RESUMO
BACKGROUND: Many studies evaluated magnification endoscopy (ME) to correlate changes on the gastric mucosal surface with Helicobacter pylori (H. pylori) infection. However, few studies validated these concepts with high-definition endoscopy without ME. AIM: To access the association between mucosal surface pattern under near focus technology and H. pylori infection status in a western population. METHODS: Cross-sectional study including all patients referred to routine upper endoscopy. Endoscopic exams were performed using standard high definition (S-HD) followed by near focus (NF-HD) examination. Presence of erythema, erosion, atrophy, and nodularity were recorded during S-HD, and surface mucosal pattern was classified using NF-HD in the gastric body. Biopsies were taken for rapid urease test and histology. RESULTS: One hundred and eighty-seven patients were analyzed from August to November 2019. Of those, 47 (25.1%) were H. pylori+, and 42 (22.5%) had a previous H. pylori treatment. In the examination with S-HD, erythema had the best sensitivity for H. pylori detection (80.9%). Exudate (99.3%), nodularity (97.1%), and atrophy (95.7%) demonstrated better specificity values, but with low sensitivity (6.4%-19.1%). On the other hand, the absence of erythema was strongly associated with H. pylori- (negative predictive value = 92%). With NF-HD, 56.2% of patients presented type 1 pattern (regular arrangement of collecting venules, RAC), and only 5.7% of RAC+ patients were H. pylori+. The loss of RAC presented 87.2% sensitivity for H. pylori detection, 70.7% specificity, 50% positive predictive value, and 94.3% negative predictive value, indicating that loss of RAC was suboptimal to confirm H. pylori infection, but when RAC was seen, H. pylori infection was unlikely. CONCLUSION: The presence of RAC at the NF-HD exam and the absence of erythema at S-HD were highly predictive of H. pylori negative status. On the other hand, the loss of RAC had a suboptimal correlation with the presence of H. pylori.
RESUMO
The aim of this study was to present and describe the essential aspects, and to discuss the use of measures of association, relative risk and odds ratio, including formulas for calculating confidence intervals of obtained data from a cohort study of underweight live births of mothers who smoked during pregnancy, whose deliveries were performed in hospitals and maternity wards located in Campina Grande, state Pernambuco. Smoking during pregnancy was analyzed as a potential risk factor for low birth weight among 3612 newborns. In assessing the association of outcome, there were no large numeric differences between the estimates of the relative risk, odds ratios and confidence intervals obtained. It is an acceptable approximation to the relative risk and the odds ratio. It is up to the researcher to choose the most appropriate technique to its subject matter and should be determined according to the surveyed data.
O objetivo deste estudo foi apresentar e descrever os aspectos essenciais, bem como discutir a utilização das medidas de associação, risco relativo e razão de chances, incluindo fórmulas para o cálculo de intervalos de confiança de dados obtidos por meio de um estudo de coorte realizado com nascidos vivos de baixo peso de mães que fumaram durante a gravidez, cujos partos foram realizados em hospitais e maternidades localizados em Campina Grande, Pernambuco. O hábito de fumar durante a gravidez foi analisado como um potencial fator de risco para o baixo peso ao nascer entre 3612 recém nascidos. Na avaliação do desfecho de associação, não se observaram grandes diferenças numéricas entre as estimativas do risco relativo, da razão de chances e do intervalo de confiança obtidos. É uma aproximação aceitável para o risco relativo e para a razão de chances. Cabe ao pesquisador a escolha da técnica mais adequada ao seu objeto de estudo, devendo ser determinada de acordo com os dados pesquisados.
