Cell Injury Case Studies


CASE 1: Hepatic Steatosis with Alcoholism


Clinical History:

A 50-year-old man has become increasingly lethargic over the past 3 months. During that time he has had one DUI conviction. On physical examination, his abdomen appears enlarged and there is a fluid wave. He has pitting edema to his knees. He has very mild scleral icterus. A CBC shows that he has a Hgb of 11.1 g/dL with a normal WBC count and platelet count. A review of the peripheral blood smear shows that the RBC's are larger than normal (macrocytosis). Serum chemistries shows sodium 135 mmol/L, potassium 3.7 mmol/L, chloride 96 mmol/L, CO2 23 mmol/L, creatinine 1.3 mg/dL, urea nitrogen 22 mg/dL, glucose 50 mg/dL, total protein 5.5 g/dL, albumin 2.9 g/dL, alkaline phosphatase 40 U/L, AST 65 U/L, ALT 58 U/L, total bilirubin 4.2 mg/dL, and direct bilirubin 3.3 mg/dL.
  1. What form of cellular injury has occurred here?

    2. This is steatosis, or fatty metamorphosis, of the liver. Many hepatocytes contain a large droplet of lipid (which is clear with routine tissue processing and H&E staining).

  2. How do you explain the physical examination findings?

    3. The fluid wave is due to fluid collecting in the peritoneal cavity, known as ascites. The pitting edema is due to fluid collecting in soft tissues. When liver function begins to fail and albumin begins to drop, then colloid osmotic pressure is lowered and fluid begins to collect extravascularly. In persons who spend most of the day upright, then the fluid will collect in the most dependent area (lower extremities). Bedridden patients may have presacral edema. His scleral icterus is due to increased bilirubin.

  3. How do you explain the CT findings?

    4. The liver is enlarged (hepatomegaly). The attenuation of the liver is lower (darker) than that of normal, because fat tends to be darker.

  4. What is the significance of the findings with the CBC?

    5. He has an anemia. Since the RBC's are large, this is a "macrocytic" form of anemia. This is common in persons with chronic liver disease, since the lipoprotein metabolism and cholesterol synthesis (cell membranes have lipids) is altered.

  5. What is the patient's underlying problem?

    6. He probably has excessive consumption of ethanol, which is toxic to liver.

  6. Explain the pharmacokinetics of this problem.

    7. Ethanol is metabolized by alcohol dehydrogenase in the liver. This metabolism proceeds by "zero order" kinetics-that is, the amount of alcohol metabolized occurs at a constant rate. Drinking more alcohol over a shorter time means that the blood alcohol concentration will rise. The legal limit is 0.08 gm% (80 mg/dL). He exceeded this on at least one occasion.