Paraneoplastic pemphigus

This code represents a rare, severe autoimmune blistering disease characterized by painful erosions of the skin and mucous membranes, often associated with an underlying neoplasm. It is distinguished by the presence of specific autoantibodies targeting plakin proteins.

Apply this code when documentation clearly indicates a diagnosis of paraneoplastic pemphigus, typically confirmed by clinical presentation, histopathology, and immunofluorescence studies showing characteristic autoantibody patterns. This diagnosis is often made in patients with known or suspected underlying malignancies.

• Ensure the medical record explicitly states "paraneoplastic pemphigus" to support this specific code.
• Do not confuse with other forms of pemphigus (e.g., pemphigus vulgaris, pemphigus foliaceus) which have distinct codes.
• Always code the underlying neoplasm first, followed by this code, as paraneoplastic pemphigus is a manifestation of the malignancy.