Background: Macrolides exert anti-inflammatory and immunomodulatory effects beyond their purely antibacterial action, as demonstrated by several bronchial inflammatory disorders, including asthma.
Fifty-eight children with newly diagnosed mild persistent asthma were selected by using the Global Initiative for Asthma guidelines and were randomly divided into the study (group I) (n = 36) and control (group II) (n = 22) groups. Mycoplasma pneumonia-specific immunoglobulin G and -specific immunoglobulin M antibody levels of each participant were measured by enzyme-linked immunosorbent assay. Clarithromycin 5 mg/kg daily and placebo were given to groups I and II, respectively, for 4 weeks. All of the children had maintenance inhaled corticosteroid (fluticasone propionate, one puff twice [50 μg/puff] daily). Forced expiratory volume in 1 second, forced expiratory flow at 25‐75% of the pulmonary volume, exhaled nitric oxide value, total IgE level, absolute eosinophil count, and eosinophilic cation protein value were measured at baseline and at the end of the treatment.
There are significantly increased forced expiratory volume in 1 second and forced expiratory flow at 25‐75% of the pulmonary volume levels and decreased exhaled nitric oxide values after the 4-week clarithromycin treatment. The study group also had a decreased peripheral blood absolute eosinophil count and eosinophilic cation protein level, but not for the total IgE level, after the treatment.
Four weeks of sub-antimicrobial doses of clarithromycin may improve pulmonary function and decrease eosinophilic inflammation in children with asthma.