Differential Diagnosis for Cutaneous Manifestations

Given the patient's history of hepatocellular carcinoma, increased bilirubin, obstructive jaundice, itching, and recent initiation of chemotherapy, the following differential diagnoses are considered:

• Single Most Likely Diagnosis
  • Pruritus secondary to obstructive jaundice: This is a common symptom in patients with obstructive jaundice due to the buildup of bile salts in the skin, leading to intense itching.
• Other Likely Diagnoses
  • Drug eruption due to chemotherapy: Many chemotherapy agents can cause skin reactions, including rashes, itching, and other cutaneous manifestations.
  • Fungal infections: Immunocompromised patients, such as those undergoing chemotherapy, are at increased risk for fungal infections, which can present with skin lesions.
  • Cholestasis-associated pruritus: This condition is directly related to the patient's liver disease and can cause severe itching.
• Do Not Miss Diagnoses
  • Jaundice-associated xanthomas: These are skin lesions associated with high levels of bilirubin and can be a sign of severe liver disease.
  • Paraneoplastic pemphigus: A rare autoimmune disorder associated with certain types of cancer, including hepatocellular carcinoma, which can cause severe skin blistering.
  • Sepsis-related skin lesions: In immunocompromised patients, sepsis can manifest with skin lesions, which would be a medical emergency.
• Rare Diagnoses
  • Porphyria cutanea tarda: A rare genetic disorder that can cause blistering skin lesions, particularly in areas exposed to sunlight, and is associated with liver disease.
  • Cutaneous metastasis: Although rare, it's possible for hepatocellular carcinoma to metastasize to the skin, presenting as skin lesions.
  • Erythema gyratum repens: A rare skin condition associated with underlying malignancies, characterized by wavy, erythematous lesions.

Each of these diagnoses should be considered in the context of the patient's overall clinical presentation, and a thorough diagnostic workup should be conducted to determine the underlying cause of the cutaneous manifestations.