This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Peptic Ulcer Disease, Subject name: Medicine
[{'content': 'Most sensitive non invasive test for diagnosis of H pylori? \nSelect and explain. \nA. Rapid urease test, B. Demonstration of organism in gastric biopsy, C. Breath urea test, D. ELISA', 'role': 'user'}, {'content': 'Answer: C \nExplanation: ELISA test has sensitivity of 80% and has been replaced by C-13 urea breath test and fecal antigen immunoassay. Both have sensitivity of >90%. Hence though rapid urease test is having a comparable sensitivity and higher specificity, it is an invasive test. Sensitivity of various diagnosis tests Test Sensitivity in % Rapid urease (INVASIVE) 80-95 Histology 80-90 Serology >80 Urea breath test (NON INVASIVE) >90 Stool antigen >90 In assessment of response to treatment, non-invasive tests are preferred. Breath urea test will be done but can be false negative if done within 4 weeks of antibiotic treatment. High levels of interleukin 1,2,6 & 8 and TNFa,IFN gamma in the gastric epithelium are found.', 'role': 'assistant'}]