491.9 CHRONIC BRONCHITIS NOS


Code Information

Diagnosis Code: 491.9

Short Description: Chronic bronchitis NOS

Long Description: Unspecified chronic bronchitis

Code Classification:

  • Diseases of the respiratory system (460–519)
    • Chronic obstructive pulmonary disease and allied conditions (490-496)
      • 491 Chronic bronchitis
        • 491.9 Chronic bronchitis NOS

Code Version: 2015 ICD-9-CM


References to Index of Diseases and Injuries

The code 491.9 has the following ICD-9-CM references to the Index of Diseases and Injuries
  • Bronchitis (diffuse) (hypostatic) (infectious) (inflammatory) (simple) 490
    • chronic 491.9
      • with
        • tracheitis (chronic) 491.8
      • asthmatic 493.2
      • catarrhal 491.0
      • chemical (due to fumes and vapors) 506.4
      • due to
        • fumes or vapors (chemical) (inhalation) 506.4
        • radiation 508.8
        • tobacco smoking 491.0
      • mucopurulent 491.1
      • obstructive 491.20
        • with
          • acute bronchitis 491.22
          • exacerbation (acute) 491.21
      • purulent 491.1
      • simple 491.0
      • specified type NEC 491.8
    • senile 491.9
  • Peribronchitis 491.9
    • tuberculous (see also Tuberculosis) 011.3
  • Perichondritis
    • bronchus 491.9

Crosswalk Information

The code 491.9 converts into the following ICD-10 code(s):
ICD-9 Code ICD-10 Code ICD-10 Description
491.9 Right Arrow J42 Unspecified chronic bronchitis
This ICD-9 to ICD-10 data is based on the 2018 General Equivalency Mapping (GEM) files published by the Centers for Medicare & Medicaid Services (CMS) for informational purposes only. The data is not an ICD-10 conversion tool and doesn’t guarantee clinical accuracy.

Similar Codes

ICD-9 Code ICD-9 Description
491.0 Simple chronic bronchitis
491.1 Mucopurulent chronic bronchitis
491.20 Obstructive chronic bronchitis without exacerbation
491.21 Obstructive chronic bronchitis with (acute) exacerbation
491.22 Obstructive chronic bronchitis with acute bronchitis
491.8 Other chronic bronchitis


This page was last updated on: 10/1/2014