Diagnosis
Increase in color and production of sputum with increased dyspnea.
Epidemiologic Risks
COPD.
Microbiology
There is microbiome of the lung and in COPD may in part be due to alternation in the microbiome. There is an increase in Firmicutes and Enterobacteriaceae and a decrease in Bacteroidetes (Pubmed).
H. influenza, S. pneumoniae, and M. catarrhalis predominate, but it may a generalized increase in bacteria and not any one specific organism. However, the acquisition of new bacterial strains is associated with exacerbations. Pseudomonas is increasingly identified as a cause of progression of COPD (PubMed) and doubles the mortality (PubMed).Pneumocystis (Pubmed) may have a role in the pathogenesis combined with a change in the microbiome, especially in HIV patients.
Aspergillus may be playing a role: "Serum Aspergillus galactomannan antigen was detected in patients with COPD, and elevated serum Aspergillus galactomannan antigen was associated with severe AE COPD (PubMed)."
Empiric Therapy
The worser the exacerbation, the better the response to antibiotics. Anything will do and there is no data to suggest that newer, broad-spectrum or more expensive antibiotics will lead to a better outcome. Worry about H. influenza, S. pneumoniae, and M. catarrhalis, but probably not their resistance to antibiotics, no matter what the drug rep says.
Overall, antibiotics decrease treatment failure with mild to moderate exacerbations. Antibiotics decrease mortality and treatment failure for patients with severe exacerbation who are admitted to an ICU. But. For mild to moderate disease and a low procalcitonin, antibiotics beyond 24 hours they do nothing (PubMed)
Try amoxicillin OR tmp/sulfa OR doxycycline orally, probably any po or iv antibiotics for 5 to 10 days, depending on how ill they are.
Patients who receive early antibiotics are less likely to receive mechanical ventilation after the second hospital day, have lower death rates during hospitalization and lower readmission rates for acute COPD exacerbations but more Clostridium difficile (PubMed). No good deed ever goes unpunished, huh?
Antibiotics for COPD is the perfect example of Newton's Second Law of the Medical Literature: for every study, there is an equal and opposite study. The Cochran review finds benefit for patients admitted to an ICU but for outpatients and inpatients, the results were inconsistent. (PubMed).
From the NEJM review (PubMed).
- Uncomplicated COPD (No risk factors: Age <65 years, FEV1 >50% predicted,<3 exacerbations per year, no cardiac disease) Advanced macrolide (azithromycin, clarithromycin) cephalosporin (cefuroxime, cefpodoxime, cefdinir) doxycycline, TMP/Sulfa. If recent antibiotic exposure (<3 months), use alternative class.
- Complicated COPD (1 or More risk factors: Age ≥65 years, FEV1 ≤50% predicted, ≥3 exacerbations per year, cardiac disease) Fluoroquinolone (moxifloxacin, levofloxacin) amoxicillin/clavulanate.
- even in patients severe enough to end up on a vent, ciprofloxacin is no better than trimethoprim/sulfamethoxazole (PubMed).
- If at risk for Pseudomonas infection, consider ciprofloxacin and obtain sputum culture.
If recent antibiotic exposure (<3months), use alternative class.
Doxycycline does not work for prolonging the interval to the next exacerbation (PubMed).
And don't forget the other stuff: bronchodilators, steroids, oxygen, etc.
Pearls
COPD exacerbations may be decreased by azithromycin, perhaps due to its immune-modulating effects ( PubMed).
Clarithromycin for acute exacerbations of chronic obstructive pulmonary disease or community-acquired pneumonia may be associated with increased cardiovascular events (PubMed).
Antibiotics do little for acute asthma except for increase cost and hospitalization (PubMed).
Colonization with Pseudomonas in outpatients is associated with higher morbidity and mortality (Pubmed).
Rants
It is probably vital so give the most expensive, the newest antibiotic you have recently been detailed on. Not.
Curious Cases
Relevant links to my Medscape blog
Last Update: 12/30/20.