Effect of macrolides as part of initial empiric therapy on medical outcomes for hospitalized patients with community-acquired pneumonia.

OBJECTIVE: The goal of this study was to compare the outcomes of hospitalized patients receiving a nonpseudomonal third-generation cephalosporin with or without a macrolide for the treatment of community-acquired pneumonia (CAP).

BACKGROUND: The initial treatment of CAP is usually based on empirically selected antibiotic therapy. The need for coverage of atypical pathogens in hospitalized patients is widely debated, and regional variations may exist.

METHODS: All patients admitted to a community hospital or to a university hospital for 1 year who were aged > or =18 years and had a principal discharge diagnosis of pneumonia with no organism specified according to the International Classification of Diseases, Ninth Revision, Clinical Modification were evaluated. Each patient's medical chart was reviewed by a clinical pharmacist at each facility. The following information was collected for each patient using a standardized form: demographic characteristics, coexisting illnesses, length of hospital and intensive care unit stays, antibiotic regimens, length of parenteral and oral therapy, laboratory and radiographic findings (ie, blood urea nitrogen, glucose, hematocrit, sodium, PO2, pH, and pleural effusion), physical examination results, and mortality. Patients treated with a nonpseudomonal third-generation cephalosporin with or without a macrolide were included in this analysis. Categoric variables were compared using the chi-square test or the Fisher exact test, and continuous variables were compared using the Mann-Whitney U test. A P value < 0.05 was considered statistically significant.

RESULTS: A total of 213 patients met the entry criteria and were treated with a nonpseudomonal third-generation cephalosporin with (116 patients) or without (97 patients) a macrolide. The mean (+/- SD) age of the patients was 62.2+/-19.6 years; 47% were male. The most common comorbid conditions were chronic obstructive pulmonary disease, diabetes mellitus, congestive heart failure, and cerebrovascular accident (CVA). Of the 116 patients who received a macrolide, the majority (66%) received erythromycin. Other macrolides used were clarithromycin (19%) and oral azithromycin (15%). There were no statistical differences between patients who did and did not receive a macrolide in terms of comorbid illnesses, length of hospital stay (5.2+/-2.8 vs 5.2+/-3.4 days, respectively), length of intravenous antibiotic therapy (4.4+/-2.5 vs 4.1+/-2.3 days, respectively), or mortality (0.9% vs 3.1%, respectively; P = 0.333). The only difference between the groups was in age. Those patients who received a macrolide were significantly younger than those who received only a nonpseudomonal third-generation cephalosporin (57.4+/-19.2 years vs 67.9+/-18.5 years; P < 0.001). However, when age and severity of illness were taken into account, no difference existed between the patients who received a nonpseudomonal third-generation cephalosporin alone or in combination with a macrolide.

CONCLUSIONS: We concluded that the addition of a macrolide to a nonpseudomonal third-generation cephalosporin as initial therapy for the treatment of CAP may not be necessary. A randomized, prospective clinical trial comparing a nonpseudomonal third-generation cephalosporin alone and in combination with a macrolide is warranted.