ED Coding and Reimbursement Alert

Question: We saw a patient with gout and we aren’t sure how to report this condition, because the ICD-10 code book contains dozens of codes for this condition. Can you advise?

Ohio Subscriber

Answer: Gout is a condition that occurs due to monosodium urate crystal deposition, and patients may report to the ED with this diagnosis if the symptoms become painful or get in the way of movement. However, you’ll need more details before you can select an appropriate diagnosis for this condition.

If you don’t have details, you can report M10.9 (Gout, unspecified), but in most cases, insurers will want more information beyond that. For chronic gout, you’ll use the M1A- (Chronic gout) group. For acute grout, you should look to the M10- (Gout) group.

Avoid 7th character confusion: Aside from documenting the different manifestations of the condition, the other major difference between the M1A- and M10- code groups is that only category M1A- takes an additional 7th character, either 0 or 1, to mark the absence or presence of tophi, respectively.

Coding example: To document drug-induced chronic gout in the patient’s left ankle and foot with tophi, you would report M1A.2721 (Drug-induced chronic gout, left ankle and foot, with tophus (tophi)).

On the other hand, to report drug-induced chronic gout of the left ankle and foot without tophi, you would report M1A.2720 (Drug-induced chronic gout, left ankle and foot, without tophus (tophi)). In addition, keep in mind that both the M1A.- and M10.- code sets make a distinction between primary or secondary gout, which is gout caused by a medication or another medical condition. The codes are then broken down by etiology using the following 4th characters:

• MXX.0 — Idiopathic gout (meaning that the gout has occurred spontaneously, and the cause is unknown)
• MXX.1 — Lead-induced gout
• MXX.2 — Drug-induced gout
• MXX.3 — Gout due to renal impairment
• MXX.4 — Other secondary gout
• MXX.9 — Unspecified

When your provider assigns a secondary gout code group, such as renal failure with MXX.3, make sure you obey the code first notes associated with the code groups. In the case of renal failure, for example, that note reads “code first associated renal disease.” For other secondary gout causes besides lead, drugs, and renal impairment, you will go to MXX.4 and follow the instructions to code the associated condition first.

Coding example: For a patient that has chronic gout without tophi in the right ankle and foot due to arthropathic psoriasis, you would code L40.5- (Arthropathic psoriasis) first, followed by M1A.4710 (Other secondary chronic gout, right ankle and foot, without tophus (tophi)).

The 5th character in a gout code pinpoints the exact anatomic location. For the ankle and foot, you will see “7” as this 5th character.

For example, to report idiopathic chronic gout of the right ankle and foot, without tophus, you would report M1A.0710 (Idiopathic chronic gout, right ankle and foot, without tophus (tophi)). To report lead-induced gout of the left ankle and foot, you would report M10.172 (Lead-induced gout, left ankle and foot).

The 6th character identifies the side of the body where the disease has been found. Therefore, expansion 1 is for the right side, 2 for the left, and 9 for the unspecified side of the body.

Coding example: If M10.17- is for lead-induced gout of ankle and foot, then you can expect to find M10.171 (… right ankle and foot), M10.172 (… left ankle and foot), and M10.179 (Lead-induced gout, unspecified ankle and foot) as the final subcategories.