Gout ICD-10-CM codes

Gout has two categories. M10 is used for acute attacks and for gout that is not documented as chronic; M1A is chronic gout and adds a 7th character for tophi: 0 without tophus and 1 with tophus. M10.9 (gout, unspecified) is the most common code when neither cause nor site is documented. When the record supports it, use the cause at the 4th character (0 idiopathic, 1 lead-induced, 2 drug-induced, 3 due to renal impairment, 4 other secondary) and the joint at the 5th and 6th characters, for example M10.071 for an idiopathic gout flare in the right ankle or foot (the podagra pattern).

M1A is a separate category rather than a 5th character of M10, so chronic tophaceous gout of an unspecified site is M1A.9XX1 and the site-specific codes follow the same joint scheme with a placeholder X where needed. M1A and M10 are mutually exclusive by Excludes1 notes; an acute flare in a patient with chronic gout is reported with the M1A code only, since M1A covers the disease and its flares. Drug-induced gout (M10.2-, M1A.2-) takes an additional T36-T50 adverse effect code for the drug, and gout due to renal impairment (M10.3-, M1A.3-) carries a code-first note for the associated renal disease.

Asymptomatic hyperuricemia found on labs without arthritis or tophi is E79.0, a chapter 4 metabolic code, and should not be coded as gout. Pseudogout (calcium pyrophosphate deposition) is M11.2- and is not a gout code. Long-term urate-lowering therapy is Z79.899.