American Board of Internal Medicine (ABIM) Certification Practice Exam

What condition can develop due to long-term decreased bile acid secretion in patients with primary biliary cholangitis?

1. Fat-soluble vitamin deficiencies

2. Iron deficiency anemia

3. Hyperkalemia

4. Vitamin B12 deficiency

The correct answer is: Fat-soluble vitamin deficiencies

In patients with primary biliary cholangitis, long-term decreased bile acid secretion can lead to malabsorption of fat. Bile acids are essential for the emulsification and absorption of dietary fats and fat-soluble vitamins, which include vitamins A, D, E, and K. When bile acid secretion is impaired, the absorption of these vitamins is significantly affected, leading to potential deficiencies over time. Fat-soluble vitamin deficiencies can result in a range of health issues. For example, a deficiency in vitamin A may lead to vision problems, while a lack of vitamin D can cause bone malformations and contribute to osteoporosis. Deficiencies in vitamin E can affect neurological function, and vitamin K deficiency can lead to coagulopathies. In contrast, the other conditions listed do not directly result from decreased bile acid secretion. For instance, iron deficiency anemia typically arises from inadequate iron intake, chronic blood loss, or malabsorption unrelated to bile acids. Hyperkalemia refers to elevated potassium levels, which can occur due to various factors, including kidney dysfunction, rather than bile acid levels. Vitamin B12 deficiency is often associated with malabsorption conditions like pernicious anemia or certain gastrointestinal disorders but is less directly linked to bile acid secretion. Thus,