When guideline treatment of asthma fails, consider a macrolide antibiotic
This class of drugs has the potential to benefit patients with persistent, poorly controlled asthma and those with new-onset disease as an adjunct to first-line therapy.
PRACTICE RECOMMENDATIONS
› Consider a trial of azithromycin for patients who have poorly controlled persistent asthma and are not responding to guideline treatment with the combination of an inhaled corticosteroid and either a long-acting bronchodilator or long-acting muscarinic antagonist. B
› Consider a trial of azithromycin in addition to first-line guideline therapy for patients who have new-onset asthma. C
Strength of recommendation (SOR)
A Good-quality patient-oriented evidence
B Inconsistent or limited-quality patient-oriented evidence
C Consensus, usual practice, opinion, disease-oriented evidence, case series
Physicians should also note the landmark trial of azithromycin in severe, smoking-associated COPD, which found a clinically significant benefit in reducing exacerbations and improving quality of life (NNT = 3, to prevent 1 exacerbation).18
Case series. In a prospective case series (Level 2 study: prospective cohort), 163 primary care outpatients (adolescents and adults) who had acute wheezing illnesses or chronic asthma were evaluated for C pneumoniae infection by serologic testing.19 A subgroup of this cohort also had nasopharyngeal cultures tested for C pneumoniae.
Twenty patients (12%) were given a diagnosis of C pneumoniae infection defined by serology (n = 15), culture isolation (n = 3), or both (n = 2). Of the 20, 10 wheezed for the first time—6 of whom subsequently developed chronic asthma (n = 5) or chronic bronchitis (n = 1), with a serologic profile suggesting chronic infection. The other 10 patients who had a diagnosis of C pneumoniae infection already had a diagnosis of chronic asthma. In patients with established chronic asthma, initial serologic findings suggested chronic, rather than acute, C pneumoniae infection.
Tx recommendations: When to consider azithromycin
Randomized7 and nonrandomized15 evidence supports treating severely uncontrolled or refractory asthma (strength of recommendation [SOR], B); no comparable randomized trials of azithromycin have been conducted for new-onset asthma (SOR, C). Consider prescribing empiric azithromycin for patients with new-onset asthma in the context of shared decision making about potential benefits, harms, and consequences of chronic asthma (SOR, C).
It is important to note that wheezing is frequently associated with uncomplicated acute bronchitis that resolves spontaneously without antibiotic treatment.11 Azithromycin treatment for new-onset asthma should therefore be reserved for patients in whom apparent uncomplicated acute bronchitis fails to resolve after 3 to 6 months, and whose illness is diagnosable as asthma (see CASE 3).10
Continue to: Do biomarkers predict response?
