Differential Diagnosis for Elevated Liver Enzymes
The patient presents with mildly elevated AST and ALT levels, normal bilirubin, and a normal CBC. Here's a categorized differential diagnosis:
- Single Most Likely Diagnosis
- Non-alcoholic fatty liver disease (NAFLD): This condition is increasingly common in young adults and can cause mild elevations in liver enzymes. The patient's age and the absence of other symptoms or abnormalities make this a plausible diagnosis.
- Other Likely Diagnoses
- Viral hepatitis: Although the patient's liver enzyme elevations are mild, viral hepatitis (such as hepatitis A, B, or C) can cause similar laboratory findings. Further testing for hepatitis serologies would be necessary to confirm this diagnosis.
- Alcoholic liver disease: Although less likely in a 20-year-old, it's essential to consider alcoholic liver disease, especially if the patient consumes alcohol. A thorough history of alcohol use would help assess this possibility.
- Medication-induced liver injury: Various medications, including over-the-counter drugs and supplements, can cause liver enzyme elevations. A detailed medication history is crucial to evaluate this possibility.
- Do Not Miss Diagnoses
- Wilson's disease: This rare genetic disorder can cause liver enzyme elevations and would be catastrophic if missed. Although unlikely, it's essential to consider Wilson's disease, especially in young patients with unexplained liver enzyme elevations.
- Autoimmune hepatitis: This condition can cause liver inflammation and enzyme elevations, and prompt treatment is necessary to prevent liver damage. Although less common, autoimmune hepatitis should be considered in the differential diagnosis.
- Alpha-1 antitrypsin deficiency: This genetic disorder can cause liver disease and would be critical to diagnose to prevent long-term liver damage.
- Rare Diagnoses
- Celiac disease: This autoimmune disorder can cause liver enzyme elevations, although it's a less common cause. Celiac disease would be considered if the patient has gastrointestinal symptoms or other signs suggestive of the condition.
- Hemochromatosis: This genetic disorder causes iron overload, which can lead to liver damage and enzyme elevations. Although rare, hemochromatosis should be considered in patients with unexplained liver enzyme elevations, especially if they have a family history of the condition.
- Glycogen storage diseases: These rare genetic disorders can cause liver enzyme elevations and would be considered if the patient has other symptoms or signs suggestive of a glycogen storage disease.