ICD-10 Code for Mycobacterium
Also indexed as (infection)
The ICD-10-CM code for mycobacterium is A31.9 — Mycobacterial infection, unspecified. This is the code the Alphabetic Index gives for mycobacterium with no further qualifier, valid for FY2027 (October 1, 2026 – September 30, 2027).
A31.9 is billable but unspecified. If the documentation names a type, site or cause, one of the more specific codes below is likely expected.
Which mycobacterium code should you use?
The Alphabetic Index lists 5 codes under Mycobacterium, mycobacterial. Which one applies depends on the qualifier documented in the record — the type, site, cause, or associated condition. Find the qualifier below, then verify the code in the Tabular List before using it.
By type
| anonymous | A31.9 | Mycobacterial infection, unspecified | |
| atypical | A31.9 | Mycobacterial infection, unspecified | |
| avium | A31.0 | Pulmonary mycobacterial infection | |
| balnei | A31.1 | Cutaneous mycobacterial infection | |
| Battey | A31.0 | Pulmonary mycobacterial infection | |
| chelonei | A31.8 | Other mycobacterial infections | |
| cutaneous | A31.1 | Cutaneous mycobacterial infection | |
| extrapulmonary systemic | A31.8 | Other mycobacterial infections | |
| fortuitum | A31.8 | Other mycobacterial infections | |
| intracellulare | A31.0 | Pulmonary mycobacterial infection | |
| kansasii | A31.0 | Pulmonary mycobacterial infection | |
| kakaferifu | A31.8 | Other mycobacterial infections | |
| kasongo | A31.8 | Other mycobacterial infections | |
| leprae | A30.9 | Leprosy, unspecified | |
| luciflavum | A31.1 | Cutaneous mycobacterial infection | |
| marinum | A31.1 | Cutaneous mycobacterial infection | |
| pulmonary | A31.0 | Pulmonary mycobacterial infection | |
| scrofulaceum | A31.8 | Other mycobacterial infections | |
| simiae | A31.8 | Other mycobacterial infections | |
| systemic, extrapulmonary | A31.8 | Other mycobacterial infections | |
| szulgai | A31.8 | Other mycobacterial infections | |
| terrae | A31.8 | Other mycobacterial infections | |
| triviale | A31.8 | Other mycobacterial infections | |
| ulcerans | A31.1 | Cutaneous mycobacterial infection | |
| xenopi | A31.8 | Other mycobacterial infections |
Index terms and codes are reproduced from the official ICD-10-CM FY2027 release. The Alphabetic Index is a finding aid — a code must always be verified in the Tabular List before it is reported. Data sources