Is M1A a billable ICD-10-CM code?

No. M1A is a non-billable header code. Code to a higher level of specificity using one of its child codes.

Where does M1A sit in the tabular list?

Diseases of the musculoskeletal system and connective tissue (M00-M99), in the block Inflammatory polyarthropathies (M05-M14).

What cannot be coded together with M1A?

M1A carries an Excludes1 note, which means the conditions it lists can never be coded together with it on the same encounter.

M1A

M1A — Chronic gout

Non-billable headerICD-10-CM

M1A is a non-billable header ICD-10-CM code for chronic gout. It cannot be billed on its own: choose one of the more specific child codes below. This code also requires a 7th character before it is complete.

This code requires a 7th character

The appropriate 7th character is to be added to each code from category M1A

0: without tophus (tophi)
1: with tophus (tophi)

Excludes1 — never code together

These conditions cannot occur together. Billing both on the same encounter is a denial.

gout NOS (M10.-)

Excludes2 — not included here, but may coexist

The excluded condition is not part of this code, but a patient can have both. You may code both.

acute gout (M10.-)

Use additional code

Add a secondary code to capture the detail described below.

code to identify:
Autonomic neuropathy in diseases classified elsewhere (G99.0)
Calculus of urinary tract in diseases classified elsewhere (N22)
Cardiomyopathy in diseases classified elsewhere (I43)
Disorders of external ear in diseases classified elsewhere (H61.1-, H62.8-)
Disorders of iris and ciliary body in diseases classified elsewhere (H22)
Glomerular disorders in diseases classified elsewhere (N08)

Other codes that can never be billed with M1A

These codes carry an Excludes1 note pointing at M1A. The conflict binds both ways, but ICD-10-CM only writes it down on one side — so you would not find this by reading M1A alone.

E79Disorders of purine and pyrimidine metabolism
E72Other disorders of amino-acid metabolism

Risk adjustment

M1A does not map to an HCC and does not risk-adjust under CMS-HCC V28. That is normal — most ICD-10 codes do not. It still needs to be coded correctly; it just will not move a RAF score.

Code to one of these instead M1A

6 child codes. Green means billable.

Questions about M1A

Is M1A a billable ICD-10-CM code?: No. M1A is a non-billable header code. Code to a higher level of specificity using one of its child codes.
Where does M1A sit in the tabular list?: Diseases of the musculoskeletal system and connective tissue (M00-M99), in the block Inflammatory polyarthropathies (M05-M14).
What cannot be coded together with M1A?: M1A carries an Excludes1 note, which means the conditions it lists can never be coded together with it on the same encounter.