B49 — Unspecified mycosis
Is B49 billable?
Yes, but B49 is an unspecified code. B49 is a valid, billable ICD-10-CM code for encounters from October 1, 2026 through September 30, 2027. However, B49 is an unspecified or catch-all code. Payers apply additional scrutiny to unspecified codes and many deny them when the medical record supports a more specific option, so check the documentation before selecting B49.
B49 at a glance
| Code | B49 |
|---|---|
| Description | Unspecified mycosis |
| Billable | Yes |
| Code set | ICD-10-CM FY2027 |
| Valid for encounters | October 1, 2026 – September 30, 2027 |
Which MS-DRGs does B49 group to?
B49 sits in MDC 18 and helps define the logic of 3 MS-DRGs (version 44, FY2027). Which one a stay actually groups to also depends on procedures and secondary diagnoses.
- 867Other Infectious and Parasitic Diseases Diagnoses with MCCmedical
- 868Other Infectious and Parasitic Diseases Diagnoses with CCmedical
- 869Other Infectious and Parasitic Diseases Diagnoses without CC/MCCmedical
As a secondary diagnosis, B49 is a complication or comorbidity (CC), which can move a stay into a higher-paying DRG.
How is B49 listed in the Alphabetic Index?
These are the routes through the Alphabetic Index that lead to B49. They show the wording a clinician may have documented, which often differs from the Tabular description.
- Bronchomycosis NOS
- Fungemia NOS
- Keratomycosis
- Mycelium infection
- Mycosis, mycotic
- Pneumomycosis
- Arthritis, arthritic › mycotic NEC (acute) (chronic) (nonpyogenic) (subacute)
- Cough › tea taster's (affected) (epidemic) (nervous)
- Diarrhea, diarrheal › mycotic NEC (disease) (infantile) (inflammatory)
- Disease, diseased › fungus NEC
- Disease, diseased › mycotic
- Fungus, fungous › disease NOS
Inclusion terms
Alternative wording in documentation that is classified to B49.
- Fungemia NOS
Use additional code — inherited from Chapter 1
Report an additional code alongside B49 to fully describe the condition. B49 is sequenced first.
- code to identify resistance to antimicrobial drugs (Z16.-)
Excludes2 — not included here — inherited from Chapter 1
The conditions below are not part of B49, but a patient may have both at the same time. When documentation supports it, B49 and the excluded code may both be reported.
- carrier or suspected carrier of infectious disease (Z22.-)
- certain localized infections - see body system-related chapters
- infectious and parasitic diseases complicating pregnancy, childbirth and the puerperium (O98.-)
- infectious and parasitic diseases specific to the perinatal period (P35-P39)
- influenza and other acute respiratory infections (J00-J22)
Excludes2 — not included here — inherited from B35-B49
The conditions below are not part of B49, but a patient may have both at the same time. When documentation supports it, B49 and the excluded code may both be reported.
How long has B49 existed?
B49 has been in ICD-10-CM since at least FY2016, the earliest fiscal year on record here.
Derived from the official order files for FY2016–FY2026. FY2017 and FY2020 publish no order file, so those years are not covered.