Calculus of urinary tract in diseases classified elsewhere

This code signifies the presence of urinary tract calculi (stones) that are a manifestation or complication of another underlying disease process. It indicates that the calculus itself is not the primary condition, but rather a secondary finding directly attributable to a separate, specified illness.

Use this code when documentation clearly links urinary tract calculi to an underlying systemic disease, such as Crohn's disease, hyperparathyroidism, or certain metabolic disorders. The medical record must explicitly state the causal relationship between the primary disease and the formation of the stones.

• Always sequence the underlying disease first, followed by this code.
• Do not use this code if the calculus is idiopathic or due to a cause not classified elsewhere; use codes from N20-N21 instead.
• Ensure the documentation specifies the type and location of the calculus (e.g., kidney, ureter) if known, as more specific codes may be available for the calculus itself.