Orthopedic Coding Alert

Colorado Subscriber

Answer: You’ll need quite a bit more information about the condition before selecting the most accurate diagnosis code. If “chronic gout” is all you have to code from, then you’ll select M1A.9 (Chronic gout, unspecified).

That option, however, is a last resort. Go back and check the notes; then, follow these instructions to get a more specific chronic gout code.

All of your coding options will start with this base: M1A.- (Chronic gout). From there, you’ll need to go to the 7th character for most of the diagnoses. Here’s a look at the detail contained in the 4th through 7th characters:

• 4th character: This character indicates the type of chronic gout the patient suffers from: idiopathic, lead-induced, drug-induced, chronic gout due to renal impairment, or other secondary chronic gout.
• 5th character: This character indicates what part of the body the gout is affecting: shoulder, elbow, wrist, hand, hip, knee, ankle and foot, vertebrae, or multiple sites.
• 6th character: This character indicates the laterality of the chronic gout: right, left, or unspecified.
• 7th character: This character indicates whether the patient has tophus in addition to chronic gout. Tophus occurs when a deposit of monosodium urate crystals forms around the affected area. They can erode through the skin, often leading to a chalky white appearance. Tophi can be very small — almost unidentifiable — or they can be huge lumps.

So let’s say a patient is suffering from idiopathic chronic gout in their right hand with tophi. The correct ICD-10 code would be M1A.0411 (Idiopathic chronic gout, right hand, with tophus (tophi)).