Level 2: Mid-level evidence
A randomized trial evaluated the effect of a modified antibiotic regimen in 302 adults hospitalized for severe community-acquired pneumonia (BMJ. 2006;333:1193; full-text available online free of charge at www.bmj.com/cgi/content/full/333/7580/1193. Accessed April 17, 2007).
Patients were randomized to early switch (to oral antibiotics after three days of IV antibiotics) vs. standard care (seven days of IV antibiotics).
Intention-to-treat analysis included 265 patients who were clinically stable at three days. Per-protocol analysis included 108 patients in the early-switch group (24 of 132 [18%] who did not switch to oral treatment) and 121 patients in the standard-care group (12 of 133 [9%] who had less than seven days of treatment).
Streptococcus pneumoniae was the microorganism identified in 19% of early-switch patients, compared with 31% of standard-care patients. The rates were similar for other identified causes and unknown for 56% vs. 47% of patients. Treatment failure was defined as death, remaining in the hospital at 28 days, an increase in temperature after initial improvement, the need for mechanical ventilation, a switch back to IV antibiotics, or readmission for pulmonary re-infection after discharge.
Comparing early switch vs. standard care in intention-to-treat analysis, the overall duration of antibiotics was 10.1 vs. 9.3 days (not significant) and the mean duration of IV antibiotics was 3.6 vs. 7 days (P <.05). The rates of treatment failure were 17% vs. 15% (95% confidence interval [CI] for difference -10% to +7%); 5% vs. 7% were still in the hospital at 28 days, 4% vs. 6% died, and 5% vs. 6% had other clinical deterioration. The mean time to meet discharge criteria was 5.2 vs. 5.7 days (not significant), and the mean length of hospital stay was 9.6 vs. 11.5 days (95% CI for difference 0.6-3.2 days).
Comparing early switch with standard care in per-protocol analysis, the mean duration of IV antibiotics was 3.3 vs. 7.5 days (P <.05). Treatment failure occurred in 14% vs. 17% (95% CI for difference -7% to +12%); 6% vs. 5% were still in the hospital at 28 days, 1% vs. 7% died, and 7% vs. 5% had other clinical deterioration. The mean length of hospital stay was 9 vs. 11.3 days (95% CI for difference 1-3.6 days).