All ICD10 Codes

B99

Non-Billable
ChapterA00–B99
Rankcategory
Official Description

Other and unspecified infectious diseases

Metadata & Insights
  • •2026 ICD-10-CM Edition - Effective October 1, 2025.
  • •Non-billable category (requires more specific sub-code).
  • •Chapter 1: Certain Infectious and Parasitic Diseases (A00-B99).

CH1 Parent Instructions

Includes
  • diseases generally recognized as communicable or transmissible
Excludes1(Not coded here)
  • certain localized infections - see body system-related chapters
Excludes2(Not included here)
  • carrier or suspected carrier of infectious disease (Z22.-)
  • 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)
Use Additional Code
  • code to identify resistance to antimicrobial drugs (Z16.-)

Clinical Hierarchy

CH1Certain infectious and parasitic diseases (A00-B99)
B99Other and unspecified infectious diseases
B99.8Other infectious disease
B99.9Unspecified infectious disease

Applicable Ancestor Context

The following parent sections contain instructions or notes that apply to B99:

chapterCH1
Certain infectious and parasitic diseases (A00-B99)
View context instructions

Alphabetic Index Mentions

These are Diagnosis Index lookup paths that route to B99. Use them as entry terms for search, then confirm final coding instructions in the Tabular List and notes above.

21 raw paths
Arthropathy1 unique routes
postinfectious NEC→B99
Conjunctivitis (staphylococcal) (streptococcal) NOS1 unique routes
in (due to)
infectious disease NEC→B99
Disease, diseased4 unique routes
epidemic→B99(2 variants)
specified NEC→B99
infectious, infective→B99(2 variants)
specified NEC→B99
Encephalitis (chronic) (hemorrhagic) (idiopathic) (nonepidemic) (spurious) (subacute)1 unique routes
in (due to)
infectious disease NEC→B99
Fever (inanition) (of unknown origin) (persistent) (with chills) (with rigor)2 unique routes
infective→B99(2 variants)
specified NEC→B99
Granuloma2 unique routes
infectious→B99(2 variants)
specified NEC→B99
Infection, infected, infective (opportunistic)2 unique routes
Direct index entry→B99
specified NEC→B99
Iridocyclitis1 unique routes
in (due to)
infectious disease NOS→B99
Mastoiditis (coalescent) (hemorrhagic) (suppurative)1 unique routes
in (due to)
infectious disease NEC→B99
Myopathy1 unique routes
in (due to)
infectious disease NEC→B99
Neuritis (rheumatoid)1 unique routes
acoustic (nerve)
in (due to)
infectious disease NEC→B99
Otitis (acute)1 unique routes
externa
in (due to)
infectious disease NEC→B99
Palsy1 unique routes
cranial nerve
multiple
in
infectious disease→B99
Pneumonia (acute) (double) (migratory) (purulent) (septic) (unresolved)1 unique routes
postinfectional NEC→B99
Polyneuropathy (peripheral)1 unique routes
in (due to)
infectious
disease NEC→B99

MS-DRG Classification

2026

No direct MS-DRG triggers identified.

Cross Reference

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