RESUMO
El cultivo de Helicobacter pylori es indispensable para estudiar la sensibilidad de las cepas a distintos agentes antimicrobianos, realizar pruebas diagnósticas y evaluar su toxicidad y virulencia, además, preservar los aislamientos con fines inve stigati vos futuros. Bajo condiciones óptimas, el cultivo posee una sensibilidad cercana al 90% y una especificad de 100%, pero las tasas de aislamiento de los individuos infectados pueden variar entre 23,5% a 97%, dependiendo de un número de factores como los componentes del medio de cultivo, el transporte de las biopsias, automedicación con inhibidores de bomba de protones/antibióticos y los métodos de toma de la biopsia. Por esta razón, el objetivo del estudio de la investigación fue comparar diferentes medios de cultivo y las condiciones de transporte, manejo y procesamiento de las biopsias para el aislamiento de Helicobacter pylori. Se analizaron 27 biopsias gástricas de antro y cuerpo del estómago obtenidas de pacientes dispépticos; fueron sembradas por duplicado en tres medios de cultivo diferentes designados como A, B y C y bajo dos condiciones de siembra de la biopsia por Impresión (Touch) y por maceración, el transporte de las biopsias se realizó en medio de transporte con y sin suplementos y antibióticos. Los resultados de la tasa de recuperación en el medio de cultivo A fue 59,2%, en el B fue 37% y en el C fue de 18,5%. Tanto el medio A como en el B se evidenció un crecimiento vigoroso de H. pylori, caso contrario en el medio de cultivo C, en donde las colonias no se observaron tan brillantes y evidentes. La siembra por maceración en laboratorio y el medio de cultivo A proporcionaron las mejores condiciones para la recuperación de H. pylori.
Helicobacter pylori cultivation is essential to study the sensitivity of isolates to various antimicrobial agents, diagnostic testing and evaluating toxicity and virulence also preserve isolates with future research purposes. Under optimum conditions, cultivation has a sensitivity approaching 90% and a specificity of 100%, but the rates of isolation of infected individuals may vary between 23.5% to 97%, depending on a number of factors such as components culture medium, transporting biopsies, self-medication with proton-pump inhibitor / antibiotics and methods of making the biopsy. For this reason, the aim of the research study was to compare different culture media and conditions of transport, handling and processing of biopsies for the isolation of Helicobacter pylori. 27 antrum's gastric biopsies and body 's gastric biopsies obtained from dyspeptic patients were analyzed; were seeded for duplicate on three different culture's mediums designated as A, B and C and under two culture's conditions. The biosies were seeded for Printing (Touch) in the endoscopy unit and maceration in the microbiology's laboratory. The biopsies were transported in transport medium with and without supplements and antibiotics. The results of the recovery rate in the culture medium A was 59.2%, in the B was 37% and in the C was 18.5%. In the culture médium A and B were observed a vigorous growth of H. pylori, otherwise in the culture medium C, the colonies were not observed as bright. Seeding by maceration in laboratory culture medium and A provided the best conditions for recovery of H. pylori.
Assuntos
Humanos , Estômago , Biópsia , Helicobacter pylori , Anti-Infecciosos , Antibacterianos , Automedicação , Triacetonamina-N-Oxil , Virulência , Sensibilidade e Especificidade , Endoscopia , MicrobiologiaRESUMO
BACKGROUND: Helicobacter pylori antimicrobial resistance rates differ among countries and even between different areas of a country. In Colombia, the most commonly used antimicrobials for the treatment of H pylori infection are amoxicillin, clarithromycin and metronidazole. AIM: To determine antimicrobial susceptibility of H pylori strains isolated in Colombia. MATERIALS AND METHODS: Eighty eight strains of H pylori were isolated and identified by microbiological methods and confirmed with polymerase chain reaction (PCR). The detection of antimicrobial resistance to amoxicillin, clarithromycin, metronidazole and tetraclycline, was conducted by the Etest method. Mutations in the 23S rDNA, involved in resistance to clarithromycin, were detected using PCR and restriction fragment length polymorphism. RESULTS: Eighty eight and 2.2% of the strains were resistant to metronidazole and clarithromycin, respectively. No isolate was simultaneously resistant to amoxicillin or tetracycline. The two clarithromycin resistant strains were homozygous for the A2143G mutation. No mutations were found in the remaining 86 susceptible strains. CONCLUSIONS: The high rate of metronidazole resistance in our population precludes the use of this drug for the empirical treatment of H pylori infection.
Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana/genética , Infecções por Helicobacter/microbiologia , Helicobacter pylori/efeitos dos fármacos , Metronidazol/farmacologia , Antibacterianos/classificação , Colômbia/epidemiologia , DNA Ribossômico/efeitos dos fármacos , DNA Ribossômico/genética , Farmacorresistência Bacteriana/efeitos dos fármacos , Infecções por Helicobacter/tratamento farmacológico , Infecções por Helicobacter/epidemiologia , Helicobacter pylori/genética , Humanos , Testes de Sensibilidade Microbiana/métodos , Mutação/efeitos dos fármacos , Mutação/genéticaRESUMO
Background: Helicobacter pylori antimicrobial resistance rates differ among countries and even between different areas of a country. In Colombia, the most commonly used antimicrobials for the treatment of H pylori infection are amoxicillin, clarithromycin and metronidazole. Aim: To determine antimicrobial susceptibility of H pylori strains isolated in Colombia. Materials and methods: Eighty eight strains of H pylori were isolated and identified by microbiological methods and confirmed with polymerase chain reaction (PCR). The detection of antimicrobial resistance to amoxicillin, clarithromycin, metronidazole and tetraclycline, was conducted by the Etest method. Mutations in the 23S rDNA, involved in resistance to clarithromycin, were detected using PCR and restriction fragment lenght polymorphism. Results: Eighty eight and 2.2 percent of the strains were resistant to metronidazole and clarithromycin, respectively. No isolate was simultaneously resistant to amoxicillin or tetracycline. The two clarithromycin resistant strains were homozygous for the A2143G mutation. No mutations were found in the remaining 86 susceptible strains. Conclusions: The high rate of metronidazole resistance in our population precludes the use of this drug for the empirical treatment of Hpylori infection.
Assuntos
Humanos , Antibacterianos/farmacologia , Farmacorresistência Bacteriana/genética , Infecções por Helicobacter/microbiologia , Helicobacter pylori/efeitos dos fármacos , Metronidazol/farmacologia , Antibacterianos/classificação , Colômbia/epidemiologia , DNA Ribossômico/efeitos dos fármacos , DNA Ribossômico/genética , Farmacorresistência Bacteriana/efeitos dos fármacos , Infecções por Helicobacter/tratamento farmacológico , Infecções por Helicobacter/epidemiologia , Helicobacter pylori/genética , Testes de Sensibilidade Microbiana/métodos , Mutação/efeitos dos fármacos , Mutação/genéticaRESUMO
Resistance to metronidazole, clarithromycin, and amoxicillin (amoxicilline) was found in 82, 3.8, and 1.9% of 106 Helicobacter pylori isolates, respectively. No tetracycline-resistant isolates were found. In all of the clarithromycin-resistant isolates, only one point mutation was present, either A2143G or A2142G. Our results indicate that metronidazole should not be included in the empirical treatment of H. pylori infection in this region.
Assuntos
Antibacterianos/farmacologia , Claritromicina/farmacologia , Infecções por Helicobacter/microbiologia , Helicobacter pylori/efeitos dos fármacos , Amoxicilina/farmacologia , Colômbia , Farmacorresistência Bacteriana/genética , Helicobacter pylori/genética , Humanos , Metronidazol/farmacologia , Testes de Sensibilidade Microbiana , Reação em Cadeia da Polimerase , Tetraciclina/farmacologiaRESUMO
Objetivo: Comparar el índice de desempeño de los métodos de diagnóstico de rutina y la PCR para establecer por definición de caso la prevalencia de infección por H. pylori en pacientes con enfermedad acido-péptica en Quindío. Metodología: A 73 pacientes se les tomaron seis biopsias de cada uno, una antral para la PCR-ureC, tres para cultivo (antral, cuerpo y fondo gástricos), otra antral para prueba rápida de ureasa (PRU) y ésta junto con una del cuerpo para el examen histológico. Se determinó el índice de desempeño de cada uno de los métodos. Para el diagnóstico decisivo de la infección se consideró como definición de caso (H. pylori positivo) el cultivo positivo o la concordancia de por lo menos dos métodos de diagnósticos positivos (examen histológico, PRU y PCR). Resultados: El examen histológico del antro fue positivo en 79.5% (58/73) y en cuerpo 82.2% (60/73); la combinación de los resultados de las dos biopsias del estudio histológico fue 94.5% (69/73). Los cultivos de las tres biopsias mostraron idéntico resultado en 75.4% (55/73); la combinación de los resultados del cultivo en las tres biopsias fue 86.3% (63/73). La PRU en biopsia antral fue positiva en 79.5% (58/73) y la PCR-ureC de biopsia antral fue 86.3% (63/73). De acuerdo con la definición de caso la prevalencia de la infección por H. pylori fue 97.3 % (71/73). Al comparar los resultados de cada método frente al obtenido por definición de caso, el examen histológico, el cultivo, la PCR y PRU presentaron 2, 8, 8, y 13 falsos negativos, respectivamente, pero no hubo falsos positivos. Los índices de desempeño (ID) para cada método fueron: Cultivo: ID, 78.1% y 88.7% de sensibilidad, resultado idéntico para las tres biopsias (antral, cuerpo y fondo); PRU: ID, 82.2% y sensibilidad 81.7%. Examen histológico: ID, 87.0% y sensibilidad 86.6%, en la biopsia antral e ID, 89.9% en cuerpo y sensibilidad 90.9%. Y la PCR-ureC con ID. 89.0% y sensibilidad 88.7%.
Introduction: Helicobacter pylori is a gramnegative bacterium that colonizes the gastric mucosa, and infects more than half of the worldwide population, causing gastritis and ulcer-peptic disease and being associated with gastric carcinoma and gastric lymphoma (MALT). Objective: To compare the performance index of techniques of routine diagnosis and PCR in order to establish by case definition the prevalence of infection by H. pylori in patients with gastroduodenal disease in Quindío. Methodology: In 73 patients were taken six biopsies. One antral for the PCR-ureC, three for culture (antral, body and fundus), other antral for rapid urease test (RUT). The previous were united to one of the body for histological examination. The performance index was established for each of the methods. For definitive diagnosis of the infection we used the case definition (positive H pylori) was used: A patient was classified as H. pylori positive with isolation of bacteria in culture or based on the agreement of at least two positive tests (histological examination, RUT and PCR). Results: The histological examination was positive 79.5% (58/73) in antral biopsy and in body 82.2% (60/73) and the combination of both biopsies was 94.5% (69/73). Culture assessment in the three biopsies showed identical results, 75.4% (55/73) and by combination all biopsies were 86.3% (63/73). The RUT in antral biopsy was 79.5% (58/73) and for PCR-ureC of antral biopsy was 86.3% (63/73). The prevalence for H pylori infection was 97.3% (71/ 73) in accordance with the case definition. The comparison of the results of each method in front of the result by case definition, the histological examination, culture, PCR and RUT presented 2, 8, 8, and 13 false negative in their order and none presented false positives. Performance indexes (PI) for each method were: Culture, 78.1% with sensibility, 88.7%, and identical results in three biopsies. The RUT, had 82.2% and 81.7% of sensibility.
