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BACKGROUND: Rectal bleeding is the most important symptom of intestinal neoplasia; thus, tests of occult blood detection in stools are widely used for pre neoplastic lesions and colorectal cancer (CRC) screening. OBJECTIVE: Evaluate the accuracy of OC-Sensor quantitative test (Eiken Chemical, Tokyo, Japan) at cut-off 10 µg Hb/g feces (50 ng/mL) in a cohort of subjects that had to undergo diagnostic colonoscopy, and if more than one sample collected in consecutive days would improve the diagnostic accuracy of the test. METHODS: Patients (mean age 56.3±9.7 years) that underwent colonoscopy prospectively randomly received one (1-sample FIT, FIT 1) or two (2-sample FIT, FIT 2) collection tubes. They collected the stool sample before starting colonoscopy preparation. Samples were analyzed by the OC-Auto Micro 80 (Eiken Chemical, Tokyo, Japan). The performance of FIT 1 and FIT 2 were compared to the colonoscopy findings. RESULTS: Among 289 patients, CRC was diagnosed in 14 (4.8%), advanced adenoma in 37 (12.8%), early adenoma in 71 (24.6%) and no abnormalities in 141 (48.8%). For FIT 1, the sensitivity for CRC was 83.3% (95%CI 36.5-99.1%), for advanced adenoma was 24% (95%CI 10.1-45.5%), with specificity of 86.9% (95%CI 77.3-92.9%). For FIT 2, the sensitivity for CRC was 75% (95%CI 35.6-95.5%), for advanced adenoma was 50% (95%CI 22.3-77.7%), with specificity of 92.9% (95%CI 82.2-97.7%). The positive likelihood ratios were 1.8 (95%CI 0.7-4.4 for FIT 1) and 7.1 (95%CI 2.4-21.4 for FIT 2) for advanced adenoma, and 6.4 (95%CI 3.3-12.3, for FIT 1) and 10.7 (95%CI 3.8-29.8, for FIT 2) for CRC. The negative likelihood ratio were 0.9 (95%CI 0.7-1, for FIT 1) and 0.5 (95%CI 0.3-0.9, for FIT 2) for advanced adenoma, and 0.2 (0.03-1.1, for FIT 1) and 0.3 (0.08-0.9, for FIT 2) for CRC. The differences between FIT 1 and FIT 2 performances were not significant. However, the comparison of the levels of hemoglobin in feces of patients of FIT 1 and FIT 2 showed that the differences between no polyp group and advanced adenoma and CRC were significant. CONCLUSION: The accuracy of OCR Sensor with 10 µg Hb/g feces cut-off was comparable to other reports and two-sample collection improved the detection rate of advanced adenoma, a pre neoplastic condition to prevent CRC incidence. RESUMO CONTEXTO: Sangramento retal é o sintoma mais importante de neoplasia intestinal; portanto, testes para detecção de sangue oculto nas fezes são amplamente usados para rastreamento de lesões pré-neoplásicas e de câncer colorretal (CCR). OBJETIVO: Avaliar a acurácia do teste quantitativo OC-Sensor (Eiken Chemical, Tokyo, Japan) com o valor de corte de 10 µg Hb/g fezes (50 ng/mL) numa coorte de indivíduos que se submeteram à colonoscopia diagnóstica, e se mais de uma amostra coletada em dias consecutivos melhoraria a acurácia diagnóstica do teste. MÉTODOS: Pacientes (idade média 56,3±9,7 anos) que se submeteram à colonoscopia prospectivamente, randomicamente, receberam tubos de coleta: um (1-amostra FIT, FIT 1), ou dois (2-amostra FIT, FIT 2). Eles coletaram as amostras de fezes antes de iniciar o preparo da colonoscopia. As amostras foram analisadas pelo OC-Auto Micro 80 (Eiken Chemical, Tokyo, Japan). As performances do FIT 1 e do FIT 2 foram comparadas com os achados da colonoscopia. RESULTADOS: Entre 289 pacientes, CCR foi diagnosticado em 14 (4,8%), adenoma avançado em 37 (12,8%), adenoma precoce em 71 (24,6%) e sem anormalidades em 141 (48,8%). Para FIT 1, a sensibilidade para CCR foi 83,3% (95%IC 36,5-99,1%), para adenoma avançado foi 24% (95%IC 10,1-45,5%), com especificidade de 86,9% (95%IC 77,3-92,9%). Para FIT 2, a sensibilidade para CCR foi 75% (95%IC 35,6-95,5%), para adenoma avançado foi 50% (95%IC 22,3-77,7%), com especificidade de 92,9% (95%IC 82,2-97,7%). A razão de verossimilhança positiva foi 1,8 (95%IC 0,7-4,4 para FIT 1) e 7,1 (95%IC 2,4-21,4 para FIT 2) para adenoma avançado, e 6,4 (95%IC 3,3-12,3, para FIT 1) e 10,7 (95%IC 3,8-29,8, para FIT 2) para CCR. A razão de verossimilhança negativa foi 0,9 (95%IC 0,7-1, para FIT 1) e 0,5 (95%IC 0,3-0,9, para FIT 2) para adenoma avançado, e 0,2 (0,03-1,1, para FIT 1) e 0,3 (0,08-0,9, para FIT 2) para CCR. As diferenças de performance entre FIT 1 e FIT 2 não foram significantes. Entretanto, a comparação dos níveis de hemoglobina nas fezes dos pacientes de FIT 1 e FIT 2 mostraram que as diferenças entre sem pólipo e adenoma avançado e CCR foram significantes. CONCLUSÃO: A acurácia do OCR Sensor com valor de corte de 10 µg Hb/g de fezes foi comparável a outras publicações e a coleta de duas amostras melhorou a taxa de detecção de adenoma avançado, lesão pré-neoplásica, para prevenir CCR.

Objectives The stool antigen assay for H. pylori infection diagnosis with monoclonal antibodies is a simple and recommended technique by the Maastricht V/Florence consensus report. Recently, Pylori K-Set K-1219 (Coris Bioconcept Sprl, Belgium) and HP-F23 (Symbiosys, Brazil) have been made commercially available in Brazil. Thus, the aim of this study was to evaluate the diagnostic accuracies of these two rapid stool antigen tests by immunochromatographic assays (index tests) for the clinical practice. Design and methods A total of 98 patients who underwent upper gastrointestinal endoscopy and 13 C-urea breath test entered the study. H. pylori infection status was defined by the combination of the rapid urease test and the 13 C-urea breath test (reference standard). Two observers who were aware of H. pylori status performed the reading of index tests. Diagnostic accuracy (sensitivity, specificity, positive predictive value, negative predictive value with 95% confidence intervals, positive likelihood ratio, negative likelihood ratio and kappa index measure of agreement) were determined. Results The index tests where in perfect agreement with the H. pylori status with kappa values of 0.87 for Pylori K-Set K-1219 and 0.92 for HP-F23. The sensitivity of HP-F23 was 97.9% (IC95%: 87.5–100) and specificity was 93.8% (IC95%; 84–97.2).The positive likelihood ratio was 15.8, and the negative likelihood ratio was 0.02. The Pylori K-Set K-1219 had a sensitivity of 87.7% (IC95%: 74.5–94.9) and a specificity of 100% (IC95%: 91.6–100); the positive likelihood ratio was ∞, and the negative likelihood ratio was 0.1. The test line on the cassette device of HP-F23 was stronger than of the Pylori K-Set K-1219. Conclusion The HP-F23 test performed better in clinical practice. Nonetheless, the 13 C-urea breath test is more reliable technique. Moreover, caution must be paid to the trace or clear pale test line readings that were observed in false positive and false negative results, leading to incorrect management of the patient.

AIM To assess lactase gene (LCT)-13910C>T polymorphisms in Brazilian non-alcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH) patients in comparison with healthy controls. METHODS This was a transverse observational clinical study with NAFLD patients who were followed at the Hepatology Outpatient Unit of the Hospital das Clinicas, Sao Paulo, Brazil. The polymorphism of lactase non-persistence/lactase persistence (LCT-13910C>T) was examined by PCR-restriction fragment length polymorphism technique in 102 liver biopsy-proven NAFLD patients (steatosis in 9 and NASH in 93) and compared to those of 501 unrelated healthy volunteers. Anthropometric, clinical, biochemical and liver histology data were analyzed. Continuous variables were compared using the t or Mann-Whitney tests, and categorical data were compared with the Fisher's exact test. Univariate logistic regression and multivariate logistic regression adjusted for gender and age were performed. RESULTS No differences in the LCT-13910 genotype frequencies were noted between the NAFLD patients (66.67% of the patients with steatosis were CC, 33.33% were CT, and none were TT; 55.91% of the patients with NASH were CC, 39.78% were CT, and 4.3% were TT; P = 0.941) and the healthy controls (59.12% were CC, 35.67% were CT, and 5.21% were TT) or between the steatosis and NASH patients. That is, the distribution of the lactase non-persistence/lactase persistence polymorphism (LCT-13910C>T) in the patients with NAFLD was equal to that in the general population. In the NASH patients, the univariate analysis revealed that the lactase non-persistence (low lactase activity or hypolactasia) phenotype was associated with higher insulin levels (23.47 ± 15.94 μU/mL vs 15.8 ± 8.33 μU/mL, P = 0.027) and a higher frequency of insulin resistance (91.84% vs 72.22%, P = 0.02) compared with the lactase persistence phenotype. There were no associations between the LCT genotypes and diabetes (P = 0.651), dyslipidaemia (P = 0.328), hypertension (P = 0.507) or liver histology in these patients. Moreover, in the NASH patients, hypolactasia was an independent risk factor for insulin resistance even after adjusting for gender and age [OR = 5.0 (95%CI: 1.35-20; P = 0.017)]. CONCLUSION The LCT-13910 genotype distribution in Brazilian NAFLD patients was the same as that of the general population, but hypolactasia increased the risk of insulin resistance in the NASH patients.

Context Fecal elastase is a noninvasive test for pancreatic insufficiency diagnosis. Objectives Evaluate the usefulness of fecal elastase 1 for the indication of exocrine pancreatic insufficiency among former alcohol addicts and patients with chronic pancreatitis. Methods Forty-three patients with chronic pancreatitis and thirty-three asymptomatic former alcohol addicts entered the study. The levels of fecal elastase 1 were measured using a commercial kit. Pancreatic imaging findings were used to categorize the groups. Results The levels of fecal elastase 1 were significantly lower in the patients than in the former alcohol addicts and in the group with tissue calcifications, duct alterations, or atrophy. With a cutoff level of 100 μg/g, the sensitivity of fecal elastase 1 in chronic pancreatitis was 46.51% and its specificity was 87.88% with a positive predictive value of 83.33% and a negative predictive value of 55.77%. When patients were stratified according to the severity of their pancreatitis, the sensitivity was 6.25% for mild pancreatitis and 70.37% for marked pancreatitis. Conclusion Low level of fecal elastase 1 was associated with marked rather than mild chronic pancreatitis; however, it may be useful to indicate pancreatic exocrine insufficiency in asymptomatic former alcohol addicts. Contexto O teste de elastase fecal é um teste não invasivo para diagnosticar insuficiência pancreática. Objetivos Avaliar a utilidade da elastase fecal 1 como indicador de insuficiência pancreática entre ex alcoólatras e pacientes com pancreatite crônica. Métodos Quarenta e três pacientes com pancreatite crônica e 33 ex alcoólatras assintomáticos entraram no estudo. Os níveis de elastase fecal 1 foram medidos usando kit comercial. Os achados de imagem pancreática foram usados para categorizar os grupos. Resultados Os níveis de elastase fecal 1 foram significantemente menores nos pacientes que nos ex alcoólatras e no grupo com calcificações teciduais, alterações de ductos, ou atrofia. A sensibilidade da elastase fecal 1 na pancreatite crônica foi de 46,51% e a especificidade foi de 87,88%, com valor preditivo positivo de 83,33% e valor preditivo negativo de 55,77%. Quando os pacientes foram estratificados segundo a severidade da pancreatite, a sensibilidade foi de 6,25% para pancreatite crônica leve e 70,37% para pancreatite crônica severa. Conclusão Baixo nível de elastase fecal foi associado com pancreatite crônica severa mais do que com a leve; entretanto, pode ser útil para indicar insuficiência pancreática exócrina entre os ex alcoólatras.