Differential Diagnosis for Hepatocellular Dysfunction in a 17-Year-Old

Single Most Likely Diagnosis

• Non-Alcoholic Fatty Liver Disease (NAFLD)/Steatohepatitis: Given the patient's age and the pattern of liver function tests (LFTs) indicating hepatocellular dysfunction, NAFLD or steatohepatitis is a plausible diagnosis, especially if the patient has risk factors such as obesity, diabetes, or dyslipidemia.

Other Likely Diagnoses

• Viral Hepatitis: Acute or chronic viral hepatitis (e.g., hepatitis B or C) could explain the elevated ALT levels and hepatocellular dysfunction. It's essential to consider this diagnosis, especially if the patient has been exposed to viral hepatitis or has risk factors for infection.
• Drug-Induced Liver Injury: Various medications and substances can cause liver injury, leading to elevated liver enzymes. A thorough drug history, including prescription medications, over-the-counter drugs, and herbal supplements, is necessary to evaluate this possibility.
• Autoimmune Hepatitis: Although less common, autoimmune hepatitis should be considered, especially if there are other autoimmune conditions present or if the patient does not respond to initial treatments for other suspected causes.

Do Not Miss Diagnoses

• Wilson's Disease: A genetic disorder that leads to copper accumulation in the liver, causing liver damage. It's crucial to consider this diagnosis due to its potential for severe liver damage and the availability of specific treatments.
• Alpha-1 Antitrypsin Deficiency: A genetic disorder that can cause liver disease and lung disease. Early diagnosis is critical for managing the condition and preventing complications.
• Hepatitis B or C in the Context of Vertical Transmission or High-Risk Behavior: Even if less likely, missing a diagnosis of hepatitis B or C can have significant long-term consequences, including chronic liver disease and liver cancer.

Rare Diagnoses

• Glycogen Storage Diseases: Rare genetic disorders that affect the body's ability to store glycogen, leading to liver enlargement and elevated liver enzymes.
• Mitochondrial Disorders: A group of rare genetic disorders that affect the mitochondria, often presenting with multi-system involvement, including liver disease.
• Budd-Chiari Syndrome: A rare condition caused by obstruction of the hepatic veins, leading to liver enlargement, ascites, and liver dysfunction. It's essential to consider this diagnosis if there's suspicion of thrombophilia or if the patient presents with atypical liver disease symptoms.