American Board of Internal Medicine (ABIM) Certification Practice Exam

What laboratory finding suggests the presence of hepatocellular dysfunction in a patient with ascites?

1. Elevated serum bilirubin

2. Decreased serum electrolytes

3. Increased serum creatinine

4. Low total protein

The correct answer is: Elevated serum bilirubin

Elevated serum bilirubin is a key laboratory finding that indicates hepatocellular dysfunction. The liver plays a crucial role in the metabolism and excretion of bilirubin. In healthy individuals, bilirubin produced from the breakdown of hemoglobin is processed by the liver and excreted in bile. However, when liver cells are damaged or dysfunctional, this processing is impaired, leading to an accumulation of bilirubin in the bloodstream. In patients with ascites, often due to liver cirrhosis or other forms of liver disease, the presence of elevated serum bilirubin not only indicates hepatic injury but also correlates with the severity of the liver dysfunction. When bilirubin levels are high, this suggests that the liver is unable to adequately conjugate and excrete bilirubin, which is a hallmark of hepatocellular injury. The other choices do not specifically indicate hepatocellular dysfunction. Decreased serum electrolytes may reflect various other conditions, such as those related to renal function or dehydration, but are not directly linked to liver cell function. Increased serum creatinine typically points toward renal impairment rather than liver dysfunction. Low total protein could occur in a variety of settings, including protein malnutrition or chronic disease states, and while it may be seen in liver disease,