Bronchiectasis is an obstructive lung disease caused by the weakening or destruction of the muscle and elastic tissue in the bronchial tree (airway passages in the lungs). This condition may follow a chronic lung infection, or secondary to chronic bronchitis, a smoking-related problem, and lead to recurrent frequent pneumonia and if progressive, respiratory failure. Now two new studies are shedding light on the risks and benefits of using antibiotics to help treat patients.
Using the antibiotic azithromycin improved symptoms but also increased the risk of antibiotic resistance, according to a study in this week s JAMA.
One investigation was a randomized, placebo-controlled trial of 83 outpatients in the Netherlands with bronchiectasis, half of whom received placebo and the other half the macrolide antibiotic, azithromycin. The antibiotic reduced the risk of exacerbation by about one-third.
But 40 percent of the patients in the azithromycin group suffered gastrointestinal adverse effects, compared to just 5 percent in the placebo group. And 88 percent of those getting antibiotics developed macrolide resistance, compared to 26 percent in the placebo group.
On a related note, the FDA has approved an inhaled form of the powerful antibiotic, tobramycin, for patients with cystic fibrosis. This is related to the prior story because the genetic defect of CF leads to respiratory distress due to thick, viscoid mucus in the lungs, which fail to be cleared by normal respiratory mechanisms. The pooling of the mucus leads to a form of bronchiectasis, leading to recurrent pneumonia and inevitable respiratory failure. However, the lifespans of CF patients have been markedly increased by careful attention to respiratory therapy and antibiotics, both orally and inhalation. So the recent approval of Tobra is good news for the approximately 30,000 CF patients in the U.S.