Idiopathic gout, unspecified knee

This code signifies a form of arthritis caused by the accumulation of uric acid crystals in the joint, specifically affecting an unspecified knee, where the underlying cause of the elevated uric acid is unknown. It represents a primary gout condition without a secondary identifiable etiology.

Use this code when documentation clearly states a diagnosis of idiopathic gout affecting the knee, but the specific laterality (right or left) is not documented. This is appropriate for initial or subsequent encounters where the physician has diagnosed gout of unknown origin in the knee joint.

• Avoid using this code if the laterality of the affected knee is specified; instead, use M10.061 for right knee or M10.062 for left knee.
• Do not use this code if the gout is secondary to another condition (e.g., drug-induced, lead poisoning); refer to codes in the M10.2-M10.4 series.
• Ensure documentation supports the "idiopathic" nature of the gout; if a cause is known, a more specific code is required.