PAEA Surgery End Of Rotation (EOR) Practice Exam

Which is the most common gram-negative bacteria associated with cholangitis?

1. Staphylococcus

2. Escherichia coli

3. Streptococcus

4. Clostridium

The correct answer is: Escherichia coli

In the context of cholangitis, Escherichia coli is recognized as the most common gram-negative bacterium involved in this condition. Cholangitis is an infection of the biliary tract, typically arising from an obstruction that promotes bacterial growth within the bile duct system. E. coli is a part of the normal intestinal flora and can easily enter the biliary system, especially in cases where there is a disruption like bile duct obstruction due to gallstones or strictures. The predominance of E. coli in cholangitis can be attributed to its ability to survive in the anaerobic environment of the obstructed bile ducts and its virulence factors that promote adherence and invasion. Furthermore, because E. coli is highly resilient and adaptable, it is a frequent isolate in cases of urinary tract infections and other intra-abdominal infections, correlating with its role in cholangitis manifestations. In contrast, other bacteria listed are either gram-positive or are not typically associated with this specific type of infection. Staphylococcus and Streptococcus are mainly gram-positive organisms and less frequently implicated in cholangitis. Clostridium is also not associated with cholangitis but rather tends to be involved in different types of infections, such as those linked to necrot