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Dive into the research topics where Antonio Rollán is active.

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Featured researches published by Antonio Rollán.


Journal of Clinical Gastroenterology | 1995

Endoscopic intrasphincteric injection of botulinum toxin for the treatment of achalasia.

Antonio Rollán; Robinson Gonzalez; Sergio Carvajal; Jose Chianale

Three patients with achalasia were treated with endoscopic injection of botulinum toxin (BoTx). BoTx (80 U) was injected via a sclerotherapy needle into the lower esophageal sphincter (LES). One patient complained of transient heartburn that resolved after omeprazole treatment. Two patients reported sustained symptomatic improvement. They were able to eat normally 48 h after treatment and have remained symptom free for 5 and 6.5 months, respectively. In these patients, esophageal manometry 4 months after treatment showed a marked reduction of resting LES pressure and the appearance of a previously absent LES relaxation after swallowing. The third patient had only a transient clinical improvement, with occasional dysphagia beginning 3 months after treatment. All patients showed unchanged aperistalsis of the esophageal body. Its less invasive nature compared with other therapeutic alternatives may give BoTX injection a role in the treatment of some patients with achalasia.


Revista Medica De Chile | 2010

[Helicobacter pylori infection in symptomatic patients with benign gastroduodenal diseases: analysis of 5.664 cases].

Juan Pablo Ortega; Alberto Espino; Alfonso Calvo B; Patricia Verdugo; Martha Pruyas; Eva Nilsen V; Luis Villarroel; Oslando Padilla; Arnoldo Riquelme; Antonio Rollán

UNLABELLEDnInfection with Helicobacter pylori (H. pylori) is highly prevalent in Chile, but there are no systematic studies in patients with upper gastrointestinal symptoms.nnnAIMnTo determine the prevalence of H. pylori infection, according to age, gender and endoscopic pathology in a large sample of patients.nnnMETHODSnWe studied 7,893 symptomatic patients submitted to upper gastrointestinal endoscopy between July 1996 and December 2003 in the context of a screening program of gastric cancer in a high risk population. H. pylori infection was determined by rapid urease test (RUT) in antral mucosa. We excluded 158 patients with gastric cancer (2%) and 2,071 patients without RUT.nnnRESULTSnWe included 5,664 patients, mean age 50.7 +/- 13.9 years, women 72.1%. Endoscopic diagnoses were normal in 59.3%, erosive esophagitis in 20%, gastric ulcer (GU) in 8.1%, duodenal ulcer (DU) in 6.4%, and erosive gastropathy in 6.2%. RUT was positive in 78% of patients. After adjusting for age and sex and with respect to patients with normal endoscopy, frequency of H. pylori infection was 86.6% in DU (OR 2.1, 95% CI 1.5-2.8, p < 0.001); 81.4% in GU (OR 1.8, 95% CI 1.4-2.4; p < 0.001 ); 79.9% in erosive gastropathy (OR 1.4, 95% CI 1.03-1.8; p = 0.03) and 77.4% in erosive esophagitis (OR 1.1, 95% CI: 0.9-1.3; p = NS). The probability of H. pylori infection decreased significantly with age, more markedly in men with normal endoscopy.nnnCONCLUSIONSnPrevalence of H. pylori infection is very high in symptomatic Chilean patients and even higher in those with gastroduodenal ulcer or erosions, while in patients with erosive esophagitis is similar to those with normal endoscopy. The frequency of infection decreases with age, probably as a consequence of rising frequency of gastric mucosal atrophy.


Gastrointestinal Endoscopy | 1998

Intestinal ischemia complicating paroxysmal nocturnal hemoglobinuria.

Rodrigo Zapata; Juan G. Mella; Antonio Rollán

Paroxysmal nocturnal hemoglobinuria (PNH) is a rare acquired disorder of hematopoiesis characterized by pancytopenia, intravascular hemolysis, and bone marrow aplasia. It is manifested by repeated episodes of hemoglobinuria and a tendency for the development of widespread venous thrombosis, which may affect unusual sites, such as hepatic and mesenteric veins.1 Many patients suffer from recurrent attacks of abdominal pain that are assumed to be secondary to intestinal venous thrombosis. However, there is little direct evidence to support this hypothesis. We describe here a rare case of PNH: a patient who developed abdominal pain with clinical, endoscopic, and histologic findings suggestive of ischemic small bowel disease and who survived this severe complication. To our knowledge, this is the first report showing serial endoscopic images of this complication in a PNH patient.


Revista Medica De Chile | 2014

Diagnóstico precoz de cáncer gástrico: Propuesta de detección y seguimiento de lesiones premalignas gástricas: protocolo ACHED

Antonio Rollán; Pablo Cortés; Calvo A; Raúl Araya; María E. Bufadel; Robinson G. Gonzalez; Carolina Heredia; Pablo Muñoz; Freddy Squella; Roberto Nazal; María de los Ángeles Gatica; Jaquelina Gobelet; René Estay; Raúl Pisano V; Luis Contreras; Ingrid Osorio; Ricardo Estela; Fernando Fluxá; Adolfo Parra-Blanco

An expert panel analyzed the available evidence and reached a consensus to release 24 recommendations for primary and secondary prevention of gastric cancer (CG) in symptomatic patients, with indication for upper GI endoscopy. The main recommendations include (1) Search for and eradicate H. pylori infection in all cases. (2) Systematic gastric biopsies (Sydney protocol) in all patients over 40 years of age or first grade relatives of patient with CG, to detect gastric atrophy, intestinal metaplasia or dysplasia. (3) Incorporate the OLGA system (Operative Link on Gastritis Assessment) to the pathological report, to categorize the individual risk of CG. (4) Schedule endoscopic follow-up according to the estimated risk of CG, namely annual for OLGA III- IV, every 3 years for OLGA I- II or persistent H. pylori infection, every 5 years for CG relatives without other risk factors and no follow-up for OLGA 0, H. pylori (-). (4) Establish basic human and material resources for endoscopic follow-up programs, including some essential administrative processes, and (5) Suggest the early CG/total CG diagnosis ratio of each institution and the proportion of systematic recording of endoscopic images, as quality indicators. These measures are applicable using currently available resources, they can complement any future screening programs for asymptomatic population and may contribute to improve the prognosis of CG in high-risk populations.


Revista Medica De Chile | 2012

Diagnóstico de intolerancia a la lactosa en adultos: rendimiento comparativo de la clínica, test de hidrógeno espirado y test genético

Antonio Rollán; Cecilia Vial; Soledad Quesada; Karena Espinoza; Mary Hatton; Alonso Puga; Gabriela M. Repetto

BACKGROUNDnGenetically programmed adult-type hypolactasia affects 56% of Chilean population. Ideally, diagnosis should be confirmed.nnnAIMnTo compare diagnostic yield of genetic test, hydrogen (H2) expiratory test and a validated symptomatic structured survey (SS).nnnMATERIAL AND METHODSnPatients submitted to H2 test answered a historic (anamnestic) and current SS (after the ingestion of 25 g of lactose). A blood sample was obtained for determination of genetic polymorphisms C/T_13910, C/G_13907 and G/A_22018 by polymerase chain reaction. The gold standard for diagnosis of lactose intolerance (LI) was the agreement of at least two of three tests.nnnRESULTSnSixty-one participants aged 39 ± 12 years (21 males), were studied. Anamnestic SS was diagnostic of LI in all cases (score > 7), while current SS detected LI in 27/61 (46%). H2 test (an increase > 15 ppm after ingestion of 25 g of lactose) showed LI in 31/61 (51%). The locus C/G_13907 showed no polymorphism and locus G/A_22018 was in complete linkage disequilibrium with C/T_13910. Genotype C/C_13910, associated to hypolactasia, was present in 30/58 (52%). According to the gold-standard, 32/61 (52.5%) patients were diagnosed as LI. Sensitivity and specificity were, respectively, 79% and 69% for current SS, 93% and 93% for H2 test and 97% and 93% for the genetic test. The last two showed a positive likelihood ratio (LR) > 10 and a negative LR < 0.1, figures within the range considered clinically useful.nnnCONCLUSIONSnGenotype C/C_13910 is responsible for hypolactasia in this population. Anamnestic report of symptoms after milk ingestion and symptoms after lactose ingestion, are not accurate enough. H2 and genetic tests are simple and similarly accurate to diagnose lactose intolerance in adults.


Gastrointestinal Endoscopy | 2009

Single Balloon Enteroscopy: Latin America Experience

José Inácio V. Sanseverino; Jorge Landaeta; Adriana V. Safatle-Ribeiro; Juan M. Blancas Valencia; Antonio Rollán; Carla Dias; Andrea Pc de Azevedo; Paulo Sakai; Maria T. Galiano De Sanchez; Maria J. Rodriguez; Sergio Zepeda-Gómez; John Ospina


Revista Medica De Chile | 1997

Inyección intraesfinteriana de toxina botulínica en pacientes con acalasia esofágica

Zapata R; Carvajal S; Alvarez M; González R; Chianale J; Antonio Rollán


Gastrointestinal Endoscopy | 2017

Mo1167 Magnifying Image-Enhanced Endoscopy for Diagnosis of Gastric Atrophy and H. Pylori Infection in a Amerindian Population With a High-Risk of Gastric Cancer

Pablo Cortés; Antonio Rollán; Robinson G. Gonzalez; María E. Bufadel; Raúl Araya; Carolina Heredia; Arnoldo Riquelme; Enrique Bellolio; M. Villaseca; J. C. Araya; Alejandro H. Corvalán


Revista Medica De Chile | 2012

Diagnóstico de Intolerancia a la Lactosa en Adultos: Rendimiento Comparativo de la Clínica, Test Espiratorio y Test Genético

Antonio Rollán; Cecilia Vial; Soledad Quesada; Karena Espinoza; Mary Hatton; Alonso Puga; Gabriela M. Repetto


Endoscopia | 2011

Enteroscopia de un solo balón; experiencia multicéntrica latinoamericana

Jorge Landaeta; Carla Dias; José Inácio-Sanseverino; Adriana V. Safatle-Ribeiro; Maria Teresa Galiano; John Ospina-Nieto; Rafael Barreto-Zúñiga; Sergio Zepeda-Gómez; Antonio Rollán; Andrea Pc de Azevedo; Juan Manuel Blancas; Paulo Sakai

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Paulo Sakai

University of São Paulo

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Alonso Puga

Universidad del Desarrollo

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Arnoldo Riquelme

Pontifical Catholic University of Chile

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Cecilia Vial

Universidad del Desarrollo

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Karena Espinoza

Universidad del Desarrollo

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Mary Hatton

Universidad del Desarrollo

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Robinson G. Gonzalez

Pontifical Catholic University of Chile

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