Typhoid fever is an infection caused by Salmonella Typhi bacteria, manifesting with symptoms such as fever, diarrhea, and vomiting. If not diagnosed early and treated appropriately, it can lead to serious complications. Possible complications include: Internal bleeding, intestinal perforation, gallbladder inflammation (cholecystitis), bronchitis, pneumonia and other respiratory problems, myocarditis (inflammation of the heart muscle), osteomyelitis (inflammation of the bone), kidney failure.