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2015 ICD-9-CM Diagnosis Code 491.21
Obstructive chronic bronchitis with (acute) exacerbation
- 2015
- Billable Thru Sept 30/2015
- Non-Billable On/After Oct 1/2015
- ICD-9-CM 491.21 is a billable medical code that can be used to indicate a diagnosis on a reimbursement claim, however, 491.21 should only be used for claims with a date of service on or before September 30, 2015. For claims with a date of service on or after October 1, 2015, use an equivalent ICD-10-CM code (or codes).
Convert to ICD-10-CM:
491.21 converts approximately to:
- 2015/16 ICD-10-CM J44.1 Chronic obstructive pulmonary disease with (acute) exacerbation
Approximate Synonyms
- Acute exacerbation of chronic obstructive airways disease
- Acute exacerbation of chronic obstructive bronchitis
- Acute exacerbation of COPD
- Chronic obstructive bronchitis with exacerbation
- Chronic obstructive pulmonary disease, acute flare-up
- COPD W acute exacerbation
491.21 Excludes
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- chronic obstructive asthma with acute exacerbation 493.22
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Applies To
- Acute exacerbation of chronic obstructive pulmonary disease [COPD]
- Decompensated chronic obstructive pulmonary disease [COPD]
- Decompensated chronic obstructive pulmonary disease [COPD] with exacerbation
ICD-9-CM Volume 2 Index entries containing back-references to
491.21:
- Blue
bloater 491.20![](/images/note.png)
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with![](/images/16x16.gif)
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acute bronchitis 491.22![](/images/note.png)
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exacerbation (acute) 491.21
- Bronchitis (diffuse) (hypostatic) (infectious) (inflammatory) (simple) 490
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with![](/images/vertical.gif)
emphysema - see Emphysema![](/images/vertical.gif)
influenza, flue, or grippe (see also Influenza) 487.1![](/images/note.png)
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obstruction airway, chronic 491.20![](/images/note.png)
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with![](/images/vertical.gif)
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acute bronchitis 491.22![](/images/note.png)
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exacerbation (acute) 491.21
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tracheitis 490![](/images/note.png)
emphysematous 491.20![](/images/note.png)
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with![](/images/vertical.gif)
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acute bronchitis 491.22![](/images/note.png)
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exacerbation (acute) 491.21
obstructive (chronic) 491.20![](/images/note.png)
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with![](/images/16x16.gif)
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acute bronchitis 491.22![](/images/note.png)
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exacerbation (acute) 491.21
- Disease, diseased - see also Syndrome
lung NEC 518.89![](/images/note.png)
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black 500![](/images/note.png)
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congenital 748.60![](/images/note.png)
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cystic 518.89![](/images/note.png)
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fibroid (chronic) (see also Fibrosis, lung) 515![](/images/note.png)
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fluke 121.2![](/images/note.png)
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in![](/images/vertical.gif)
interstitial (chronic) 515![](/images/note.png)
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nonspecific, chronic 496![](/images/note.png)
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obstructive (chronic) (COPD) 496![](/images/note.png)
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with![](/images/vertical.gif)
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acute![](/images/vertical.gif)
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bronchitis 491.22![](/images/note.png)
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exacerbation NEC 491.21
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alveolitis, allergic (see also Alveolitis, allergic) 495.9![](/images/note.png)
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asthma (chronic) (obstructive) 493.2![](/images/note.png)
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bronchiectasis 494.0![](/images/note.png)
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with acute exacerbation 494.1![](/images/note.png)
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bronchitis (chronic) 491.20![](/images/note.png)
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with![](/images/vertical.gif)
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acute bronchitis 491.22![](/images/note.png)
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exacerbation (acute) 491.21
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decompensated 491.21![](/images/vertical.gif)
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with exacerbation 491.21![](/images/vertical.gif)
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with![](/images/vertical.gif)
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exacerbation (acute) 491.21
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emphysema NEC 492.8![](/images/note.png)
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diffuse (with fibrosis) 496![](/images/note.png)
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of childhood, specified NEC 516.69![](/images/note.png)
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polycystic 518.89![](/images/note.png)
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asthma (chronic) (obstructive) 493.2![](/images/note.png)
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congenital 748.4![](/images/note.png)
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purulent (cavitary) 513.0![](/images/note.png)
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restrictive 518.89![](/images/note.png)
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rheumatoid 714.81![](/images/note.png)
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specified NEC 518.89![](/images/note.png)
pulmonary - see also Disease, lung![](/images/16x16.gif)
amyloid 277.39
[517.8
]![](/images/16x16.gif)
artery 417.9![](/images/note.png)
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circulation, circulatory 417.9![](/images/note.png)
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diffuse obstructive (chronic) 496![](/images/note.png)
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with![](/images/16x16.gif)
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acute bronchitis 491.22![](/images/note.png)
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asthma (chronic) (obstructive) 493.2![](/images/note.png)
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exacerbation NEC (acute) 491.21
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heart (chronic) 416.9![](/images/note.png)
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hypertensive (vascular) 416.0![](/images/note.png)
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obstructive diffuse (chronic) 496![](/images/note.png)
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with![](/images/16x16.gif)
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acute bronchitis 491.22![](/images/note.png)
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asthma (chronic) (obstructive) 493.2![](/images/note.png)
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bronchitis (chronic) 491.20![](/images/note.png)
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exacerbation NEC (acute) 491.21
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decompensated 491.21
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valve (see also Endocarditis, pulmonary) 424.3![](/images/note.png)
- Embryoma (M9080/1) - see also Neoplasm, by site, uncertain behavior
malignant (M9080/3) - see also Neoplasm, by site, malignant![](/images/16x16.gif)
kidney (M8960/3) 189.0![](/images/note.png)
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liver (M8970/3) 155.0![](/images/note.png)
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testis (M9070/3) 186.9![](/images/note.png)
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undescended 186.0![](/images/note.png)
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with![](/images/16x16.gif)
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acute bronchitis 491.22![](/images/note.png)
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exacerbation (acute) 491.21
- Syndrome - see also Disease
autosomal - see also Abnormal, autosomes NEC