Jose Fernando Vera Chamorro

Dr. Jose Fernando Vera Chamorro


Research Focus & Metrics

Academic Career Length

30Years (1997-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 May 1997 in Journal of Pediatric Gastroenterology and Nutrition
Verified
Journal Article
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JCJose Fernando Vera Chamorro
Jose Fernando Vera Chamorro
MGMartin Gotteland
Martin Gotteland
ECEduardo Chavez
Eduardo Chavez
MVMaria T. Vial
Maria T. Vial
EKElena Kakarieka
Elena Kakarieka
OBOscar Brunser
Oscar Brunser

21 June 2019 in BMC Infectious Diseases
Verified
Journal Article
Open access
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BABetsy Verónica Arévalo
Betsy Verónica Arévalo
DRDiana F. Rojas-Rengifo
Diana F. Rojas-Rengifo
CJCarlos Alberto Jaramillo
Carlos Alberto Jaramillo
BMBelén Mendoza de Molano
Belén Mendoza de Molano
JCJose Fernando Vera Chamorro
Jose Fernando Vera Chamorro
MDMaria del Pilar Delgado
Maria del Pilar Delgado
The effectiveness of Helicobacter pylori first-line treatment has decreased drastically with the rise of strains resistant to clarithromycin. Therapy failure has also been described in patients with infections by strains with dissimilar antimicrobial susceptibilities. The present study aims to estimate the prevalence of resistance and heteroresistance to clarithromycin in H. pylori isolates from antrum and corpus of Colombian patients. The study material included 126 isolates from antrum and corpus biopsies from 63 symptomatic patients over 18 years old who had a gastric endoscopy performed on them between June 2014 to August 2016. PCR amplification and sequencing of the H. pylori 23S rDNA gene was performed to determine the presence of mutations associated with clarithromycin resistance. Random amplified polymorphic DNA analysis was implemented in cases of resistance and heteroresistance. The overall frequency of resistance to clarithromycin was 38.1% (24/63 patients), of which 19 patients had resistant isolates in both stomach segments (14 with A2143G mutation and 5 with A2142G mutation), and 5 patients had a heteroresistant status. The remaining 61.9% (39/63 patients) presented only susceptible isolates. DNA fingerprinting analysis showed different patterns in 4/22 paired isolates. The high prevalence of H. pylori clarithromycin-resistance obtained (> 15%) constitutes an alert for gastroenterologists and suggests the need for reconsideration of the current eradication regimen for H. pylori in the studied population. The data show that heteroresistance status is an additional factor to be considered in the assessment of resistance. In consequence, it is advisable to examine at least two biopsies from different gastric segments.

31 August 2019 in The Journal of Infection in Developing Countries
Verified
Journal Article
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DRDiana F Rojas-Rengifo
Diana F Rojas-Rengifo
BMBelen Mendoza
Belen Mendoza
CJCarlos Jaramillo
Carlos Jaramillo
PRPaula A Rodríguez-Urrego
Paula A Rodríguez-Urrego
JCJose Fernando Vera Chamorro
Jose Fernando Vera Chamorro
LSLuisa Fernanda Jiménez Soto
Luisa Fernanda Jiménez Soto
Introduction: The presence of H. pylori in the stomach is associated with gastric pathologies. However, its diagnosis through culture methods is challenging because of its complex nutritional requirements and microaerophilic conditions for optimal growth. The preferred method for rapid diagnosis of H. pylori is the Rapid Urease Test (RUT) from human biopsies, which relies on the high activity of the urease enzyme present in H. pylori. However, RUT cannot say much more information about H. pylori. This makes evident the need for bacterial culture to know essential information such as the strain type, the kind of infection present and the bacteria’s antibiotic susceptibility. Methodology: Gastric biopsies from 347 patients were used for H. pylori isolation. We correlated the culture results with the RUT and histological grading used at Hospital Universitario Fundación SantaFe de Bogotá (HU-FSFB), Colombia. The concordance between techniques was determined by the Cohen’s Kappa coefficient (K). The sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were also calculated. Results: The culture standardization was successful, and it could be applied for diagnosis in the clinical practice. H. pylori was positive by culture in 88 (26.34%) patients. The concordance of RUT and culture was strong (K= 0.805), and between histology and culture was moderate (K= 0.763) as well as for the gold standard defined and culture (K= 0.80). Conclusions: We present evidence that RUT and histological methods will be better interpreted for diagnosis of H. pylori if combined with bacterial isolation in cholesterol enriched culture.

1 November 2018 in Journal of Pediatric Gastroenterology and Nutrition
Verified
Journal Article
Closed access
YRYuliet L. Rosero
Yuliet L. Rosero
BABetsy Verónica Arévalo
Betsy Verónica Arévalo
MDMaría Pilar Delgado
María Pilar Delgado
JCJose Fernando Vera Chamorro
Jose Fernando Vera Chamorro
DGDaniella García
Daniella García
CJCarlos A. Jaramillo
Carlos A. Jaramillo

3 October 2018 in Revista de Gastroenterología de México
Verified
Journal Article
Open access
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RPR. Pierre
R. Pierre
MVM. Vieira
M. Vieira
RVR. Vázquez
R. Vázquez
INI. Ninomiya
I. Ninomiya
GMG. Messere
G. Messere
CMC. Morao
C. Morao
Introducción y objetivo La esofagitis eosinofílica es una enfermedad crónica, mediada inmunológicamente, descrita en series y publicaciones alrededor del mundo. En los últimos 20 años diversos estudios han intentado evaluar la incidencia y prevalencia de la enfermedad. El objetivo del presente trabajo es estimar la prevalencia de esofagitis eosinofílica en un grupo de niños atendidos en 36 centros de gastroenterología pediátrica de 10 países latinoamericanos. Materiales y métodos A través de un protocolo multicéntrico, observacional y transversal se estimó la prevalencia de período de esofagitis eosinofílica entre los niños atendidos en consulta externa y sometidos a endoscopia superior diagnóstica por cualquier motivo en 36 centros de 10 países latinoamericanos durante un período de 3 meses. Resultados: Entre abril y junio de 2016 108 casos de esofagitis eosinofílica fueron evaluados. Asimismo, un promedio de 29,253 consultas ambulatorias y 4,152 endoscopias superiores de carácter diagnóstico fueron realizadas en los 36 centros participantes. La tasa de prevalencia de esofagitis eosinofílica en la población estudiada (n = 29,253) fue de 3,69 casos × 1,000 (IC 95%: 3.04 a 4.44) y entre los niños sometidos a endoscopia superior de rutina (n = 4,152) fue de 26 x 1,000 (IC 95%: 22.6 a 29.4). Conclusión: La tasa general de prevalencia de período de esofagitis eosinofílica en un grupo de niños evaluados en 36 centros latinoamericanos de gastroenterología pediátrica resultó de 3,69 × 1,000, y entre aquellos sometidos a endoscopia fue de 26 × 1,000. La prevalencia mostró una importante variabilidad entre los países y centros participantes. Este es el primer estudio de prevalencia de esofagitis eosinofílica pediátrica en Latinoamérica. Introduction and objective Eosinophilic esophagitis is a chronic, immune-mediated disease described in case series and publications worldwide. Over the past twenty years, the authors of different studies have attempted to evaluate its incidence and prevalence. The objetive of the present study was to estimate the prevalence of eosinophilic esophagitis in a group of children seen at 36 pediatric gastroenterology centers in ten Latin American countries. Materials and methods A multicenter, observational, and cross-sectional study was conducted that estimated the period prevalence of eosinophilic esophagitis in children seen at outpatient consultation and that underwent diagnostic upper gastrointestinal endoscopy for any indication at 36 centers in 10 Latin American countries, within a 3-month time frame. Results: Between April and June 2016, 108 cases of eosinophilic esophagitis were evaluated. Likewise, an average of 29,253 outpatient consultations and 4,152 diagnostic upper gastrointestinal endoscopies were carried out at the 36 participating centers. The period prevalence of eosinophilic esophagitis in the population studied (n = 29,253) was 3.69 cases × 1,000 (95% CI: 3.04 to 4.44), and among the children that underwent routine upper gastrointestinal endoscopy (n = 4,152), it was 26 x 1,000 (95% CI: 22.6 to 29.4). Conclusions: The general period prevalence of eosinophilic esophagitis in a group of children evaluated at 36 Latin American pediatric gastroenterology centers was 3.69 × 1,000, and in the children that underwent endoscopy, it was 26 × 1,000. There was important prevalence variability between the participating countries and centers. The present analysis is the first study conducted on the prevalence of pediatric eosinophilic esophagitis in Latin America.

27 March 2020 in Revista Colombiana de Gastroenterología
Verified
Journal Article
Open access
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MBMaría Catalina Bagés
María Catalina Bagés
CMCarlos Fernando Chinchilla Mejía
Carlos Fernando Chinchilla Mejía
CPCatalina Ortíz Piedrahita
Catalina Ortíz Piedrahita
Clara Plata-GarciaClara Plata-Garcia
Clara Plata-Garcia
EMEnilda Martha Puello Mendoza
Enilda Martha Puello Mendoza
JCJose Fernando Vera Chamorro
Jose Fernando Vera Chamorro
Objetivo: generar recomendaciones sobre el diagnóstico y el tratamiento de la alergia a la proteína de la leche de vaca (APLV), que sirvan de referencia y consulta para los médicos pediatras y de cuidado primario. Materiales y métodos: el presente documento de posición de expertos fue desarrollado por un grupo de médicos, especialistas en diferentes áreas terapéuticas y con experiencia en APLV. Se definieron los temas más relevantes y se realizó una revisión de la literatura científica disponible, a fin de elaborar una propuesta de recomendaciones que fue discutida por los autores. Resultados: se elaboró un documento de posición que propone un enfoque práctico sobre la definición, el diagnóstico y el tratamiento de la APLV en el paciente pediátrico. Conclusiones: el diagnóstico temprano y el manejo adecuado de la APLV pueden contribuir a una disminución de la carga de esta enfermedad y sus complicaciones.