of patients with progressive familial intrahepatic cholestasis who underwent partial external biliary diversion between 2002 and 2020 at our center. Diagnosis of progressive familial intrahepatic cholestasis was made by clinical, biochemical, and histopathological characteristics as well as genetic testing. RESULTS: Nine patients were included in the study. Five patients required liver transplant during follow-up, with 4 having liver transplant as a result of endstage liver disease (median interval of 5 years). In 1 patient, partial external biliary diversion was performed 1.5 years after liver transplant for severe diarrhea, metabolic acidosis, and hepatic steatosis. Four patients did not require liver transplant during follow-up (median follow-up time of 7.6 years). Pruritus responded well to partial external biliary diversion in all patients. Among laboratory values evaluated 6 months after biliary diversion, only albumin showed significant improvement. CONCLUSIONS: Partial external biliary diversion had favorable results on long-term follow-up. This procedure can provide the relief of pruritus and delay the requirement for liver transplant in patients with progressive familial intrahepatic cholestasis. In our view, partial external biliary diversion should be considered the first-line surgical management for patients with this disease.

Partial External Biliary Diversion for Severe Diarrhea After Liver Transplant in Patients with Progressive Familial Intrahepatic Cholestasis Type 1.

Progressive familial intrahepatic cholestasis is a heterogeneous group of autosomal recessive disorders, and liver transplant is the only curative treatment. A biliary diversion operation for disruption of enterohepatic circulation in patients with progressive familial intrahepatic cholestasis type 1 without cirrhosis is another option. We present a pediatric patient with progressive familial intrahepatic cholestasis type 1 who underwent liver transplant due to end-stage liver disease. After transplant, diarrhea and growth retardation complications resolved after partial external biliary diversion surgery.

Recommendations for Clinical Decision-making in Children with Type 1 Diabetes and Celiac Disease: Type 1 Diabetes and Celiac Disease Joint Working Group Report

It is well-known that in children with type 1 diabetes (T1D), the frequency of Celiac disease (CD) is increased due to mechanisms which are not fully elucidated but include autoimmune injury as well as shared genetic predisposition. Although histopathologic examination is the gold standard for diagnosis, avoiding unnecessary endoscopy is crucial. Therefore, for both clinicians and patients' families, the diagnosis of CD remains challenging. In light of this, a joint working group, the Type 1 Diabetes and Celiac Disease Joint Working Group, was convened, with the aim of reporting institutional data and reviewing current international guidelines, in order to provide a framework for clinicians. Several controversial issues were discussed: For CD screening in children with T1D, regardless of age, it is recommended to measure tissue transglutaminase-immunoglobulin A (tTG-IgA) and/or endomysial-IgA antibody due to their high sensitivity and specificity. However, the decision-making process based on tTG-IgA titer in children with T1D is still debated, since tTG-IgA titers may fluctuate in children with T1D. Moreover, seronegativity may occur spontaneously. The authors' own data showed that most of the cases who have biopsy-proven CD had tTG-IgA levels 7-10 times above the upper limit. The decision for endoscopy based solely on tTG-IgA levels should be avoided, except in cases where tTG-IgA levels are seven times and above the upper limit. A closer collaboration should be built between divisions of pediatric endocrinology and gastroenterology in terms of screening, diagnosis and follow-up of children with T1D and suspicious CD.

Familial Mediterranean Fever Mutation Analysis in Pediatric Patients With Inflammatory Bowel Disease: A Multicenter Study.

BACKGROUND: The aim of the study was to evaluate familial Mediterranean fever (FMF) mutation analysis in pediatric patients with inflammatory bowel disease (IBD). The relation between MEFV mutations and chronic inflammatory diseases has been reported previously. METHODS: Children with IBD (334 ulcerative colitis (UC), 224 Crohn's disease (CD), 39 indeterminate colitis (IC)) were tested for FMF mutations in this multicenter study. The distribution of mutations according to disease type, histopathological findings, and disease activity indexes was determined. RESULTS: A total of 597 children (mean age: 10.8 ± 4.6 years, M/F: 1.05) with IBD were included in the study. In this study, 41.9% of the patients had FMF mutations. E148Q was the most common mutation in UC and CD, and M694V in IC (30.5%, 34.5%, 47.1%, respectively). There was a significant difference in terms of endoscopic and histopathological findings according to mutation types (homozygous/ heterozygous) in patients with UC (P < .05). There was a statistically significant difference between colonoscopy findings in patients with or without mutations (P = .031, P = .045, respectively). The patients with UC who had mutations had lower Pediatric Ulcerative Colitis Activity Index (PUCAI) scores than the patients without mutations (P = .007). CONCLUSION: Although FMF mutations are unrelated to CD patients, but observed in UC patients with low PUCAI scores, it was established that mutations do not have a high impact on inflammatory response and clinical outcome of the disease.

Deep mining of oxysterols and cholestenoic acids in human plasma and cerebrospinal fluid: Quantification using isotope dilution mass spectrometry.

Both plasma and cerebrospinal fluid (CSF) are rich in cholesterol and its metabolites. Here we describe in detail a methodology for the identification and quantification of multiple sterols including oxysterols and sterol-acids found in these fluids. The method is translatable to any laboratory with access to liquid chromatography - tandem mass spectrometry. The method exploits isotope-dilution mass spectrometry for absolute quantification of target metabolites. The method is applicable for semi-quantification of other sterols for which isotope labelled surrogates are not available and approximate quantification of partially identified sterols. Values are reported for non-esterified sterols in the absence of saponification and total sterols following saponification. In this way absolute quantification data is reported for 17 sterols in the NIST SRM 1950 plasma along with semi-quantitative data for 8 additional sterols and approximate quantification for one further sterol. In a pooled (CSF) sample used for internal quality control, absolute quantification was performed on 10 sterols, semi-quantification on 9 sterols and approximate quantification on a further three partially identified sterols. The value of the method is illustrated by confirming the sterol phenotype of a patient suffering from ACOX2 deficiency, a rare disorder of bile acid biosynthesis, and in a plasma sample from a patient suffering from cerebrotendinous xanthomatosis, where cholesterol 27-hydroxylase is deficient.

New Findings of Immunodysregulation, Polyendocrinopathy, and Enteropathy X-linked Syndrome (IPEX); Granulomas in Lung and Duodenum.

Immune dysregulation, polyendocrinopathy and enteropathy, X-linked (IPEX) syndrome is a rare disorder caused by loss-of-function mutations in the gene forkhead box protein 3 (FOXP3). IPEX patients frequently show chronic diarrhea (enteropathy) associated with villous atrophies in the small intestine. Our case is different from this classical information in the literature, since he presented with neonatal onset inflammatory bowel disease within the first months of life accompanied by deep ulcers throughout colonic mucosa. Moreover, he developed chronic lung disease during follow-up and histopathological examinations showed granulomas in both gastrointestinal tract and lung parenchyma. Genetic analysis revealed the diagnosis of IPEX syndrome with a germline mutation in FOXP3. Thus, our study provides an unusual presentation of IPEX syndrome with colitis and granulomas presence in histopathological examinations.

Primary Eosinophilic Gastrointestinal Diseases Beyond Eosinophilic Esophagitis in Children.

OBJECTIVES: There are many unknowns about primary eosinophilic gastrointestinal disease (EGID) in childhood. The aim of this study is to provide data about the frequency, management, control level, and prognosis of well documented primary EGID in childhood. METHODS: This study was conducted in children who underwent endoscopy and/or colonoscopy at a single center over 10-year period up to August 2018. Primary EGID was diagnosed after exclusion of secondary EGID and classified as eosinophilic gastritis (EG), eosinophilic enteritis (EE), eosinophilic gastroenteritis (EGE: eosinophilic gastritis with eosinophilic enteritis) and eosinophilic colitis (EC) according to histopathological evaluation. The pathological number of eosinophil counts were accepted as >30 hpf for gastric mucosa in 5 hpf area, ≥20/hpf for duodenal, jejunal, and ileal mucosa, >50/hpf for right colonic mucosa, >35/hpf for transverse colonic mucosa, and >25/hpf for left colonic mucosa. Presenting symptoms, signs, management, follow-up, disease control level, and remission were analyzed. Remission is defined if the patient is controlled with all clinical, endoscopic/colonoscopic, and histopathologic parameters without any treatments or diet for at least a year. RESULTS: During the study period, 7457 biopsies were taken in 8262 endoscopy and/or colonoscopy procedures. Primary and secondary EGID frequencies were found 0.23% (n = 17 patients) and 0.1% (n =8 patients) per procedure with biopsy in children, respectively. Endoscopy/colonoscopy procedures were not able to performed in 9 patients because of short follow-up period (n = 6) or patients leaving follow-up (n = 3). Nine of the primary EGID patients had esophageal eosinophilia (EsE) at the time of diagnosis, 5 of them were previously managed as EoE. The median follow-up period of primary EGID patients excluding the ones without a control endoscopy/colonoscopy procedure was 3.35 years (min-max: 1.1-9.0 years). Proton pump inhibitors (PPI) were the most frequently used treatment alone or in combination with diet, systemic and/or topical corticosteroids. Disease control was evaluated in 8 of 17 patients and it was uncontrolled in 4, partially controlled in 1, and controlled in 3 patients. Remission was achieved in 2 patients. CONCLUSIONS: The frequency of primary EGID beyond eosinophilic esophagitis (EoE) in children is low. It may be difficult to achieve control in children with primary EGID in the long-term follow-up.

The evaluation of the use of 2D shear-wave ultrasound elastography in differentiation of clinically insignificant and significant liver fibrosis in pediatric age group.

OBJECTIVE: To determine the accuracy of 2D shear-wave elastography (2D-SWE) in pediatric age group patients in differentiating clinically insignificant and significant liver fibrosis using METAVIR fibrosis scoring system as the gold standard. INTRODUCTION: Liver biopsy has long been the gold standard in liver fibrosis diagnosis. However, due to probable complications and sampling variabilities, the need for more accurate and non-invasive techniques has increased. 2D-SWE is a non-invasive technique used in the evaluation of liver stiffness and utilized more and more in routine clinical practice with recent advances and researches. MATERIALS AND METHODS: In this retrospective single-center study, we included 46 pediatric age group patients who had a liver parenchymal biopsy and 2D-SWE evaluation regardless of etiology. For 2D-SWE, the LOGIQ E9 system (GE Medical Systems, Wisconsin, USA) and, for histopathological evaluation, METAVIR fibrosis scoring system were utilized. Patients were further subgrouped as clinically insignificant (METAVIR Score F0-1) and significant (METAVIR Score F2-4). The Kolmogorov-Smirnov and Mann-Whitney U tests were employed for statistical analysis. The diagnostic accuracy of 2D-SWE was assessed, and cutoff values were set by ROC curve analysis. RESULTS: kPa values were statistically different between clinically significant and insignificant fibrosis patient groups (p < 0.001). kPa value of 8.92 was designated as the best cutoff value according to the Youden Index. CONCLUSION: 2D-SWE is one of the non-invasive techniques in the evaluation of liver fibrosis. Our findings suggest that 2D-SWE accurately differentiate clinically insignificant and significant liver fibrosis.

Obstructive jaundice and severe pancreatitis due to the foramen of Winslow hernia with multiple anomalies.

Internal hernia through the foramen of Winslow is a very rare condition, especially in children. Here we report a 16-month-old girl who presented with obstructive jaundice and elevation of pancreatic enzymes and was ultimately diagnosed with internal hernia and malrotation by radiologic investigation and open approach surgery. To the best of our knowledge, obstructive jaundice with pancreatitis and other congenital abnormalities in children with the foramen of Winslow hernia have not been reported previously in the literature.

Defining clinical subgroups and genotype-phenotype correlations in NBAS-associated disease across 110 patients.

PURPOSE: Pathogenic variants in neuroblastoma-amplified sequence (NBAS) cause an autosomal recessive disorder with a wide range of symptoms affecting liver, skeletal system, and brain, among others. There is a continuously growing number of patients but a lack of systematic and quantitative analysis. METHODS: Individuals with biallelic variants in NBAS were recruited within an international, multicenter study, including novel and previously published patients. Clinical variables were analyzed with log-linear models and visualized by mosaic plots; facial profiles were investigated via DeepGestalt. The structure of the NBAS protein was predicted using computational methods. RESULTS: One hundred ten individuals from 97 families with biallelic pathogenic NBAS variants were identified, including 26 novel patients with 19 previously unreported variants, giving a total number of 86 variants. Protein modeling redefined the ß-propeller domain of NBAS. Based on the localization of missense variants and in-frame deletions, three clinical subgroups arise that differ significantly regarding main clinical features and are directly related to the affected region of the NBAS protein: ß-propeller (combined phenotype), Sec39 (infantile liver failure syndrome type 2/ILFS2), and C-terminal (short stature, optic atrophy, and Pelger-Huët anomaly/SOPH). CONCLUSION: We define clinical subgroups of NBAS-associated disease that can guide patient management and point to domain-specific functions of NBAS.

Portal Hypertensive Biliopathy as a Cause of Severe Cholestasis in Children With Congenital Hepatic Fibrosis.

Portal hypertensive biliopathy may occur in patients with noncirrhotic hepatic fibrosis. Portal hypertensive biliopathy treatment should be focused on management of portal hypertension and relief of biliary obstruction. In patients with noncirrhotic portal fibrosis and symptomatic portal hypertensive biliopathy, portal decompression surgery by proximal splenorenal shunt is one successful treatment option.

Predictable and Unusual Adverse Effects of Immunosuppression in Pediatric Liver Transplant Patients.

OBJECTIVES: Our aim was to determine potentially adverse effects of immunosuppressive protocols after liver transplantation in children. MATERIALS AND METHODS: The medical records of 60 children who underwent liver transplant retrospectively analyzed. Corticosteroid, tacrolimus, and mycophenolate mofetil were the primary immunosuppressive agents used in our center. RESULTS: The mean age of children was 6.1 years, ranging from 3 months to 17 years (34 boys, 26 girls). The most common indication for liver transplant was biliary atresia (26.7%). Thirty-nine patients (65%) received livers from living donors, and 21 patients (35%) received from livers from deceased donors. The main complications of immunosuppressive therapy were diarrhea associated with mycophenolate mofetil, hyperglycemia and hypertension associated with corticosteroid, and seizures and tremors associated with tacrolimus. Two patients developed post transplant lymphoproliferative disorder. The diagnosis was based on histologic findings of cervical lymphadenopathy and duodenal biopsy. One patient was diagnosed with acute lymphoblastic lymphoma. In addition to these predictable adverse effects, unusual adverse effects of immunosuppression were also observed. Hemolytic anemia (n = 3) (one was also diagnosed with Evans syndrome), eosinophilic gastroenteritis (n = 2), de novo food allergy (n = 2), posttransplant lymphoproliferative disorder (n = 2), Burkitt lymphoma (n = 1), and renal tubular acidosis (n = 1) were thought to be related to tacrolimus therapy. CONCLUSIONS: Adverse effects of immunosuppression represent a major cause of postoperative morbidity. The common effects of immunosuppression are recognized easily by clinicians. It should be kept in mind that unexpected symptoms and signs may be related to immunosuppression in pediatric liver transplant patients.

High incidence of co-existing factors significantly modifying the phenotype in patients with Fabry disease.

Fabry disease results from deficiency of the lysosomal enzyme alpha-galactosidase A. The families of 11 index cases were screened by enzyme and molecular assays. Further clinical and laboratory investigations were carried out in all cases. Including 33 new patients, a total of 28 females (Age 25,82 ±â€¯12,1 Range 8-46) and 16 males (Age 24,56 ±â€¯15,04 Range 2-48) were investigated. Ten different disease-causing variants were found two of them being novel. One patient had co-existing familial mediteranian fever, one had celiac disease and three had rheumatological disorders. Lipoprotein (a) levels were elevated in 17,6%, homocysteine in 22,2%, total and low density cholesterol in 12% and antithrombin 3 levels were elevated in 13,3%. One patient was found to be heterozygous for prothrombin p.G20210A disease-causing variant (5,8%) and two for factor V Leiden disease-causing variant (11,7%). Anticardiolipin IgM antibody was found to be positive in 11,7%. The patients with abnormal cranial imaging were also noticed to have additional risk factors for thrombosis. This study provides the largest data about Fabry patients from Turkey and implies that co-existing risk factors unrelated to Fabry Disease have significant association with the presence of clinical symptoms in females and might cause an early and severe clinical course in males.

The Frequency of Lysosomal Acid Lipase Deficiency in Children With Unexplained Liver Disease.

OBJECTIVES: Evidence suggests that lysosomal acid lipase deficiency (LAL-D) is often underdiagnosed because symptoms may be nonspecific. We aimed to investigate the prevalence of LAL-D in children with unexplained liver disease and to identify demographic and clinical features with a prospective, multicenter, cross-sectional study. METHODS: Patients (aged 3 months-18 years) who had unexplained transaminase elevation, unexplained hepatomegaly or hepatosplenomegaly, obesity-unrelated liver steatosis, biopsy-proven cryptogenic fibrosis and cirrhosis, or liver transplantation for cryptogenic cirrhosis were enrolled. A Web-based electronic data collection system was used. LAL activity (nmol/punch/h) was measured using the dried blood spot method and classified as LAL-D (<0.02), intermediate (0.02-0.37) or normal (> 0.37). A second dried blood spot sample was obtained from patients with intermediate LAL activity for confirmation of the result. RESULTS: A total of 810 children (median age 5.6 years) from 795 families were enrolled. The reasons for enrollment were unexplained transaminase elevation (62%), unexplained organomegaly (45%), obesity-unrelated liver steatosis (26%), cryptogenic fibrosis and cirrhosis (6%), and liver transplantation for cryptogenic cirrhosis (<1%). LAL activity was normal in 634 (78%) and intermediate in 174 (21%) patients. LAL-D was identified in 2 siblings aged 15 and 6 years born to unrelated parents. Dyslipidemia, liver steatosis, and mild increase in aminotransferases were common features in these patients. Moreover, the 15-year-old patient showed growth failure and microvesicular steatosis, portal inflammation, and bridging fibrosis in the liver biopsy. Based on 795 families, 2 siblings in the same family were identified as LAL-D cases, making the prevalence of LAL-D in this study population, 0.1% (0.125%-0.606%). In the repeated measurement (76/174), LAL activity remained at the intermediate level in 38 patients. CONCLUSIONS: Overall, the frequency of LAL-D patients in this study (0.1%) suggests that LAL-D seems to be rare even in the selected high-risk population.

Fibrinogen Gamma Chain Mutations Provoke Fibrinogen and Apolipoprotein B Plasma Deficiency and Liver Storage.

p.R375W (Fibrinogen Aguadilla) is one out of seven identified mutations (Brescia, Aguadilla, Angers, Al du Pont, Pisa, Beograd, and Ankara) causing hepatic storage of the mutant fibrinogen γ. The Aguadilla mutation has been reported in children from the Caribbean, Europe, Japan, Saudi Arabia, Turkey, and China. All reported children presented with a variable degree of histologically proven chronic liver disease and low plasma fibrinogen levels. In addition, one Japanese and one Turkish child had concomitant hypo-APOB-lipoproteinemia of unknown origin. We report here on an additional child from Turkey with hypofibrinogenemia due to the Aguadilla mutation, massive hepatic storage of the mutant protein, and severe hypo-APOB-lipoproteinemia. The liver biopsy of the patient was studied by light microscopy, electron microscopy (EM), and immunohistochemistry. The investigation included the DNA sequencing of the three fibrinogen and APOB-lipoprotein regulatory genes and the analysis of the encoded protein structures. Six additional Fibrinogen Storage Disease (FSD) patients with either the Aguadilla, Ankara, or Brescia mutations were investigated with the same methodology. A molecular analysis revealed the fibrinogen gamma p.R375W mutation (Aguadilla) but no changes in the APOB and MTTP genes. APOB and MTTP genes showed no abnormalities in the other study cases. Light microscopy and EM studies of liver tissue samples from the child led to the demonstration of the simultaneous accumulation of both fibrinogen and APOB in the same inclusions. Interestingly enough, APOB-containing lipid droplets were entrapped within the fibrinogen inclusions in the hepatocytic Endoplasmic Reticulum (ER). Similar histological, immunohistochemical, EM, and molecular genetics findings were found in the other six FSD cases associated with the Aguadilla, as well as with the Ankara and Brescia mutations. The simultaneous retention of fibrinogen and APOB-lipoproteins in FSD can be detected in routinely stained histological sections. The analysis of protein structures unraveled the pathomorphogenesis of this unexpected phenomenon. Fibrinogen gamma chain mutations provoke conformational changes in the region of the globular domain involved in the "end-to-end" interaction, thus impairing the D-dimer formation. Each monomeric fibrinogen gamma chain is left with an abnormal exposure of hydrophobic patches that become available for interactions with APOB and lipids, causing their intracellular retention and impairment of export as a secondary unavoidable phenomenon.

Avaliação de antígeno leucocitário humano classe I e II em pacientes pediátricos com gastrite e úlcera duodenal ativas e Helicobacter pylori positivo / Evaluation of human leukocyte antigen class i and ii antigens in helicobacter pylori-positive pediatric patients with active gastritis and duodenal ulcer

ABSTRACT BACKGROUND: As being the first bacteria determined to be carcinogenic, Helicobacter pylori (H. pylori) is a pathogen localized in the stomach in more than half of the world population. Some earlier studies have found a relation between tissue histocompatibility antigens and gastric cancers depending on the regions. OBJECTIVE: The present study aimed to determine the distribution of human leukocyte antigen (HLA) class I and class II antigens in H. pylori-positive pediatric patients with active gastritis and duodenal ulcer, excluding cancer cases, in our center. METHODS: The study included 40 patients diagnosed with H. pylori-positive active gastritis and duodenal ulcer and 100 controls consisting of healthy donor candidates. The HLA class I and class II antigens were studied in the isolated DNA samples using the polymerase chain reaction sequence-specific oligonucleotide probes. RESULTS: The frequency of HLA-B*51 antigen was significantly higher in the patient group than in the control group (40% vs 17%; P=0.003). There was no difference between the two groups in terms of the frequencies of HLA-A, HLA-C, HLA-DR, and HLA-DQ antigens. CONCLUSION: It was determined that HLA-B*51 plays a critical role in H. pylori infection.

RESUMO CONTEXTO: Determinada como sendo a primeira bactéria cancerígena, o Helicobacter pylori (H. pylori) é um patógeno localizado no estômago em mais da metade da população mundial. Alguns estudos anteriores têm encontrado uma relação entre câncer gástrico e antígenos de histocompatibilidade de tecido dependendo das regiões. OBJETIVO: O presente estudo teve como objetivo determinar a distribuição em nosso centro do antígeno leucocitário humano (HLA) de classe I e antígenos classe II em pacientes pediátricos H. pylori-positivos com gastrite e úlcera duodenal ativas, excluindo casos de câncer. MÉTODOS: O estudo incluiu 40 pacientes H. pylori-positivos diagnosticados com gastrite e úlcera duodenal ativas e 100 controles consistindo de candidatos doadores saudáveis. Foram estudadas nas amostras de DNA isoladas o antígeno leucocitário humano classe I e antígenos classe II, utilizando-se as cadeias de sequência específica de polimerase do oligonucleotideo. RESULTADOS: A frequência do antígeno HLA - B * 51 foi significativamente maior no grupo de pacientes do que no grupo controle (40% vs 17%; P=0,003). Não houve diferença entre os dois grupos em termos das frequências dos antígenos HLA-A, HLA-DR, HLA-DQ e HLA-C. CONCLUSÃO: Determinou-se que o HLA - B * 51 desempenha um papel crítico na infecção pelo H. pylori.

EVALUATION OF HUMAN LEUKOCYTE ANTIGEN CLASS I AND II ANTIGENS IN HELICOBACTER PYLORI-POSITIVE PEDIATRIC PATIENTS WITH ACTIVE GASTRITIS AND DUODENAL ULCER.

BACKGROUND: As being the first bacteria determined to be carcinogenic, Helicobacter pylori (H. pylori) is a pathogen localized in the stomach in more than half of the world population. Some earlier studies have found a relation between tissue histocompatibility antigens and gastric cancers depending on the regions. OBJECTIVE: The present study aimed to determine the distribution of human leukocyte antigen (HLA) class I and class II antigens in H. pylori-positive pediatric patients with active gastritis and duodenal ulcer, excluding cancer cases, in our center. METHODS: The study included 40 patients diagnosed with H. pylori-positive active gastritis and duodenal ulcer and 100 controls consisting of healthy donor candidates. The HLA class I and class II antigens were studied in the isolated DNA samples using the polymerase chain reaction sequence-specific oligonucleotide probes. RESULTS: The frequency of HLA-B*51 antigen was significantly higher in the patient group than in the control group (40% vs 17%; P=0.003). There was no difference between the two groups in terms of the frequencies of HLA-A, HLA-C, HLA-DR, and HLA-DQ antigens. CONCLUSION: It was determined that HLA-B*51 plays a critical role in H. pylori infection.

Multiple Presentations of LRBA Deficiency: a Single-Center Experience.

INTRODUCTION: LPS-responsive beige-like anchor protein (LRBA) deficiency is a primary immunodeficiency categorized as common variable immunodeficiency associated with autoimmune manifestations and inflammatory bowel diseases; however, the clinical spectrum has been extended. Here, we present our cohort of Turkish LRBA-deficient patients from a single center, demonstrating a diversity of clinical manifestations. METHOD: Seven affected individuals from five families were assessed retrospectively in this study. RESULTS: Of the seven patients with LRBA deficiency, four had homozygous, and two had compound heterozygous mutations. One patient remained disease free until the last follow-up (age 17 years). The most common clinical manifestations of the six symptomatic patients were organomegaly (6/6), autoimmunity (6/6), and chronic diarrhea (5/6). Recurrent infectious episodes were observed in three patients. None of the patients had hypogammaglobulinemia at presentation. B cell subpopulation analysis revealed low numbers of switched-memory B cell numbers in two of the four tested patients. During the disease course, three of the patients died, two of them underwent successful hematopoietic stem cell transplantation (HSCT) from matched sibling donors, and one is under abatacept therapy. CONCLUSION: LRBA defects should always be kept in mind as a differential diagnosis for patients with autoimmune disease affecting multiple organs, chronic diarrhea, and organomegalies. In our experience, early HSCT is a life-saving therapeutic strategy.

Differential diagnosis in ulcerative colitis in an adolescent: Chronic granulomatous disease needs extra attention.

Chronic granulomatous disease (CGD) is a primary immune deficiency that is commonly diagnosed under the age of 5 years (95%) and is rarely seen in adulthood. CGD may manifest as inflammatory bowel disease (IBD) in childhood. Without proper diagnosis, these patients may be monitored for years as IBD; some may even be regarded as steroid-resistant ulcerative colitis (UC) and end up having a colectomy. In this case report, we described a patient who had been followed-up for years as UC and subsequently underwent colectomy, but was finally diagnosed in adulthood as primary immune deficiency.