<prompt> A person returns to Delhi from Bangladesh after 2 days and has diarrhoes. Stool examination shows RBCs in stool. The likely organism causing is ?Enteropathogenic E. ColiEnterotoxigenic E. ColiSalmonella typhiShigella dysenteriae  <response>: Ans. is d i.e., Shigella dysenteriae . This is a case of travellers diarrhea. . RBCs in stool are suggestive of dysentry. Lets see each option sequentially: . Enteropathogenic E. coli is not a cause of travellers diarrhea . Enterotoxigenic E. coli is the most common cause of travellers diarrhea but it causes watery diarrhea, not dysentry. . Salmonella other than S. typhi causes gastroenteritis. . Shigella is a cause of travellers diarrhea and it causes dysentry. 