The rate of macrolide resistance among Streptococcus pneumoniae is increasing, but some investigators have questioned its clinical relevance. We conducted a matched case-control study of patients with bacteremic pneumococcal infection at 4 hospitals to determine whether development of breakthrough bacteremia during macrolide treatment was related to macrolide susceptibility of the pneumococcal isolate. Case patients (n = 86) were patients who had pneumococcal bacteremia and an isolate that was either resistant or intermediately resistant to erythromycin. Controls (n = 141) were patients matched for age, sex, location, and year that bacteremia developed who had an erythromycin-susceptible pneumococcus isolated. Excluding patients with meningitis, 18 (24%) of 76 case patients and none of 136 matched controls were taking a macrolide when blood was obtained for culture (P = .00000012). Moreover, 5 (24%) of 21 case patients with the low-level-resistant M phenotype and none of 40 controls were taking a macrolide (P = .00157). These data show that development of breakthrough bacteremia during macrolide or azalide therapy is more likely to occur among patients infected with an erythromycin-resistant pneumococcus, and they also indicate that in vitro macrolide resistance resulting from both the efflux and methylase mechanisms is clinically relevant.
|Number of pages||9|
|Journal||Clinical Infectious Diseases|
|State||Published - 1 Sep 2002|
Bibliographical noteFunding Information:
Financial support: Centers for Disease Control and Prevention (Atlanta, Georgia; Epicenter grant UR8/CCU115089-01 [to A.A.M.]); La Fundacion para el Estudio de la Infección (Madrid, Spain; HMT-FEI 2000/3).
ASJC Scopus subject areas
- Microbiology (medical)
- Infectious Diseases