Bullous disorders in diseases classified elsewhere

This code represents bullous skin conditions that are a manifestation or complication of another underlying disease process, rather than a primary skin disorder. These are blistering diseases where the primary etiology lies outside the integumentary system.

Use this code when documentation clearly links a bullous eruption to a systemic disease, such as bullous pemphigoid in lupus erythematosus or drug-induced bullous reactions. The medical record must specify the underlying condition causing the bullae.

• Always sequence the underlying systemic disease first, followed by this code.
• Do not use for primary bullous disorders like pemphigus vulgaris or bullous pemphigoid of unknown etiology; these have their own specific codes.
• Ensure the physician's documentation explicitly states the causal relationship between the systemic disease and the bullous manifestation.