Differential Diagnosis

The patient presents with a three-day history of chills, malaise, fevers, temporal headache, and elevated liver enzymes (ALT, ALP, and GGT), with negative tests for hepatitis A IgM, hepatitis B, and C antibodies. Based on these symptoms and test results, the following differential diagnoses are considered:

• Single Most Likely Diagnosis
  • Viral Hepatitis (other than A, B, C): Given the negative tests for hepatitis A, B, and C, but with symptoms and lab results suggestive of hepatitis (elevated liver enzymes), other viral hepatitis types (like hepatitis D or E, though less common in some regions) could be considered. However, hepatitis D requires co-infection or superinfection with hepatitis B, which was not detected. Hepatitis E is more likely in travelers to endemic areas or those consuming undercooked pork or wild game.
• Other Likely Diagnoses
  • Autoimmune Hepatitis: This condition can present with elevated liver enzymes and symptoms like malaise and fever. The absence of viral hepatitis markers does not rule out autoimmune hepatitis, which would require further testing (e.g., autoantibodies).
  • Drug-Induced Liver Injury (DILI): Many drugs can cause liver injury, leading to elevated liver enzymes. A thorough medication history is essential to consider this diagnosis.
  • Alcoholic Liver Disease: Although less likely given the acute presentation, alcoholic liver disease can cause elevated liver enzymes and should be considered, especially if the patient has a history of alcohol abuse.
• Do Not Miss Diagnoses
  • Wilson's Disease: A genetic disorder leading to copper accumulation in the liver, which can cause liver dysfunction and elevated liver enzymes. It's crucial to consider in young patients with liver disease of unknown etiology.
  • Budd-Chiari Syndrome: Thrombosis of the hepatic veins, which can present with acute liver dysfunction and should be considered, especially if there's a history of thrombophilia or risk factors for thrombosis.
  • Acute Bacterial Infections (e.g., Pyogenic Liver Abscess): Though less common, bacterial infections can cause liver enzyme elevation and systemic symptoms like fever and malaise.
• Rare Diagnoses
  • Toxoplasmosis: In immunocompromised patients, toxoplasmosis can cause liver enzyme elevation among other systemic symptoms.
  • Cytomegalovirus (CMV) Hepatitis: Especially in immunocompromised individuals, CMV can cause hepatitis.
  • Ischemic Hepatitis (Shock Liver): This condition occurs due to decreased blood flow to the liver and can present with elevated liver enzymes. It's often seen in critically ill patients or those with severe hypotension.

Each of these diagnoses requires careful consideration of the patient's history, physical examination, and additional diagnostic testing to determine the underlying cause of the symptoms and liver enzyme elevation.