Respiratory disorders in diseases classified elsewhere

This code represents respiratory manifestations that occur as a complication or associated feature of another underlying disease process, where the respiratory involvement is not the primary diagnosis. It signifies pulmonary conditions that are secondary to a systemic illness classified elsewhere in the ICD-10-CM system.

Use this code when the medical record clearly links a respiratory disorder (e.g., pneumonia, bronchitis, interstitial lung disease) to an underlying systemic disease not specifically listed in the Excludes1 note. Documentation should explicitly state the causal relationship, such as "pneumonia due to rheumatoid arthritis" or "pulmonary involvement secondary to Crohn's disease."

• Always sequence the underlying systemic disease first, followed by this code for the respiratory manifestation.
• Carefully review the "Excludes1" list; if the underlying disease is on this list, a more specific code linking the two conditions will exist and should be used instead.
• Ensure the documentation clearly establishes a "due to" or "secondary to" relationship between the systemic disease and the respiratory disorder.