Acute bronchitis: antibiotic no better than placebo

Acute bronchitis is coming into season again, and another study recently published in BMJ (British Medical Journal) offers further evidence that antibiotics are not helpful for uncomplicated acute bronchitis even when the sputum is discolored. The authors note:

"Acute bronchitis implies a self limiting infection of the large airways and is characterised by cough without pneumonia... Patients often return to their doctor or seek other medical help as symptoms may persist for two or three weeks, mainly cough, which may be bothersome for some patients and could last for up to four weeks or more... Acute bronchitis is mainly a viral infection...bronchial biopsy samples have never shown bacterial invasion. It is thought that acute bronchitis reflects an inflammatory response of the epithelium of the bronchi to infections."

Moreover...

"Most of these infections are self limiting, and several studies have suggested that the benefit of antimicrobial treatment is marginal. However, most patients with acute bronchitis receive antibiotics, even in countries with low rates of antibiotic prescribing. This over-prescription constitutes a global problem and is an important factor in increasing the levels of antibiotic resistance."

So they set out to...

"...evaluate the efficacy of oral anti-inflammatory or antibiotic treatment compared with placebo in the resolution of cough in patients with uncomplicated acute bronchitis and discoloured sputum."

So they randomized patients with cough, the presence of discolored sputum, and either difficulty breathing, wheezing, chest discomfort or chest pain to receive either the standard antibiotic moxicillin-clavulanic acid 500 mg/125 mg three times daily, ibuprofen 600 mg three times daily or placebo for 10 days. The antibiotic, and ibuprofen, both struck out:

"416 participants were randomised (136 to ibuprofen, 137 to antibiotic, and 143 to placebo) and 390 returned their symptom diaries fully completed. The median number of days with frequent cough was slightly lower among patients assigned to ibuprofen (9 days) compared with those receiving amoxicillin-clavulanic acid (11 days) or placebo (11 days), albeit without statistically significant differences. Neither amoxicillin-clavulanic acid nor ibuprofen increased the probability of cough resolution compared with placebo. Adverse events were observed in 27 patients, and were more common in the antibiotic arm (12%) than ibuprofen or placebo arms (5% and 3%)."

Clinical note: discolored sputum is not a reliable indication of bacterial infection. Comprehensive case management includes supporting resistance to opportunistic infections.The authors conclude:

"No significant differences were observed in the number of days with cough between patients with uncomplicated acute bronchitis and discoloured sputum treated with ibuprofen, amoxicillin-clavulanic acid, or placebo."