Drug-induced chronic gout, unsp ankle and foot, with tophus

This code signifies chronic gout caused by medication, affecting an unspecified ankle or foot, and characterized by the presence of tophi. Tophi are deposits of uric acid crystals that form visible lumps under the skin, often in chronic cases of gout. The drug-induced nature indicates that a specific medication is the causative agent of the gout.

Use this code when documentation clearly states chronic gout in the ankle or foot, explicitly links it to a drug, and confirms the presence of tophi. This applies to patients experiencing long-term, recurrent gout attacks in these specific anatomical sites, where a medication is identified as the trigger.

• Ensure documentation specifies "chronic" gout and explicitly states "drug-induced" as the etiology.
• Verify the presence of tophi in the medical record; without tophi, a different code for drug-induced chronic gout would be appropriate.
• Always code the adverse effect of the drug (T36-T50 with a 5th or 6th character of 5) as a secondary diagnosis to fully capture the clinical picture.