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Concordance of Helicobacter pylori Detection Methods in Symptomatic Children and Adolescents
(MDPI AG, 2025-03-04)
Camila Cabrera
;
Yanira Campusano
;
Joaquín Torres
;
Dinka Ivulic
;
Valeria Galvez
Background: Helicobacter pylori is the most prevalent chronic bacterial infection globally, acquired mostly during childhood. It is associated with chronic gastritis, peptic ulcer disease, and gastric cancer. Due to challenges in culturing H. pylori, diagnostic reference standards often rely on combining ≥2 non-culture, biopsy-based methods. Histology with Giemsa staining is widely used in clinical settings due to its low cost and reliable performance. Methods: This study evaluated the concordance between histology with Giemsa staining as the reference standard and other diagnostic methods, including the rapid urease test (RUT), ureA RT-PCR, 16S sequencing, and anti-H. pylori serum IgG. Positive percent of agreement (PPA), negative percent of agreement (NPA) and concordance kappa index were calculated. Results: A total of 120 patients (41 positive and 79 negative by Giemsa staining) were analyzed. Among the methods tested, RT-PCR for ureA showed the best performance (PPA = 94.7%, NPA = 98.6%, kappa = 0.939), while RUT underperformed compared with expectations (PPA = 65.9%, NPA = 97.5%, kappa = 0.681). Serology had the lowest performance (PPA = 53.7%, NPA = 96.1%, kappa = 0.548). Conclusions: The combination of histology with Giemsa staining and ureA RT-PCR achieved the highest detection rate and strongest agreement.</jats:p>
1
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Antimicrobial Resistance of <i>Helicobacter pylori</i> Isolated From Latin American Children and Adolescents (2008–2023): A Systematic Review
(2024)
Camila Cabrera
;
Joaquín Torres
;
Carolina A. Serrano
;
Paulina Gallardo
;
Vicente Orellana
<jats:title>ABSTRACT</jats:title><jats:sec><jats:title>Background</jats:title><jats:p>Latin America has a high prevalence of <jats:italic>Helicobacter pylori</jats:italic> in children that may lead to peptic ulcer disease and eventually gastric cancer in adulthood. Successful eradication is hindered by rising antimicrobial resistance. We summarize <jats:italic>H. pylori</jats:italic> resistance rates in Latin American children from 2008 to 2023.</jats:p></jats:sec><jats:sec><jats:title>Material and Methods</jats:title><jats:p>Systematic review following PRISMA guidelines and National Heart, Lung, and Blood Institute checklist to assess risk of bias (PROSPERO CRD42024517108) that included original cross‐sectional observational studies reporting resistance to commonly used antibiotics in Latin American children and adolescents. We searched in PubMed, LILACS, and SciELO databases.</jats:p></jats:sec><jats:sec><jats:title>Results</jats:title><jats:p>Of 51 studies, 45 were excluded. The quality of the six analyzed studies (297 <jats:italic>H. pylori</jats:italic>‐positive samples) was satisfactory. Phenotypic methods (<jats:italic>N</jats:italic> = 3) reported higher resistance rates than genotypic studies (<jats:italic>N</jats:italic> = 3). Clarithromycin resistance ranged from 8.0% to 26.7% (6 studies; 297 samples), metronidazole from 1.9% to 40.2% (4 studies; 211 samples), amoxicillin from 0% to 10.4% (3 studies; 158 samples), tetracycline resistance was not detected (3 studies; 158 samples), and levofloxacin resistance was 2.8% (1 study; 36 samples).</jats:p></jats:sec><jats:sec><jats:title>Conclusion</jats:title><jats:p>Scarce Latin American studies on <jats:italic>H. pylori</jats:italic> resistance, along with methodological heterogeneity, hinder conclusive findings. Clarithromycin and metronidazole (first‐line drugs) resistance is worrisome, likely impacting lower eradication rates. Urgent systematic surveillance or individual testing before treatment is necessary to enhance eradication.</jats:p></jats:sec>
Scopus© Citations 3 4
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Porcentaje de éxito de erradicación de Helicobacter pylori con tratamiento antibiótico empírico en pacientes pediátricos de un Hospital Terciario
(2023)
Sofía Darritchon Lama
;
Diego Díaz García
;
Marcela Toledo Cumplido
;
LUCERO ALVAREZ, YALDA CECILIA
<jats:p>La infección por Helicobacter pylori es una condición frecuente, que a largo plazo se asocia con desarrollo de enfermedad ulceropéptica y eventualmente cáncer gástrico, que se podrían prevenir con un tratamiento oportuno. Lo óptimo sería lograr un éxito de erradicación mayor al 90%, pero los tratamientos empíricos recomendados no logran esas tasas en condiciones reales.Objetivo: Determinar el porcentaje de éxito del tratamiento empírico de erradicación de primera línea contra H. pylori en pacientes pediátricos atendidos en un hospital terciario.Pacientes y Método: Estudio descriptivo retrospectivo en pacientes con infección por H. pylori detectado en biopsias gástricas y que hubieran recibido tratamiento antibiótico de primera línea durante el periodo 2017-2021. Se consideró erradicación exitosa el resultado negativo de test de antígeno en deposiciones o nuevas biopsias luego de ≥ 1 mes de finalizado el tratamiento.Resultados: Se identificaron 82 pacientes con infección por H. pylori, de los cuales 53 recibieron tratamiento de erradicación. De éstos, 26 (49%) fueron controlados con test de erradicación luego del tratamiento y en ellos el porcentaje de éxito fue de solo 38% (10/26).Conclusiones: La tasa de erradicación con los esquemas empíricos utilizados fue menor a la esperada, lo que evidencia el desafío de buscar estrategias más efectivas de tratamiento incluyendo el estudio de susceptibilidad a antimicrobianos. La adherencia de los pacientes al protocolo de seguimiento también fue baja, lo que deberá reforzarse en el futuro para poder realizar un manejo clínico más adecuado. </jats:p>
Scopus© Citations 4 2
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Adaptation to the reality of Latin America of the NASPGHAN/ESPGHAN 2016 Guidelines on the Diagnosis, Prevention and Treatment of Helicobacter pylori Infection in Pediatrics
(2020)
LUCERO ALVAREZ, YALDA CECILIA
21Scopus© Citations 9
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Helicobacter pylori outer membrane vesicles induce astrocyte reactivity through nuclear factor-κappa B activation and cause neuronal damage in vivo in a murine model
(2023)
Esteban Palacios
;
Lorena Lobos-González
;
Simón Guerrero
;
Marcelo J. Kogan
;
Baohai Shao
<jats:title>Abstract</jats:title><jats:sec> <jats:title>Background</jats:title> <jats:p><jats:italic>Helicobacter pylori (Hp)</jats:italic> infects the stomach of 50% of the world’s population. Importantly, chronic infection by this bacterium correlates with the appearance of several extra-gastric pathologies, including neurodegenerative diseases. In such conditions, brain astrocytes become reactive and neurotoxic. However, it is still unclear whether this highly prevalent bacterium or the nanosized outer membrane vesicles (OMVs) they produce, can reach the brain, thus affecting neurons/astrocytes. Here, we evaluated the effects of <jats:italic>Hp</jats:italic> OMVs on astrocytes and neurons in vivo and in vitro.</jats:p> </jats:sec><jats:sec> <jats:title>Methods</jats:title> <jats:p>Purified OMVs were characterized by mass spectrometry (MS/MS). Labeled OMVs were administered orally or injected into the mouse tail vein to study OMV-brain distribution. By immunofluorescence of tissue samples, we evaluated: GFAP (astrocytes), βIII tubulin (neurons), and urease (OMVs). The in vitro effect of OMVs in astrocytes was assessed by monitoring NF-κB activation, expression of reactivity markers, cytokines in astrocyte-conditioned medium (ACM), and neuronal cell viability.</jats:p> </jats:sec><jats:sec> <jats:title>Results</jats:title> <jats:p>Urease and GroEL were prominent proteins in OMVs. Urease (OMVs) was present in the mouse brain and its detection coincided with astrocyte reactivity and neuronal damage. In vitro, OMVs induced astrocyte reactivity by increasing the intermediate filament proteins GFAP and vimentin, the plasma membrane α<jats:sub>V</jats:sub>β<jats:sub>3</jats:sub> integrin, and the hemichannel connexin 43. OMVs also produced neurotoxic factors and promoted the release of IFNγ in a manner dependent on the activation of the transcription factor NF-κB. Surface antigens on reactive astrocytes, as well as secreted factors in response to OMVs, were shown to inhibit neurite outgrowth and damage neurons.</jats:p> </jats:sec><jats:sec> <jats:title>Conclusions</jats:title> <jats:p>OMVs administered orally or injected into the mouse bloodstream reach the brain, altering astrocyte function and promoting neuronal damage in vivo. The effects of OMVs on astrocytes were confirmed in vitro and shown to be NF-κB-dependent. These findings suggest that <jats:italic>Hp</jats:italic> could trigger systemic effects by releasing nanosized vesicles that cross epithelial barriers and access the CNS, thus altering brain cells.</jats:p> </jats:sec>
Scopus© Citations 36 2
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Helicobacter pylori, clinical, laboratory, and noninvasive biomarkers suggestive of gastric damage in healthy school-aged children: A case-control study
(2021)
Yalda Lucero
;
Anne J. Lagomarcino
;
Juan P. Torres
;
ROESSLER VERGARA, PATRICIA ANDREA
;
Nora Mamani
20 1Scopus© Citations 6
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Effect of
<i>Helicobacter pylori</i>
eradication therapy on clinical and laboratory biomarkers associated with gastric damage in healthy school‐aged children: A randomized non‐blinded trial
(2021)
LUCERO, YALDA
;
Anne J. Lagomarcino
;
Juan P. Torres
;
ROESSLER VERGARA, PATRICIA ANDREA
;
Nora Mamani
1 1Scopus© Citations 13
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Terapias cuádruples son superiores a terapia triple estándar en primera línea de erradicación de Helicobacter pylori en Chile
(2022)
Diego Reyes
;
Javier Ortiz
;
Eduardo Fuentes López
;
Sigall Budnik
;
Vicente Gándara
Scopus© Citations 9 11
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Valores de normalidad de eosinófilos en mucosa gástrica y duodenal de niños referidos a endoscopía digestiva alta
(2021)
Marlene Ortiz
;
Francisca Jaime
;
Loreto Ortiz
;
Ruby Carrasco
;
María José Orellana
<jats:p>Con el aumento de la incidencia de alergias alimentarias, la presencia de eosinófilos (Eos) en la mucosa gastrointestinal ha recibido mayor atención. Sin embargo, los valores de normalidad para el recuento de Eos en estómago y duodeno en pacientes pediátricos son aún limitados.Objetivo: Estimar valores de referencia de Eos en biopsias de estómago y duodeno de niños referidos a endoscopía digestiva alta (EDA).Pacientes y Método: Estudio transversal de biopsias de niños referidos a EDA. Se analizó el informe endoscópico, test de ureasa para presencia de H. pylori y evaluación histológica (nº células/campo de aumento mayor o CAM). Se describe la distribución de Eos como mediana y desviación estandar, así como también la distribución percentilar, dado que los recuentos no tuvieron distribución normal. Se realizó análisis estadístico con test χ2 , test de Wilcoxon, análisis de la varianza y curvas de regresión lineal según correspondiera.Resultados: De 170 pacientes derivados a EDA, 72 cumplían con criterios de “normalidad” (EDA normal en análisis macroscópico, test de ureasa negativo y biopsia normal). La mediana de edad fue 11 años (rango 4-16), 68% niñas. El recuento de Eos (promedio ± 1DE) en cuerpo gástrico (n = 27) fue 1,06 ± 1,79 Eos/CAM, en antro gástrico (n = 72) fue 1,13 ± 1,79 Eos/HPF, y en duodeno (n = 30) fue 10,44 ± 7,09 Eos/CAM. No se encontraron diferencias significativas por edad y sexo, así como tampoco según infección por H. pylori (p = 0,095).Conclusiones: Se propone como rango de referencia en niños un conteo en cuerpo gástrico de 0-3 Eos/CAM, en antro de 0-3 Eos/CAM y en duodeno de 3-17 Eos/CAM. Incluso en medios con alta prevalencia de infección por H. pylori, el recuento de Eos no parece ser un elemento distintivo, y éstos están presentes normalmente en la mucosa gastroduodenal.</jats:p>
1
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Corrigendum: Helicobacter pylori cagA+ Is Associated with Milder Duodenal Histological Changes in Chilean Celiac Patients
(2017)
YALDA CECILIA LUCERO ALVAREZ
;
Amaya Oyarzún
;
Miguel O'Ryan
;
Rodrigo Quera
;
Nelly Espinosa
9Scopus© Citations 1

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