If Salmonella typhi enters the bloodstream from the small intestine, what is the first major organ it would encounter?

Salmonella typhi, the bacterium responsible for typhoid fever, typically enters the bloodstream from the small intestine following infection. After traversing the intestinal wall, pathogens usually enter the mesenteric veins, which drain into the hepatic portal vein. This vein carries blood directly to the liver, serving as the first major organ that the bacteria encounter after they have entered the circulatory system.

In the liver, these bacteria can replicate and contribute to systemic infection if not effectively cleared by the immune system. This connection between the intestinal veins and the liver through the hepatic portal system is critical in understanding how certain pathogens spread within the body after initial intestinal colonization. The liver plays a central role in filtration and processing of blood from the digestive tract, making it the primary point of contact following intestinal absorption for pathogens entering the bloodstream.