Differential Diagnosis

The patient presents with flu-like symptoms, elevated liver enzymes, and a lingular infiltrate. The following differential diagnoses are considered:

• Single most likely diagnosis
  • Viral pneumonia: The patient's flu-like symptoms, lingular infiltrate, and negative respiratory biofire suggest a viral etiology. The elevated liver enzymes could be due to a viral hepatitis or a systemic inflammatory response.
• Other Likely diagnoses
  • Atypical bacterial pneumonia: The patient's symptoms and laboratory results could also be consistent with an atypical bacterial pneumonia, such as Mycoplasma or Legionella.
  • Influenza: Although the respiratory biofire is negative, influenza can cause a false-negative result, especially if the sample is not collected properly.
  • Hepatic involvement in a systemic infection: The elevated liver enzymes could be due to a systemic infection, such as sepsis or a viral infection, affecting the liver.
• Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
  • Sepsis: Although the patient's lactic acid is within normal limits, sepsis can present with elevated liver enzymes and respiratory symptoms.
  • Pulmonary embolism: The patient's symptoms and laboratory results could be consistent with a pulmonary embolism, especially if the CT abdomen and pelvis was done to rule out other causes of embolism.
  • Hepatic vascular occlusion: The elevated liver enzymes and negative CT abdomen and pelvis could suggest a hepatic vascular occlusion, such as Budd-Chiari syndrome.
• Rare diagnoses
  • Autoimmune hepatitis: The patient's elevated liver enzymes could be due to an autoimmune hepatitis, although this would be an unusual presentation.
  • Wilson's disease: The patient's elevated liver enzymes and respiratory symptoms could be consistent with Wilson's disease, although this would be a rare diagnosis.
  • Lymphoma: The patient's symptoms and laboratory results could be consistent with a lymphoma, especially if the lingular infiltrate is due to lymphomatous involvement of the lung.