Meningococcal infection (A39) ICD-10-CM
The A39 code range covers meningococcal infection with 18 ICD-10-CM diagnosis codes. 15 of them are billable and valid for claim submission in fiscal year 2026, and the category headers group them but cannot themselves be billed.
Codes in the A39 Range 18 codes · 15 billable
- A39 Meningococcal infectionNon-billable
- A39.0 Meningococcal meningitis
- A39.1 Waterhouse-Friderichsen syndrome
- A39.2 Acute meningococcemia
- A39.3 Chronic meningococcemia
- A39.4 Meningococcemia, unspecified
- A39.5 Meningococcal heart diseaseNon-billable
- A39.50 Meningococcal carditis, unspecified
- A39.51 Meningococcal endocarditis
- A39.52 Meningococcal myocarditis
- A39.53 Meningococcal pericarditis
- A39.8 Other meningococcal infectionsNon-billable
- A39.81 Meningococcal encephalitis
- A39.82 Meningococcal retrobulbar neuritis
- A39.83 Meningococcal arthritis
- A39.84 Postmeningococcal arthritis
- A39.89 Other meningococcal infections
- A39.9 Meningococcal infection, unspecified
Clinical Terms in This Code Range
Definitions from the National Library of Medicine for conditions coded in the A39 range.
Meningococcal Infections
Infections with bacteria of the species NEISSERIA MENINGITIDIS.
Neisseria meningitidis
A species of gram-negative, aerobic BACTERIA. It is a commensal and pathogen only of humans, and can be carried asymptomatically in the NASOPHARYNX. When found in cerebrospinal fluid it is the causative agent of cerebrospinal meningitis (MENINGITIS, MENINGOCOCCAL). It is also found in venereal discharges and blood. There are at least 13 serogroups based on antigenic differences in the capsular polysaccharides; the ones causing most meningitis infections being A, B, C, Y, and W-135. Each serogroup can be further classified by serotype, serosubtype, and immunotype.
About the A39 Code Range
The ICD-10 code section A39 covers all meningococcal infections, which are caused by the bacteria Neisseria meningitidis and can affect various body systems. These codes are used to classify specific meningococcal conditions, from meningitis to bloodstream infections and complications like heart or joint involvement.
This section includes codes such as A39.0 for meningococcal meningitis, also known as meningitis caused by gram-negative aerobic cocci. It spans serious infections like Waterhouse-Friderichsen syndrome (A39.1), a severe adrenal hemorrhage condition, and acute or chronic meningococcemia (A39.2, A39.3), which describe meningococcal bloodstream infections. Cardiac complications caused by meningococcal bacteria, including endocarditis, myocarditis, or pericarditis, are coded under A39.5 with specific subcodes A39.50–A39.53. Other less common infections like meningococcal encephalitis (A39.81), retrobulbar neuritis, or arthritis are also covered. The unspecified or general invasive meningococcal disease falls under A39.9, commonly referred to as sepsis caused by meningococcus. These detailed ICD-10 codes help accurately document the specific type and manifestation of meningococcal infection for clinical and billing purposes.
Questions About This Page
How many billable codes are in the A39 range?
Of the 18 codes in this range, 15 are billable and valid for claim submission from October 1, 2025 through September 30, 2026. Category header codes group them but cannot be reported on claims.
What does the A39 range classify?
The range classifies meningococcal infection. Each code links to its own reference page with billing status, MS-DRG grouping, coding notes, and clinical information.
Related References
Source: CMS FY 2026 ICD-10-CM Tabular List and order file, effective October 1, 2025 through September 30, 2026.
