Specific code 2011 ICD-9-CM Diagnosis Code 491.20
Obstructive chronic bronchitis without exacerbation
  • Short description: Obst chr bronc w/o exac.
  • ICD-9-CM 491.20 will be replaced by an equivalent ICD-10-CM code (or codes) when the United States transitions from ICD-9-CM to ICD-10-CM on October 1, 2015.
  • ICD-9-CM 491.20 is a billable medical code that can be used to specify a diagnosis on a reimbursement claim.
  • You are viewing the 2011 version of ICD-9-CM 491.20.
  • More recent version(s) of ICD-9-CM 491.20: 2012 2013 2014.
Disease Synonyms
  • Chronic bronchitis, obstructive
  • Chronic obstructive bronchitis
  • Emphysematous bronchitis
Applies To
  • Emphysema with chronic bronchitis
Convert to ICD-10-CM: 491.20 converts approximately to:
  • 2014 ICD-10-CM J44.9 Chronic obstructive pulmonary disease, unspecified
ICD-9-CM Volume 2 Index entries containing back-references to 491.20:
  • Blue
    • bloater 491.20
  • Bronchitis (diffuse) (hypostatic) (infectious) (inflammatory) (simple) 490
    • with
      • emphysema - see Emphysema
      • influenza, flue, or grippe (see also Influenza) 487.1
      • obstruction airway, chronic 491.20
      • tracheitis 490
    • emphysematous 491.20
    • obstructive (chronic) 491.20
  • Disease, diseased - see also Syndrome
    • pulmonary - see also Disease, lung
      • amyloid 277.39 [517.8]
      • artery 417.9
      • circulation, circulatory 417.9
      • diffuse obstructive (chronic) 496
        • with
          • acute bronchitis 491.22
          • asthma (chronic) (obstructive) 493.2
          • exacerbation NEC (acute) 491.21
      • heart (chronic) 416.9
      • hypertensive (vascular) 416.0
      • obstructive diffuse (chronic) 496
        • with
          • acute bronchitis 491.22
          • asthma (chronic) (obstructive) 493.2
          • bronchitis (chronic) 491.20
          • exacerbation NEC (acute) 491.21
        • decompensated 491.21
      • valve (see also Endocarditis, pulmonary) 424.3
  • Emphysema (atrophic) (centriacinar) (centrilobular) (chronic) (diffuse) (essential) (hypertrophic) (interlobular) (lung) (obstructive) (panlobular) (paracicatricial) (paracinar) (postural) (pulmonary) (senile) (subpleural) (traction) (unilateral) (unilobular) (vesicular) 492.8
    • with bronchitis
      • chronic 491.20
  • Obstruction, obstructed, obstructive
    • airway NEC 519.8
      • with
        • allergic alveolitis NEC 495.9
        • asthma NEC (see also Asthma) 493.9
        • bronchiectasis 494.0
          • with acute exacerbation 494.1
        • bronchitis (see also Bronchitis, with, obstruction) 491.20
        • emphysema NEC 492.8
      • chronic 496
        • with
          • allergic alveolitis NEC 495.5
          • asthma NEC (see also Asthma) 493.2
          • bronchiectasis 494.0
            • with acute exacerbation 494.1
          • bronchitis (chronic) (see also Bronchitis, chronic, obstructive) 491.20
          • emphysema NEC 492.8
      • due to
    • lung 518.89
      • with
        • asthma - see Asthma
        • bronchitis (chronic) 491.20
        • emphysema NEC 492.8
      • airway, chronic 496
      • chronic NEC 496
        • with
          • asthma (chronic) (obstructive) 493.2
      • disease, chronic 496
        • with
          • asthma (chronic) (obstructive) 493.2
      • emphysematous 492.8
  • Syndrome - see also Disease
ICD-9-CM codes are used in medical billing and coding to describe diseases, injuries, symptoms and conditions. ICD-9-CM 491.20 is one of thousands of ICD-9-CM codes used in healthcare. Although ICD-9-CM and CPT codes are largely numeric, they differ in that CPT codes describe medical procedures and services. Can't find a code? Start at the root of ICD-9-CM, check the 2011 ICD-9-CM Index or use the search engine at the top of this page to lookup any code.